FIELD OF THE INVENTION
[0001] A water-soluble single-use polyhedron package comprising liquid detergent with at
least two layers in the water-soluble body portion and a process of its preparation.
BACKGROUND OF THE INVENTION
[0002] Detergent compositions are provided in many forms, of which granular and liquid compositions
are the most prevalent. More recently, unit dose forms of detergent have been proposed
in the form of compressed tablets of detergent powder or water-soluble packages, which
are consumed during a single cleaning application. The unit dose forms are preferred
by some consumers, in that the dose is premeasured and, consequently, the unit dose
form is faster, easier and less messy to use. Water-soluble packages filled with liquid
detergent composition are desired especially by consumers who are used to liquid detergents.
[0003] Water-soluble unit dose packages containing liquids are known. See, for instance,
Kennedy (US Patent 4,973,416), Dickler et al. (US Patent 6,037,319), Haq (US Patent
4,416,791) and Richardson (US Patent 4,115,292). The packages may contain various
amounts, including relatively high, amounts of water. See for instance WO 94/14941,
EP 518 689, WO 97/27743, and JP 06/340,899.
[0004] Packages of various shapes are disclosed by Huff, U.S. Patent No. 6,040,286, Buchanan,
U.S. Patent No. 5,273,362, Anderson, U.S. Patent No. 4,810,844, Mahler et al., U.S.
Patent No. 4,223,029, Wierenga et al., U.S. Patent No. 5,002,681, Smith et al., U.S.
Patent No. DES 392,559, Buchanan et al., U.S. Patent No. 5,135,464, and Buchanan et
al., U.S. Patent No. 6,120,183. Giessen, U.S. Patent 2,444,987; Schneider et al. US.
Patent 3,367,489; Shaw et al., U.S. Patent 3,618,758; Guerry et al., U.S. Patent 4,176,079;
Davies et al., U.S. Patent 4,410,441; Ginn, U.S. Patent 4,588,080; Ginn, U.S. Patent
4,680,916; Leigh et al., U.S. Patent 4,706,802; Gouge et al., U.S. Patent 5,224,601;
Saam, U.S. Patent 5,927,498.
[0005] It is sometimes desirable to separate various ingredients of the detergent composition.
See for instance WO 01/60966 disclosing a multi-compartment water-soluble pouch. It
is also desirable to increase the visual appeal of the package and, also, to provide
a unique appearance to be associated by consumers with a particular product. In addition,
it is desirable to provide a visual signal to a consumer of the presence of special
(e.g., benefit) ingredient in the composition.
[0006] EP 116422, EP 175485, GB 1247189, WO 99/47635, and Ginn (US Patent 4,348,292) disclose
dual layer liquid cleaning compositions in a bottle or a water insoluble package.
The layers are achieved by employing an electrolyte, which when added to an aqueous
surfactant solution, forces the separation of the surfactant from the aqueous phase.
The phenomenon of separating an organic component from an aqueous layer, by the addition
of a salt (electrolyte) is known as "salting out." The salt increases the ionic character
of water and drives the organic, less polar, component away.
[0007] Another known technique for separating ingredients in a common container includes
encapsulation. Encapsulation technology is well known for different applications.
Generally, encapsulation includes a medium that surrounds at least one component and
thereby provides a barrier between the "encapsulated" component and other components.
The barrier is typically temporary and is designed to break down and release the encapsulated
material at a desired time, such as at a particular temperature, upon reaction or
dissolution with chemicals, or due to mechanical stress. Methods of encapsulation
include coacervation, liposome formation, granulation, coating, emulsification, atomization
and spray-cooling.
[0008] See, for instance, the disclosures of enzyme encapsulates and encapsulation processes:
Falholt et al. (U.S. Patent 4,906,396, UK 2,186 884, and EP 0 273 775), Tsaur et al.
(U.S. Patents 5,434,069 and 5,441,660), Ratuiste et al. (U.S. Patent 5,589,370). See
also Mitchnik et al. (U.S. Patent 5,733,531) and Leong (U.S. Patent 5,296,166).
[0009] It is desirable to provide a layered liquid detergent composition in a water-soluble
single use package, which provides additional protection to sensitive ingredients.
SUMMARY OF THE INVENTION
[0010] The present invention includes a layered liquid detergent composition in a water-soluble
single use package, wherein the package is in the shape of a polyhedron, preferably
a tetrahedron. The composition comprises at least two layers, hydrophilic and hydrophobic,
with the hydrophobic layer preferably on top. The hydrophobic layer preferably comprises
a sensitive benefit ingredient (e.g., enzyme), which is contained predominantly in
the hydrophobic layer. By virtue of the shape of the package, the interface between
the top layer and the next lower layer is minimized, which in turn leads to a reduced
interaction between the two layers, resulting in the increased stability of the ingredient
in the top layer.
[0011] The following detailed description and the examples illustrate some of the effects
of the inventive compositions. The invention and the claims, however, are not limited
to the following description and examples.
DETAILED DESCRIPTION OF THE INVENTION
[0012] All amounts are by weight of the liquid detergent composition, unless otherwise specified.
[0013] It should be noted that in specifying any range of concentration, any particular
upper concentration can be associated with any particular lower concentration.
[0014] For the avoidance of doubt the word "comprising" is intended to mean "including"
but not necessarily "consisting of" or "composed of." In other words, the listed steps
or options need not be exhaustive.
[0015] "Water-soluble body" as used herein means soluble in cold water, i.e. soluble at
5°C and above.
[0016] "Liquid" as used herein means that a continuous phase or predominant part of the
composition is liquid and that a composition is flowable at 20°C. Solids (e.g., suspended
or other) may be included.
[0017] "Seal" or "sealing" as used herein includes both heat sealing and water sealing.
[0018] "Transparent" as used herein includes both transparent and translucent and means
that an ingredient, or a mixture, or a phase, or a composition, or a package according
to the invention preferably has a transmittance of more than 25%, more preferably
more than 30%, most preferably more than 40%, optimally more than 50% in the visible
part of the spectrum (approx. 410-800 nm). Alternatively, absorbency may be measured
as less than 0.6 (approximately equivalent to 25% transmitting) or by having transmittance
greater than 25% wherein % transmittance equals: 1/10
absorbancy x 100%. For purposes of the invention, as long as one wavelength in the visible light
range has greater than 25% transmittance, it is considered to be transparent/translucent.
[0019] The term "composition" or "liquid detergent composition" as used herein means the
final detergent composition (i.e., the detergent composition itself, but not the water-soluble
body), including at least two layers.
WATER-SOLUBLE BODY PORTION
[0020] The package is preferably made of a clear, sealable, cold water soluble film such
as polyvinyl alcohol. Thickness could range from 25 to 100 µm, more preferably from
35 to 80 µm, most preferably from 45 to 75 µm. Other materials from which the package
can be made include but are not limited to methyl hydroxy propyl cellulose and polyethylene
oxide. Polyvinyl alcohol is preferred due to its ready availability and low cost.
One supplier of polyvinyl alcohol film is Monosol LLC. European suppliers of suitable
films include but are not limited to Monosol supplied by Monosol LLC. or PT supplied
by Aicello or K-series supplied by Kurary or Hydrafilm supplied by Rainier Specialty
Polymers Ltd, or QSA series by Polymer Films, Inc.
[0021] Preferably the water-soluble film of the base wall is the same material as that used
to make the body wall. Both thermoforming and cold forming (e.g., with water) are
possible.
[0022] The water-soluble package of the invention is in the shape of the polyhedron having
four or more walls wherein each wall is inclined at an angle relative to each other
wall.
[0023] Preferably the inclination of each wall is between 30 and 90 degrees, more preferably
between 30 and 60 degrees.
[0024] In a preferred embodiment, the package is in the form of a tetrahedron (four-walled
polyhedron). The tetrahedron may be regular or irregular i.e. the walls may take the
shape of regular or irregular polygons. The tetrahedron shape is advantageous in that
it can be a fairly simple structure to manufacture (as compared with other polyhedrons
with more walls) and at the same time the inclination of each wall relative to each
other walls is optimised.
The package may be formed by any suitable method, but preferably is being formed from
a flexible film disposed in folded configuration and sealed with one or more longitudinal
seals; and first and second end seals located at opposed ends of the package, wherein
the first end seal is substantially orthogonal to the or each longitudinal seal and
inclined at an angle to the second end seal.
[0025] With this arrangement, the package may be formed into a polyhedron by adapting existing
vertical form fill and seal machinery, thereby reducing the costs of producing packages
according to the invention.
[0026] Preferably, the relative inclination of first and second end seals is between 30
and 90 degrees. In a preferred embodiment, the first and second end seals are orientated
orthogonal relative to each other. This provides a tetrahedron shaped package.
[0027] The transition between adjacent walls may be slightly curved (e.g. due to the force
exerted by the contents of the package, and the flexibility of the package material)
while at the same time, distinct walls can still be seen and are still distinguishable
from one another.
[0028] The walls may be substantially flat, however, this is not essential, indeed the or
each wall may have a slight curvature (e.g. due to the force exerted by the contents
of the package, and the flexibility of the package material) so long as the overall
shape is still apparent and the general plane of each wall is inclined to the general
plane of each of the other walls.
[0029] The edges of the polyhedron may be formed with increased sharpness by, for example,
arrangement of one or more seals during formation, so that one or more seals are orientated
along respective one or more edge portions of the polyhedron to give more distinct
edges.
LAUNDRY COMPOSITION
Layers
[0030] The laundry compositions within the scope of the invention are liquid compositions
comprising at least two layers, wherein at least one layer is hydrophilic and at least
one layer is hydrophobic. The hydrophobic layer is typically and preferably the top
layer.
[0031] The hydrophilic layer employs water, typically in an amount of from 0 to 60%, preferably
from 5 to 50%, most preferably from 10 to 40%, by weight of the hydrophilic layer.
[0032] The hydrophobic layer employs a hydrophobic liquid, typically in an amount of from
30 to 100%, preferably from 40 to 80%, most preferably from 50 to 70%, by weight of
the hydrophobic layer. The hydrophobic fluid is generally selected from the group
consisting of paraffin, wax, oil, petrolatum, a hydrophobic polymer and mixtures thereof.
Natural or synthetic hydrocarbon oil or mixtures thereof may be employed. Generally,
the hydrocarbon oil may be a paraffinic oil, a naphthenic oil, natural mineral oil
or the like. Examples include but are not limited to mineral oil, castor oil, vegetable
oil, corn oil, peanut oil, jojoba oil, 2-ethylhexyl oxystearate (and other alkyl oxystearates),
acetylated lanolin alcohol, alkyl palmitates such as isopropyl palmitate, 2-ethylhexyl
palmitate, glycerol triacetates, disopropyl adipate, dioctyl adipate (and other alkyl
adipates), isopropyl myristate, C12 to C15 alcohol benzoates, and the like. Most preferably,
the oil is mineral oil, because it is both economic and most easily processable.
[0033] The hydrophobic fluid may be employed in combination with a hydrophobic benefit agent
and/or colorant (e.g. oil-soluble colorant), or it may forms a continuous phase which
surrounds a discontinuous phase. The discontinuous phase may itself be a benefit agent
and/or a colorant or it may contain an additional benefit agent and/or colorant.
[0034] Preferably, at least one layer is transparent/translucent. Preferably, at least one
layer is colored. Preferred compositions comprise two layers, with the top layer containing
majority, preferably all, of the sensitive benefit ingredient, and the bottom layer
containing the majority, preferably all, of the surfactant.
[0035] When shaken, the layers within the composition may coalesce. Yet, they separate into
visible layers, with each layer regaining its clarity (if transparent), upon standing
for at most 24 hours at 20°C.
[0036] The volume ratio of the two layers in the final composition is generally in the range
of from 1:99 to 99:1. In the preferred compositions, the bottom layer is aqueous and
is predominant, i.e. the volume ratio of the bottom layer to top layer is at least
60:40, more preferably at least 70:30, most preferably at least 80:20, in order to
provide the most pleasing appearance, optimum cleaning benefits and optimum protection
for the hydrophobic layer and ingredients contained therein. The resulting layers
have the volume ratios in the same ranges as described above (but the layer ratio
may not be the same as the starting component ratio).
[0037] It should be noted that in the final composition, the compositions of the resultant
layers do not necessarily correspond with the compositions of the respective layers
prior to their being combined into a single composition.
[0038] This is because of reaction between ingredients, in particular the acidic ingredients
and the basic ingredients (e.g., sodium hydroxide) and also, because of possible migration
of material between the two layers, or emulsification of some of the layers within
each other.
[0039] Some of the preferred embodiments of laundry products are outlined below:
No. |
Hydrophilic (bottom) Layer Ingredients |
Range % by weight of the phase |
Hydrophobic (top) layer Ingredients |
Range % by weight of the phase |
Volume ratio of bottom to top layer |
1 |
Water |
0-60 |
Petrolatum |
45-80 |
From 99:1 to 60:40 |
|
Propylene |
0-25 |
Sodium |
5-20 |
|
|
Glycol |
0-15 |
perborate |
5-20 |
|
|
Xylene |
0-95 |
Sodium |
|
|
|
Sulfonate |
0-75 |
4-nonanoyloxy |
|
|
|
Alcohol |
|
Benzene |
|
|
|
ethoxylate |
0-80 |
Sulfonate |
|
|
|
Sodium |
|
|
|
|
|
Alkylbenzene |
0-10 |
|
|
|
|
sulfonate |
|
|
|
|
|
Sodium Alcohol |
|
|
|
|
|
ethoxylate |
|
|
|
|
|
sulfate |
|
|
|
|
|
Miscellaneous |
|
|
|
|
2 |
Water |
0-60 |
Mineral oil |
40-80 |
From 99:1 to 60:40 |
|
Monoethanolami ne |
0-30 0-25 |
Kraton G1650M Lipase |
0.5-10 0.5-5 |
|
|
Propylene |
1-95 |
|
|
|
|
glycol |
1-80 |
|
|
|
|
Alcohol |
|
|
|
|
|
ethoxylate |
0-5 |
|
|
|
|
Monoethanolami ne |
0-10 |
|
|
|
|
alkylbenzene |
|
|
|
|
|
sulfonate |
|
|
|
|
|
Protease |
|
|
|
|
|
Miscellaneous |
|
|
|
|
3 |
Water |
0-65 |
Silicone oil |
40-80 |
From 99:1 to 60:40 |
|
Ammonium |
1-20 |
Paraffin wax |
5-30 |
|
|
Lauryl Sulfate |
|
Cationic |
1-10 |
|
|
Cocamide |
1-20 |
surfactant |
|
|
|
monoethanol amine |
0.1-10 |
|
|
|
|
Ammonium |
1-10 |
|
|
|
|
chloride |
|
|
|
|
|
Miscellaneous |
|
|
|
|
PREFERRED LAUNDRY COMPOSITION INGREDIENTS
[0041] The compositions of the invention preferably contain one or more surface active agents
(surfactants) selected from the group consisting of anionic, nonionic, cationic, ampholytic
and zwitterionic surfactants or mixtures thereof. The preferred surfactant detergents
for use in the present invention are mixtures of anionic and nonionic surfactants
although it is to be understood that any surfactant may be used alone or in combination
with any other surfactant or surfactants. The surfactant should comprise at least
5%, e.g., 5% to 80%, preferably at least 10% to 80%, more preferably 15% to 40%; even
more preferably 15% to 35% of the composition. Preferably, the predominant part or
all of the surfactant, e.g. at least 80% of all the surfactant in the composition,
more preferably at least 90%, is contained in the hydrophilic layer.
Nonionic Surfactant
[0042] Nonionic synthetic organic detergents which can be used with the invention, alone
or in combination with other surfactants, are described below. Nonionic surfactants
are typically included.
[0043] Preferred nonionic surfactants are nonionic surfactants whch are pourable liquids,
gels or pastes at 25°C. Nonionic detergent surfactants normally have molecular weights
of from about 300 to about 11,000. Mixtures of different nonionic detergent surfactants
may also be used, provided the mixture is a liquid gel or paste at 25°C. Optionally,
the composition may comprise one or more nonionic surfactants which are solid at 25°C.
These dissolved and/or dispersed in either or both liquid layers.
[0044] As is well known, the nonionic detergents are characterized by the presence of an
organic hydrophobic group and an organic hydrophilic group and are typically produced
by the condensation of an organic aliphatic or alkyl aromatic hydrophobic compound
with ethylene oxide (hydrophilic in nature). Typical suitable nonionic surfactants
are those disclosed in U.S. Pat. Nos. 4,316,812 and 3,630,929 and applicants' published
European specification EP-A-225,654.
[0045] Usually, the nonionic detergents are polyalkoxylated lipophiles wherein the desired
hydrophile-lipophile balance is obtained from addition of a hydrophilic polyalkoxy
group to a lipophilic moiety. A preferred class of nonionic detergent is the alkoxylated
alkanols wherein the alkanol is of 9 to 18 carbon atoms and wherein the number of
moles of alkylene oxide (of 2 or 3 carbon atoms) is from 3 to 12. Of such materials
it is preferred to employ those wherein the alkanol is a fatty alcohol of 9 to 11
or 12 to 15 carbon atoms and which contain from 5 to 8 or 5 to 9 alkoxy groups per
mole.
[0046] Exemplary of such compounds are those wherein the alkanol is of 12 to 15 carbon atoms
and which contain 7 ethylene oxide groups per mole, e.g. Neodol® 25-7 and Neodol®
23®-6.5, which products are made by Shell Chemical Company, Inc. The former is a condensation
product of a mixture of higher fatty alcohols averaging about 12 to 15 carbon atoms,
with 7 moles of ethylene oxide and the latter is a corresponding mixture wherein the
carbon atoms content of the higher fatty alcohol is 12 to 13 and the number of ethylene
oxide groups present averages 6.5. The higher alcohols are primary alkanols.
[0047] Other useful nonionics are represented by the commercially well- known class of nonionics
sold under the trademark Plurafac®. The Plurafacs® are the reaction products of a
higher linear alcohol and a mixture of ethylene and propylene oxides, containing a
mixed chain of ethylene oxide and propylene oxide, terminated by a hydroxyl group.
Examples include C
13 -C
15 fatty alcohol condensed with 6 moles ethylene oxide and 3 moles propylene oxide,
C
13 -C
15 fatty alcohol condensed with 7 moles propylene oxide and 4 moles ethylene oxide,
C
13 -C
15 fatty alcohol condensed with 5 moles propylene oxide and 10 moles ethylene oxide,
or mixtures of any of the above.
[0048] Another group of liquid nonionics are commercially available from Shell Chemical
Company, Inc. under the Dobanol® trademark: Dobanol® 91-5 is an ethoxylated C
9 -C
11 fatty alcohol with an average of 5 moles ethylene oxide and Dobanol® 23-7 is an ethoxylated
C
12-C
13 fatty alcohol with an average of 7 moles ethylene oxide per mole of fatty alcohol.
[0049] In the compositions of this invention, preferred nonionic surfactants include the
C
12 -C
15 primary fatty alcohols with relatively narrow contents of ethylene oxide in the range
of from 7 to 9 moles, and the C
9 to C
11 fatty alcohols ethoxylated with 5-6 moles ethylene oxide.
[0050] Another class of nonionic surfactants which can be used in accordance with this invention
are glycoside surfactants. Glycoside surfactants suitable for use in accordance with
the present invention include those of the formula:
RO--R'Oy-- (Z)
x
wherein R is a monovalent organic radical containing from about 6 to about 30 (preferably
from about 8 to about 18) carbon atoms; R' is a divalent hydrocarbon radical containing
from about 2 to 4 carbons atoms; 0 is an oxygen atom; y is a number which can have
an average value of from 0 to about 12 but which is most preferably zero; Z is a moiety
derived from a reducing saccharide containing 5 or 6 carbon atoms; and x is a number
having an average value of from 1 to 10 (preferably from 1.5 to 10).
[0051] A particularly preferred group of glycoside surfactants for use in the practice of
this invention includes those of the formula above in which R is a monovalent organic
radical (linear or branched) containing from about 6 to about 1 8(especially from
about 8 to about 18) carbon atoms; y is zero; z is glucose or a moiety derived therefrom;
x is a number having an average value of from 1 to about 4 (preferably from about
1 to 4).
[0052] Nonionic surfactants particularly useful for this application include, but are not
limited to: alcohol ethoxylates (e.g. Neodol® 25-9 from Shell Chemical Co.), alkyl
phenol ethoxylates (e.g. Tergitol® NP-9 from Union Carbide Corp.), alkylpolyglucosides
(e.g. Glucapon® 600CS from Henkel Corp.), polyoxyethylenated polyoxypropylene glycols
(e.g. Pluronic® L-65 from BASF Corp.), sorbitol esters (e.g. Emsorb® 2515 from Henkel
Corp.), polyoxyethylenated sorbitol esters (e.g. Emsorb® 6900 from Henkel Corp.),
alkanolamides (e.g. Alkamide® DC212/SE from Rhone-Poulenc Co.), and N-alkypyrrolidones
(e.g. Surfadone® LP-100 from ISP Technologies Inc.).
[0053] Mixtures of two or more of the nonionic surfactants can be used.
Anionic Surfactant
[0054] Anionic surface active agents which may be used in the present invention are those
surface active compounds which contain a long chain hydrocarbon hydrophobic group
in their molecular structure and a hydrophilic group, i.e.; water solubilizing group
such as sulfonate, sulfate or carboxylate group. The anionic surface active agents
include the alkali metal (e.g. sodium and potassium) water soluble higher alkyl benzene
sulfonates, alkyl sulfonates, alkyl sulfates and the alkyl polyether sulfates. They
may also include fatty acid or fatty acid soaps. The preferred anionic surface active
agents are the alkali metal, ammonium or alkanolamide salts of higher alkyl benzene
sulfonates and alkali metal, ammonium or alkanolamide salts of higher alkyl sulfonates.
[0055] Preferred higher alkyl sulfonates are those in which the alkyl groups contain 8 to
26 carbon atoms, preferably 12 to 22 carbon atoms and more preferably 14 to 18 carbon
atoms. The alkyl group in the alkyl benzene sulfonate preferably contains 8 to 16
carbon atoms and more preferably 10 to 15 carbon atoms. A particularly preferred alkyl
benzene sulfonate is the sodium or potassium dodecyl benzene sulfonate, e.g. sodium
linear dodecyl benzene sulfonate.
[0056] The primary and secondary alkyl sulfonates can be made by reacting long chain alpha-olefins
with sulfites or bisulfites, e.g. sodium bisulfite. The alkyl sulfonates can also
be made by reacting long chain normal paraffin hydrocarbons with sulfur dioxide and
oxygen as described in U.S. Pat. Nos. 2,503,280, 2,507,088, 3,372, 188 and 3,260,741
to obtain normal or secondary higher alkyl sulfonates suitable for use as surfactant
detergents.
[0057] The alkyl substituent is preferably linear, i.e. normal alkyl, however, branched
chain alkyl sulfonates can be employed, although they are not as good with respect
to biodegradability. The alkane, i.e. alkyl, substituent may be terminally sulfonated
or may be joined, for example, to the carbon atom of the chain, i.e. may be a secondary
sulfonate. It is understood in the art that the substituent may be joined to any carbon
on the alkyl chain. The higher alkyl sulfonates can be used as the alkali metal salts,
such as sodium and potassium. The preferred salts are the sodium salts. The preferred
alkyl sulfonates are the C
10 to C
18 primary normal alkyl sodium and potassium sulfonates, with the C
10 to C
15 primary normal alkyl sulfonate salt being more preferred.
[0058] Mixtures of higher alkyl benzene sulfonates and higher alkyl sulfonates can be used
as well as mixtures of higher alkyl benzene sulfonates and higher alkyl polyether
sulfates.
[0059] Also normal alkyl and branched chain alkyl sulfates (e.g., primary alkyl sulfates)
may be used as the anionic component).
[0060] The higher alkyl polyether sulfates used in accordance with the present invention
can be normal or branched chain alkyl and contain lower alkoxy groups which can contain
two or three carbon atoms. The normal higher alkyl polyether sulfates are preferred
in that they have a higher degree of biodegradability than the branched chain alkyl
and the lower poly alkoxy groups are preferably ethoxy groups.
[0061] The preferred higher alkyl poly ethoxy sulfates used in accordance with the present
invention are represented by the formula:
R'--O(CH
2 CH
2 O)p --SO
3 M,
where R' is C
8 to C
20 alkyl, preferably C
10 to C
18 and more preferably C
12 to C
15; p is 2 to 8, preferably 2 to 6, and more preferably 2 to 4;and M is an alkali metal,
such as sodium and potassium, or an ammonium cation. The sodium and potassium salts
are preferred.
[0062] A preferred higher alkyl poly ethoxylated sulfate is the sodium salt of a triethoxy
C
12 to C
15 alcohol sulfate having the formula:
C
12-15 --O--(CH
2 CH
2 O)
3 --SO
3 Na
[0063] Examples of suitable alkyl ethoxy sulfates that can be used in accordance with the
present invention are C
12-15 normal or primary alkyl triethoxy sulfate, sodium salt; n-decyl diethoxy sulfate,
sodium salt; C
12 primary alkyl diethoxy sulfate, ammonium salt; C
12 primary alkyl triethoxy sulfate, sodium salt: C
15 primary alkyl tetraethoxy sulfate, sodium salt, mixed C
14-15 normal primary alkyl mixed tri- and tetraethoxy sulfate, sodium salt; stearyl pentaethoxy
sulfate, sodium salt; and mixed C
10-18 normal primary alkyl triethoxy sulfate, potassium salt.
[0064] The normal alkyl ethoxy sulfates are readily biodegradable and are preferred. The
alkyl poly-lower alkoxy sulfates can be used in mixtures with each other and/or in
mixtures with the above discussed higher alkyl benzene, alkyl sulfonates, or alkyl
sulfates.
[0065] The alkali metal higher alkyl poly ethoxy sulfate can be used with the alkylbenzene
sulfonate and/or with an alkyl sulfonate or sulfonate, in an amount of 0 to 70%, preferably
10 to 50% and more preferably 10 to 20% by weight of entire composition.
[0066] Anionic surfactants particularly useful for this application include, but are not
limited to: linear alkyl benzene sulfonates (e.g. Vista® C-500 from Vista Chemical
Co.), alkyl sulfates (e.g. Polystep® B-5 from Stepan Co.), polyoxyethylenated alkyl
sulfates (e.g. Standapol® ES-3 from Stepan Co.), alpha olefin sulfonates (e.g. Witconate®
AOS from Witco Corp.), alpha sulfo methyl esters (e.g. Alpha-Step® MC-48 from Stepan
Co.), alkyl ether sulfates and isethionates (e.g. Jordapon® Cl from PPG Industries
Inc.).
[0067] Anionic surfactants may be added pre-neutralized or, preferably, may be formed in
situ, by neutralizing a precursor acid (fatty acid in the case of soaps). Further,
the anionic precursor or fatty acid should be over-neutralised (i.e. there should
be an excess of the alkaline material used to form the counter-ion). Inorganic salt,
preferably, sodium or potassium salt of the anionic precursor acid is preferred to
improve detergency, but organic salt results in improved transparency.
Cationic Surfactants
[0068] Many cationic surfactants are known in the art, and almost any cationic surfactant
having at least one long chain alkyl group of about 10 to 24 carbon atoms is suitable
in the present invention. Such compounds are described in "Cationic Surfactants",
Jungermann, 1970, incorporated by reference.
[0069] Specific cationic surfactants which can be used as surfactants in the subject invention
are described in detail in U.S. Pat. No. 4,497,718, hereby incorporated by reference.
[0070] As with the nonionic and anionic surfactants, the compositions of the invention may
use cationic surfactants alone or in combination with any of the other surfactants
known in the art. Of course, the compositions may contain no cationic surfactants
at all.
Amphoteric Surfactants
[0071] Ampholytic synthetic detergents can be broadly described as derivatives of aliphatic
or aliphatic derivatives of heterocyclic secondary and tertiary amines in which the
aliphatic radical may be a straight chain or a branched and wherein one of the aliphatic
substituents contains from 8 to 18 carbon atoms and at least one contains an anionic
water-solubilizing group, e.g. carboxylate, sulfonate, sulfate. Examples of compounds
falling within this definition are sodium 3(dodecylamino)propionate, sodium 3-(dodecylamino)propane-1-sulfonate,
sodium 2-(dodecylamino)ethyl sulfate, sodium 2-(dimethylamino)octadecanoate, disodium
3-(N-carboxymethyldodecylamino)propane 1-sulfonate, disodium octadecyl- imminodiacetate,
sodium 1-carboxymethyl-2-undecylimidazole, and sodium N, N-bis(2-hydroxyethyl)-2-sulfato-3-dodecoxypropylamine.
Sodium 3-(dodecylamino)propane-1-sulfonate is preferred.
[0072] Zwitterionic surfactants can be broadly described as derivatives of secondary and
tertiary amines, derivatives of heterocyclic secondary and tertiary amines, or derivatives
of quaternary ammonium, quaternary phosphonium or tertiary sulfonium compounds. The
cationic atom in the quaternary compound can be part of a heterocyclic ring. In all
of these compounds there is at least one aliphatic group, straight chain or branched,
containing from about 3 to 18 carbon atoms and at least one aliphatic substituent
containing an anionic water solubilizing group, e. g., carboxy, sulfonate, sulfate,
phosphate, or phosphonate.
[0073] Specific examples of zwitterionic surfactants which may be used are set forth in
U.S. Pat. No. 4,062,647, hereby incorporated by reference.
[0074] Preferably, the surfactant in the laundry compositions of the invention is anionic
and/or nonionic, especially linear alkylbenzene sulfonate, alkyl ether sulfate, alcohol
ethoxylates and mixtures thereof.
[0075] For higher foaming formulations (top-loading washing machines), mixtures of anionic
and nonionic surfactants are especially preferred, for optimum greasy stain and particulate
soil removal. When mixtures are used, the most effective mixtures employ anionic to
nonionic ratio of from 10: 1 to 1:10, preferably from 5:1 to 1:5, most preferably
from 3:1 to 1:3.
[0076] When low foaming formulations are desired, e.g., for front-loading machines, nonionic
surfactants are employed, in the absence of, or lower levels of, anionic surfactants,
alone or in combination with cationic surfactants and/or antifoams.
Optional Third Layer
[0077] The laundry compositions may include a third layer. A surfactant layer may contain
polar and non-polar components and thus may separate into two layers. Generally, however,
the third layer may be created, by adding an electrolyte to the aqueous layer, which
contains the predominant amount of the surfactant. The electrolyte may also be added
in order to increase the water content of the laundry compositions, without compromising
the integrity of he water soluble package.
Electrolyte
[0078] The electrolyte which may be included into the inventive compositions is selected
from the group of organic electrolytes, inorganic electrolytes and mixtures thereof.
[0079] Preferably, the electrolytes suitable for use in the present invention meet both
of the following criteria:
(1) they have a high salting out ability;
(2) they are able to lower water activity.
[0080] "Colored Inorganic electrolyte" contains a transition metal cation, such that the
electrolytes (salts) containing such cations will produce a colored aqueous solution.
Suitable cations include, but are not limited to cobalt, copper (cuprous and cupric),
chrome, nickel, iron (ferric and ferrous), zinc, zinc, manganese, vandium (vanadyl),
palladium and cadmium.
[0081] Suitable anions include but are not limited to sulphate, nitrate, fluoride, chloride,
bromide, iodide, acetate, tartrate, ammonium tartrate, benzenesulphonate, benzoate,
bicarbonate, carbonate, bisulphate, bisulphite, sulphate, sulphite, borate, borotartrate,
bromate, butyrate, chlorate, camphorate, chlorite, cinnamate, citrate, disilicate,
dithionate, ethylsulphate, ferricyanide, ferrocyanide, fluorosilicate, formate, glycerophosphate,
hydrogenphosphate, hydroxostannate, hypochlorite, hyponitrite, hypophosphite, iodate,
isobutyrate, lactate, laurate, metaborate, metasilicate, methionate, methylsulphate,
nitrite, oleate, orthophosphate, orthophosphite, orthosilicate, oxalate, perborate,
perchlorate, phosphate, polyfluoride, polychloride, polyiodide, polybromide, polysulphide,
polysulphate, polysulphite, salicylate, silicate, sorbate, stannate, stearate, succinate
or valerate, dichromate, chromate, nitrate, throyonate, permanganate, bromide, chloride,
fluoride, gluconate, phenolsulfate, selenate.
[0082] The use of the colored inorganic electrolyte results in formulations which contain
a colored electrolyte layer, with the color not leaking into the surfactant layer.
[0083] Furthermore, it is possible to have stable multi-colored formulations, with the colored
inorganic electrolyte in the electrolyte layer, and an organic dye in the surfactant
layer.
[0084] Suitable colored electrolytes include but are not limited to the following:
Compound |
Color |
Nickel Sulfate |
Green |
Cupric Sulfate |
Blue |
Potassium Dichromate |
Orange-red |
Ammonium Chromate |
Yellow |
Ammonium Chromic Sulfate |
Purple-red |
Tetraamminecopper Sulfate |
Blue |
Ammonium Ferric Sulfate |
Pale violet |
Chromic Potassium Sulfate |
Purple-red |
Ferric Sulfate |
Light yellow |
Ferrous Sulfate |
Brown-green |
Cobaltous Sulfate |
Red-pink |
Cobaltous Potassium Sulfate |
Purple |
Manganese Sulfate |
Red-pink |
Vanadyl Sulfate |
Blue |
Manganese Nitrate |
Pink-ish |
Ammonium Ferric Citrate |
Green-brown |
Ferric Nitrate |
Purple-white |
Ferric Sulfate |
Yellowish |
Cobaltous Throyonate |
Blue-green |
Merbromin |
Red |
Zinc Permanganate |
Violet-brown |
Ammonium Nickel Sulfate |
Blue-green |
Nickel Acetate |
Green |
Nickel Bromide |
Yellow-green |
Nickel Chloride |
Green |
Nickel Fluoride |
Yellow-green |
Potassium Tetracyanonickelate |
Orange |
Ammonium Cupric Chloride |
Yellow |
Cupric Acetate |
Green |
Cupric Chloride |
Blue-green |
Cupric Formate |
Pale blue |
Cupric Gluconate |
Light blue |
Cupric Glycinate |
Light blue |
Cupric Nitrate |
Pale green |
Cupric Perchlorite |
Pale green |
Cupric Phenolsulfate |
Blue-green |
Cupric Salicylate |
Blue-green |
Cupric Selenate |
Green-blue |
Cupric Tatrate |
Dark green |
Cuproxoline |
Brown |
Palladium Chloride |
Brown |
Cadmium Sulfide |
Yellow-orange |
[0085] Mixtures of electrolytes may be employed.
[0086] Electrolyte may be pre-formed or formed in situ.
[0087] Preferred electrolytes are selected from the group consisting of nickel, cupric and
cobaltous salts of sulfate and chloride, because these result in the most pleasing
colors for a laundry detergent.
[0088] "Organic electrolyte" as used herein means an electrolyte containing an organic cation.
"Organic cation," in turn, means a non-metal, positively charged ionic entity. Suitable
organic cations include but are not limited to ammonium, ammonium hydroxide, amines,
more preferably alkanolamines (e.g., monoethanolamine, diethanolamine, triethanolamine,
isopropylamine). Preferred organic electrolytes are selected from the group consisting
of monoethanolamine, triethanolamine, and ammonium oxide salts of citrate, carbonate,
bicarbonate, borate and sulfate. Monoethanolamine salt is the most effective. Monoethanolamine
citrate, monoethanolamine carbonate and monoethanolamine borate are the most preferred,
due to their ability to also function as builders and/or buffering agents in the detergent
composition. Monoethanolamine citrate is optimum, due to its optimum ability to salt
out a surfactant and/or reduce the water activity.
[0089] "Inorganic electrolyte" as used herein means an electrolyte containing an alkali
or alkaline earth metal cation. Suitable additional inorganic electrolytes include
but are not limited to sodium, potassium, lithium, magnesium, and calcium salts. Preferred
electrolytes are selected from the group consisting of sodium and potassium salts
of citrate, carbonate, bicarbonate, borate and sulfate. Sodium salt is the most cost-effective.
Sodium citrate, sodium carbonate and sodium borate are the most preferred, due to
their ability to also function as builders and/or buffering agents in the detergent
composition. Sodium citrate is optimum, due to its optimum ability to salt out a surfactant
and/or reduce the water activity.
[0090] Suitable anions for the inorganic electrolyte and the organic electrolyte are selected
from the list above.
[0091] When the third layer is desired, the liquid detergent composition of the invention
preferably includes from 1 to 50%, more preferably from 5 to 40%, most preferably
from 5 to 35%, and optimally from 10 to 30% of the electrolyte, in order to attain
a stable three-layered composition, at optimum cost. When mixtures of the colored
inorganic electrolyte are employed with additional inorganic or organic electrolytes,
the amount of the colored inorganic electrolyte is in the range of from 0.001 to 10%,
preferably from 0.01 to 5%, more preferably from 0.05 to 5%, optimally from 0.5 to
3%. The concentration of electrolyte to create a three-layered composition depends
on the surfactant concentration, the water amount and the identity of the electrolyte.
The concentration needed may be predicted by calculating the ionic strength of the
electrolyte at a particular concentration. It has been found as part of the present
invention that the preferred electrolytes and preferred concentrations are those that
have a calculated ionic strength of at least 4.2 preferably at least, 4.4, most preferably
at least 5.
[0092] Ionic strength represents interactions of ions with water molecules and other ions
in the solution. Ionic strength may be calculated as follows:
Σ=a sum for i number of ions
I = ionic strength
z = valence factor
m = molal concentration of the ith ion concentration
Hydrotrope
[0093] A particularly preferred optional ingredient is a hydrotrope, which prevents liquid
crystal formation. The addition of the hydrotrope thus aids the clarity/transparency
of the composition. The hydrotrope is typically included in the surfactant layer.
Suitable hydrotropes include but are not limited to propylene glycol, ethanol, urea,
salts of benzene sulphonate, toluene sulphonate, xylene sulphonate or cumene sulphonate.
Suitable salts include but are not limited to sodium, potassium, ammonium, monoethanolamine,
triethanolamine. Preferably, the hydrotrope is selected from the group consisting
of propylene glycol, xylene sulfonate, ethanol, and urea to provide optimum performance.
The amount of the hydrotrope is generally in the range of from 0 to 30%, preferably
from 0.5 to 20%, most preferably from 1 to 15%.
Protected Ingredient in the Top Layer
[0094] The top layer is preferably hydrophobic. The desired ingredient to be protected (e.g.,
benefit ingredient or a colorant) may form a continuous phase with the hydrophobic
ingredient (it can then be co-melted with the hydrophobic material) or it may form
a discontinuous (hydrophilic or incompatible hydrophobe) phase. In the latter case,
the hydrophobic material forms a continuous phase, which surrounds a discontinuous
phase. A hybrid of the two cases is also possible, i.e. both the continuous and discontinuous
phases contain benefit ingredient(s) and/ or colorant(s).
[0095] If present, the discontinuous phase of the hydrophobic layer is itself and/or comprises
a benefit agent and/or a colorant. In some embodiments of the invention, the discontinuous
phase is itself a benefit agent, e.g. a vegetable oil, such as sunflower seed oil,
in personal care compositions. In other embodiments, the discontinuous phase is itself
a colorant (e.g. a solid pigment). Still in other embodiments the discontinuous phase
serves as a vehicle for a benefit agent and/or colorant. And still in other embodiments
of the invention the discontinuous phase may itself be a benefit agent and/or colorant
and also further include an additional benefit agent and/or colorant. According to
the present invention, the discontinuous phase is immiscible with the continuous phase,
to prevent the exposure of the continuous phase to the environment outside the capsule.
The discontinuous phase may be a solution (aqueous or oil), an oil, an emulsion, a
dispersion, or a solid. The preferred form of the discontinuous phase is an oil or
a solution (oil or aqueous solution), due to the relative ease of incorporation of
the oil or the solution into the continuous phase. The layer may include more than
one discontinuous phase.
[0096] If the additional benefit agent/colorant is oil-soluble, than an oil is chosen to
carry the benefit agent/colorant in the discontinuous phase; if the benefit agent/colorant
is water-soluble, than the discontinuous phase is an aqueous solution. Of course,
as mentioned above, solids may be employed, without making a solution.
[0097] The discontinuous phase may be present in an amount of from 0.01 to 45%, more preferably
from 5 to 45%, most preferably from 10 to 40%, and optimally from 20 to 35%, (% by
volume of the hydrophobic layer) in order to deliver sufficient benefit agent/colorant,
provide an adequate protection for the benefit agent/colorant and to maintain the
ease of processing.
[0098] For a hydrophobic layer which contains a discontinuous phase, the continuous phase
may sometimes be referred to hereinafter as a "shell" or "shell material".
[0099] For simplicity, the material entrapped within the shell, either directly, or as a
discontinuous phase, will be referred to as an "enzyme". However, it is within the
scope of the present disclosure that materials other than enzymes can be encapsulated
by the techniques disclosed herein. The choice of the benefit agent depends largely
on whether the final consumer composition is a detergent composition or a personal
care composition. As mentioned above, the continuous or discontinuous phase itself
may represent a benefit agent, so it is not necessary that an additional benefit agent
be present. Thus, an additional benefit agent may be present in an amount of from
0 to 100%, preferably 0.01 to 50%, more preferably 0.1 to 20%, by weight of the discontinuous
phase.
[0100] Typical benefit agents include, but are not limited to a bleach, a bleach precursor,
a surfactant, an enzyme, a whitening agent, a fabric softener, an anti-wrinkle compound,
a dye fixative, dye transfer inhibitors, anti-redeposition polymers, soil release
polymers, an anti-foam agent, a perfume, a silicone oil, a vegetable oil, a and mixtures
thereof.
Enzymes
[0101] Enzymes which may be used in the subject invention are described in greater detail
below. Enzyme is typically included in an amount from 0.05 to 5%, preferably 0.05
to 3%. The enzyme is preferably contained predominantly in the top layer, which is
preferably hydrophobic, with the volume ratio of bottom to top layer of at least 90:10,
preferably 95:5. Thus, generally, at least 90%, preferably at least 90% of the enzyme
is in the top layer.
[0102] If a lipase is used, the lipolytic enzyme may be either a fungal lipase producible
by Humicola lanuginosa and Thermomyces lanuginosus, or a bacterial lipase which show
a positive immunological cross-reaction with the antibody of the lipase produced by
the microorganism Chromobacter viscosum var. lipolyticum NRRL B-3673. This microorganism
has been described in Dutch patent specification 154,269 of Toyo Jozo Kabushiki Kaisha
and has been deposited with the Fermentation Research Institute, Agency of Industrial
Science and Technology, Ministry of International Trade and Industry, Tokyo, Japan,
and added to the permanent collection under nr. KO Hatsu Ken Kin Ki 137 and is available
to the public at the United States Department of Agriculture, Agricultural Research
Service, Northern Utilization and Development Division at Peoria, Ill., USA, under
the nr. NRRL B-3673. The lipase produced by this microorganism is commercially available
from Toyo Jozo Co., Tagata, Japan, hereafter referred to as "TJ lipase". These bacterial
lipases should show a positive immunological cross-reaction with the TJ lipase antibody,
using the standard and well-known immune diffusion procedure according to Ouchterlony
(Acta. Med. Scan., 133. pages 76-79 (1930).
[0103] The preparation of the antiserum is carried out as follows:
[0104] Equal volumes of 0.1 mg/ml antigen and of Freund's adjuvant (complete or incomplete)
are mixed until an emulsion is obtained. Two female rabbits are injected 45 with 2
ml samples of the emulsion according to the following scheme:
day 0:antigen in complete Freund's adjuvant
day 4:antigen in complete Freund's adjuvant
day 32:antigen in incomplete Freund's adjuvant
day 64:booster of antigen in incomplete Freund's adjuvant.
[0105] The serum containing the required antibody is prepared by centrifugation of clotted
blood, taken on day 67.
[0106] The titre of the anti-TJ-Iipase antiserum is determined by the inspection of precipitation
of serial dilutions of antigen and antiserum according to the Ouchteriony procedure.
A dilution of antiserum was the dilution that still gave a visible precipitation with
an antigen concentration of 0.1 mg/ml.
[0107] All bacterial lipases showing a positive immunological cross reaction with the TJ-lipase
antibody as hereabove described are lipases suitable in this embodiment of the invention.
Typical examples thereof are the lipase ex Pseudomonas fluorescens IAM 1057 (available
from Amano Pharmaceutical Co., Nagoya, Japan, under the trade-name Amano-P lipase),
the lipase ex Pseudomonas fragi PERM P 1339 (available under the trade- name Amano
B), the lipase ex Pseudomonas nitroreducens var. lipolyticum FERM P1338, the lipase
ex Pseudomonas sp. (available under the trade- name Amano CES), the lipase ex Pseudomonas
cepacia, lipases ex Chromobacter viscosum, e.g. Chromobacter viscosum var. lipolyticum
NRRL B-3673, commercially available from Toyo Jozo Co., Tagata, Japan; and further
Chromobacter viscosum lipases from U.S. Biochemical Corp. USA and Diosynth Co., The
Netherlands, and lipases ex Pseudomonas gladioli.
[0108] An example of a fungal lipase as defined above is the lipase ex Humicola lanuginosa
available from Amano under the tradename Amano CE; the lipase ex Humicola lanuginosa
as described in the aforesaid European Patent Application 0,258,068 (NOVO), as well
as the lipase obtained by cloning the gene from Humicola lanuginosa and expressing
this gene in Aspergillus oryzae, commercially available from NOVO industri A/S under
the tradename "Lipolase". This lipolase is a preferred lipase for use in the present
invention.
[0109] While various specific lipase enzymes have been described above, it is to be understood
that any lipase which can confer the desired lipolytic activity to the composition
may be used and the invention is not intended to be limited in any way by specific
choice of lipase enzyme.
[0110] The lipases of this embodiment of the invention are included in the liquid detergent
composition in such an amount that the final composition has a lipolytic enzyme activity
of from 100 to 0.005 LU/ml in the wash cycle, preferably 25 to 0.05 LU/ml when the
formulation is dosed at a level of about 0.1-10, more preferably 0.5-7, most preferably
1-2 g/liter.
[0111] A Lipase Unit (LU) is that amount of lipase which produces 1/mmol of titratable fatty
acid per minute in a pH state under the following conditions: temperature 30°C.; pH=9.0;substrate
is an emulsion of 3.3 wt. % of olive oil and 3,3% gum arabic, in the presence of 13
mmol/l Ca
2+ and 20 mmol/l NaCl in 5 mmol/l Trisbuffer.
[0112] Naturally, mixtures of the above lipases can be used. The lipases can be used in
their non-purified form or in a purified form, e.g. purified with the aid of well-known
absorption methods, such as phenyl sepharose absorption techniques.
[0113] If a protease is used, the proteolytic enzyme can be of vegetable, animal or microorganism
origin. Preferably, it is of the latter origin, which includes yeasts, fungi, molds
and bacteria.
[0114] Particularly preferred are bacterial subtilisin type proteases, obtained from e.g.
particular strains of B. subtilis and B licheniformis. Examples of suitable commercially
available proteases are Alcalase, Savinase, Esperase, all of NOVO Industri A/S; Maxatase
and Maxacal of Gist-Brocades; Kazusase of Showa Denko; BPN and BPN' proteases and
so on. The amount of proteolytic enzyme, included in the composition, ranges from
0.05-50,000 GU/mg. preferably 0.1 to 50 GU/mg, based on the final composition. Naturally,
mixtures of different proteolytic enzymes may be used.
[0115] While various specific enzymes have been described above, it is to be understood
that any protease which can confer the desired proteolytic activity to the composition
may be used and this embodiment of the invention is not limited in any way be specific
choice of proteolytic enzyme.
[0116] In addition to lipases or proteases, it is to be understood that other enzymes such
as cellulases, oxidases, amylases, peroxidases and the like which are well known in
the art may also be used with the composition of the invention. The enzymes may be
used together with cofactors required to promote enzyme activity, i.e., they may be
used in enzyme systems, if required. It should also be understood that enzymes having
mutations at various positions (e.g., enzymes engineered for performance and/or stability
enhancement) are also contemplated by the invention. One example of an engineered
commercially available enzyme is Durazym from Novo.
[0117] In the case of an enzyme, the discontinuous phase is an aqueous solution of the enzyme.
The aqueous enzyme solution may optionally contain a low HLB surfactant, in order
to further enhance the formation of the emulsion. The level of the surfactant can
be reduced or even eliminated, particularly if suitable agitation is used. Furthermore,
the need for surfactant is entirely eliminated if the shell material is a mixture
of thermoplastic polymer with oil, rather than a wax/oil mixture.
Colorant
[0118] The colorant may be a dye or a pigment. Dyes are preferable, since they are water-soluble
and thus are more easily incorporated into the layer emulsion, compared to pigments
which are typically not water-soluble. Most preferably, a water-soluble dye is entrapped,
alone or in the mixture with a benefit agent, within a transparent, uncolored continuous
phase.
[0119] Most preferably, the layer is an emulsion or dispersion containing both the benefit
agent and the colorant, within a transparent continuous phase, to provide a visual
signal to the consumer that a composition contains an additional beneficial ingredient.
[0120] The emulsion/dispersion may be prepared by any known method, but preferably the emulsion
or dispersion is prepared by mixing the continuous and discontinuous phases, the latter
being or containing the ingredient to be encapsulated, e.g. bleach solution or a vegetable
oil. In the preferred embodiment, the co-polymer is melted, mixed with oil, then the
discontinuous phase is added, with stirring (agitation), to ensure uniform mixing
of the ingredients. The resulting emulsion/dispersion is preferably kept at a temperature
in the range from 40°C to 95°C. Most preferably, the use of direct heat is avoided.
A most preferred temperature range is from 60°C to 75°C.
POSITION OF THE LAYERS
[0121] Position of the hydrophobic layer is defined by the relative densities of the layers.
Most liquid detergents have a density of 1 or slightly below or above, i.e. in the
range of from 0.9-1.1 g/L. Enzyme emulsions typically have a lower density than a
liquid detergent composition. In this case, the density of the enzyme capsule/emulsion
is less than 1, as a result of the density of the hydrophobic ingredient ranging from
0.8 to 0.9 g/L. Thus, the hydrophobic layer will typically float to the top, as is
preferred according to the present invention, to minimize the interface area between
the ingredient to be protected in the hydrophobic layer and the aqueous layer.
[0122] The preferred laundry composition may further include one or more well-known laundry
ingredients, such as builders (from 0.1 to 20%), anti-redeposition agents, fluorescent
dyes, perfumes, soil-release polymers, colorant, enzymes, buffering agents, antifoam
agents, UV-absorber, etc.
[0123] Examples of suitable inorganic alkaline detergency builders which may be used are
water-soluble alkali metal phosphates, polyphosphates, borates, silicates and also
carbonates. Specific examples of such salts are sodium and potassium triphosphates,
pyrophosphates, orthophosphates, hexametaphosphates, tetraborates, silicates, and
carbonates.
[0124] Examples of suitable organic alkaline detergency builder salts are: (1) water-soluble
amino polycarboxylates, e.g., sodium and potassium ethylenediaminetetraacetates, nitrilotriacetates
and N-(2 hydroxyethyl)-nitrilodiacetates; (2) water-soluble salts of phytic acid,
e.g., sodium and potassium phytates (see U.S. Pat. No. 2,379,942); (3) water-soluble
polyphosphonates, including specifically, sodium, potassium and lithium salts of ethane-1-hydroxy-1,1-diphosphonic
acid; sodium, potassium and lithium salts of ethylene diphosphonic acid; sodium, potassium
and lithium salts of ethylene diphosphonic acid; and sodium, potassium and lithium
salts of ethane-1,1,2-triphosphonic acid. Other examples include the alkali metal
salts of ethane-2-carboxy-1,1-diphosphonic acid hydroxymethanediphosphonic acid, carboxyldiphosphonic
acid, ethane-1-hydroxy-1,1,2-triphosphonic acid, ethane-2-hydroxy-1,1,2- triphosphonic
acid, propane-1,1,3,3-tetraphosphonic acid, propane-1,1,2, 3-tetraphosphonic acid,
and propane-1,2,2,3-tetra-phosphonic acid; (4) water-soluble salts of polycarboxylates
polymers and copolymers as described in U.S. Pat. No. 3,308,067.
[0125] In addition, polycarboxylate builders can be used satisfactorily, including water-soluble
salts of mellitic acid, citric acid, and carboxymethyloxysuccinic acid, salts of polymers
of itaconic acid and maleic acid, tartrate monosuccinate, tartrate disuccinate and
mixtures thereof (TMS/TPS).
[0126] Certain zeolites or aluminosilicates can be used. One such aluminosilicate which
is useful in the compositions of the invention is an amorphous water-insoluble hydrated
compound of the formula Na [(AlO
2) .y.SiO
2), wherein x is a number from 1.0 to 1.2 and y is 1, said amorphous material being
further characterized by a Mg++ exchange capacity of from about 50 mg eq. CaCO
3 /g. and a particle diameter of from about 0.01 mm to about 5 mm. This ion exchange
builder is more fully described in British Patent No. 1,470,250.
[0127] A second water-insoluble synthetic aluminosilicate ion exchange material useful herein
is crystalline in nature and has the formula Na
z [(AlO
2)
y (SiO
2)]
x H
2 O, wherein z and y are integers of at least 6; the molar ratio of z to y is in the
range from 1.0 to about 0.5, and x is an integer from about 15 to about 264; said
aluminosilicate ion exchange material having a particle size diameter from about 0.1
mm to about 100 mm; a calcium ion exchange capacity on an anhydrous basis of at test
about 200 milligrams equivalent of CaCO
3 hardness per gram; and a calcium exchange rate on an anhydrous basis of at least
about 2 grains/gallon/minute/gram. These synthetic aluminosilicates are more fully
described in British Patent No. 1,429,143.
[0128] Optical brighteners for cotton, polyamide and polyester fabrics can be used. Suitable
optical brighteners include Tinopal, stilbene, triazole and benzidine sulfone compositions,
especially sulfonated substituted triazinyl stilbene, sulfonated naphthotriazole stilbene,
benzidene sulfone, etc., most preferred are stilbene and triazole combinations. A
preferred brightener is Stilbene Brightener N4 which is a dimorpholine dianilino stilbene
sulfonate.
[0129] Anti-foam agents, e.g. silicone compounds, such as Silicane L 7604, can also be added
in small effective amounts.
[0130] Bactericides, e.g. tetrachlorosalicylanilide and hexachlorophene, fungicides, dyes,
pigments (water dispersible), preservatives, e.g. formalin, ultraviolet absorbers,
anti-yellowing agents, such as sodium carboxymethyl cellulose, pH modifiers and pH
buffers, color safe bleaches, perfume and dyes and bluing agents such as Iragon Blue
L2D, Detergent Blue 472/372 and ultramarine blue can be used.
[0131] Also, soil release polymers and cationic softening agents may be used.
[0132] The list of optional ingredients above is not intended to be exhaustive and other
optional ingredients which may not be listed, but are well known in the art, may also
be included in the composition.
[0133] The pH of the inventive compositions is generally in the range of from 2.5 to 12.5,
preferably in the range of from 4 to 10, most preferably from 6 to 9, in order to
attain optimum laundry cleaning.
[0134] Preferably, the detergent composition is a transparent/translucent two-colored composition
packaged in the transparent/translucent body.
[0135] The packages of the invention may be filled in any suitable way. Preferably, the
liquid detergent composition is premixed (both components) and filled in the same
manner as a single phase composition would be. The composition may also be filled
component by component.
[0136] In use, the package is mixed with water (e.g., inside a laundry machine or a dishwasher),
in order to dissolve the body and to release the contents of the package.
[0137] The following specific examples further illustrate the invention, but the invention
is not limited thereto.
EXAMPLE 1
[0138]
Ingredient |
Supplier |
% of each layer |
Top layer (10% of the whole composition) |
Mineral oil |
Witco |
65 |
Paraffin wax |
Penreco |
15 |
Silicon oil |
Dow Corning |
10 |
Antifoam agent |
Dow Corning |
10 |
|
|
|
Bottom layer (90% of the whole composition) |
Water |
|
6 |
Propylene glycol |
Eastman Chemical |
20 |
Alcohol ethoxylate nonionic surfactant, Neodol® 25-9 |
Shell Chemical |
25 |
MEA-LAS (monoethanolamine linear alkylbenzene sulfonate) |
Stepan |
40 |
Miscellaneous |
|
9 |
[0139] The top layer was prepared by melting paraffin wax at 60°C with mineral oil, followed
by emulsifying silicon oil and antifoam agent in the mixture. At 20°C, the top layer
was a thick emulsion. The bottom layer was prepared by following the order listed
in the above formulation. MEA-LAS was neutralized in-situ by reacting monoethanolamine
with LAS acid. First, a PVA pouch was prepared by heat-sealed the longitudinal edges
to form a tube followed by heat-sealed the bottom by using a Mono-Sol M4045 PVA film.
Forty-five grams of bottom layer and five grams of the top layer were filled in the
prepared PVA pouch. The pouch then heat-sealed orthogonal to the bottom sealed. The
top layer floated to the top and formed a visible layer.
EXAMPLE 2
[0140]
Ingredient |
Supplier |
% by weight of layer |
Top Layer (3% of the whole composition) |
Mineral oil |
Witco |
61 |
Paraffin wax |
Penreco |
19 |
Properase® 1600L |
Genencor |
20 |
|
|
|
Middle layer (47% of the whole composition) |
Water |
|
9.0 |
Xylene Sulfonate, 25% |
Stepan |
10.5 |
Propylene Glycol |
Eastman Chemical |
10.0 |
Alcohol Ethoxylate Nonionic Surfactant, Neodol® 25-9 |
Shell Chemical |
16.8 |
Sodium LAS |
Stepan |
16.8 |
Sodium alcohol ethoxylate sulfate, 59.39% |
Stepan |
27.6 |
Miscellaneous |
|
9.3 |
|
|
|
Bottom layer (50% of the whole formulation) |
|
|
Water |
|
40 |
MEA-Citrate (monoethanolamine citrate) |
Haarman and Reimer |
50 |
Monoethanolamine |
Dow Chemical |
10 |
|
|
|
[0141] The top layer was prepared by melting paraffin wax at 45°C with mineral oil, followed
by emulsifying Properase® 1600L in the mixture. After the emulsification, the emulsion
was cooled to 20°C to prevent the excess loss of enzyme. The top layer was a thick
emulsion. The other two layers were prepared by following the order listed in the
above table. MEA-citrate was neutralized in-situ by reacting monoethanolamine with
citric acid. First, a PVA (polyvinyl alcohol) pouch was prepared by heat-sealed the
longitudinal edges to form a tube followed by heat-sealed the bottom by using a Mono-Sol
M4045 PVA film. Twenty-five grams of bottom layer, 23.5 grams of middle layer and
15 grams of the top layer were filled in the prepared PVA pouch. The pouch then heat-sealed
orthogonal to the bottom sealed. The top layer floated to the top and minimized the
interface between the top and the middle layers. Three visible layers were formed.