(19)
(11)EP 3 666 869 A1

(12)EUROPEAN PATENT APPLICATION

(43)Date of publication:
17.06.2020 Bulletin 2020/25

(21)Application number: 18211210.2

(22)Date of filing:  10.12.2018
(51)International Patent Classification (IPC): 
C11D 3/12(2006.01)
C11D 7/20(2006.01)
C11D 17/06(2006.01)
C11D 3/40(2006.01)
C11D 17/00(2006.01)
(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
Designated Extension States:
BA ME
Designated Validation States:
KH MA MD TN

(71)Applicant: Clariant Plastics & Coatings Ltd
4132 Muttenz (CH)

(72)Inventor:
  • The designation of the inventor has not yet been filed
     ()

(74)Representative: Jacobi, Carola 
Clariant Produkte (Deutschland) GmbH Patent & License Management Chemicals Industriepark Höchst, G 860
65926 Frankfurt
65926 Frankfurt (DE)

  


(54)AN ENCAPSULATED DYE COMPOSITION AND A METHOD FOR PREPARATION THEREOF


(57) The present invention relates to an encapsulated dye composition and a method for preparation thereof. The encapsulated dye composition of the present disclosure is found to be non-bleeding encapsulated dye. The encapsulated dye composition comprises a carrier consisting of a mixture of silica and clay, and a dye encapsulated in the carrier. The encapsulated dye optionally comprises a binder.


Description

FIELD OF INVENTION



[0001] The present invention relates to an encapsulated dye composition for detergent powder. In particular the present invention relates to non-bleeding dye composition encapsulated in a carrier, method for the preparation of said encapsulated dye composition and detergent compositions comprising the same.

BACKGROUND OF INVENTION



[0002] Incorporation of the colored pigments in the detergent powder has increased for the past few years. The colored particles enhance the appearance of the detergent powder, as well as may have effect on the fabric conditioning.

[0003] The colored particles used in the detergent powder mostly comprise of the colorant such as dye. The use of dye stuff as colored material is associated with flaws. Conventionally used colored particles tend to bleed the dye in the detergent powder and therefore tend to convert the colour of the white powder. This may affect the customer base for that particular detergent powder.

[0004] Additionally, the dye gets stuck in the fabric and does not shed off the fabric thereby affecting the fabrics.

[0005] US-20110053823 discloses colored speckles comprising a porous material, a releasing agent, and a dye. This patent describes the colored speckles which quickly release color from the porous carrier using releasing agent and provide desirable color to the wash water. The releasing agent is selected from the group consisting of salt compounds, sugar compounds, alkoxylated aromatic compounds, glycols, high molecular weight alcohols, solvents having a boiling point above 60°C, and mixtures thereof.

[0006] WO-0210327 discloses colored speckles comprising sodium chloride and colorant. It discloses presence of significant amount of hygroscopic material i.e. sodium chloride (at least 90%) in the matrix. This could cause the bleeding of dye in powder detergent under humidity in storage.

[0007] To overcome the disadvantages associated with the prior art, the present disclosure provides the encapsulated dye composition that does not bleed in the detergent powder and shed off the fabric easily during washing.

SUMMARY OF INVENTION



[0008] According to an aspect the invention provides an encapsulated dye composition comprising a dye, a carrier consisting of a mixture of silica and clay and optionally a binder.

[0009] In another aspect the present invention provides methods for the preparation of the encapsulated dye composition.

[0010] According to another aspect the present invention provides a detergent composition comprising encapsulated dye composition of the present invention.

[0011] According to another aspect the present invention provides a method of laundering fabrics which includes a step of treating the fabrics with encapsulated dye composition of present invention.

DETAILED DESCRIPTION OF INVENTION



[0012] For the purposes of the following detailed description, it is to be understood that the invention may assume various alternative variations and step sequences, except where expressly specified to the contrary. Moreover, other than in any operating examples, or where otherwise indicated, all numbers expressing, for example, quantities of ingredients used in the specification are to be understood as being modified in all instances by the term "about". It is noted that, unless otherwise stated, all percentages given in this specification and appended claims refer to percentages by weight of the total composition.

[0013] Thus, before describing the present invention in detail, it is to be understood that this invention is not limited to particularly exemplified process parameters that may of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments of the invention only, and is not intended to limit the scope of the invention in any manner.

[0014] The use of examples anywhere in this specification including examples of any terms discussed herein is illustrative only, and in no way limits the scope and meaning of the invention or of any exemplified term. Likewise, the invention is not limited to various embodiments given in this specification.

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0016] Weight percentages (wt.% or %wt) herein are calculated based upon total weight of the composition, unless otherwise indicated.

[0017] It must be noted that, as used in this specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the content clearly dictates otherwise.

[0018] The terms "preferred" and "preferably" refer to embodiments of the invention that may afford certain benefits, under certain circumstances. However, other embodiments may also be preferred, under the same or other circumstances.

[0019] Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the invention.

[0020] As used herein, the terms "comprising" "including," "having," "containing," "involving," and the like are to be understood to be open-ended, i.e., to mean including but not limited to.

[0021] In one aspect of the present invention, there is provided an encapsulated dye composition comprising:
  1. a) a carrier material consisting of a mixture of silica and clay; and
  2. b) at least one dye entrapped in the carrier.


[0022] The encapsulated composition of the present invention further comprises a binder such as a surfactant or a polymer. Suitable surfactant includes nonionic, anionic, cationic or amphoteric surfactants. Examples of suitable nonionic surfactants are polyoxyethylene sorbitan esters, polyoxyethylene sorbitol esters, polyoxyalkylene fatty alcohol ethers, polyoxyalkylene fatty acid esters, alkoxylated glycerides, polyoxyethylene methyl glucoside ester, alkyl polyglucosides, EO-PO blockpolymers or combinations of two or more thereof.

[0023] Examples of anionic surfactants are sulfonates of alkylbenzene-sulfonates, alkanesulfonates, olefinsulfonates, alkyl ether sulfate, alkyl sulfate, sulfo-succinates, alkyl phosphates, alkyl ether phosphates, protein fatty acid condensates, perferably collagen hydrolysates modified with fatty acid, amino acid-based surfactants, isethionates, taurides, acyl lactylates, neutralized fatty acids or combinations of two or more thereof.

[0024] Examples of cationic surfactants are esterquats, ditallow dimethyl ammonium chloride, C12/14 alkyl dimethyl benzyl ammonium chloride, alkyl dimethyl benzil ammonium chloride, cetyl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, behenyl trimethyl ammonium chloride alkyl hydroxyethyl dimethyl ammonium chloride, distearyl dimethyl ammonium chloride, dihydrogenated tallow fatty alkyl dimethyl ammonium chloride or combinations of two or more thereof. Examples of amphoteric surfactants are alkyl amphoacetate, alkyl amidopropyl betaine, alkyl amidopropyl dimethylamine betaine, undecylenamidopropyl betaine, alkyl dimethyl amine oxide.

[0025] Examples of polymers are cellulosic polymers such as hydroxyl propyl methyl cellulose (HPMC), carboxy methyl cellulose (CMC); polyvinyl alcohol (PVA) polymers:polyvinyl acetate (PVAc) polymer and any combinations thereof. Optionally TiO2 dispersion may be added to enhance whiteness.

[0026] In an embodiment of the present invention, the binder is hydroxyl propyl methyl cellulose (HPMC).

[0027] In an embodiment of the present invention, the dye is selected from the group consisting of azine dye for example anionic azine dye, cationic phenazine dye; triarylmethane dyes for example triphenyl-methane dye; anthraquinone dye; azo dye, disazo dye; phthalocyanine dye; quinophthalone dye; methine dye; hemicyanine dye; azo/azomethine complex dye; triphendioxazine dye or a mixture thereof.

[0028] In an embodiment the dye is selected from the group consisting of Duasyn Acid Violet 4BN-IN (C.I. Acid Violet 17), Duasyn Violet SP-IN (C.I. Direct Violet 66), Duasyn Red N-6B-IN (C.I. Acid Violet 54), Duasyn Violet FBL-IN (C.I. Acid Violet 48), Duasyn Red Violet E2R-IN (C.I. Acid Violet 126) or mixtures of one or several of the afore mentioned dyes.

[0029] In an embodiment, the silica is at least one selected from a silica gel, pyrogenic silica and precipitated silica.

[0030] In an embodiment the precipitated silica is hydrophilic precipitated silica, hydrophobic precipitated silica or a mixture of both. Precipitated silica is typically produced by a precipitation of a sodium silicate with a mineral acid under neutral or slightly alkaline conditions. For the final application the filter cake of precipitated silica is dried and ground. Hydrophilic silica adsorbs water around the dye and hydrophobic silica does not allow water to get into touch with dye.

[0031] In an embodiment of the present invention, the silica is hydrophilic precipitated silica.

[0032] The hydrophilic silica only consists of SiO2 and does not exhibit any surface modification and is wettable by water.

[0033] In a preferred embodiment of the present invention, the hydrophilic silica has a particle size d50 determined by laser diffraction of at least 50 µm, preferably at least 70 µm, mostly preferred at least 90 µm.

[0034] The precipitated silica is selected from the group consisting of Sipernat® 22; Sipernat® 50 from Evonik Industries, Ibersil® D 100 or Ibersil® D100P form the IGE Group, Flo-Gard® SC-72, Flo-Gard® LPC from PPG. The precipitated silica of the inventive formulation is characterized by a high liquid absorption capacity, determined as DOA absorption number of at least 120 ml/100g, preferably at least 140 ml/100g, mostly preferred at least 160 ml/100g precipitated silica. DOA is the abbreviation for di-(2-ethylhexyl) adipate (CAS-number 103-23-1). The test method is based on ISO 19246 ("Rubber compounding ingredients- Silica - Oil absorption of precipitated silica").

[0035] Hydrophobic silica is not wettable by water and exhibits an organic surface modification created by chemical reactions with reactive alkylsilanes. The existence of such a surface modification can be proven by various analytical methods, e.g. the carbon content in an elemental analyzer following ISO 3262-19. In an embodiment the precipitated silica or one of the precipitated silica used in the formulations has a hydrophobic surface.

[0036] The hydrophobic precipitated silica for the inventive formulation is characterized by a particle size d50 determined by laser diffraction (laser diffraction based on ISO 13320) of at least 5 µm, preferably at least 7 µm, mostly preferred at least 9 µm.

[0037] In an embodiment the hydrophilic silica is Sipernat® D17 (d50 -10 micron) or Sipernat® D10 (particle size -d50 -6.5 micron, free flowable) or combinations thereof.

[0038] As used herein, the term "clay" refers to both natural clays as well as modified clays. Modified clays in this context refers to natural clays which have been alkaline-activated or acid-activated. As used herein, the terms "clay minerals' or "special clay minerals" refer to natural clays.

[0039] In an embodiment the clay used in the present composition is selected from the group consisting of natural clays comprising bentonite, montmorillonite, beidellite, saponite, hectorite, stevensite, kerolite-saponite, kerolite, talc, pyrophyllite, attapulgite, sepiolite; a mixture of natural silica with a bentonite;any modified clays; and any mixtures thereof..

[0040] In an embodiment of the present invention, the clay is bentonite.

[0041] In another aspect of the present disclosure, there is provided an encapsulated dye composition comprising:
  1. a) a carrier consisting of a mixture of silica and clay
  2. b) a binder and
  3. c) dye
wherein said dye is encapsulated in the carrier.

[0042] In an embodiment, the dye is used in the amount in the range of 1% to 30%, based on the total weight of the encapsulated dye composition, preferably 5% to 20%.

[0043] In an embodiment, the binder is used in the amount of 1 to 5% based on the total weight of the encapsulated dye composition.

[0044] In an embodiment, the silica is used in the amount of 30% to 75% based on the total weight of the encapsulated dye composition.

[0045] In an embodiment, the clay is used in the amount of 30% to 75 % based on the total weight of the encapsulated dye composition.
In an embodiment, the carrier has a silica to clay ratio of 1:4 to 4:1.
In an embodiment the present invention provides an encapsulated dye composition comprising:
  1. a) a carrier comprising 30% to 75% by weight of silica and 30% to 75% by weight of clay
  2. b) 1 to 5% by weight of binder and
  3. c) 1 to 20% by weight of dye
wherein said dye is encapsulated in the carrier.

[0046] The clay consisting of a smectite like a bentonite, beidellite, saponite, hectorite, stevensite, kerolite-saponite,is employed in the natural Ca-form or in a soda activated form.

[0047] In another embodiment natural sodium bentonite is used as clay. Especially preferred clays are montmorillonites in the natural or soda activated form or mixtures thereof.

[0048] In an embodiment the clay used is bentonite having cation exchange capacity in the range of 10 meq/100 g to 140 meq/100g.

[0049] In an embodiment the clay used is bentonite having cation exchange capacity in the range of 20 meq/100 g to 130 meq/100g, preferably between 30 meq/100 g to 120 meq/100 g.

[0050] In an embodiment a special clay mineral is used, which consists of a mixture of smectite clay and an amorphous silica phase. The clay material is homogenous on a macroscopic scale, i.e.it is an intimate mixture of both phases.

[0051] The special clay mineral used has a very high silicon content which is well above the silicon content of e.g. bentonite. The clay mineral does not have such a well ordered structure as layered silicates, e.g. bentonite, but preferably comprises large amounts of amorphous material. Such amorphous material is believed to be formed by amorphous SiO2.

[0052] The special clay mineral of the present invention comprises a continuous phase of amorphous silica into which are inserted small platelet-shaped smectite phases. The platelets of the smectite phase are homogeneously distributed in the continuous amorphous silica phase and are firmly fixed therein.

[0053] The special clay mineral of the present invention comprises a matrix-like network of amorphous SiO2 into which very small clay particles are inserted and which may provide good protection of the dye to be encapsulated.

[0054] In one embodiment, the clay mineral of the present invention has a very high surface area in the range of 180 to 300 m2/g, preferably 185 to 280 m2/g, and more preferably 190 to 250 m2/g as determined by the BET method.

[0055] In an embodiment the clay mineral of the present invention has high total pore volume of more than 0.5 ml/g.

[0056] In an embodiment the clay mineral of the present invention has total pore volume of more than 0.55 ml/g, preferably more than 0.6 ml/g.

[0057] Inventors believe, the large pore volume of the clay mineral allows rapid access of the dye particles or molecules to the pores, in which they are protected. The special clay mineral comprises a matrix of amorphous SiO2 into which are inserted small particles of smectite minerals. The smectite particles are delaminated to a high degree and therefore provide a very high surface area.

[0058] Through the large pores provided in the clay mineral, which are in particular situated in the SiO2-matrix, a rapid access of the dye to the clay particles inserted in the SiO2-matrix is possible throughout the absorption process as the clay material does hardly swell during adsorption of dye.

[0059] In an embodiment the clay mineral used comprise a rigid, amorphous SiO2 matrix into which are inserted very small clay particles or platelets.

[0060] Preferably, the clay mineral used in the method according to the invention comprises an amorphous phase of at least 10 wt.% of the total clay mineral, preferably at least 20 wt.%, more preferably at least 30 wt.% .

[0061] In an embodiment of the invention, the amorphous phase forms less than 90 wt.% of the total clay mineral.

[0062] In another embodiment of the invention, the amorphous phase forms less than 80 wt.% of the clay mineral.

[0063] Besides the amorphous phase, the clay mineral used in the method of the invention preferably comprises a smectite phase. The clay mineral preferably comprises less than 60 wt.%, more preferred less than 50 wt.%, particularly preferred less than 40 wt.% of a smectite phase.

[0064] According to an embodiment of the invention, the smectite phase forms at least 10 wt.%, according to a further embodiment at least 20 wt.% of the clay mineral.

[0065] In an embodiment the ratio of smectite phase to amorphous phase preferably is within a range of 2 to 0.5, more preferred 1.2 to 0.8.

[0066] Besides the amorphous phase and the smectite phase further minerals may be present in the clay mineral, preferably within a range of 0.5 to 40 wt.%, more preferred 1 to 30 wt.%, particularly preferred 3 to 20 wt.%. Exemplary side minerals are quartz, cristobalite, feldspar and calcite. Other side minerals may also be present.

[0067] In accordance with the present invention, the matrix of the clay mineral, preferably formed from silica gel dilutes the smectite phase which leads, depending on the fraction of the smectite phase, to a lowering of the signal-to-noise ratio of typical reflections of smectite minerals e.g. the small angle reflections of montmorillonite are effected by the periodic distance between layers of the montmorillonite structure. Further, the clay particles fixed in the SiO2-matrix are delaminated to a very high degree leading to a strong broadening of the corresponding diffraction peak.

[0068] The amount of amorphous silica phase and smectite clay phase present in the clay mineral can be determined by quantitative X-ray-diffraction analysis. Details of such method are described e.g. in "Hand Book of Clay Science", F. Bergaya, B.K.G. Therry, G. Lagaly (Eds.), Elsevier, Oxford, Amsterdam, 2006, Chapter 12.1: I. Srodon, Identification and Quantitative Analysis of Clay Minerals; "X-Ray Diffraction and the Identification and Analysis of Clay Minerals", D.M. Moora and R.C. Reaynolds, Oxford University Press, New York, 1997, pp 765, included herein by reference.

[0069] For application of this method to the analysis of mineral samples, one can refer to e.g. D.K. McCarthy "Quantitative Mineral Analysis of Clay-bearing Mixtures", in: "The Reynolds Cup" Contest. IUCr CPD Newsletter, 27, 2002, 12 - 16.

[0070] The quantitative determination of the different minerals in unknown samples is done by commercially available software, e.g. "Seifert AutoQuan" available from Seifert/GE Inspection Technologies, Ahrensburg, Germany.

[0071] The XRD-diffractogram of the clay mineral of the present invention exhibit the reflexes which are hardly visible above noise.

[0072] In an embodiment of the present invention, the signal to noise ratio for reflexes of the clay mineral, in particular the smectite phase, is close to 1, preferably in the range of 1 to 1.2. However, the sharp reflexes may be visible in the diffractogram originating from impurities in the clay mineral, e.g. quartz. Such reflexes are not considered for determination of the signal/noise ratio.

[0073] In an embodiment, the clay mineral of the present invention, which does not or does hardly show a 001 reflection indicating the layer distance within the crystal structure of bentonite particles. Hardly visible means that the signal-to-noise ratio of the 001 reflection of the smectite particles is preferably less than 1.2, particularly preferred is within a range of 1.0 to 1.1.

[0074] Preferably the clay mineral has a sediment volume in water after 1 hour of less than 15 ml/2g, more preferred of less than 10 ml/2g and most preferred of less than 7 ml/2g.

[0075] In an embodiment the clay mineral of the present invention, in particular when mined from a natural source, preferably has a cation exchange capacity of more than 40 meq/100 g, particularly preferred of more than 45 meq/100 g and is most preferred selected within a range of 44 to 120 meq/100 g.

[0076] In an embodiment high activity bleaching earth obtained by extracting a clay mineral with boiling strong acid is characterized by a very low cation exchange capacity of usually less than 40 meq/100 g and in most cases of less than 30 meq/100g.

[0077] The modified clay used in the method according to the invention therefore can clearly be distinguished from such high performance bleaching earth.

[0078] In an embodiment the clay of the present invention is characterized by a high content of SiO2 determined after complete disintegration of the clay being above 62 wt.%, preferably above 64 wt.%, especially preferred above 66 wt.%. Besides silicon other preferred metals or metal oxides may be contained in the clay. All percentages refer to a dry clay material dried to constant weight at 105°C.

[0079] The claypreferably has a low aluminium content of, calculated as Al2O3, less than 15 wt.%, more preferred of less than 10 wt.%. The aluminium content, calculated as Al2O3, according to an embodiment is more than 2 wt.%, according to a further embodiment more than 4 wt.%.

[0080] In an embodiment the clay contains magnesium, calculated as MgO, in an amount of less than 7 wt.%, preferably of less than 6 wt.%, particularly preferred less than 5 wt.%. In one embodiment, the magnesium content is at least 2 wt.%

[0081] In an embodiment the clay contains iron, calculated as Fe2O3, in amount of less than 8 wt.%. According to a further embodiment, the iron content, calculated as Fe2O3, may be less than 6 wt.% and according to a still further embodiment may be less than 5 wt.%. According to a further embodiment, the clay may contain iron, calculated as Fe2O3, in an amount of at least 1 wt.%, and according to a still further embodiment in an amount of at least 2 wt.%.

[0082] In an embodiment the present invention provides encapsulation of shading dyes comprising forming an encapsulation matrix consisting of mixture of silica for example hydrophilic silica or hydrophobic silica, clay, dye and binding agent for example surfactant or polymers to obtain stable encapsulated dye composition.

[0083] In another aspect the present invention provides method for the preparation of the encapsulated dye composition.

[0084] The method for preparation of encapsulated dye composition comprises
  1. a) mixing a dye with a carrier to obtain a mixture;
  2. b) adding water to the mixture to obtain a semisolid mass;
  3. c) extruding the semisolid mass to obtain extrudates;
  4. d) spheronizing the extrudates to obtain granules; and
  5. e) coating the granules with a binder to obtain the encapsulated dye composition.


[0085] In an embodiment, the encapsulated dye composition can be in the powder form or in granular form.

[0086] The coating of the granules with the binder can be carried out by the conventionally known processes.

[0087] In the process of the present invention, the dye is entrapped in the carrier matrix by simple physical mixing resulting in slightly powder material. Alternatively, granules are formed by compaction or granulation or by extrusion or by using fluidized bed processing. The granules thus formed have particle size -400 to 600 microns. Optionally, the resulting particles can be treated in additional step with liquid barrier materials like surfactants, aqueous solution of thickening polymers etc.

[0088] The resulting encapsulated dye matrix is not bleeding the dye in powder detergent. Thus, it is not impacting white powder detergent color. The encapsulated dye is released in water as desired during the washing cycle.

[0089] In another embodiment the method for preparation of encapsulated dye composition comprises
  1. a) mixing the dye with the binder to obtain a mixture.
  2. b) blending the mixture with silica and clay as carrier to obtain the encapsulated dye composition.


[0090] In an embodiment the process comprises encapsulation of shading dye Duasyn Acid Violet 4BN-IN (C.I. Acid Violet 17), Duasyn Violet SP-IN (C.I. Direct Violet 66), Duasyn Red N-6B-IN (C.I. Acid Violet 54), Duasyn Violet FBL-IN (C.I. Acid Violet 48), Duasyn Red Violet E2R-IN (C.I. Acid Violet 126) or mixtures of one or several of the afore mentioned dye.

[0091] In another embodiment the dye is suspended in water or used as press cake and is blended or absorbed on silica and bentonite blends to achieve white dye encapsulated powder.

[0092] Typically, the process for preparation of encapsulated dye composition comprises mixing about 5-20% of dye with binder for example 1-5% of polymer or surfactant and blending this mixture with silica for example Sipernat® D17 optionally followed by addition of about 5 to 30% of silica for example Ibersil® D100P. The mixture is then blended thoroughly and the binder is added. The clay bentonites for example 20-40% of Laundrosil DGA and EXM 0242 is added to the blended mixture which will absorb on the shading dye loaded silica particles to give the encapsulated dye composition. This process involves manual/physical mixing of all the ingredients.

[0093] In another embodiment the process for preparation of encapsulated dye composition comprises fluidized bed coating process to obtain encapsulated matrix of at least one suitable dye, silica, bentonite and binders which provides spherical particles having particle size of ∼ 500 micron. Preferably, dye is mixed with silica for example Sipernat ® 22 and clay in required composition, followed by addition of water to make dough. The dough is then extruded using extruder and spheronised to prepare granules. The spheronised granules are further coated using Fluidized Bed Processer with suitable binding or coating polymers such as Hydroxy Propyl Methyl Cellulose (HPMC), Carboxy methyl cellulolse (CMC), Polyvinyl alcohol (PVA), polyvinyl acetate (PVAc), and optionally TiO2 dispersion for whiteness.

[0094] In accordance with the present invention the encapsulated dye composition comprises a carrier consisting of a mixture of silica and clay, a dye encapsulated in the carrier and optionally a binder. The encapsulated dye of the present disclosure is found to be stable and did not leave stains on the fabric during the washing.

[0095] Surprisingly, the encapsulated dye composition, when used in the detergent powder does not bleed into the powder and therefore it does not affect the white color of the detergent powder. Additionally, the encapsulated dye composition is released in water within few seconds with gentle stirring and can be easily shed off the clothes during washing.

[0096] In another aspect the present invention provides a detergent composition comprising encapsulated dye composition comprising:
  1. a) a carrier comprising 30% to 75% by weight of silica and 20% to 40% by weight of clay
  2. b) 1 to 5% by weight of binder and
  3. c) 1 to 20% by weight of dye


[0097] According to another aspect the present invention provides a method of laundering fabrics which includes a step of treating the fabrics with detergent composition comprising the encapsulated dye composition which comprising:
  1. a) a carrier comprising 30% to 75% by weight of silica and 20% to 40% by weight of clay
  2. b) 1 to 5% by weight of binder and
  3. c) 1 to 20% by weight of dye


[0098] The following examples are provided to better illustrate the present invention and are not to be interpreted in any way as limiting the scope of the invention. All specific compositions, materials, and methods described below, in whole or in part, fall within the scope of the invention. These specific compositions, materials, and methods are not intended to limit the invention, but merely to illustrate specific embodiments falling within the scope of the invention. One skilled in the art may develop equivalent compositions, materials, and methods without the exercise of inventive capacity and without departing from the scope of the invention. It will be understood that many variations can be made in the procedures herein described while still remaining within the bounds of the invention. It is the intention of the inventors that such variations are included within the scope of the invention.

EXAMPLES



[0099] Following examples disclose various encapsulated dye composition of the present invention and comparative dye compositions as comparative examples.

Materials and methods:



[0100] Different clays used in the present invention were characterized as follows.

[0101] The physical features used to characterize the adsorbents were ddetermined as follows:
(i) Specific surface and pore volume:
Specific surface and pore volume was determined by the BET-method (single-point method using nitrogen, according to DIN 66131) with an automatic nitrogen-porosimeter of Micrometrics, type ASAP 2010. The pore volume was determined using the BJH-method (E.P. Barrett, L.G. Joyner, P.P. Hienda, J. Am. Chem. Soc. 73 (1951) 373). Pore volumes of defined ranges of pore diameter were measured by summing up incremental pore volumina, which were determined from the adsorption isotherm according BJH. The total pore volume refers to pores having a diameter of 2 to 350 nm. The measurements provide as additional parameters the micropore surface, the external surface and the micropore volume. Micropores refer to pores having a pore diameter of up to 2 nm according to Pure & Applied Chem. Vol. 51, 603 - 619 (1985).
(ii) Humidity:
The amount of water present in the clay material at a temperature of 105°C was determined according to DIN/ISO-787/2.
(iii) Silicate analysis/Analysis of the chemical composition (expressed in terms of SiO2 and metal oxides):

a) Sample disintegration: A 10 g sample of the clay material was comminuted to obtain a fine powder which was dried in an oven at 105°C until constant weight. About 1.4 g of the dried sample was deposited in a platinum bowl and the weight is determined with a precision of 0.001 g. Then the sample was mixed with a 4 to 6-fold excess (weight) of a mixture of sodium carbonate and potassium carbonate (1:1). The mixture was placed in the platinum bowl into a Simon-Müller-oven and molten for 2 to 3 hours at a temperature of 800 - 850°C. The platinum bowl was taken out of the oven and cooled to room temperature. The solidified melt was dissolved in distilled water and transferred into a beaker. Then concentrated hydrochloride acid was carefully added. After evolution of gas has ceased the water was evaporated such that a dry residue was obtained. The residue was dissolved in 20 ml of concentrated hydrochloric acid followed by evaporation of the liquid. The process of dissolving in concentrated hydrochloric acid and evaporation of the liquid was repeated one time. The residue was then moistened with 5 to 10 ml of aqueous hydrochloric acid (12 %). About 100 ml of distilled water was added and the mixture was heated. To remove insoluble SiO2, the sample was filtered and the residue remaining on the filter paper was thoroughly washed with hot hydrochloric acid (12 %) and distilled water until no chlorine was detected in the filtrate. The clay material was totally disintegrated. After dissolution of the solids the compounds were analyzed and quantified by specific methods, e.g. ICP

b) Determination of the SiO2 content
The SiO2 was incinerated together with the filter paper and the residue was weighed.

c) Determination of aluminium, iron, calcium and magnesium
The filtrate was transferred into a calibrated flask and distilled water was added until the calibration mark. The amount of aluminium, iron, calcium and magnesium in the solution was determined by FAAS.

c) Determination of potassium, sodium and lithium
A 500 mg sample was weighed in a platinum bowl with a precision of 0.1 mg. The sample was moistened with about 1 to 2 ml of distilled water and then four drops of concentrated sulphuric acid were added. About 10 to 20 ml of concentrated hydrofluoric acid was added and the liquid phase evaporated to dryness in a sand bath. This process was repeated three times. Finally H2SO4 was added to the dry residue and the mixture was evaporated to dryness on an oven plate. The platinum bowl was calcined and, after cooling to room temperature, 40 ml of distilled water and 5 ml hydrochloric acid (18 %) was added to the residue and the mixture was heated to boiling. The solution was transferred into a calibrated 250 ml flask and water was added up to the calibration mark. The amount of sodium, potassium and lithium in the solution was determined by EAS.

(iv) Loss on ignition
In a calcined and weighed platinum bowl, about 0.1 g of a sample was deposited weighed in a precision of 0.1 mg. The sample was calcined for 2 hours at 1000°C in an oven. Then the platinum bowl was transferred to an exsiccator and weighed.
(v) Ion Exchange capacity
The clay material to be tested was dried at 150°C for two hours. Then the dried material was allowed to react under reflux with a large excess of aqueous NH4Cl solution for 1 hour. After standing at room temperature for 16 hours, the material was filtered. The filter cake was washed, dried, and ground, and the NH4 content in the clay material was determined by the Kjedahl method. The amount and kind of the exchanged metal ions was determined by ICP-spectroscopy.
g) Determination of the sediment volume:
A graduated 100 ml glass cylinder was filled with 100 ml of distilled water or with an aqueous solution of 1 % sodium carbonate and 2 % trisodium polyphosphate. 2 g of the compound to be analyzed was placed on the water surface in portions of about 0.1 to 0.2 g. After sinking down of a portion, the next portion of the compound was added. After adding 2 g of the compound to be analyzed the cylinder was held at room temperature for one hour. Then the sediment volume (ml/2g) was read from the graduation.
h) Determination of montmorillonite proportion by methylene blue adsorption

Preparation of a tetrasodium diphosphate solution
5.41 g tetrasodium diphosphate was weighed with a precision of 0.001 g in a calibrated 1000 ml flask and the flask was filled up to the calibration mark with distilled water and shaken repeatedly.

Preparation of a 0.5 % methylene blue solution:

In a 2000 ml beaker, 125 g methylene blue was dissolved in about 1500 ml distilled water. The solution was decanted and then distilled water was added up to a volume of 25 l.

0.5 g moist test bentonite having a known inner surface were weighed in an Erlenmeyer flask with a precision of 0.001 g. 50 ml tetrasodium diphosphate solution were added and the mixture was heated to boiling for 5 minutes. After cooling to room temperature, 10 ml H2SO4 (0.5 m) and 80 to 95 % of the expected consumption of methylene blue solution were added. With a glass stick a drop of the suspension was transferred to a filter paper. A blue-black spot was formed surrounded by a colourless corona. Further methylene blue solution was added in portions of 1 ml and the drop test was repeated until the corona surrounding the blue-black spot shows a slightly blue colour, i.e. the added methylene blue was no longer adsorbed by the test bentonite.

i) Analysis of clay materials
The test of the clay material was performed in the same way as described for the test bentonite. On the basis of the spent methylene blue solution was calculated the inner surface of the clay material. According to this method 381 mg methylene blue/g clay correspond to a content of 100 % montmorillonite.
j) Determination of particle size (dry sieve residue)
Through a sieve cloth, a vacuum cleaner connected with the sieve aspirates over a suction slit circling under the perforated sieve bottom all particles being finer than the inserted sieve being covered on top with an acrylic glass cover and leaves the coarser particles on the sieve.
The experimental procedure was as follows: Depending on the product, between 5 and 25 g of air dried material was weighed in and was put on the sieve. Subsequently, the acrylic glass cover was put on the sieve and the machine was started. During air jet screening, the screening process can be facilitated by beating on the acrylic glass cover using the rubber hammer. Exhaustion time was between 1 and 5 minutes. The calculation of the dry screening residue in % is as follows: actual weight multiplied with 100 and divided by the initial weight.
k) Apparent weight
A calibrated 1l glass cylinder cut at the 1000 ml mark was weighed. By a powder funnel the sample was poured into the cylinder in a single step such that the cylinder is completely filled and a cone was formed on top of the cylinder. The cone was removed with help of a ruler and material adhering to the outside of the cylinder was removed. The filled cylinder was weighed again and the apparent weight was obtained by subtracting the weight of the empty cylinder.
l) X-Ray-Diffraction Analysis
1 to 2 g of clay sample was dry ground by hand in an agate mortar and then passed through a 20 µm sieve. This process was repeated until the entire sample passed the sieve. For the X-ray diffraction measurement a Siemens D5000 equipment was used. The following measuring conditions were employed:
Sample holder Plastic, "top loading", Ø = 25 mm
Thickness of the powder layer 1 mm
X-ray tube Cu Kα: 40 kV/40mA
Diffraction angles 2 - 80 ° (2 θ)
Measuring time 3 sec per step
Slits Primary and secondary divergence slits of 1 mm


[0102] Qualitative evaluation of the diffractograms (assignment of the mineral phase was done with a computer program "EVA" by Bruker AXS GmbH, Karlsruhe and according to the publication of Brindley & Brown (1980): Crystal structures of clay minerals and their x-ray identification. - Mineralogical Society No. 5, 495.

[0103] The quantitative evaluation was made according to the Rietveld method as described above.

Characterization data:



[0104] The clay 1 and 2 namely Bentonite 1 (Laundrosil® DGA powder) is produced from Bentonite 2 by alkaline activation) and the clay, Bentonite 2 is a natural calcium/sodium bentonite (EX 0242, from Clariant). Both bentonites powder exhibit a dry sieve residue of less than 15 wt.% on sieve, with a mesh size of 45 µm.
The following tables show the typical properties of the Bentonite 1 and 2.
Table 1
 Bentonite 1Bentonite 2
Montmorillonite content, determined with the Methylene-blue method [%] 78 75
Cation exchange capacity [meq/100 g] 72 76
Fraction of monovalent ions of the total cation exchange capacity 100 20
Swelling volume in distilled water[ml/2 g) > 15 11
Side mineral content determined by X-ray diffraction See below See below
Quarz < 1 wt.% < 1 wt.%
Cristobalite < 5 wt.% < 5 wt.%
Feldspar < 12 wt.% < 12 wt.%


[0105] Characterization details of Clay 3-5 (Clays with High content of SiO2/Mixed phase of bentonite and natural Silica) is provided in below table. Clay 3 is sold under the brand name Tonsil® Supreme 118 FF.
Table 2
Clay345
Dry sieve residue on 45 µm (%) 49 55 5.2
Dry sieve residue on 63 µm (%) 35 40 38
apparent weight (g/l) 292 468 --
Methylene blue adsorption (mg/g sample) 106 152 179
Moisture content (%) 8 13 12
pH (10 wt.% in water) 7.6 9 8.1
cation exchange capacity (meq/100 g) 52 44 53.3
BET surface (m2/g) 208.4 238 248
micropore area (m2/g) 32.1 40 15
external surface (m2/g) 176.3 198 233
micropore volume (cm3/g) 0.016 0.02 0.01
cumulative pore volume (BJH) for pore diameter 1.7 - 300 nm (cm3/g) 0.825 0.623 0.777
average pore diameter (BJH) (nm) 16.4 10.0 55
sediment volume (ml/2g) 5.5 3 4


[0106] The chemical composition of the adsorbents in clay is summarized in table 3.
Table 3
Clay345
SiO2 70.6 wt.% 69.4 wt.% 69.4 wt.%
Fe2O3 2.8 wt.% 3.4 wt.% 3.4 wt.%
Al2O3 9.8 wt.% 9.9 wt.% 9.9 wt.%
MgO 4.1 wt.% 3.1 wt.% 3.1 wt.%
CaO 1.4 wt.% 2.5 wt.% 2.5 wt.%
K2O 1.5 wt.% 1.3 wt.% 1.3 wt.%
Na2O 0.26 wt.% 0.94 wt.% 0.94 wt.%
TiO2 0.25 wt.% 0.38 wt.% 0.38 wt.%
SO3 -- -- --
Loi (1000 °C) 7.9 wt.% 8.1 wt.% 8.1 wt.%

X-ray diffraction



[0107] X-ray diffraction measurements of clay were made according to the general description for the method. The results of quantitative mineral phase determination by X-ray diffraction are listed in table 4.
Table 4
Mineral Phase (wt.%)Clay 4Clay 5
Smectite 40 40
Illite / Muscovite Traces n.d.
Kaolinite n.d. 1
Sepiolite 11 n.d.
Quartz Traces 1
Orthoclase 12 8
Plagioclase (different) 3 11
Calcite Traces 1
Amorphous material 34 38


[0108] The quantitative X-ray diffraction analysis shows presence of smectite clay in clay 1 and 2 which are used in the method according to the invention.

[0109] In addition various side minerals can be found, like sepiolite for clay 1, orthoclase, plagioclase (other feldspars) and calcite. The X-ray diffraction shows the presence of more than 30 % of amorphous material for both clays. In clay 2 the amorphous phase is almost present in the same concentration as the smectite (ratio 100:95), whereas in clay 1 the ratio of smectite to amorphous material is 100:85.

[0110] The dyes used for making encapsulated dye composition are listed in below table:
Colour Index NameChemical classTrade Name
C.I. Acid Violet 17 Triaryl methane dye Duasyn Acid Violet 4BN-IN
C.I. Direct Violet 66 Diazo dye Duasyn Violet SP-IN
C.I. Acid Violet 54 Azo Dye Duasyn Red N-6B-IN
C.I. Acid Violet 48 Anthraquinone Dye Duasyn Violet FBL-IN
C.I. Acid Violet 126 Anthraquinone Dye Duasyn Red Violet E2R-IN


[0111] The silica used in the present invention having the properties as listed in the below table:
Silica NameSupplierProperties   
Hydrophilic/ HydrophobicParticle Size, d(50) µmDOA Absorption, ml/100gTamped Density, g/l
Sipernat® 22 Evonik Hydrophilic 120 240 245
Sipernat® D 17 Evonik Hydrophobic 10 - 150
Ibersil® D 100 P IQESII S.A. Hydrophilic 200 245 230-280


[0112] Comparative examples of encapsulated dye composition using Sipernat® 22

Comparative Example 1:



[0113] 
Ingredientsg%
SIPERNAT® 22 8.0 80
Dye premix:    
Duasyn Acid Violet 4BN-IN 1.0 10
water 1.0 10
Total: 10 100


[0114] Method: 8.0g of Sipernat® 22 (Silicon Dioxide, hydrophilic Silica) and 2g of dye premix containing 1 g of Duasyn Acid Violet 4BN-IN and 1 g of water was mixed manually to obtain the encapsulated dye composition.

[0115] The encapsulated dye composition was a violet color formulation comprising -10% Duasyn Acid Violet 4BN-IN.

Comparative Example 2:



[0116] 
Ingredientsg%
SIPERNAT® 22 9.0 90
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.5 5
water 0.5 5
Total: 10 100


[0117] Method: 9.0g of Sipernat® 22 (Silicon Dioxide, hydrophilic Silica) and 1g of dye premix containing 0.5 g of Duasyn Acid Violet 4BN-IN and 0.5 g of water was mixed manually to obtain encapsulated dye composition.

[0118] The encapsulated dye composition was a violet color formulation comprising -5% Duasyn Acid Violet 4BN-IN.

Comparative Example 3:



[0119] 
Ingredientsg%
SIPERNAT® 22 4 40
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.12 1.2
water 5.88 58.8
Total: 10 100


[0120] Method: 4.0g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 6g of dye premix containing Duasyn Acid Violet 4BN-IN dye and water was mixed manually to obtain the encapsulated dye composition.

[0121] The dye composition was a violet color formulation comprising ∼1.2 % Duasyn Acid Violet 4BN-IN.

Comparative Example 4:



[0122] 
Ingredientsg%
SIPERNAT® 22 7.5 75
Dye premix:    
Duasyn Acid Violet 4BN-IN 1.5 15
HPMC 0.36 3.6
water 0.64 6.4
Total 10 100


[0123] Method: 7.5g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 2.5g of dye premix containing Duasyn Acid Violet 4BN-IN, HPMC and water were mixed manually to obtain the encapsulated dye composition. The so obtained dye composition was a violet color formulation.

Comparative Example 5:



[0124] 
Ingredientsg%
SIPERNAT® 22 8.33 83.3
Dye premix:    
Duasyn Acid Violet 4BN-IN 1.0 10
HPMC 0.24 2.4
water 0.43 4.3
Total 10 100


[0125] Method: 8.33g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 1.67g of dye premix containing Duasyn Acid Violet 4BN-IN, HPMC and water were mixed manually to obtain the encapsulated dye composition. The so obtained dye composition was a violet color formulation.

Comparative Example 6:



[0126] 
Ingredientsg%
SIPERNAT® 22 8.76 87.6
Dye premix:    
Duasyn Acid Violet 4BN-IN 1.0 10
HPMC 0.24 2.4
Total 10 100


[0127] Method: 8.76g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 1.24g of dye premix containing Duasyn Acid Violet 4BN-IN, HPMC were mixed manually and dried at 90°C for 1 day (to make it moisture free) to obtain the encapsulated dye composition. The so obtained dye composition was a faint violet color formulation.

Comparative Example 7



[0128] 
Ingredientsg%
SIPERNAT® 22 9.38 93.8
Dye Premix :    
Duasyn Acid Violet 4BN-IN 0.5 5
HPMC 0.12 1.2
Total 10 100


[0129] Method : 9.38g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and dye premix containing Duasyn Acid Violet 4BN-IN and HPMC were mixed manually and dried at 90°C for 1 day (to make it moisture free) to obtain the encapsulated dye composition. The so obtained dye composition had faint violet color.

[0130] The following examples are dye compositions prepared according to the present invention:

Example 1


Composition 1:



[0131] 
Ingredientsg%
Sipernat® 22 4 40
Clay 1 (Laundrosil® DGA powder): 1 10
Clay 2 (EXM 0242) 1 10
Duasyn Acid Violet 4BN-IN 5% Aq. Dispersion:    
Duasyn Acid Violet 4BN-IN 0.2 2
Water 3.8 38
Total: 10 100


[0132] Method: 4g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica), 1g of Clay 1 Laundrosil® DGA powder(soda activated bentonite) and Clay 2 EXM 0242 (natural calcium-bentonite) were mixed to obtain a first mixture. The so obtained first mixture was blended with 4g of 5% aq. dispersion of Duasyn Acid Violet 4BN-IN to obtain the encapsulated dye composition. During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was violet color formulation comprising 2% dye. It was observed that the color becomes more intense after storage at 45°C within a week. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 2


Composition 2:



[0133] 
Ingredientsg%
Sipernat® 22 4 40
Duasyn Acid Violet 4BN-IN (5% Aq.):    
Duasyn Acid Violet 4BN-IN 0.2 2
Water 3.8 38
Clay 1 Laundrosil® DGA powder 1 10
Clay 2 EXM 0242 1 10
Total 10 100%


[0134] Method: 4g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica) and 4g of 5% aq. dispersion of Duasyn Acid Violet 4BN-IN were mixed to obtain a first mixture. The so obtained first mixture was blended with 1g of Clay 1 Laundrosil® DGA powder (soda activated bentonite) to obtain second mixture. Second mixture was mixed with 1g of Clay 2 EXM 0242 (natural calcium-bentonite) to obtain the encapsulated dye composition.

[0135] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a violet color formulation comprising 2% dye. It was observed that the color becomes more intense after storage at 45°C within a week. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 3


Composition 3:



[0136] 
Ingredientsg%
Sipernat® D 17 3 30
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.5 5
water 0.5 5
Ibersil® D 100 P 2 20
Clay1(Laundrosil ® DGA powder 4 40
Total 10 100


[0137] Method: 3g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 1g of dye premix containing Duasyn Acid Violet 4BN-IN and water were mixed to obtain a first mixture. The so obtained first mixture was blended with 2g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200 micron) to obtain second mixture. Second mixture was mixed with 4g of Clay 1 (soda activated bentonite, Laundrosil®DGA powder) to obtain the encapsulated dye composition.

[0138] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a violet color formulation comprising 5% dye. It was observed that the color becomes more intense after storage at 45°C within a week. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 4


Composition 4:



[0139] 
Ingredientsg%
Sipernat® D 17 2 20
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.05 0.5
water 0.05 0.5
Ibersil® D 100 P 3 30
Clay 1 (Laundrosil® DGA powder 4.9 49
Total 10 100%


[0140] Method: 2g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 0.1g of dye premix containing Duasyn Acid Violet 4BN-IN and water were mixed to obtain a first mixture. The so obtained first mixture was blended with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200 micron) to obtain second mixture. Second mixture was mixed with 4.9 g Clay 1 Laundrosil® DGA powder (soda activated bentonite) to obtain the encapsulated dye composition.

[0141] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -0.5% dye, which was found to be stable at room temperature (RT) and at 45°C on storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 5


Composition 5:



[0142] 
Ingredientsg%
Sipernat® D 17 3 30
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.6 6
Water 0.4 4
Ibersil® D 100 P 2 20
Clay 1 (Laundrosil® DGApowder 4 40
Total 10 100


[0143] Method: 3g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 1g of dye premix containing Duasyn Acid Violet 4BN-IN and water were mixed to obtain a first mixture. The so obtained first mixture was blended with 2g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain second mixture. Second mixture was mixed with 4g Clay 1 Laundrosil® DGA powder (soda activated bentonite) to obtain the encapsulated dye composition.

[0144] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -6% dye, which was found to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 6


Composition 6:



[0145] 
Ingredientsg%
Sipernat® D 17 2 20
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.06 0.6
water 0.04 0.4
Ibersil® D 100 P 3 30
Clay 1 (Laundrosil® DGA powder 4.9 49
Total 10 100%


[0146] Method: 2g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 0.1g of dye premix containing Duasyn Acid Violet 4BN-IN (Triaryl methane dye) and water were mixed to obtain a first mixture. The so obtained first mixture was blended with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d(50):∼200micron) to obtain a second mixture. Second mixture was mixed with 4.9g Clay 1 (soda activated bentonite, Laundrosil® DGA powder) to obtain the encapsulated dye composition.

[0147] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -0.6% dye, which was found to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 7


Composition 7:



[0148] 
Ingredientsg%
Sipernat® D 17 3 30
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.25 2.5
Duasyn Violet SP-IN 0.25 2.5
water 0.5 5
Ibersil® D 100 P 2 20
Clay 1 (Laundrosil® DGA powder 4 40
Total 10 100


[0149] Method: 3g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 1g of dye premix containing 1:1 ratio of Duasyn Acid Violet 4BN-IN and Duasyn Violet SP-IN along with water were mixed to obtain a first mixture. The so obtained first mixture was blended with 2g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain second mixture. Second mixture was mixed with 4g Clay 1 (Laundrosil® DGA powder (soda activated bentonite) to obtain the encapsulated dye composition.

[0150] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -5% dye, which was found to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 8


Composition 8:



[0151] 
Ingredientsg%
Sipernat® D 17 2 20
Dye premix:    
Duasyn Acid Violet 4BN-IN 0.025 0.25
Duasyn Violet SP-IN (1:1) 0.025 0.25
water 0.05 0.5
Ibersil® D 100 P 3 30
Clay 1 (Laundrosil® DGA® powder 4.9 49
Total   100


[0152] Method: 2g of Sipernat® D 17 (Silicon Dioxide, Hydrophobic Silica) and 0.1g of dye premix containing 1:1 ratio of Duasyn Acid Violet 4BN-IN and Duasyn Violet SP-IN in water were mixed to obtain a first mixture. The so obtained first mixture was blended with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain a second mixture. Second mixture was mixed with 4.9g Clay 1 Laundrosil® DGA powder (soda activated bentonite) to obtain the encapsulated dye composition.

[0153] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -0.5% dye and was found to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 9


Composition 9:



[0154] 
Ingredientsg%
Dye premix:  
Duasyn Violet 4BN-IN 0.7 7
HPMC 0.25 2.5
water 2.05 20.5
Sipernat® D17 0.5 5
Ibersil® D 100 P 3 30
Mixture of Clay 2 EXM 0242 and Clay 1 (Laundrosil® DGApowder 3.5 35
Total 10 100


[0155] Method: 3g of dye premix containing Duasyn Violet 4BN-IN, HPMC and water were blended with Sipernat® D 17 to obtain a first mixture. The so obtained first mixture was blended with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain second mixture. Second mixture was mixed with 3.5g blend of Clay 2 EXM 0242 (natural calcium-bentonite) and Clay 1 (Laundrosil® DGA powder (soda activated bentonite) to obtain the encapsulated dye composition.

[0156] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -7% dye, which was found to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 10


Composition 10:



[0157] 
Ingredientsg%
Dye premix:    
Duasyn Violet SP-IN 1 10
HPMC 0.25 2.5
Water 1.75 17.5
Sipernat® D17 0.5 5
Ibersil® D 100 P 3 30
Clay 2 EXM 0242 and Clay 1 (Laundrosil® DGA powder 3.5 35
Total 10 100%


[0158] Method: 3g of dye premix containing Duasyn Violet SP-IN, HPMC and water were blended with Sipernat D® 17 (Silicon Dioxide, Hydrophobic Silica from Evonik Industries) to obtain a first mixture. First mixture was mixed with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain a second mixture. Second mixture was mixed with 3.5g blend of Clay 2 (EXM 0242) (natural calcium-bentonite) and Clay 1 Laundrosil® DGA-powder (soda activated bentonite) to obtain the encapsulated dye composition.

[0159] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -10% dye, which was found to be stable at RT and at 45°C on storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring.

Example 11


Composition 11:



[0160] 
Ingredientsg%
Dye premix:    
Duasyn Red N-6B-IN 1 10
HPMC 0.25 2.5
water 1.75 17.5
Ibersil® D 100 P 3 30
Clay 2 EXM 0242® and Clay 1 Laundrosil® 4 40
DGApowder    
Total 10 100


[0161] Method: 3g of dye premix containing Duasyn Red N-6B-IN, HPMC and water were blended with Sipernat D® 17 (Silicon Dioxide, Hydrophobic Silica from Evonik Industries) to obtain a first mixture. The so obtained first mixture was blended with 3g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) to obtain second mixture. Second mixture was mixed with 4g blend of Clay 2 EXM 0242 (natural calcium-bentonite) and Clay 1 Laundrosil® DGA powder® (soda activated bentonite) to obtain the encapsulated dye composition.

[0162] During preparation, the mixing was done manually for encapsulation. The so obtained dye composition was a white color formulation comprising -10% dye, which was found to be stable at RT and at 45°C upon storage for 2 months. Formulation was found to release dye within few seconds in water with gentle stirring. The same formulation could be prepared using Duasyn Violet FBL-IN, Duasyn Red Violet E2R-IN or mixtures of two or three dyes mentioned in this example.

Example 12



[0163] Composition 12: The encapsulated dye composition is prepared using Fluidized Bed Process.
 Ingredientsg%
Phase A: Carrier Ibersil® D 100 P 200 40
Clay 1 Laundrosil® DGApowder 100 20
Clay 2 EXM 0242® 100 20
Phase B: Dye premix in water Duasyn Acid Violet 4BN-IN 100 20
Coating solution for Fluidized Bed Processing HPMC 4  
TiO2 (Viscofil White ARCL 30) in water 10  


[0164] Method: Dye premix containing 100g of Duasyn Acid Violet 4BN-IN dye in water was mixed with a mixture of 200g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron), 100g of Clay 1 Laundrosil® DGA-powder (soda activated bentonite) and 100g of Clay 2 EX® 0242 (natural Ca-bentonite) in Stephen mixer to obtain a mixture/dough cake. The mixture/dough cake was extruded through an extruder to obtain extrudates. The extrudates were spheronized to obtain granules. Obtained granules were further dried at 45°C in oven to remove any moisture. The granules were coated with the binder to obtain the encapsulated dye composition. The above Table shows the final composition of the encapsulated dye composition 12.

[0165] It was observed that the off white HPMC coated beads of the dye composition was stable at RT and at 45°C for 2 months. The formulation was found to release dye within few seconds in water with gentle stirring and no dye staining on cloth piece after washing.

Example 13


Composition 13:



[0166] 
Ingredientsg%
Ibersil® D 100 P 4.02 40.2
Dye Premix  
Duasyn Acid Violet 4BN-IN 1.8 18
HPMC 0.18 1.8
Clay 3 (Tonsil Supreme® 118 FF) 2 20
Clay 1 Laundrosil® DGA-powder 2 20
Total 10 100


[0167] Method: 4.02g of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron) and 3g dye premix containing Duasyn Acid Violet 4BN-IN and HPMC were mixed to obtain a first mixture. The so obtained first mixture was blended with 2g of Clay 3 Tonsil Supreme® 118 FF to obtain second mixture. Second mixture was mixed with 2g Clay 1 Laundrosil® DGA-powder (soda activated bentonite) to obtain the encapsulated dye composition. Encapsulated dye sample was further dried at 80-90°C for 1 day for complete moisture removal.

[0168] The so obtained dye composition was found to be a white color formulation comprising -18% Dye. The mixing was done manually for encapsulation. The dye composition was found to be stable at RT and at 45°C on storage for 2 months. The formulation was found to release dye within few seconds in water with gentle stirring. The dye composition was found stable in strength testing. Instead of using Duasyn Acid Violet 4BN-IN for the premix, alternatively Duasyn Violet SP-IN, Duasyn Red N-6B-IN, Duasyn Violet FBL-IN or Duasyn Red Violet E2R-IN or a mixture of two or several of the afore mentioned dye can be used for the preparation of the formulation mentioned in this example.

Example 14


Composition 14:



[0169] 
 Ingredientsg%
Phase A: Carrier Sipernat® 22 68 34
Clay 1 Laundrosil DGA® -powder 40 20
Clay 2 EXM 0242® 40 20
Phase B: Dye Premix      
Duasyn Violet SP-IN 40 20
HPMC 12 6
Total 200 100


[0170] Method: 52g of phase B, dye premix containing Duasyn Violet SP-IN and HPMC, was mixed with a mixture of 68g of Sipernat® 22 (Silicon Dioxide, Hydrophilic Silica), 40g of Clay 1 Laundrosil DGA®-powder (soda activated bentonite) and 40g of Clay 2 EXM 0242® in Stephen mixer to obtain a mixture/dough cake. The mixture/dough cake was extruded through an extruder to obtain extrudates. The extrudates were spheronized to obtain granules. Obtained granules were further dried at 45°C in oven.

[0171] The dye composition was found to be violet colored granules, which were found to be stable at RT and at 45°C storage for 2 months. The formulation was found to release dye within few seconds in water with gentle stirring. The dye composition was found to be stable in strength testing and no dye staining on cloth piece after washing. Similar formulations can be prepared with the shading dyes Duasyn Acid Violet 4BN-IN, Duasyn Red N-6B-IN, Duasyn Violet FBL-IN, Duasyn Red Violet E2R-IN or a mixture of two or several of the afore mentioned dyes.

Example 15



[0172] Composition 15: The encapsulated dye composition is prepared using Fluidized Bed Process.
 Ingredientsg%
Phase A: Carrier Ibersil® D 100 P 199.5 38
Laundrosil® DGA-powder 99.75 19
  EXM 0242 99.75 19
Phase B: Dye premix Duasyn Acid Violet 4BN-IN 99.75 19
Coating HPMC 5.25 1
Viscofil White ARCL 30 21 4
  Total = 525 100


[0173] Method: Dye premix containing Duasyn Acid Violet 4BN-IN in water was mixed with a mixture of Ibersil® D 100 P (Silicon Dioxide, Hydrophilic Silica with bigger particle size, d (50):∼ 200micron), Laundrosil DGA-powder and EXM 0242 (bentonite/Clay) in Stephen mixer to obtain a mixture/dough cake. The mixture/dough cake was extruded through an extruder to obtain extrudates. The extrudates were spheronized to obtain granules. Obtained granules were further dried at 45°C in oven to remove any moisture. The granules were coated with HPMC and Viscofil White ARCL 30 to obtain the encapsulated dye composition. The final composition of the encapsulated dye is given in the above Table.

[0174] The so obtained dye composition was off white color HPMC coated beads, which were found to be stable at RT and at 50°C on storage for 2 months. The formulation was found to release dye within few seconds in water with gentle stirring.

[0175] Comparable Formulations can be prepared using Duasyn Violet SP-IN or Duasyn Red N-6B-IN, Duasyn Violet FBL-IN or Duasyn Red Violet E2R-IN or a mixture of two or several of the fore mentioned dyes.

Example 16



[0176] Various formulations of the compositions of present invention are tested for their effects which are discussed as below.

[0177] Methods for testing the encapsulated dye composition of the present invention

A] Open dish stability test



[0178] Method: Open dish stability test was carried out to test the bleeding character of the encapsulated dye composition. The encapsulated dye composition was mixed with the white detergent powder and the resulting powder was kept in a petri dish and was left in the open environment for up to 2 months at room temperature and elevated temperature to check bleeding.

[0179] Result: It was observed that even after four weeks, the white powder did not change its color and there was no migration of the dye from the encapsulated dye composition. Thus, the encapsulated dye composition was found to be stable.

B] Strength of encapsulated samples testing



[0180] Method: The encapsulated dye compositions of the present invention prepared according to the above examples were used for the strength testing. The encapsulated sample was added to the powder detergent or components such as sodium sulfate. The sample was exposed to shear mimicking conditions of mixing dye with powder detergent. The sample was further observed after strength testing for migration of dye in powder detergent/sodium sulfate.

[0181] Result: It was observed that dye material was not migrating in powder detergent after performing the strength testing and white powder was not changing its original color.

C] Dye Staining testing



[0182] Method: The encapsulated dye composition of the present invention prepared according to the above examples were used for the dye staining test by conventional methods on the required fabrics such as woven polyester fabric, woven polycotton fabric, woven cotton CN-II fabric, elastane/nylon fabric.

[0183] Result: It was observed that no stains were left after the washing cycle on the fabric material. Thus, the encapsulated dye composition was found to be washed out easily from the fabric.


Claims

1. An encapsulated dye composition comprising:

a) carrier consisting of a mixture of silica and clay; and

b) at least one dye encapsulated in the carrier.


 
2. The composition as claimed in claim 1 further comprises a binder.
 
3. The composition as claimed in claim 1, wherein said dye is selected from anionic azine dye or cationic phenazine dye, triaryl-methane dye, triphenyl-methane dye, anthraquinone dye, azo dye, disazo dye, phthalocyanine dye, quinophthalone dye, methine dye, hemicyanine dye, azo/azomethine complex dye, triphendioxazine dye or any mixtures thereof.
 
4. The composition as claimed in claim 3, wherein the dye is selected from the group consisting of Duasyn Acid Violet 4BN-IN (C.I. Acid Violet 17), Duasyn Violet SP-IN (C.I. Direct Violet 66), Duasyn Red N-6B-IN (C.I. Acid Violet 54), Duasyn Violet FBL-IN (C.I. Acid Violet 48), Duasyn Red Violet E2R-IN (C.I. Acid Violet 126) or mixtures of one or several of the afore mentioned dyes.
 
5. The composition as claimed in claim 1, wherein said dye is used in the amount in the range of 1% to 30%, preferably 5% to 20% based on the total weight of the encapsulated dye composition.
 
6. The composition as claimed in claim 1, wherein the carrier has a ratio of silica to clay of from 1:4 to 4:1.
 
7. The composition as claimed in claim 1, wherein said clay is selected from the group consisting of natural clays comprising bentonite, montmorillonite, beidellite, saponite, hectorite, stevensite, kerolite-saponite, kerolite, talc, pyrophyllite, attapulgite, sepiolite; a mixture of natural silica with a bentonite;any modified clays; and any mixtures thereof.
 
8. The composition as claimed in claim 7, wherein the clay contains a natural or sodium activated bentonite or a mixture containing both.
 
9. The composition as claimed in claim 7, wherein said clay contains a natural or sodium activated bentonite with a cation exchange capacity in the range of 10 meq/100 g to 140 meq/100g.
 
10. The composition as claimed in claim 7, wherein the clay contains a natural or sodium activated bentonite with a cation exchange capacity in the range of 20 and 130 meq/100g, preferably in the range of 30 and 120 meq/100 g.
 
11. The composition as claimed in claim 1, wherein said clay has:

a. a surface area of more than 120 m2/g;

b. a total pore volume of more than 0.35 ml/g;

c. a silicon content, calculated as SiO2, of at least 60 wt.%.


 
12. The composition as claimed in claim 11, wherein said clay has more than 10 % of amorphous material as determined by quantitative X-ray diffraction analysis of the mineral phases of the clay material.
 
13. The composition as claimed in claim 1, wherein the clay is used in the amount of 30% to 75% based on the total weight of composition.
 
14. The composition as claimed in claim 1, wherein the silica is selected from the group consisting of silica gel, a pyrogenic silica or a precipitated silica or mixtures thereof.
 
15. The composition as claimed in claim 14, wherein the silica is a precipitated silica.
 
16. The composition as claimed in claim 15, wherein the precipitated silica is a hydrophilic precipitated silica or a hydrophobic precipitated silica or a mixture of both.
 
17. The composition as claimed in claim 16 wherein the hydrophilic silica has a liquid carrying capacity determined as DOA absorption number of at least 120 ml/100g, preferably at least 140 ml/100g, mostly preferred at least 160 ml/100g precipitated silica.
 
18. The composition as claimed in claim 16 wherein the hydrophilic silica has a particle size d50 determined by laser diffraction of at least 50 µm, preferably at least 70 µm, mostly preferred at least 90 µm.
 
19. The composition as claimed in claim 16 wherein the hydrophobic silica has a particle size d50 determined by laser diffraction of at least 5 µm, preferably at least 7 µm, mostly preferred at least 9 µm.
 
20. The dye composition as claimed in claim 1, wherein said silica is used in the amount of 30% to 75% based on the total weight of the composition.
 
21. The composition as claimed in claim 2, wherein said binder is a surfactant or a polymer.
 
22. The composition as claimed in claim 21, wherein said polymer is hydroxyl propyl methyl cellulose.
 
23. The composition as claimed in claim 2, wherein the binder is used in the amount of 1 to 5% based on the total weight of the composition.
 
24. A method for preparing an encapsulated dye composition comprising:

a) mixing a dye with a carrier to obtain a mixture;

b) adding water to the mixture to obtain a semisolid mass;

c) extruding the semisolid mass through an extruder to obtain extrudates;

d) spheronizing the extrudates to obtain granules; and

e) optionally coating the granules with a binder and TiO2 dispersion to obtain the encapsulated dye composition.


 
25. A method for preparing an encapsulated dye composition comprising:

a) mixing a dye with a carrier to obtain a mixture;

b) adding water, optionally with binder to the mixture to obtain a semisolid mass;

c) extruding the semisolid mass through an extruder to obtain extrudates;

d) spheronizing the extrudates to obtain granules


 
26. A method for preparing an encapsulated dye composition comprising mixing at least one dye, silica, clay and binder manually to obtain dye composition encapsulated in the carrier comprising the steps of

a) mixing a dye with a binder to obtain a first mixture;

b) blending the mixture with a portion of hydrophobic silica to obtain a second mixture;

c) mixing the second mixture with a portion of hydrophilic silica to obtain a third mixture; and

d) blending the third mixture with a portion of clay to obtain the encapsulated dye composition.


 
27. The process as claimed in claim 25 or 26 wherein encapsulated dye composition is obtained in the powder form or in granular form.
 
28. Laundry detergent composition comprising encapsulated dye composition comprising carrier consisting of a mixture of silica and clay; and at least one dye encapsulated in the carrier.
 
29. A detergent composition comprising encapsulated dye composition, wherein said dye composition comprising:

a carrier consisting of 30% to 75% by weight of silica and 30% to 75% by weight of clay;

1 to 5% by weight of binder; and

1 to 20% by weight of dye.


 





Search report


















Search report




Cited references

REFERENCES CITED IN THE DESCRIPTION



This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

Patent documents cited in the description




Non-patent literature cited in the description