(19)
(11)EP 3 405 459 B1

(12)EUROPEAN PATENT SPECIFICATION

(45)Mention of the grant of the patent:
10.06.2020 Bulletin 2020/24

(21)Application number: 17700696.2

(22)Date of filing:  20.01.2017
(51)International Patent Classification (IPC): 
C07D 251/70(2006.01)
C09B 67/46(2006.01)
C09B 67/20(2006.01)
(86)International application number:
PCT/EP2017/051134
(87)International publication number:
WO 2017/125524 (27.07.2017 Gazette  2017/30)

(54)

MELAMINE-POLYETHERS AS DISPERSANTS IN NON-AQUEOUS, LIQUID PIGMENT COMPOSITIONS

MELAMINE-POLYETHER ALS DISPERSIONSMITTEL IN NICHT-WÄSSRIGEN, FLÜSSIGEN PIGMENT-ZUSAMMENSETZUNGEN

POLYÉTHERS DE MÉLAMINE EN TANT QUE DISPERSANTS EN COMPOSITIONS DE PIGMENTS LIQUIDES, NON AQUEUX


(84)Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30)Priority: 22.01.2016 EP 16152449

(43)Date of publication of application:
28.11.2018 Bulletin 2018/48

(73)Proprietor: BASF SE
67056 Ludwigshafen am Rhein (DE)

(72)Inventors:
  • BOERZSOENYI, Gabor
    67056 Ludwigshafen am Rhein (DE)
  • DURIS, Tibor
    67056 Ludwigshafen am Rhein (DE)
  • WEINKOETZ, Stephan
    67056 Ludwisghafen am Rhein (DE)
  • REUTER, Frank
    67056 Ludwigshafen am Rhein (DE)
  • PIRRUNG, Frank
    67056 Ludwisghafen am Rhein (DE)


(56)References cited: : 
DE-A1- 2 365 752
JP-A- 2009 235 167
  
  • DATABASE CA [Online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; 1968, WIRPSZA, ZYGMUNT ET AL: "Melamine presspowder modified with bis-urethanes and bis-ethers of glycols with monohydroxymethylmelamine", XP002755181, retrieved from STN Database accession no. 1980:59508 & WIRPSZA, ZYGMUNT ET AL: "Melamine presspowder modified with bis-urethanes and bis-ethers of glycols with monohydroxymethylmelamine", PREPR. SHORT CONTRIB. - BRATISLAVA IUPAC INT. CONF. MODIF. POLYM.; PUBLISHER: SLOV. AKAD. VIED, USTAV POLYM., CODEN: 42AQAE, vol. 1, no. 49, 1979, BRATISLAVA, CZECH.
  • DATABASE CA [Online] CHEMICAL ABSTRACTS SERVICE, COLUMBUS, OHIO, US; 1964, LEVI, S. M. ET AL: "Tanning properties of compounds containing methylol groups", XP002755182, retrieved from STN Database accession no. 1964:408923 & LEVI, S. M. ET AL: "Tanning properties of compounds containing methylol groups", TR. VSES. NAUCHN.-ISSLED. KINOFOTOINST., vol. 51, 1962, pages 80-94,
  
Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


Description


[0001] The present invention relates to novel mixtures of mono- or polynuclear melamine compounds and their use as dispersants for pigments and fillers in coating compositions, in particular in solvent-borne coating compositions.

BACKGROUND OF THE INVENTION



[0002] Pigments are ordinarily organic or inorganic dry powders that incorporate a mixture of primary particles, aggregates and agglomerates. For both industrial and consumer coating compositions, whether solvent borne or water borne, the pigment should be dispersed homogeneously throughout the coating composition in order to ensure a uniform appearance of the final coating. To be properly dispersed, pigments are usually wetted, deaggregated and deagglomerated in a vehicle to obtain a dispersion of the pigment particles. Wetting involves incorporation of the pigment into the vehicle replacing pigment-air interfaces with pigment-vehicle interfaces. Wetting agents facilitate bringing pigments into a dispersed state as a result of surface activity at the pigment-solution interface. An ideal pigment dispersion consists of a homogenous suspension of particles, after reducing the size of any aggregates and agglomerates.

[0003] While some organic vehicles may be good pigment wetting agents themselves, dispersants are typically added to the liquid vehicle to ensure thorough pigment dispersion throughout the vehicle. Dispersants can also be used to temporarily stabilize the pigment dispersion from re-aggregating and re-agglomerating. Problems that occur with current available pigment compositions include (i) a separation or settling of the compositions into their components over time which can require periodic remixing or stirring, and (ii) an undesirable change in rheological profile.

[0004] Liquid pigment compositions containing pigments and fillers and a liquid vehicle are used in an almost unlimited number of different technical applications, in particular for colouring coating compositions, including solvent and water-borne paints, heavy duty coatings, automotive coatings, in printing inks, or for colouring cosmetics, plastics etc.

[0005] The function of dispersants is manifold. Mainly, they act as stabilizers for the solid fine particulate materials in the liquid pigment compositions, i.e. the dispersant separates the particles of the solid fine particulate material and thus prevents them from coagulation or clumping and settling from the liquid vehicle. They also may act as solubilizers in the given carrier liquid of a coating composition. Dispersants may also improve the optical properties of the coatings, such as gloss, colour intensity or rub-out characteristics. Depending on the type and polarity of the vehicle, e.g. water, organic solvents or mixtures thereof, polymers of variable structure are used as dispersants.

[0006] A general survey on the different types of polymeric dispersants, their polymeric architecture and their properties is given by F. Pirrung and C. Auschra in Macromolecular Engineering, Precise Synthesis, Materials Properties, Applications (ed. K. Matyjaszewski et al.), chapter 4, polymeric dispersants, pp. 2135-2180.

[0007] Although a large number of dispersants for pigment compositions have been described in the art, there is still a need for dispersants, which provide for a good rheological behavior of the pigment composition and which allow for formulation of pigment compositions, which can be easily incorporated in solvent borne coating compositions, which provide a high color strength and also for good rub out characteristics. For economical reasons, dispersants are required, which can be produced in a simple manner using readily available starting materials. Moreover, the dispersants should be compatible with other ingredients of the pigment compositions and the coating compositions.

[0008] L. Yanshan et al., Solar Energy Materials & Solar Cells, 127 (2014), 92 - 97 describe solid-solid phase change materials based on highly crosslinked melamine polymers, which are obtained by the reaction of melamine, formaldehyde and polyethylene glycol.

[0009] S.M. Levi et al., "Tanning properties of compounds containing methylol groups", Tr. Vses. Nauchn.-Issled. Kinofotoinst. Vol. 51, 1962, pages 80 - 94, describe the mononuclear melamine compound N2,N2,N4,N4,N6,N6-hexakis[[2-(2-methoxyethoxy)ethoxy]methyl]-2,4,6-triamino-1,3,5-triazine.

[0010] Zygmunt Wirpsza et al., "Melamine presspowder modified with bis-urethanes and bis-ethers of glycols with monohydroxymethylmelamine", Prepr. Short. Contrib. - Bratislava IUPAC Int. Conf. Modif. Polym. 5th (1979), Vol. 1, 49 (publisher: Slov. Adad. Vied, Ustav Polym., Bratislava, Czech), describe the condensation of binuclear melamine compounds of the formula A with formaldehyde. The compounds are suggested for use in melamine presspowder.

R = (CH2)4 or (CH2CH2O)nCH2CH2, where n is 1, 6, 8 or 21.

[0011] JP 2009 235167 A describes pigment compositions or pigment dispersions which contain a melamine compound having a sulfonamide linked polyether chain, i.e. a group CH2-SO2-NH-X, where X represents a polyether group.

[0012] DE 23 65 752 A1 describes alkoxylated N-methylolaminotriazine compounds which are particularly useful as reactive surfactants.

SUMMARY OF THE INVENTION



[0013] It was surprisingly found that the above problems are solved by mixtures of the mono- or polynuclear melamine compounds described hereinafter. These mixtures of mono- or polynuclear melamine compounds are suitable as dispersants for fine particulate materials, such as pigments and fillers in organic vehicles and therefore allow the preparation of liquid pigment compositions, which can be easily incorporated into solvent borne coating compositions.

[0014] Therefore, a first aspect of the present invention relates to mixtures of the mono- or polynuclear melamine compounds, as described hereinafter.

[0015] The mono- or polynuclear melamine compounds of the mixtures according to the invention have at least one 2,4,6-triamino-1,3,5-triazine ring, wherein at least one amino groups of at least one of the 2,4,6-triamino-1,3,5-triazine rings of the mono- or polynuclear melamine compounds is of the formula A:

        NR1R2     (A)

where
R1
is H, CH(R3)OR4 or R2,
R2
is CH(R3)O(A-O)x-R5, where
R3 is H, C1-C10-alkyl or aryl;
R4 is H, C1-C4-alkyl or C1-C4-alkoxy-C1-C4-alkyl;
R5
is a hydrocarbon radical having from 1 to 40 carbon atoms, which is selected from C1-C22-alkyl, aryl-C1-C4-alkyl or aryl, where aryl in the last two mentioned radicals is phenyl or naphthyl, which is unsubstituted or carries 1 or 2 C1-C10-alkyl group;
x
is an integer from 2 to 500, having a number average value in the range from 3 to 200;
A
is an C2-C4-alkan-1,2-diyl radical;
where the mono- or polynuclear melamine compounds are selected from mononuclear melamine compounds of the formula (M1), binuclear polynuclear melamine compounds of the formula (M2) and polynuclear melamine compounds of the formulae (M3),





where in formula M1
at least one of the radicals A1, A2 and A3 is a radical of the formula (A), while the remaining radicals are of the formulae NHRx or NRxRy, respectively;
where in formula M2
at least one of the radicals A1, A2, A4 and A5 is a radical of the formula (A), while the remaining radicals A1, A2, A4 and/or A5 are of the formulae NHRx or NRxRy, respectively,
L is a bivalent linker CH(R3) or CH(R3)[O-CH(R3)]k, where k is an integer, which is in the range from 1 to 5, and
A33 and A34 are radicals NRz,
and where in formula M3
at least one of the radicals A6, A7 and A8 is a radical of the formula Ma

wherein p is 0 or an integer from 1 to 20, provided that in at least one of the groups Ma the variable p is different from 0,

# indicates the point of attachment to the triazine ring of M3,

L and L' are identical or different bivalent linkers as defined for L in formula M2, A33, A34, A35 and A36 are radicals NRz,

provided at least one of the radicals A2, A4, A5, A6, A7 and A8 is a radical of the formula (A), while the remaining radicals A2, A4 and A5, are of the formulae NHRx or NRxRy, respectively, and the remaining radicals A6 and A7, are of the formulae Ma, NHRx or NRxRy, respectively,

and where
Rx
is CH(R3)OR4 or CH(R3)O-R8,
Ry
is CH(R3)OR4 or CH(R3)O-R8,
Rz
is hydrogen, CH(R3)OR4 or CH(R3)O-R8, and
R8
is a hydrocarbon radical having from 5 to 40 carbon atoms.


[0016] The new mixtures of mono- or polynuclear melamine compounds of the invention can be prepared by the following two processes 1 and 2, as described herein. These processes are also part of the invention.

[0017] Process 1 is a two step process and comprises the following steps:
  1. a) reacting 2,4,6-triamino-1,3,5-triazine and an aldehyde of the formula R3-CHO and optionally an alcohol R4a-OH,
  2. b) reacting the reaction product of step a) with a polyether of formula (II)

            R5-[O-A]xOH     (II)

    and optionally with an alcohol R8-OH,
wherein R3, R5, R8, A and x are as defined herein and R4a has one of the meanings given for R4 but is different from hydrogen.

[0018] Process 2 is a single-step process and comprises reacting a polyether of formula (II), as defined above, with 2,4,6-triamino-1,3,5-triazine and an aldehyde of the formula R3-CHO, wherein R3 is as defined herein, and optionally an alcohol R4a-OH or R8-OH, wherein R4a and R8 are as defined herein.

[0019] Both process 1 and process 2 are polycondensation reactions, which result in a mixture of mono- and polynuclear melamine compounds, which can either be separated or used as mixtures.

[0020] The mixtures of mono- or polynuclear melamine compounds of the invention, which are obtained by the processes of the invention, are suitable as dispersants for pigment materials and work in particular in hydrophobic carriers. They provide for a good rheological behavior of the pigment composition and allow for formulation of pigment compositions, which can be easily incorporated in solvent borne coating compositions, which provide a high color strength and also for good rub out characteristics.

[0021] Therefore, the present invention also relates to the use of the mixtures of melamine compounds as described herein as dispersants in non-aqueous, i.e. solvent based, liquid pigment compositions, in particular in pigment pastes and colorants.

[0022] The present invention also relates to non-aqueous, i.e. solvent-based, liquid pigment composition, comprising a mixture of melamine compounds as described herein, a pigment component and a non-aqueous diluent.

DETAILED DESCRIPTION OF THE INVENTION



[0023] Here and in the following, the term "pigment component" relates to pigments and mixtures of at least one pigment and at least one particulate non-pigment material, hence, filler.

[0024] The term "mono- or polynuclear melamine compound" is understood to mean a mono-, bi- or polynuclear melamine compound of the formulae (M1), (M2) or (M3) as defined herein, which has at least one radical derived from 2,4,6-triamino-s-triazine, wherein at least one of the amino groups of at least one of the melamine radicals contained in the mono- or polynuclear melamine compounds is a radical of the formula (A) as described herein. A mononuclear melamine compound has a single radical derived from 2,4,6-triamino-s-triazine, while a polynuclear melamine compound has at least 2, e.g. from 2 to 20, radicals derived from 2,4,6-triamino-s-triazine, depending on the molecular weight of the polynuclear melamine compound. A polynuclear melamine compound which has 2 radicals derived from 2,4,6-triamino-s-triazine is also termed as binuclear melamine compound, while a polynuclear melamine compound which has 3 radicals derived from 2,4,6-triamino-s-triazine will also be termed as trinuclear melamine compound, and so on.

[0025] It is apparent to a skilled person that a mononuclear melamine compound of a mixture according to the invention has 3 amino groups, where at least one of these aminogroups is of the formula (A) as described herein. It is also apparent to a skilled person that a binuclear melamine compound of a mixture according to the invention has 6 amino groups, where at least one of these aminogroups is of the formula (A) as described herein and where 2 amino groups are linked by a bivalent linker as described herein. It is also apparent to a skilled person that a polynuclear melamine compound of a mixture according to the invention, which has m radicals derived from 2,4,6-triamino-s-triazine, will have 3m amino groups, where at least one of these aminogroups is of the formula (A) as described herein and where 2(m-1) amino groups are linked in pairs by a bivalent linker as described herein.

[0026] It is apparent to a skilled person that in the mono- or polynuclear melamine compounds of the mixtures according to the invention, those aminogroups, which are not of the formula (A) and which are not linked by a linker may be primary aminogroups, i.e. NH2, secondary amino groups NHRx and tertiary amino groups NRxRy, where Rx and Ry are organic radicals different from hydrogen and e.g. radicals CH(R3)OR4 or CH(R3)O-R8, where R3, R4 and R8 are as defined herein.

[0027] A mono-nuclear melamine compound of a mixture according to the invention has the following formula M1

where at least one of the radicals A1, A2 and A3 is a radical of the formula (A), while the remaining radicals are of the formulae NHRx or NRxRy, respectively.

[0028] A binuclear melamine compound of a mixture according to the invention is described by the following formula M2

where at least one of the radicals A1, A2, A4 and A5 is a radical of the formula (A), while the remaining radicals A1, A2, A4 and/or A5 are of the formulae NHRx or NRxRy, respectively. L is a bivalent linker selected from linear or branched alkandiyl, which is optionally interrupted by oxygen atoms and which is CH(R3) or CH(R3)[O-CH(R3)]k, where k is an integer, which is in the range from 1 to 5, and where R3 is as defined herein. A33 and A34 are tradicals NRz, where Rz is hydrogen or a radical CH(R3)OR4 or CH(R3)O-R8, where R3, R4 and R8 are as defined herein.

[0029] It is apparent that a polynuclear melamine compound of a mixture according to the invention, which is different from a binuclear melamine compound, is described by the following formula M3,

where at least one of the radicals A6, A7 and A8 is a radical of the formula Ma

wherein p is 0 or an integer, e.g. from 1 to 20, provided that in at least one of the groups Ma the variable p is different from 0,

# indicates the point of attachment to the triazine ring of M3,

L and L' are identical or different bivalent linkers as defined for L in formula M2,

A33, A34, A35 and A36 are typically radicals NRz, where Rz is as defined for formula M2,

provided at least one of the radicals A2, A4, A5, A6, A7 and A8 is a radical of the formula (A), while the remaining radicals A2, A4 and A5, are of the formulae NHRx or NRxRy, respectively, and the remaining radicals A6 and A7, are of the formulae Ma, NHRx or NRxRy, respectively.



[0030] Hydrocarbon radicals having 1 to 40 carbon atoms include but are not limited to:
  1. i. alkyl having 1 to 40 carbon atoms,
  2. ii. alkenyl having 2 to 40 carbon atoms,
  3. iii. cycloalkyl having 3 to 10 carbon atoms, which may be substituted by 1 to 6 alkyl groups, each of which may have 1 to 6 carbon atoms,
  4. iv. aryl having 6 to 10 carbon atoms, which may be substituted by 1 to 6 alkyl groups, each of which may have 1 to 6 carbon atoms,
  5. v. alkyl having 1 to 6 carbon atoms, which is substituted by cycloalkyl having 6 to 10 carbon atoms, which cycloalkyl may be substituted by 1 to 6 alkyl groups, each of which may have 1 to 6 carbon atoms,
  6. vi. alkyl having 1 to 6 carbon atoms, which is substituted by aryl having 6 to 10 carbon atoms, which may be substituted by 1 to 6 alkyl groups, each of which may have 1 to 6 carbon atoms.


[0031] Here and in the following the prefix Cn-Cm indicates the number of carbon atoms a radical or compound may have. For example, the prefix C1-C4 indicates that the radical, moiety or compound may have from 1 to 4 carbon atoms.

[0032] Alkyl denominates a saturated linear or branched, acyclic hydrocarbon radical, which may have from 1 to 40 carbon atoms (C1-C40-alkyl). The term C1-C4-alkyl indicates alkyl having from 1 to 4 carbon atoms, such as methyl, ethyl, n-propyl, 2-propyl, n-butyl, 2-butyl, isobutyl, 1,1-dimethylethyl. The term C1-C6-alkyl indicates alkyl having from 1 to 6 carbon atoms, such as methyl, ethyl, n-propyl, 2-propyl, n-butyl, 2-butyl, isobutyl, 1,1-dimethylethyl, n-pentyl, 2-pentyl, neopentyl, n-hexyl, 2-hexyl, 2-methylpentyl, 1,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl, etc.. The term C1-C10-alkyl indicates alkyl having from 1 to 10 carbon atoms, such as C1-C6-alkyl mentioned before and also , n-heptyl, 1-methylhexyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 1-ethylpentyl, 2-ethylpentyl, 3-ethylpentyl, n-octyl, 1-methylheptyl, 2-methylheptyl, 1-ethylhexyl, 2-ethylhexyl, 1,2-dimethylhexyl, 1-propylpentyl, 2-propylpentyl, n-nonyl, decyl, 2-propylheptyl, and 3-propylheptyl. The term C6-C20-alkyl indicates alkyl having from 6 to 20 carbon atoms, such as n-hexyl and its isomers, n-heptyl, 1-methylhexyl, 2-methylhexyl, 3-methylhexyl, 4-methylhexyl, 5-methylhexyl, 1-ethylpentyl, 2-ethylpentyl, 3-ethylpentyl, n-octyl, 1-methylheptyl, 2-methylheptyl, 1-ethylhexyl, 2-ethylhexyl, 1,2-dimethylhexyl, 1-propylpentyl, 2-propylpentyl, n-nonyl, decyl, 2-propylheptyl, 3-propylheptyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-hexadecyl, n-octadecyl, n-eicosyl, n-docosenyl (behenyl), lignoceryl and constitutional isomers of the aforementioned n-alkyl radicals.

[0033] Alkenyl denominates an ethylenically unsaturated linear or branched hydrocarbon radical, which may have from 2 to 40 carbon atoms (C2-C30-alkenyl) and which may have 1, 2, 3 or 4 C=C double bonds.

[0034] Cycloalkyl denominates a saturated mono- or bicyclic hydrocarbon radical having usually 3 to 10 carbon atoms, monocyclic radicals such as cyclopropyl, cyclobutyl, cyclopentyl, cycloheptyl, cyclooctyl, etc. Examples of bicyclic radicals comprise bicyclo[2.1.1]hexyl, bicyclo[2.2.1]heptyl, bicyclo[3.1.1]heptyl, bicyclo[2.2.1]heptyl, bicyclo[2.2.2]octyl and bicyclo[3.2.1]octyl.

[0035] Aryl denominates an aromatic hydrocarbon atom such as phenyl or naphthyl, which may have a fused carbocyclic ring, such as in indanyl, indenyl, fluoranyl etc. Aryl denominates in particular phenyl and naphthyl.

[0036] Alkylen and Alkandiyl denominate linear or branched, saturated bivalent hydrocarbon radicals having usually 1 to 8 carbon atoms, such as methylene, 1,2-ethandiyl, 1,1-ethandiyl, 1,1-propandiyl, 1,2-propandiyl, 2,2-propandiyl, 1,3-propandiyl, 2-methyl-2,3-propandiyl, 1,1-butandiyl, 1,2-butandiyl, 2,2-butandiyl, 2,3-butandiyl, 1,3-butandiyl and 1,4-butandiyl. Likewise, alkantriyl and alkantetrayl, denominate linear or branched, saturated tri- and tetravalent hydrocarbon radicals having usually 1 to 8 carbon atoms, such as ethan-1,1,2-triyl, propan-1,2,3-triyl.

[0037] The term C2-C4-alkan-1,2-diyl denominates a bivalent hydrocarbon radical having from 2 to 4 carbon atoms. Examples of C2-C4-alkan-1,2-diyl include ethan-1,2-diyl, propan-1,2-diyl, butan-1,2-diyl, and 2-methylpropan-1,2-diyl.

[0038] Alkendiyl denominates linear or branched, unsaturated bivalent hydrocarbon radicals having usually 2 to 8 carbon atoms, such as ethen-1,1-diyl (C=CH2), ethen-1,2-diyl, (-CH=CH-), propen-1,2-diyl (-CH=C(CH3)-), propen-2,3-diyl (-CH2-C(=CH2)-) or propen-1,3-diyl (-CH2-CH=CH-). Likewise, alkantriyl and alkantetrayl, denominate linear or branched, saturated tri- and tetravalent hydrocarbon radicals having usually 2 to 8 carbon atoms, such as propen-1,2,3-triyl (-CH=C(-)-CH2-).

[0039] Cycloalkandiyl denominates cyclic saturated bivalent hydrocarbon radicals having usually 3 to 8 carbon atoms, such as cyclopropane-1,1-diyl, cyclopropane-1,2-diyl, cyclobutan-1,1-diyl, cyclobutan-1,2-diyl, cyclobutan-1,3-diyl, cyclopentan-1,1-diyl, cyclopentan-1,2-diyl, cyclopentan-1,3-diyl, cyclohexan-1,1-diyl, cyclohexan-1,2-diyl, cyclohexan-1,3-diyl or cyclohexan-1,4-diyl.

[0040] A skilled person will readily understand that the variable x relates to the number of repeating units O-A in the polyether group O(A-O)x-R5 and that number of repeating units in the molecules contained in a sample is not identical for each molecule contained in the sample but represents an average. Therefore, the number average is frequently in the range from 3 to 200, in particular from 3 to 100, more particularly 4 to 80 and especially 5 to 60 or 5 to 30.

[0041] It is also apparent for a skilled person that the radical O(A-O)x-R5 in formula (A) stems from the polyether of formula (II), while the radical R3 stems from the aldehyde R3-CHO. It is also apparent that any radical OR4 and OR8 stems from alcohols used in processes 1 and 2.

[0042] The variables A, x and R5 in the group CH(R3)O(A-O)x-R5, and likewise in the polyether of the formula (II) may individually on their own and preferably in combination have the following meanings:
A
is selected from the group consisting of ethan-1,2-diyl and propan-1,2-diyl and combinations thereof;
x
is an integer having a number average value in the range from 3 to 100, more particularly 4 to 80 and especially 5 to 60 or 5 to 30;
R5
is C1-C22-alkyl, aryl-C1-C4-alkyl or aryl, where aryl in the last two mentioned radicals is phenyl or naphthyl, which is unsubstituted or carries 1 or 2 C1-C4-alkyl groups and especially methyl groups.


[0043] More particularly, the variables A, x and R5 in the group CH(R3)O(A-O)x-R5, and likewise in the polyether of the formula (II) may individually on their own and preferably in combination have the following meanings:
A
is ethan-1,2-diyl;
x
is an integer having a number average value in the range from 5 to 60, especially in the range from 5 to 30;
R5
is C1-C4-alkyl, especially methyl.


[0044] Apart from that, the radical R1 in formula (A) is preferably hydrogen.

[0045] In addition to the group of formula (A), one or more of the melamine rings in the mono- or polynuclear melamine compounds may bear a group of formula (B):

        NR6R7     (B)

where
R6
is H or CH(R3)OR4,
R7
is CH(R3)O-R8, where
R3 is H, C1-C10-alkyl or aryl;
R4 is H, C1-C4-alkyl or C1-C4-alkoxy-C1-C4-alkyl;
R8 is a hydrocarbon radical having from 1 to 40 carbon atoms.


[0046] In the context of formulae (A) and (B), the radical R3 in the radicals CH(R3)OR4, CH(R3)OR8 and CH(R3)O(A-O)x-R5, respectively, is preferably different from hydrogen and in particular selected from C1-C4-alkyl and phenyl, more particularly C1-C4-alkyl and especially ethyl.

[0047] In the context of formulae (A) and (B), the radical R4 in the radical CH(R3)OR4 is preferably different from hydrogen and is in particular C1-C4-alkyl.

[0048] In the context of formula (B), the radical R6 is preferably hydrogen.

[0049] In the context of formula (B), the radical R8 is preferably C8-C20-alkyl or C8-C20-alkenyl.

[0050] According to the invention at least one of the amino groups of at least one of the melamine radicals contained in the mono- or polynuclear melamine compound is a radical of the formula (A) as described herein.

[0051] In particular, at least 10 mol-%, in particular at least 15 mol-% and especially at least 20 mol-% or at least 25 mol-% of the total number of amino groups bound to an s-triazine ring in the compounds of the invention are an amino group of formula (A). An amino group of formula (A) result from the reaction of an amino group of the s-triazine with the aldehyde R3-CHO and the polyether of formula (II) and optionally an alcohol R4a-OH. The amount of amino groups of formula (A) may be as high as 100 mol-% in mono-nuclear melamine compounds and up to 95 mol-% in polynuclear melamine compounds, in each case based on the total number of amino groups bound to the s-triazine rings of the mono- or polynuclear melamine compounds. Frequently, it does not exceed 90 mol-% of the total number of amino groups bound to an s-triazine ring in the compounds of the invention.

[0052] Frequently, at least 30 mol-%, in particular at least 45 mol-%, especially at least 60 mol-% or at least 75 mol-% of the melamine rings, i.e. the s-triazine rings, bear at least one amino group of formula (A).

[0053] The amount of amino groups of the formula (B), will generally not exceed 50 mol-% or 30 mol-%, of the total number of amino groups bound to an s-triazine ring in the compounds of the invention. If present, the amount of amino groups of the formula (B) will generally be in the range from 1 to 50 mol-% in particular from 5 to 30 mol-% of the total number of amino groups bound to an s-triazine ring in the compounds of the invention. In another embodiment of the invention, the mono- or polynuclear melamine compounds of the present invention do not contain no or virtually no amino groups of formula (B).

[0054] Besides the amino groups of formulae (A) and (B), the mono- or polynuclear melamine compounds may contain one or more amino groups of formula (C)

        NR9R10     (C)

where
R9
is H or CH(R3)OR4,
R10
is CH(R3)O-R4, where
R3 is H, C1-C10-alkyl or aryl, and
R4 is H, C1-C4-alkyl or C1-C4-alkoxy-C1-C4-alkyl,
and/or amino groups (D), which are linked to an amino group of another triazine ring via a bivalent linker, such as CH(R3) or a CH(R3)[O-CH(R3)]k, where k is an integer, which is frequently in the range from 1 to 5, and where R3 is as defined herein. Together with amino groups of formulae (A) and (B), the amino groups (C) and (D) will frequently amount to at least 90 mol-%, in particular at least 95 mol-% or at least 99 mol-% of the total number of amino groups bound to an s-triazine ring in the compounds of the invention. Amino groups (D), which are linked to an amino group of another triazine ring via a bivalent linker, can be described by the formula NRz, where Rz is hydrogen or an organic radical different from hydrogen, such as a radical CH(R3)OR4 or CH(R3)O-R8, where R3, R4 and R8 are as defined herein.

[0055] A skilled person will readily understand that the mol-%ages given here are average numbers based on the molecules present in a sample of the mono or polynuclear melamine compound.

[0056] With regard to the capability of the mono- or polynuclear melamine compounds of the present invention to act as dispersants, the amount of the radicals O(A-O)x-R5 is frequently at least 10% by weight and up to 99% by weight, based on the total weight of the melamine compound. Frequently, the amount of the radicals O(A-O)x-R5 is in the range from 20 to 95% by weight, in particular from 30 to 90% by weight, based on the total weight of the melamine compound.

[0057] Due to the presence of the radicals O(A-O)x-R5 and also due to the potential presence of more than one s-triazine ring, the melamine compounds have to be considered as oligomers or polymers, respectively. The number average weight of these compounds is frequently in the range from 320 to 200000, in particular from 520 to 120000, especially from 600 to 12000. The number average molecular weight can be determined by gelpermeation chromatography (GPC).

[0058] As outlined above, the mixtures of mono- or polynuclear melamine compounds of the invention can be prepared by both process 1 and process 2. Both processes will result in comparable products, which frequently will contain a mixture of mono- and polynuclear melamine compounds as described herein. However, processes 1 and 2 can be conducted in a manner to specifically yield a mononuclear melamine compound.

[0059] In step a) of process 1 of the invention it is preferred to react 2,4,6-triamino-1,3,5-triazine, an aldehyde of the formula R3-CHO and an alcohol R4a-OH, which is preferably a primary C1-C4-alkanol, such as methanol, ethanol, n-propanol, n-butanol or iso-butanol or a secondary alcohol such as isopropanol or 2-butanol. Preferred aldehydes are those, wherein R3 is different from hydrogen. Preferred aldehydes include C2-C4-alkanals such as acetaldehyde, propionaldehyde or butyraldehyde, and benzaldehyde or substituted benzaldehyde, with particular preference given to C2-C4-alkanals, especially to propanal.

[0060] The reaction of the aldehyde of the formula R3-CHO with the amino groups in 2,4,6-triamino-1,3,5-triazine results in a semi-aminal group, i.e. a group of formulae NH-CH(R3)OH or N-(CH(R3)OH)2 or Schiff's base N=C(R3). Both, the semiaminal and Schiff's base may undergo a reaction with the alcohol R4a-OH, thus forming a moiety NH-CH(R3)-OR4a or N(CH(R3)-OR4a)2 either by etherification of the hydroxyl group of the semi-aminal or by addition of the alcohol R4a-OH to the C=N-bond.

[0061] The relative amount of aldehyde R3-CHO used in step a) is frequently in the range from 0.25 to 3.0 mol, in particular from 0.3 to 2.5 mol, especially from 0.35 to 2.3 mol per mol of NH2-groups in the 2,4,6-triamino-1,3,5-triazine or from 0.75 to 9 mol, in particular from 0.9 to 7.5 mol, especially from 1.05 to 6.9 mol per mol of 2,4,6-triamino-1,3,5-triazine. If present, the amount of alcohol R4a-OH is usually at least 0.2, in particular at least 0.5 mol, especially at least 1 mol per mol of aldehyde R3-CHO. The alcohol R4a-OH may also be used as a solvent and thus, its amount may be e.g. as high as to 100 mol or up to 50 mol per mol of the aldehyde.

[0062] Step a) of process 1 can be performed by analogy to the methods for producing melamine formaldehyde precondensates as described in Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd edition, Vol. 2, pp. 440-469, US 4,918,317, EP 26914, EP 218887, EP 319337, EP 383,337, EP 415273, DE 19833347, DE 19835114 and WO 01/51197.

[0063] Frequently, the reaction is performed by mixing the aldehyde R3-CHO and melamine in the desired amount, optionally in a solvent, such as water or an alcohol R4a-OH. The reaction is normally achieved simply by mixing the reactants of step a) and optionally warming the mixture of the aldehyde R3-CHO and melamine and optionally the solvent, such as water or an alcohol R4a-OH, to the reaction temperature. The reaction temperature is frequently in the range from 30 to 80°C, in particular form 35 to 70°C. The reaction of step a) is usually performed at ambient pressure, but it can also be performed at reduced pressure or slightly increased pressure. Normally, the reaction of step a) will be performed at a pressure in the range from 900 to 1200 hPa. Preferably step a) is performed in the absence of an acidic or basic catalyst.

[0064] In step b) the intermediate of step a) is reacted with the polyether of formula (II).

[0065] The amount of polyether of formula (II) used in the reaction of step b) will frequently be at least 10 mol-%, in particular at least 15 mol-% and especially at least 20 mol-% or at least 25 mol-% based on the total number of amino groups present in the reaction product of step a). The amount of polyether of formula (II) may be as high as 200 mol-% in particular up to 180 mol-%, based on the total number of amino groups present in the reaction product of step a). Frequently, it is in the range from 30 to 120 mol-%, based on the total number of amino groups present in the reaction product of step a).

[0066] Frequently, the amount of polyether of formula (II) used in the reaction of step b) will be at least 30 mol-%, in particular at least 45 mol-%, especially at least 60 mol-% or at least 75 mol-% of the melamine rings present in the reaction product of step a).

[0067] Frequently, the amount of polyether of formula (II) used in the reaction of step b) will be in the range from 10 to 99% by weight, based on the total weight of the intermediate formed in step a). Preferably, the amount of polyether of formula (II) used in the reaction of step b) will be in the range from 20 to 95% by weight, in particular from 30 to 90% by weight, based on the total weight of the intermediate formed in step a).

[0068] A part of the polyether of formula (II) may be replaced by an alcohol of the formula R8-OH, where R8 is as defined above. However, the amount of the alcohol of the formula R8-OH will generally not exceed 50 mol-%, in particular 30 mol-%, based on the total amount of alcohol R8-OH and polyether of formula (II). If present, the amount of the alcohol of the formula R8-OH will frequently in the range from 1 to 50 mol-% in particular from 5 to 30 mol-%, based on the total amount of alcohol R8-OH and polyether of formula (II). Preferably, no alcohol of formula R8-OH is present in the reaction of step b) of process 1.

[0069] The reaction of step b) is frequently performed in the presence of an acidic or a basic catalyst, preferably an acidic catalyst and in particular a Broenstedt acid catalyst. However, Lewis acid catalysts can also be used. The amount of catalyst is frequently in the range from 0.05 to 2% by weight, in particular from 0.1 to 1% by weight, based on the total weight of the reactants, i.e. the intermediate formed in step a), the polyether of formula (II) and optionally the alcohol R8-OH, if present. Suitable Broenstedt catalysts include but are not limited to organic sulfonic acids, e.g. alkylsulfonic acids, such as methyl or ethylsulfonic acid and arylsulfonic acid such as phenylsulfonic acid or toluenesulfonic acid.

[0070] The reaction of step b) is frequently performed at temperatures in the range from 80 to 180°C, in particular from 90 to 160°C. Normally, the reaction of step b) will be performed at a pressure in the range from 900 to 1200 hPa.

[0071] It may be beneficial to remove volatiles, which are formed in the reaction, e.g. water and/or alcohol R4a-OH by distillation. In this regard, it may be beneficial to reduce the pressure at the end of the reaction, in order to facilitate destillative removal of the volatiles.

[0072] In process 2 of the invention 2,4,6-triamino-1,3,5-triazine, an aldehyde of the formula R3-CHO and the polyether of formula (II) are reacted. Preferred aldehydes are those, mentioned as preferred aldehydes for step a) of process 1. Particular preference is given to C2-C4-alkanals, especially to propanal.

[0073] The relative amount of aldehyde R3-CHO used in process 2 is frequently in the range from 0.25 to 3.0 mol, in particular from 0.3 to 2.5 mol, especially from 0.35 to 2.3 mol per mol of NH2-groups in the 2,4,6-triamino-1,3,5-triazine or from 0.75 to 9 mol, in particular from 0.9 to 7.5 mol, especially from 1.05 to 6.9 mol per mol of 2,4,6-triamino-1,3,5-triazine.

[0074] The amount of polyether of formula (II) used in process 2 will frequently be at least 10 mol-%, in particular at least 15 mol-% and especially at least 20 mol-% or at least 25 mol-% based on the total number of amino groups present in melamine used in process 2. The amount of polyether of formula (II) may be as high as 200 mol-% in particular up to 180 mol-%, based on the total number of amino groups present in melamine used in process 2. Frequently, it is in the range from 30 to 120 mol-%, based on the total number of amino groups present in melamine used in process 2.

[0075] Frequently, the amount of polyether of formula (II) used in the reaction of step b) will be at least 30 mol-%, in particular at least 45 mol-%, especially at least 60 mol-% or at least 75 mol-% of melamine used in process 2.

[0076] Frequently, the amount of polyether of formula (II) used in the reaction of process 2 will be in the range from 10 to 99% by weight, based on the total weight of melamine, aldehyde R3-CHO and polyether of formula (II). Preferably, the amount of polyether of formula (II) used in the reaction of process 2 will be in the range from 20 to 95% by weight, in particular from 30 to 90% by weight, based on the total weight of melamine, aldehyde R3-CHO and polyether of formula (II).

[0077] The reaction of process 2 is preferably performed in the presence of an acidic or a basic catalyst, preferably an acidic catalyst and in particular a Broenstedt acid catalyst. However, Lewis acid catalysts can also be used. The amount of catalyst is frequently in the range from 0.05 to 2% by weight, in particular from 0.1 to 1% by weight, based on the total weight of the reactants, i.e. the melamine, the aldehyde R3-CHO, the polyether of formula (II) and optionally the alcohol R8-OH, if present. Suitable Broenstedt catalysts include but are not limited to organic sulfonic acids, e.g. alkylsulfonic acids such as methyl or ethylsulfonic acid and arylsulfonic acid such as phenylsulfonic acid or toluenesulfonic acid.

[0078] Frequently, the reaction of process 2 is performed by mixing the aldehyde R3-CHO and melamine in the desired amount, optionally in a solvent, such as water or an alcohol R4a-OH, allow the mixture to react at moderate temperatures of at most 80°C, e.g. at the temperatures given for step a) of process 1, preferably in the absence of a catalyst, and than adding the polyether of the formula (II) and optionally a catalyst and heating the reaction mixture to a temperature of at least 80°C, in particular at least 90°C.

[0079] The reaction of process 2 is frequently performed at temperatures in the range from 80 to 180°C, in particular from 90 to 160°C. Normally, the reaction of process 2 will be performed at a pressure in the range from 900 to 1200 hPa.

[0080] It may be beneficial to remove volatiles, which are formed in the reaction, e.g. water or an excess of aldehyde R3-CHO, by distillation. In this regard, it may be beneficial to reduce the pressure at the end of the reaction, in order to facilitate destillative removal of the volatiles.

[0081] As described for step b) of process 1, a part of the polyether of formula (II) may be replaced by an alcohol of the formula R8-OH, where R8 is as defined above. However, the amount of the alcohol of the formula R8-OH will generally not exceed 50 mol-%, in particular 30 mol-%, based on the total amount of alcohol R8-OH and polyether of formula (II). If present, the amount of the alcohol of the formula R8-OH will frequently in the range from 1 to 50 mol-%, in particular from 5 to 30 mol-%, based on the total amount of alcohol R8-OH and polyether of formula (II). Preferably, no alcohol of formula R8-OH is present in the reaction of process 2.

[0082] Irrespectively of whether process 1 or process 2 is used, preference is given to polyethers of formula (II), wherein the variables A, x and R5 have the preferred meanings given herein for A, x and R5, especially those wherein
A
is ethan-1,2-diyl;
x
is an integer having a number average value in the range from 5 to 60, especially in the range from 5 to 30;
R5
is C1-C4-alkyl, especially methyl.


[0083] Examples of preferred polyethers of formula (II) are C1-C10-alkylpolyethylenoxides, C1-C10-alkylpolypropylenenoxides, and C1-C10-alkylpoly(ethylenoxide-co-propylenoxide), in particular C1-C4-alkylpolyethylenoxides, and especially methylpolyethylenoxides. Preferred are polyethers of formula (II), which have a number average weight in the range from 140 to 10,000, in particular in the range from 150 to 5,000, more particularly in the range from 200 to 2,000 and especially in the range from 250 to 1,250.

[0084] The mixtures of mono- or polynuclear melamine compounds as described herein, which can be prepared by one of the processes 1 or 2, are particularly useful as a dispersant for pigment materials in non-aqueous, liquid pigment compositions.

[0085] Therefore, the present invention relates to the use of mixtures of the mono- or polynuclear melamine compounds as described herein, which can be prepared by one of the processes 1 or 2, in non-aqueous pigment compositions, in particular in an non-aqueous concentrate pigment composition, i.e. in pigment pastes, which can be used for tinting or coloring non-aqueous coating compositions, in particular for coloring solvent-borne paint systems.

[0086] The present invention also relates to non-aqueous pigment compositions, comprising a mixture of mono- or polynuclear melamine compounds as described herein, which can be prepared by one of the processes 1 or 2, a pigment material and a non-aqueous liquid diluent.

[0087] The term "pigment materials", as used herein, includes both pigments and fillers. In the pigment composition of the invention, the pigment material is in particular selected from the group consisting of pigments and mixtures of at least one pigment and at least one filler. Pigments include organic pigments, inorganic pigments and luster pigments/perlescent flakes.

[0088] Examples of suitable organic pigments include azo pigments, disazo pigments, naphthol pigments, benzimidazolone pigments, disazocondensation pigments, metal complex pigments, isoindolinone pigments, isoindoline pigments, the chinophthalon pigments, dioxazine pigments and the polycyclic pigment group consisting of indigo, thioindigo, quinacridones, phthalocyanines, perylenes, perionones, anthraquinones, such as aminoanthraquinones or hydroxyanthraquinones, anthrapyrimidines, indanthrones, flavanthrones, pyranthrones, anthantrones, isoviolanthrones, diketopyrrolopyrrole, and carbazoles, e.g. carbazole violet, and the like. Further examples of organic pigments can be found in the monograph: W. Herbst, K. Hunger "Industrielle Organische Pigmente" 2nd Edition, 1995, VCH Verlagsgesellschaft, ISBN: 3-527-28744-2.

[0089] Representative examples of organic pigments are:
  • Monoazo pigments: C.I. Pigment Yellow 1, 3, 62, 65, 73, 74, 97, 183 und 191; C.I. Pigment Orange 5, 38 and 64; C.I. Pigment Red 1, 2, 3, 4, 5, 23, 48:1, 48:2, 48:3, 48:4, 49, 49:1, 51, 51:1, 52:1, 52:2, 53, 53:1, 53:3, 57:1, 58:2, 58:4, 63, 112, 146, 148, 170, 184, 187, 191:1, 210, 245, 247 and 251;
  • Disazo pigments: C.I. Pigment Yellow 12, 13, 14, 16, 17, 81, 83, 106, 113, 126, 127, 155, 170, 174, 176 and 188; C.I. Pigment Orange 16, 34 and 44;
  • Disazocondensation pigments: C.I. Pigment Yellow 93, 95 and 128; C.I. Pigment Red 144, 166, 214, 220, 221, 242 and 262; C.I. Pigment Brown 23 and 41;
  • Anthanthrone pigments: C.I. Pigment Red 168;
  • Anthrachinone pigments: C.I. Pigment Yellow 147 and 199; C.I. Pigment Red 177;
  • Anthrapyrimidine pigments: C.I. Pigment Yellow 108;
  • Benzimidazolone pigments: C.I. Pigment Yellow 120, 151, 154, 180, 181; C.I. Pigment Orange 36 and 72, C.I. Pigment Red 175, 185, 208; C.I. Pigment Brown 25; C.I. Pigment Violet 32;
  • Chinacridone pigments: C.I. Pigment Orange 48 and 49; C.I. Pigment Red 122, 202, 206 and 209; C.I. Pigment Violet 19;
  • Chinophthalone pigments: C.I. Pigment Yellow 138;
  • Diketopyrrolopyrrolpigmente: C.I. Pigment Orange 71, 73 and 81; C.I. Pigment Red 254, 255, 264, 270 and 272;
  • Dioxazine pigments: C.I. Pigment Violet 23;
  • Flavanthrone pigments: C.I. Pigment Yellow 24;
  • Indanthrone pigments: C.I. Pigment Blue 60 and 64;
  • Isoindoline pigments: C.I. Pigment Yellow 139 and 185; C.I. Pigment Orange 61 and 69, C.I. Pigment Red 260;
  • Isoindolinone pigments: C.I. Pigment Yellow 109, 110 and 173;
  • Isoviolanthrone pigments: C.I. Pigment Violet 31;
  • Metalcomplex pigments: C.I. Pigment Red 257; C.I. Pigment Yellow 117, 129, 150, 153 and 177; C.I. Pigment Green 8;
  • Perinone pigments: C.I. Pigment Orange 43; C.I. Pigment Red 194;
  • Perylene pigments: C.I. Pigment Red 123, 149, 178, 179 and 224; C.I. Pigment Violet 29; C.I. Pigment Black 31 and 32;
  • Phthalocyanin pigments: C.I. Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16; C.I. Pigment Green 7, 36;
  • Pyranthrone pigments: C.I. Pigment Orange 51; C.I. Pigment Red 216;
  • Pyrazolochinazolone pigments: C.I. Pigment Orange 67 and C.I. Pigment Red 216;
  • Thioindigo pigments: C.I. Pigment Red 88 and 181; C.I. Pigment Violet 38;
  • Triarylcarbonium pigments: C.I. Pigment Red 81, 81:1 and 169; C.I. Pigment Violet 1, 2, 3 and 27; C.I. Pigment Blue 1, 61 and 62; C.I. Pigment Green 1;
  • C.I. Pigment Black 1 (Aniline black);
  • C.I. Pigment Yellow 101 (Aldazine yellow);
  • C.I. Pigment Brown 22.


[0090] Suitable inorganic pigments are e.g.
  • white pigments, such as titanium dioxide (C.I. Pigment White 6) including crystal forms or modifications thereof, such as rutil or anatas, zinc oxide, zinc sulphide, zinc phosphate, lithopone;
  • black pigments: iron oxide black (C.I. Pigment Black 11), iron-manganese black, spinel black (C.I. Pigment Black 27); carbon black (C.I. Pigment Black 7); graphite (C.I. Pigment Black 10); chromium-iron-black (P.Brown 29);
  • inorganic colored pigments: chrome oxide, chrome oxide hydrate green; chrome oxide green (C.I. Pigment Green 48); cobalt green (C.I. Pigment Green 50); ultramarine greene; cobalt blue (C.I. Pigment Blue 28 und 36; C.I. Pigment Blue 72); ultramarine blue; blue manganese; ultramarine violet; cobalt- and manganese violet; red iron oxide (C.I. Pigment Red 101); cadmium sulfoselenides (C.I. Pigment Red 108); cerium sulfide (C.I. Pigment Red 265); molybdenum red (C.I. Pigment Red 104); ultramarine red; brown iron oxide (C.I. Pigment Brown 6 und 7), mixed brown, spinel phases and corundum phases (C.I. Pigment Brown 29, 31, 33, 34, 35, 37, 39 und 40), chromium titanium yellow (CI Pigment Brown 24), chrome orange; cerium sulfide (C.I. Pigment Orange 75); yellow iron oxide (CI Pigment Yellow 42); nickel titanium yellow (C.I. Pigment Yellow 53; C.I. Pigment Yellow 157, 158, 159, 160, 161, 162, 163, 164 und 189); Chromium titanium yellow; Spinel phases (CI Pigment Yellow 119);Cadmium sulfide and cadmium zinc sulfide (CI Pigment Yellow 37 and 35); Chrome yellow (CI Pigment Yellow 34); Bismuth vanadate (CI Pigment Yellow 184).


[0091] The luster pigments are single-phase or multi-phase construction lamellar pigments whose color play is characterized by the interplay of interference, reflection and absorption phenomena. Examples are aluminum platelets and one or more times, especially of metal oxides coated aluminum, iron oxide and mica platelets.

[0092] Suitable fillers are calcium carbonate, such as natural and precipitated chalksilicon dioxides, such as quartz powder and transparent silicon dioxide, silicates, talc, kaolin, natural and synthetic mica, barium sulphate, metal oxides and hydroxides, such as aluminium oxide and aluminium hydroxide.

[0093] The size of the pigment material is preferably in the micrometer range, e.g. the weight average particle diameter may range from 0.1 µm to 500 µm, in particular form 0.2 µm to 100 µm or from 0.5 µm to 50 µm. The weight average particle diameter is usually determined by light scattering methods, e.g. by the method of ISO 13320:2009. The weight average particle diameter may be also be determined by sieving analysis.

[0094] Generally, the non-aqueous pigment compositions of the invention contain 10 to 70% by weight, in particular 20 to 50% by weight, based on the total weight of the composition, of the pigment component.

[0095] In the aqueous pigment composition of the invention the weight ratio of pigment component to the mixture of mono- or polynuclear melamine compounds, calculated in each case as solids, is frequently in the range from 20:1 to 1:5, in particular from 10:1 to 1:2. The concentration of the mixture of mono- or polynuclear melamine compounds, calculated as solids and based on the total weight of the composition, is generally in the range from 1 to 30% by weight, in particular from 2 to 20% by weight.

[0096] The non-aqueous diluent present in the aqueous pigment composition of the invention will depend on the field of application in a known manner. Suitable diluents include organic solvents, such as C1-C6 alkanols, e.g. methanol, ethanol, isopropanol, propanol or n-butanol, ketones, such as di-C1-C4-alkyl ketones, such as acetone, methylethyl ketone, diethylketone, cyclic ketones, such as cyclohexanone, esters of aliphatic acids, in particular of acetic acid, such as ethyl acetate, butyl acetate, methoxyethylacetate, methoxypropyl acetate, aromatic hydrocarbons, such as toluene, xylenes, and aromatic distillates, aromatic ethers, such as anisole, glycol ethers like butyl glycol, or methoxypropylene glycol.

[0097] For preparing the pigment composition of the invention, the pigment component is usually dispersed in the non-aqueous diluent in the presence of a mixture of mono- or polynuclear melamine compounds. The dispersion can be achieved by using conventional techniques, such as high speed mixing, ball milling, sand grinding, attritor grinding or two or three roll milling. The resulting pigment composition may have a pigment to dispersant weight ratio in the above range.

[0098] Depending on the intended use, the pigment composition may further comprise one or more conventional additives depending on the intended use. Conventional additives included e.g. rheology additives, non-ionic dispersants, flow auxiliaries, defoamers, pigment synergists, preservatives, and the like.

[0099] The pigment composition is frequently formulated as a pigment paste. Such a pigment paste contains the pigment component, the dispersant composition of the invention and an aqueous diluent and optionally additives but generally it will not contain binders.

[0100] The pigment compositions of the invention provide for good application properties, such as high color strength, good dispersability in a multitude of liquid compositions. They are particularly useful for tinting solvent borne coating compositions. The resulting paints have high color strength and do not show color change in the rub out-test, as described in DE 2202527.

[0101] Suitable coating compositions which can be colored with the pigment compositions of the invention include architectural coatings, industrial coatings, automotive coatings, radiation-curable coatings; paints, including paints for building exteriors and building interiors, for example wood paints, lime washes, distempers and emulsion paints. They can also be used for coloring solventborne printing inks, for example offset printing inks, flexographic printing inks, toluene gravure printing inks, textile printing inks, radiation-curable printing inks; waterborne inks, including inkjet inks and color filters.

[0102] As explained above, the pigment composition may be included into a coating composition. Such a coating composition contains the pigment component, the mixture of mono- or polynuclear melamine compounds, a non-aqueous liquid diluent and additionally one or more binders, e.g. film-forming polymers or prepolymers which form a film upon curing. Coating composition may optionally contain conventional additives conventionally used in coating technology, e.g. plasticisers, lubricants, emulsifiers, rheology additives, catalysts, flow auxiliaries, optical brighteners, flame retardants, preservatives, antistatic agents or blowing agents.

[0103] Suitable binders are the ones customarily used, for example the ones described in Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition, Vol. A 18, pp. 368-426, VCH, Weinheim 1991, Germany. In general, the film-forming binder is based on a thermoplastic or thermosetting resin, predominantly on a thermosetting resin. Examples thereof are alkyd, acrylic, polyester, phenolic, melamine, epoxy and polyurethane resins and mixtures thereof. Also resins curable by radiation or air-drying resins can be used. Binders may also be derived from polyvinylalcohol and polyvinylbutyral.

[0104] If cold- or hot-curable binders are used, the addition of a curing catalyst may be advantageous. Suitable catalysts that accelerate the curing of binders are described, for example, in Ullmann's, Vol. A18, loc. cit., p. 469.

[0105] Examples of coating compositions containing cold- or hot-curable binders are:
  • Paints based on cold- or hot-cross linkable alkyd, acrylate, polyester, epoxy or melamine resins or mixtures of such resins, if desired with addition of a curing catalyst;
  • Two-component polyurethane paints based on hydroxyl-containing acrylate, polyester or polyether resins and aliphatic or aromatic isocyanates, isocyanurates or polyisocyanates;
  • One-component polyurethane paints based on blocked isocyanates, isocyanurates or polyisocyanates which are deblocked during baking, if desired with addition of a melamine resin;
  • One-component polyurethane paints based on a trisalkoxycarbonyl triazine cross linker and a hydroxyl group containing resin, such as acrylate, polyester or polyether resins;
  • One-component polyurethane paints based on aliphatic or aromatic urethane acrylates or polyurethane acrylates having free amino groups within the urethane structure and melamine resins or polyether resins, if necessary with curing catalyst;
  • Two-component paints based on (poly)ketimines and aliphatic or aromatic isocyanates, isocyanurates or polyisocyanates;
  • Two-component paints based on (poly)ketimines and an unsaturated acrylate resin or a polyacetoacetate resin or a methacrylamidoglycolate methyl ester;
  • Two-component paints based on carboxyl- or amino-containing polyacrylates and polyepoxides;
  • Two-component paints based on acrylate resins containing anhydride groups and on a polyhydroxy or polyamino component;
  • Two-component paints based on acrylate-containing anhydrides and polyepoxides;
  • Two-component paints based on (poly) oxazolines and acrylate resins containing anhydride groups, or unsaturated acrylate resins, or aliphatic or aromatic isocyanates, isocyanurates or polyisocyanates;
  • Two-component paints based on unsaturated polyacrylates and polymalonates;
  • Thermoplastic polyacrylate paints based on thermoplastic acrylate resins or externally cross linking acrylate resins in combination with etherified melamine resins; and
  • Paint systems based on siloxane-modified or fluorine-modified acrylate resins.


[0106] The invention is hereinafter also described by way of examples.

[0107] The following abbreviations will be used
AN:
Amine Number [mg KOH/g]
b.w.:
by weight
EO:
ethyleneoxide
Eq.:
equivalents
Mn.:
number average molecular weight
SB:
Solvent-borne
SC:
Solid content
VA:
visual appearance

Preparation example: Propanal based melamine resin (intermediate PM)



[0108] In a 600 ml four necked flask, 54.0 g of melamine were suspended in 149.2 g of 1-propanal. The mixture was heated to 40°C and stirred for one hour. Then, 300 g of methanol were added, and the solution was stirred at 65°C until it became clear. The excess methanol was removed under vacuum until a viscous mass was left in the reactor. To this ethanol was added at 60°C and then the obtained mixture was cooled to 5°C. Thereby, a precipitate was filtered off and dried in an oven yielding 109 g of a white powder (∼ 65% yield of theory).

Examples 1 to 3:



[0109] A 250 ml four necked flask, was charged at 22°C with intermediate PM of the preparation example, polyether alcohol and 0.5% by weight (based on total amount of both reactants) of para-toluene sulfonic acid. Ingredients and molar ratios based on reactive methylethers of the melamine resin were used according to the table 1 below.

[0110] The reaction mass was heated to 110°C, and methanol was removed from the reactor under slight vacuum (ca. 800 mbar). The reaction was completed once no further methanol was collected in the receptor flask (duration ca. 6 hours). The final products were obtained as clear yellowish to orange liquids and used as such. Reactants, reaction conditions and properties of the obtained products are given in the following table 1. The following polyethers were used

A1: methoxypolyethylene glycol with Mn 500

A2: methoxypolyethylene glycol with Mn 350

A3: C10-Oxoalcohol with 7 EO

Table 1
ExamplePMAlcohols (weight)Time [h]AN [mg KOH/g]SC [%]VA
1 25.0 g A2 4 h 64,6 97,2 Yellow clear liquid
47 g
2 15.0 g A1 5 h 50.5 99,5 Yellow clear liquid
40.3 g
3 11.0 g A3 5 h 52.7 99,9 orange slightly turbid liquid at 22°C
27,6 g

Example 4:



[0111] Into a 2 l four necked flask, melamine (75.7 g) and 1-propanal (232.3 g) were added and stirred at 45°C for 30 min. Then 840 g of methoxypolyethylene glycol with Mn 350 and 4.8 g of para-toluene sulfonic acid were added and stirred under reflux for another 3 hours. The volatiles were removed by vacuum distillation (500 mbar, max 110°C). The resulting product (958 g) was obtained as a colorless clear liquid with a solid content of >95%.

Application test:



[0112] To reflect the broad applicability of the melamine compounds of the invention on all pigment classes, the dispersants compositions were formulated as pigment pastes with a representative selection of pigments. The following pigments were employed:
  • Blue pigment: Heliogen® Blue L 6700 F - Cu-phthalocyanine pigment of BASF SE;
  • Red pigment: Bayferrox® Red 130M - micronized iron oxide pigment of Lanxess;
  • Black pigment: Carbon Black FW 200 - a small sized carbon black pigment of Evonik Industries.


[0113] For comparative purposes, the following commercial pigment dispersants were used:
Dispersant 1:
Efka® PX 4310 (Benchmark): Dispersant based on Acrylate monomers, 70 % solution in Methoxypropylacetate
Dispersant 2:
Efka® PX 4330: Dispersant based on Acrylate monomers, 70% solution in Methoxypropylacetate

A) Trials with pigment pastes with different Dispersing Agents in SB Alkyd-melamine system:



[0114] The pigment pastes were prepared by mixing the respective amount of pigment, dispersant, and the respective amount of butylglycol to obtain 100 g total weight according to table 2. Additionally 2 mm glass beads were added in a 1:1 weight ratio. After dispersing the paste for 2-4 h in a "DAS 200 Disperser" from LAU, the glass beads were removed by filtration. Pigment loading and weight ratio of dispersant/pigment is given in in table 2:
Table 2
 Blue 1 1)Blue 2Red 1 1)Red 2Black 1 1)Black 2
Butyl glycol 73 63.8 29.7 22.7 80.1 75.7
Dispersant 2) 7.0   5.3   4.9  
Example 43)   16.2   12.3   9.3
Blue pigment 20 20        
Red pigment     65 65    
Black pigment         15 15
Total 100 100 100 100 100 100
1) Comparative examples
2) Conventional dispersant, (70% solution in butanol)
3) Inventive dispersant (30% solution in butanol)


[0115] After equilibration of the pigment pastes for minimum 12 h, their viscosity was determined with an "Anton Paar MCR 302" rheometer at 22°C and a shear rate of 1 s-1 with a cone-plate geometry.

[0116] After adding the pigment paste to a solvent borne alkyd-melamine high-gloss finish (parts b.w. of pigment paste per 20 parts b.w. of SB high gloss finish), the finish was applied to a metal substrate by draw down. After drying of the coating the color strength were measured by a "Konica Minolta 2600D" colorimeter. In the following table 3 the values are given relative to a benchmark (dispersant 1) which is defined as 100%.
Table 3
 20% Heliogen® Blue L 6700 F65% Bayferrox® Red 130M15% Carbon Black FW 200
Dispersing AgentViscosityColor strengthViscosityColor strengthViscosityColor strength
Dispersant 1* low 100% very low 100% very high 100%
Dispersant 2* low 98% very low 77% very high 76%
Example 4 low 101% low 96% low 90%
* Comparative

B) Trials with pigment pastes with different Dispersing Agents in SB Resin Containing Acrylic system, based on Joncryl® 507 and 588:



[0117] The coating compositions were prepared by mixing the respective amount of pigment, dispersant, resin binder and the respective amount of solvent to obtain 100 g total weight according to table 4. Additionally 2 mm glass beads were added in a 1:1 weight ratio. After dispersing the paste for 4 h in a "DAS 200 Disperser" from LAU, the glass beads were removed by filtration.

[0118] Joncryl® 507 and Joncryl® 588 are hydroxyl functional acrylic binders.
Table 4
 Black 1 1)Black 2
Joncryl® 507 12.5 12.5
Joncryl® 588 12.8 12.8
n-Butanol 3 2.5
Dispersant 2) 10.5  
Example 4 3)   24.5
n-Butyl acetate 49.2 35.7
Black pigment 12 12
Total 100 100
1) Comparative examples
2) Conventional dispersant, 70% solution
3) Inventive dispersant, 30% solution


[0119] Viscosity and color strength were assessed as described above. The results are summarized in table 5.
Table 5
 12% Carbon Black FW 200
Dispersing AgentViscosityColor strength
Dispersant 1* low 100%
Dispersant 2* low 88%
Example 4 low 101%
* Comparative



Claims

1. A mixture of mono- or polynuclear melamine compounds, which have at least one 2,4,6-triamino-1,3,5-triazine ring, wherein at least one amino group of at least one of the 2,4,6-triamino-1,3,5-triazine rings is of the formula A:

        NR1R2     (A)

where

R1 is H, CH(R3)OR4 or R2,

R2 is CH(R3)O(A-O)x-R5, where

R3 is H, C1-C10-alkyl or aryl,

R4 is H, C1-C4-alkyl or C1-C4-alkoxy-C1-C4-alkyl,

R5 is a hydrocarbon radical having from 1 to 40 carbon atoms, which is selected from C1-C22-alkyl, aryl-C1-C4-alkyl or aryl, where aryl in the last two mentioned radicals is phenyl or naphthyl, which is unsubstituted or carries 1 or 2 C1-C10-alkyl groups;

x is an integer from 2 to 500, having a number average value in the range from 3 to 200;

A is an C2-C4-alkan-1,2-diyl radical;

where the mono- or polynuclear melamine compounds are selected from mononuclear melamine compounds of the formula (M1), binuclear polynuclear melamine compounds of the formula (M2) and polynuclear melamine compounds of the formulae (M3),





where in formula M1
at least one of the radicals A1, A2 and A3 is a radical of the formula (A), while the remaining radicals are of the formulae NHRx or NRxRy, respectively
where in formula M2
at least one of the radicals A1, A2, A4 and A5 is a radical of the formula (A), while the remaining radicals A1, A2, A4 and/or A5 are of the formulae NHRx or NRxRy, respectively,
L is a bivalent linker CH(R3) or CH(R3)[O-CH(R3)]k, where k is an integer, which is in the range from 1 to 5, and
A33 and A34 are radicals NRz,
and
where in formula M3
at least one of the radicals A6, A7 and A8 is a radical of the formula Ma

wherein p is 0 or an integer from 1 to 20, provided that in at least one of the groups Ma the variable p is different from 0,

# indicates the point of attachment to the triazine ring of M3,

L and L' are identical or different bivalent linkers as defined for L in formula M2, A33, A34, A35 and A36 are radicals NRz,

provided at least one of the radicals A2, A4, A5, A6, A7 and A8 is a radical of the formula (A), while the remaining radicals A2, A4 and A5, are of the formulae NHRx or NRxRy, respectively, and the remaining radicals A6 and A7, are of the formulae Ma, NHRx or NRxRy, respectively,

and where

Rx is CH(R3)OR4 or CH(R3)O-R8,

Ry is CH(R3)OR4 or CH(R3)O-R8,

Rz is hydrogen, CH(R3)OR4 or CH(R3)O-R8, and

R8 is a hydrocarbon radical having from 5 to 40 carbon atoms.


 
2. The mixture of claim 1, where in formula (A)

A is selected from the group consisting of ethan-1,2-diyl and propan-1,2-diyl and combinations thereof.


 
3. The mixture of claim 2, where in formula (A)

A is ethan-1,2-diyl;

x is an integer having a number average value in the range from 5 to 60;

R5 is C1-C4-alkyl, especially methyl.


 
4. The mixture of any one of the preceding claims, where in formula (A) the radical R1 is hydrogen.
 
5. The mixture of any one of the preceding claims, wherein at least one 2,4,6-triamino-1,3,5-triazine rings bears an amino group of the formula B:

        NR6R7     (B)

where

R6 is H or CH(R3)OR4,

R7 is CH(R3)O-R8, where

R3 is H, C1-C10-alkyl or aryl,

R4 is H, C1-C4-alkyl or C1-C4-alkoxy-C1-C4-alkyl,

R8 is a hydrocarbon radical having from 5 to 40 carbon atoms.


 
6. The mixture of claim 5, where in formula (B) the radical R6 is hydrogen and the radical R8 is C8-C20-alkyl or C8-C20-alkenyl.
 
7. The mixture of any one of the preceding claims, where the radicals O(A-O)x-R5 present in the melamine compounds amount to 20 to 95% by weight, based on the total weight of the melamine compound and/or where on average at least 10 mol-% of the amino groups of the 2,4,6-triamino-1,3,5-triazine ring are of the formula A.
 
8. The mixture of any one of the preceding claims, which is characterized by at least one of the following features i) or ii):

i) in the context of formulae (A) and (B) the radical R3 is C1-C4-alkyl, especially ethyl;

ii) the melamine compounds have a weight average molecular weight in the range of 520 to 120000.


 
9. A process for preparing a mixture of melamine compounds of any one of the preceding claims, which comprises

a) reacting 2,4,6-triamino-1,3,5-triazine and an aldehyde of the formula R3-CHO and optionally an alcohol R4a-OH, wherein R3 is as defined above and R4a has one of the meanings given for R4 except for hydrogen;

b) reacting the reaction product of step a) with a polyether of formula (II)

        R5-[O-A]xOH     (II)

wherein R5, A and x are as defined in any one of claims 1, 2 or 3;
or
which comprises reacting a polyether of formula (II)

        R5-[O-A]xOH     (II)

wherein R5, A and x are as defined in any one of claims 1, 2 or 3,

with 2,4,6-triamino-1,3,5-triazine and an aldehyde of the formula R3-CHO and optionally an alcohol R4a-OH or R8-OH, wherein R3 and R8 are as defined in one of claims 1, 5 or 6 and R4a has one of the meanings given for R4 except for hydrogen.


 
10. The process of claim 9, where the reaction with the polyether of formula (II) is performed in the presence of catalytic amounts of a Broensted acid and/or where the amount of polyether of formula (II) is from 20 to 95% by weight, based on the total weight of polyether of formula (II), aldehyde of formula R3-CHO and 2,4,6-triamino-1,3,5-triazine.
 
11. The mixture of any of claims 1 to 8 prepared by the process of claim 9 or 10.
 
12. The use of a mixture of melamine compounds of any one of claims 1 to 8 and 11 as a dispersant in non-aqueous, liquid pigment compositions.
 
13. Non-aqueous pigment composition, comprising a mixture of melamine compounds of any one of claims 1 to 8 and 11, a pigment component, selected from the group consisting of pigments and mixtures of at least one pigment and at least one filler, and a non-aqueous diluent.
 
14. The non-aqueous pigment composition of claim 13, which is a pigment paste and/or where the weight ratio of pigment component to the mixture of melamine compounds, calculated in each case as solids, is in the range from 20:1 to 1:1, in particular from 10:1 to 2:1.
 
15. The use of pigment composition of any of claims 13 or 14 as a colorant in solvent-borne coating compositions.
 


Ansprüche

1. Gemisch aus ein- oder mehrkernigen Melamin-Verbindungen, die mindestens einen 2,4,6-Triamino-1,3,5-triazin-Ring aufweisen, wobei mindestens eine Aminogruppe von mindestens einem der 2,4,6-Triamino-1,3,5-triazin-Ringe die Formel A aufweist:

        NR1R2     (A)

wobei

R1 für H, CH(R3)OR4 oder R2 steht,

R2 für CH(R3)O(A-O)x-R5 steht, wobei

R3 für H, C1-C10-Alkyl oder Aryl steht,

R4 für H, C1-C4-Alkyl oder C1-C4-Alkoxy-C1-C4-alkyl steht,

R5 für einen Kohlenwasserstoffrest mit 1 bis 40 Kohlenstoffatomen steht, der ausgewählt ist aus C1-C22-Alkyl, Aryl-C1-C4-alkyl oder Aryl, wobei Aryl in den zwei letztgenannten Resten für Phenyl oder Naphthyl steht, das unsubstituiert ist oder 1 oder 2 C1-C10-Alkyl-Gruppen trägt;

x eine ganze Zahl von 2 bis 500 ist, mit einem zahlenmittleren Wert im Bereich von 3 bis 200;

A für einen C2-C4-Alkan-1,2-diyl-Rest steht;

wobei die ein- oder mehrkernigen Melamin-Verbindungen ausgewählt sind aus einkernigen Melamin-Verbindungen der Formel (M1), zweikernigen mehrkernigen Melamin-Verbindungen der Formel (M2) und mehrkernigen Melamin-Verbindungen der Formel (M3),







wobei in Formel M1
mindestens einer der Reste A1, A2 und A3 für einen Rest der Formel (A) steht, wobei die verbleibenden Reste die Formel NHR× bzw. NRxRy aufweisen,
wobei in Formel M2
mindestens einer der Reste A1, A2, A4 und A5 für einen Rest der Formel (A) steht, während die verbleibenden Reste A1, A2, A4 und/oder A5 die Formel NHR× bzw. NRxRy aufweisen,
L für eine zweiwertige Verbindungsgruppe CH(R3) oder CH(R3)[O-CH(R3)]k steht, wobei k für eine ganze Zahl steht, die im Bereich von 1 bis 5 liegt, und
A33 und A34 für Reste NRz stehen
und
wobei in Formel M3 mindestens einer der Reste A6, A7 und A8 für einen Rest der Formel Ma steht

wobei p für 0 oder eine ganze Zahl von 1 bis 20 steht, mit der Maßgabe, dass in mindestens einer der Gruppen Ma die Variable p von 0 verschieden ist,

# die Bindungsstelle mit dem Triazin-Ring von M3 anzeigt, L und L' für identische oder verschiedene zweiwertige Verbindungsgruppen entsprechend der Definition für L in Formel M2 stehen,

A33, A34, A35 und A36 für Reste NRz stehen,

mit der Maßgabe, dass mindestens einer der Reste A2, A4, A5, A6, A7 und A8 für einen Rest der Formel (A) steht, wobei die verbleibenden Reste A2, A4 und A5 die Formel NHR× bzw. NRxRy aufweisen und die verbleibenden Reste A6 und A7 die Formel Ma, NHRx bzw. NRxRy aufweisen,

und wobei

Rx für CH(R3)OR4 oder CH(R3)O-R8 steht,

Ry für CH(R3)OR4 oder CH(R3)O-R8 steht,

Rz für Wasserstoff, CH(R3)OR4 oder CH(R3)O-R8 steht und

R8 für einen Kohlenwasserstoffrest mit 5 bis 40 Kohlenstoffatomen steht.


 
2. Gemisch nach Anspruch 1, wobei in Formel (A) A ausgewählt ist aus der Gruppe bestehend aus Ethan-1,2-diyl und Propan-1,2-diyl und Kombinationen davon.
 
3. Gemisch nach Anspruch 2, wobei in Formel (A) A für Ethan-1,2-diyl steht;
x für eine ganze Zahl mit einem zahlenmittleren Wert im Bereich von 5 bis 60 steht;
R5 für C1-C4-Alkyl, insbesondere Methyl, steht.
 
4. Gemisch nach einem der vorstehenden Ansprüche, wobei in Formel (A) der Rest R1 für Wasserstoff steht.
 
5. Gemisch nach einem der vorstehenden Ansprüche, wobei mindestens ein 2,4,6-Triamino-1,3,5-triazin-Ring eine Aminogruppe der Formel B aufweist:

        NR6R7     (B)

wobei

R6 für H oder CH(R3)OR4 steht,

R7 für CH(R3)O-R8 steht, wobei

R3 für H, C1-C10-Alkyl oder Aryl steht,

R4 für H, C1-C4-Alkyl oder C1-C4-Alkoxy-C1-C4-alkyl steht,

R8 für einen Kohlenwasserstoffrest mit 5 bis 40 Kohlenstoffatomen steht.


 
6. Gemisch nach Anspruch 5, wobei in Formel (B) der Rest R6 für Wasserstoff steht und der Rest R8 für C8-C20-Alkyl oder C8-C20-Alkenyl steht.
 
7. Gemisch nach einem der vorstehenden Ansprüche, wobei die Reste O(A-O)x-R5, die in den Melamin-Verbindungen vorhanden sind, 20 bis 95 Gew.-% ausmachen, bezogen auf das Gesamtgewicht der Melamin-Verbindung, und/oder wobei im Durchschnitt mindestens 10 Mol-% der Aminogruppen des 2,4,6-Triamino-1,3,5-triazin-Rings die Formel A aufweisen.
 
8. Gemisch nach einem der vorstehenden Ansprüche, gekennzeichnet durch mindestens eines der folgenden Merkmale i) oder ii):

i) im Zusammenhang mit den Formeln (A) und (B) steht der Rest R3 für C1-C4-Alkyl, insbesondere Ethyl;

ii) die Melamin-Verbindungen weisen ein gewichtsmittleres Molekulargewicht im Bereich von 520 bis 120000 auf.


 
9. Verfahren zum Herstellen eines Gemischs aus Melamin-Verbindungen nach einem der vorstehenden Ansprüche, umfassend:

a) Umsetzen von 2,4,6-Triamino-1,3,5-triazin und einem Aldehyd der Formel R3-CHO und gegebenenfalls einem Alkohol R4a-OH, wobei R3 der obigen Definition entspricht und R4a eine der für R4 angegebenen Bedeutungen hat, außer Wasserstoff;

b) Umsetzen des Reaktionsprodukts von Schritt a) mit einem Polyether der Formel (II)

        R5-[O-A]xOH     (II)

wobei R5, A und x der Definition in einem der Ansprüche 1,2 oder 3 entsprechen;
oder
umfassend ein Umsetzen eines Polyethers der Formel (II)

        R5-[O-A]xOH     (II)

wobei R5, A und x der Definition in einem der Ansprüche 1,2 oder 3 entsprechen, mit 2,4,6-Triamino-1,3,5-triazin und einem Aldehyd der Formel R3-CHO und gegebenenfalls einem Alkohol R4a-OH oder R8-OH, wobei R3 und R8 der Definition in einem der Ansprüche 1, 5 oder 6 entsprechen und R4a eine der für R4 angegebenen Bedeutungen hat, außer Wasserstoff.


 
10. Verfahren nach Anspruch 9, wobei die Reaktion mit dem Polyether der Formel (II) in Anwesenheit katalytischer Mengen einer Brønsted-Säure durchgeführt wird und/oder wobei die Menge an Polyether der Formel (II) bei 20 bis 95 Gew.-% liegt, bezogen auf das Gesamtgewicht von Polyether der Formel (II), Aldehyd der Formel R3-CHO und 2,4,6-Triamino-1,3,5-triazin.
 
11. Gemisch nach einem der Ansprüche 1 bis 8, hergestellt durch das Verfahren nach Anspruch 9 oder 10.
 
12. Verwendung eines Gemischs aus Melamin-Verbindungen nach einem der Ansprüche 1 bis 8 und 11 als Dispersionsmittel in nichtwässrigen flüssigen Pigmentzusammensetzungen.
 
13. Nichtwässrige Pigmentzusammensetzung, umfassend ein Gemisch aus Melamin-Verbindungen nach einem der Ansprüche 1 bis 8 und 11, eine Pigmentkomponente, die ausgewählt ist aus der Gruppe bestehend aus Pigmenten und Gemischen aus mindestens einem Pigment und mindestens einem Füllstoff, und ein nichtwässriges Verdünnungsmittel.
 
14. Nichtwässrige Pigmentzusammensetzung nach Anspruch 13, bei der es sich um eine Pigmentpaste handelt und/oder wobei das Gewichtsverhältnis der Pigmentkomponente zu dem Gemisch aus Melamin-Verbindungen, jeweils als Feststoffe berechnet, im Bereich von 20:1 bis 1:1, insbesondere von 10:1 bis 2:1, liegt.
 
15. Verwendung von Pigmentzusammensetzungen nach einem der Ansprüche 13 oder 14 als Färbemittel in lösemittelhaltigen Beschichtungszusammensetzung.
 


Revendications

1. Mélange de composés de mélamine mono- ou polynucléaires, qui comportent au moins un cycle 2,4,6-triamino-1,3,5-triazine, dans lequel au moins un groupe amino d'au moins un des cycles 2,4,6-triamino-1,3,5-triazine est de formule A :

        NR1R2     (A)

R1 est H, CH(R3)OR4 ou R2,

R2 est CH(R3)O(A-O)x-R5, où

R3 est H, alkyle en C1-C10 ou aryle,

R4 est H, alkyle en C1-C4 ou (alcoxy en C1-C4)-(alkyle en C1-C4),

R5 est un radical hydrocarboné ayant de 1 à 40 atomes de carbone, qui est choisi parmi alkyle en C1-C22, aryl-(alkyle en C1-C4) ou aryle, où aryle dans les deux derniers radicaux mentionnés est phényle ou naphtyle, qui est non substitué ou porte 1 ou 2 groupes alkyle en C1-C10 ;

x est un entier de 2 à 500, ayant une valeur moyenne en nombre dans la plage de 3 à 200 ;

A est un radical (alcane en C2-C4)-1,2-diyle ;

où les composés de mélamine mono- ou polynucléaires sont choisis parmi des composés de mélamine mononucléaires de formule (M1), des composés de mélamine polynucléaires binucléaires de formule (M2) et des composés de mélamine polynucléaires de formule (M3),





où, dans la formule M1
au moins l'un des radicaux A1, A2 et A3 est un radical de formule (A), tandis que les radicaux restants sont de formules NHRx ou NRxRy, respectivement
où, dans la formule M2
au moins l'un des radicaux A1, A2, A4 et A5 est un radical de formule (A), tandis que les radicaux A1, A2, A4 et/ou A5 restants sont de formules NHRX ou NRxRy, respectivement, L est un lieur bivalent CH(R3) ou CH(R3)[O-CH(R3)]k, où k est un entier, qui est dans la plage de 1 à 5, et
A33 et A34 sont des radicaux NRz,
et
où, dans la formule M3
au moins l'un des radicaux A6, A7 et A8 est un radical de formule Ma

dans laquelle p est 0 ou un entier de 1 à 20, à condition que, dans au moins un des groupes Ma, la variable p soit différente de 0,

# indique le point de liaison au cycle triazine de M3,

L et L' sont des lieurs bivalents identiques ou différents tels que définis pour L dans la formule M2, A33, A34, A35 et A36 sont des radicaux NRz,

à condition qu'au moins l'un des radicaux A2, A4, A5, A6, A7 et A8 soit un radical de formule (A), tandis que les radicaux restants A2, A4 et A5, sont de formules NHRX ou NRxRy, respectivement, et les radicaux A6 et A7 restants sont de formules Ma, NHRx ou NRxRy, respectivement,

et où

Rx est CH(R3)OR4 ou CH(R3)O-R8,

Ry est CH(R3)OR4 ou CH(R3)O-R8,

Rz est hydrogène, CH(R3)OR4 ou CH(R3)O-R8, et

R8 est un radical hydrocarboné ayant de 5 à 40 atomes de carbone.


 
2. Mélange selon la revendication 1, où, dans la formule (A)
A est choisi dans le groupe constitué d'éthane-1,2-diyle et propane-1,2-diyle et des combinaisons de ceux-ci.
 
3. Mélange selon la revendication 2, où, dans la formule (A)
A est éthane-1,2-diyle ;
x est un entier ayant une valeur moyenne en nombre dans la plage de 5 à 60 ;
R5 est alkyle en C1-C4, en particulier méthyle.
 
4. Mélange selon l'une quelconque des revendications précédentes, où, dans la formule (A), le radical R1 est hydrogène.
 
5. Mélange selon l'une quelconque des revendications précédentes, dans lequel au moins un cycle 2,4,6-triamino-1,3,5-triazine porte un groupe amino de formule B :

        NR6R7     (B)

R6 est H ou CH(R3)OR4,

R7 est CH(R3)O-R8, où

R3 est H, alkyle en C1-C10 ou aryle,

R4 est H, alkyle en C1-C4 ou (alcoxy en C1-C4)-(alkyle en C1 -C4),

R8 est un radical hydrocarboné ayant de 5 à 40 atomes de carbone.


 
6. Mélange selon la revendication 5, où, dans la formule (B), le radical R6 est hydrogène et le radical R8 est alkyle en C8-C20 ou alcényle en C8-C20.
 
7. Mélange selon l'une quelconque des revendications précédentes, où les radicaux O(A-O)X-R5 présents dans les composés de mélamine représentent 20 à 95 % en poids, sur la base du poids total des composés de mélamine et/ou dans lequel, en moyenne, au moins 10 % en moles des groupes amino du cycle 2,4,6-triamino-1,3,5-triazine sont de formule A.
 
8. Mélange selon l'une quelconque des revendications précédentes, qui est caractérisé par au moins l'une des caractéristiques i) ou ii) suivantes :

i) dans le contexte des formules (A) et (B), le radical R3 est alkyle en C1-C4, en particulier éthyle ;

ii) les composés de mélamine ont un poids moléculaire moyen en poids dans la plage de 520 à 120 000.


 
9. Procédé de préparation d'un mélange de composés de mélamine selon l'une quelconque des revendications précédentes, qui comprend

a) la réaction de 2,4,6-triamino-1,3,5-triazine et d'un aldéhyde de formule R3-CHO et facultativement d'un alcool R4a-OH, où R3 est tel que défini ci-dessus et R4a a l'une des significations données pour R4 sauf hydrogène ;

b) la réaction du produit de réaction de l'étape a) avec un polyéther de formule (II)

        R5-[O-A]XOH     (II)

dans laquelle R5, A et x sont tels que définis dans l'une quelconque des revendications 1, 2 ou 3 ;
ou
qui comprend la réaction d'un polyéther de formule (II)

        R5-[O-A]XOH     (II)

dans laquelle R5, A et x sont tels que définis dans l'une quelconque des revendications 1, 2 ou 3,
avec la 2,4,6-triamino-1,3,5-triazine et un aldéhyde de formule R3-CHO et facultativement un alcool R4a-OH ou R8-OH, où R3 et R8 sont tels que définis dans l'une des revendications 1, 5 ou 6 et R4a a l'une des significations données pour R4 sauf hydrogène.


 
10. Procédé selon la revendication 9, où la réaction avec le polyéther de formule (II) est conduite en présence de quantités catalytiques d'un acide de Brönsted et/ou dans lequel la quantité de polyéther de formule (II) est de 20 à 95 % en poids, sur la base du poids total de polyéther de formule (II), d'aldéhyde de formule R3-CHO et de 2,4,6-triamino-1,3,5-triazine.
 
11. Mélange selon l'une quelconque des revendications 1 à 8, préparé par le procédé selon la revendication 9 ou 10.
 
12. Utilisation d'un mélange de composés de mélamine selon l'une quelconque des revendications 1 à 8 et 11 en tant que dispersant dans des compositions de pigment liquides, non aqueuses.
 
13. Composition de pigment non aqueuse, comprenant un mélange de composés de mélamine selon l'une quelconque des revendications 1 à 8 et 11, un composant de pigment, choisi dans le groupe constitué de pigments et de mélanges d'au moins un pigment et d'au moins une charge, et un diluant non aqueux.
 
14. Composition de pigment non aqueuse selon la revendication 13, qui est une pâte de pigment et/ou dans laquelle le rapport en poids de composant de pigment au mélange de composés de mélamine, calculé dans chaque cas en solides, est dans la plage de 20:1 à 1:1, en particulier de 10:1 à 2:1.
 
15. Utilisation d'une composition de pigment selon l'une quelconque des revendications 13 ou 14 en tant que colorant dans des compositions de revêtement à base de solvant.
 






Cited references

REFERENCES CITED IN THE DESCRIPTION



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Patent documents cited in the description




Non-patent literature cited in the description