U.S. patent application number 12/699951 was filed with the patent office on 2010-06-03 for powder detergent granule containing acidic water-soluble polymer and manufacturing method thereof.
Invention is credited to Kee-Heon Cho, Min-Seok Cho, Hyun-Chang Kim, Sang-Woon Kwak, Young-Kee Oh.
Application Number | 20100137185 12/699951 |
Document ID | / |
Family ID | 39880302 |
Filed Date | 2010-06-03 |
United States Patent
Application |
20100137185 |
Kind Code |
A1 |
Cho; Min-Seok ; et
al. |
June 3, 2010 |
POWDER DETERGENT GRANULE CONTAINING ACIDIC WATER-SOLUBLE POLYMER
AND MANUFACTURING METHOD THEREOF
Abstract
The present invention relates to powder detergent granules that
are substantially free of a water-insoluble component such as
zeolite or silica, a method for manufacturing the powder detergent
granules and a copolymer having various properties useful as a
detergent component. The powder detergent granules of the present
invention are substantially free of a water-insoluble component,
and thus exhibit good solubility and washing performance (stain
removal performance) in cold water, do not leave residue after
laundry, and reduce the likelihood of a caking phenomenon during
manufacture and storage. And, the powder detergent granules of the
present invention are substantially free of zeolite or silica that
absorbs a liquid component, but are capable of accommodating a
considerable amount of liquid surfactant. Further, a copolymer
comprising acrylic acid monomer unit and
2-acrylamido-2-methylpropane sulfonic acid monomer unit, an acidic
water-soluble polymer of the present invention, is useful as a
detergent component in various aspects.
Inventors: |
Cho; Min-Seok; (Daejeon,
KR) ; Oh; Young-Kee; (Daejeon, KR) ; Cho;
Kee-Heon; (Daejeon, KR) ; Kim; Hyun-Chang;
(Daejeon, KR) ; Kwak; Sang-Woon; (Daejeon,
KR) |
Correspondence
Address: |
STROOCK & STROOCK & LAVAN LLP
180 MAIDEN LANE
NEW YORK
NY
10038
US
|
Family ID: |
39880302 |
Appl. No.: |
12/699951 |
Filed: |
February 4, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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|
12033503 |
Feb 19, 2008 |
|
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12699951 |
|
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60894275 |
Mar 12, 2007 |
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Current U.S.
Class: |
510/475 ;
526/287 |
Current CPC
Class: |
C08F 228/02 20130101;
C11D 11/04 20130101; C02F 5/10 20130101; C11D 3/3784 20130101; C11D
3/378 20130101; C11D 17/06 20130101 |
Class at
Publication: |
510/475 ;
526/287 |
International
Class: |
C11D 3/37 20060101
C11D003/37; C08F 228/02 20060101 C08F228/02 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 2007 |
KR |
10-2007-0017623 |
Sep 17, 2007 |
KR |
10-2007-0094173 |
Claims
1-12. (canceled)
13. A copolymer comprising an acrylic acid monomer unit and
2-acrylamido-2-methylpropane sulfonic acid monomer unit represented
by the following Chemistry FIG. 3: ##STR00006##
14. The copolymer according to claim 13, wherein a weight ratio of
acrylic acid monomer unit to 2-acrylamido-2-methylpropane sulfonic
acid monomer unit is 95:5 to 80:20, and wherein a pH of the
copolymer is 0.1 to 3 when measured as 50% aqueous solution and a
viscosity of the copolymer is 300 to 2000 cP at 25.degree. C.
15. A composition, comprising the copolymer defined in claim
13.
16-19. (canceled)
20. The composition of claim 15, wherein the composition is for
making a detergent product.
21. The composition of claim 20 wherein a content of
water-insoluble components is 5% weight or less based on a total
weight of the detergent product.
22. The composition of claim 15, wherein the composition is for
making a metal ion binding product or hard-water softening
product.
23. The composition of claim 22 wherein the metal ion is a calcium
ion.
Description
TECHNICAL FIELD
[0001] The present invention relates to powder detergent granules
exhibiting good solubility in cold water, not leaving residue after
laundry and having improved caking phenomenon prevention,
manufacturing method thereof, and a new polymer useful as a
detergent component.
BACKGROUND ART
[0002] Generally, a powder detergent has better washing effect in
soft water than in hard water containing more magnesium and calcium
ions, and by this reason, the powder detergent contains a
hard-water softener, for example zeolite.
[0003] The conventional water softener, zeolite is insoluble in
water, and after laundry, zeolite builds up in clothes and requires
considerable time to bind ions, thereby retarding a softening
effect, and thus the calcium ions remaining during laundry are
bonded to carbonate ions that are ionized from an alkali builder to
form calcium carbonate, which builds up in a washing tank of a
washing machine, a heating coil and clothes. To overcome this
problem, zeolite is used in the form of fine granules. However, the
problem is not completely solved.
DISCLOSURE
Technical Problem
[0004] Therefore, it is an object of the present invention to
provide powder detergent granules that have good washing capability
without use of a water-insoluble component such as zeolite or
silica, and have good solubility in cold water and improved
functions of soil redeposition prevention and water softening, and
to provide a method for manufacturing the powder detergent granules
simply and effectively.
[0005] It is another object of the present invention to provide
water-soluble powder detergent granules capable of preventing a
caking phenomenon and accommodating a considerable amount of liquid
detergent component without a substantial use of a water-insoluble
component such as zeolite or silica, and to provide a method for
manufacturing the water-soluble powder detergent granules.
[0006] It is yet another object of the present invention to provide
a new copolymer having useful properties in aspect of metal ion
binding, soil removal and water solubility, and to provide a new
use of the polymer as a detergent component.
Technical Solution
[0007] In order to achieve the above-mentioned objects, the present
invention provides powder detergent granules formed by mixing 0.1
to 15 parts by weight of an acidic water-soluble polymer with 10 to
70 parts by weight of an alkali builder to carry out a
neutralization reaction, and preferably the acidic water-soluble
polymer is a polymer comprising at least one unit selected from the
group consisting of a monomer unit containing a carboxylic acid
group, a monomer unit containing a sulfonic acid group and a
monomer unit containing a phosphoric acid group, more preferably a
copolymer comprising a monomer unit containing a carboxylic acid
group and a monomer unit containing a sulfonic acid group.
[0008] And, the present invention provides a method for
manufacturing powder detergent granules that are dried using heat
generated by a neutralization reaction between an acid
water-soluble polymer and an alkali builder, comprising (S1)
preparing an acidic water-soluble polymer, most preferably a
copolymer comprising a monomer unit containing a carboxylic acid
group and a monomer unit containing a sulfonic acid group, and an
alkali builder; (S2) putting 0.1 to 15 parts by weight of the
acidic water-soluble polymer and 10 to 70 parts by weight of the
alkali builder into a mixer; and (S3) uniformly mixing the
components of the step (S2) put into the mixer.
[0009] According to the present invention, the method for
manufacturing powder detergent granules may eliminate the need of
or reduce usage of a counter-current flow spray dryer or a steam
spray mixer that is complicated and expensive and is used after the
neutralization reaction, thereby resulting in a simple and
economical manufacturing process.
[0010] According to the present invention, the powder detergent
granules are manufactured by the neutralization reaction between
the acidic water-soluble polymer and the alkali builder. The
present invention is based on the principle that the neutralization
reaction generates heat for drying the powder detergent granules
and gas for creating pores in the powder detergent granules,
thereby the manufacturing method of the present invention can
improve solubility of the powder detergent granules.
[0011] And, the present invention provides a copolymer comprising
acrylic acid monomer unit and 2-acrylamido-2-methylpropane sulfonic
acid monomer unit, which has good effect of metal ion binding, in
particular calcium ion and magnesium ion, and provides a detergent
composition comprising the copolymer. Preferably, a weight ratio of
the acrylic acid monomer unit to 2-acrylamido-2-methylpropane
sulfonic acid monomer unit is 95:5 to 80:20, more preferably 95:5
to 90:10.
[0012] Also, the present invention provides a metal ion binding
composition comprising the above-mentioned copolymer, preferably a
calcium ion binding composition.
[0013] Further, the present invention provides a hard-water
softening composition comprising the above-mentioned copolymer.
DESCRIPTION OF DRAWINGS
[0014] FIG. 1 is a graph showing results of change of calcium
binding capacity according to a weight ratio of acrylic acid
monomer unit and 2-acrylamido-2-methylpropane sulfonic acid monomer
unit in a copolymer of Chemistry FIG. 3 of the present
invention.
BEST MODE
[0015] Hereinafter, powder detergent granules, a method for
manufacturing the powder detergent granules and an inventive
copolymer useful as a detergent component according to the present
invention will be described in detail.
[0016] The powder detergent granules that are substantially free of
a water-insoluble component such as zeolite or silica, comprise 0.1
to 15 parts by weight of an acidic water-soluble polymer.
[0017] The meaning that the water-insoluble component such as
zeolite or silica is `substantially excluded` or `substantially
does not exist` is herein construed as that the water-insoluble
component such as zeolite or silica is completely not used in the
manufacture of the powder detergent granules or is used 10 weight %
or less based on a total weight of the powder detergent granules,
preferably 5 weight % or less, more preferably 1 weight % or
less.
[0018] The acidic water-soluble polymer may be a homopolymer or a
copolymer comprising at least one monomer unit selected from the
group consisting of a monomer unit containing a carboxylic acid
group, a monomer unit containing a sulfonic acid group and a
monomer unit containing a phosphoric acid group, and the copolymer
may be various types of copolymers, for example a random copolymer,
an alternating copolymer, a block copolymer or a graft
copolymer.
[0019] According to the present invention, the copolymer includes a
heteropolymer or a terpolymer that consists of two or three kinds
of monomers, respectively.
[0020] And, according to the present invention, the powder
detergent granules may comprise at least two kinds of acidic
water-soluble polymers, and a monomer of each of the acidic
water-soluble polymers may simultaneously contain at least two acid
groups selected from the group consisting of a carboxylic acid
group, a sulfonic acid group and a phosphoric acid group.
[0021] And, according to the present invention, in the case that
the acidic water-soluble polymer is a copolymer comprising at least
two different units selected from the group consisting of a monomer
unit containing a carboxylic acid group, a monomer unit containing
a sulfonic acid group and a monomer unit containing a phosphoric
acid group, the powder detergent granules exhibit better effects of
washing and caking phenomenon prevention. In particular, in the
case that the acidic water-soluble polymer is a copolymer
comprising a monomer unit containing a carboxylic acid group and a
monomer unit containing a sulfonic acid group, the powder detergent
granules have faster solubility in cold water, better washing
capability and more effective caking phenomenon prevention.
[0022] In greater detail, the acidic water-soluble polymer
according to the present invention may be a polymer comprising at
least one monomer unit represented by the following Chemistry FIG.
1 or 2, more specifically a homopolymer or a copolymer, however the
present invention is not limited thereto.
##STR00001##
[0023] where R.sub.1 each is independently a carboxylic acid group,
a sulfonic acid group (SO.sub.3.sup.-H.sup.+), a phosphoric acid
group (PO.sub.4.sup.-H.sup.+), a phosphonic acid group
(PO.sub.3.sup.-H.sup.+), or salts thereof.
##STR00002## ##STR00003## ##STR00004##
[0024] As concrete examples, the acidic water-soluble polymer may
be alpha-hydroxylic acid polymer, tetramethylene-1,2-dicarboxylic
acid polymer, 4-methoxytetramethylene-1,2-dicarboxylic acid
polymer, styrene sulfonic acid polymer, styrene phosphoric acid
polymer, styrene polymer, or combinations thereof, and may be a
copolymer comprising at least two monomer units selected from the
group consisting of alpha-hydroxylic acid,
tetramethylene-1,2-dicarboxylic acid,
4-methoxytetramethylene-1,2-dicarboxylic acid, styrene sulfonic
acid, styrene phosphoric acid and styrene, or combinations
thereof.
[0025] In the above homopolymer or copolymer, a sulfonic acid or
carboxylic acid is connected to a side chain of a polymer in the
shape of an acid and reacted with a base material, so that a
neutralization reaction occurs to form a polymer salt, thereby
manufacturing powder detergent granules without use of zeolite.
And, as moisture is removed in the shape of a polymer, the shape is
maintained due to physical properties of the polymer, and thus
pores created by gas generated in the neutralization reaction can
be maintained.
[0026] Preferably, a pH of 0.1% (w/w) aqueous solution of the
acidic water-soluble polymer is 1 to 3. And, as described above, to
maintain the pores created by gas generated in the neutralization
reaction, preferably the acidic water-soluble polymer has a
specific average molecular weight range. That is, in the case that
the acidic water-soluble polymer has an average molecular weight of
3,000 to 60,000, it is easier to manufacture the powder detergent
granules. In the case that the acidic water-soluble polymer has an
average molecular weight of 10,000 to 40,000, it is much easier to
manufacture the powder detergent granules.
[0027] And, in the case that the acidic water-soluble polymer is a
copolymer comprising a monomer unit containing a carboxylic acid
group and a monomer unit containing a sulfonic acid group, a ratio
of the carboxylic acid group to the sulfonic acid group is 99:1 to
50:50, preferably 95:5 to 50:50, more preferably 95:5 to 80:20,
most preferably 95:5 to 90:10. In the case that a ratio of the
sulfonic acid group is low, a solubility promoting effect may be
insignificant, and in the case that a ratio of the sulfonic acid
group is high, the whole color of the polymer may become deep
brown.
[0028] And, the present invention is based on the fact that, a
copolymer comprising acrylic acid monomer unit and
2-acrylamido-2-methylpropane sulfonic acid monomer unit, one of the
acidic water-soluble polymer, is very useful as a detergent
component. The above-mentioned copolymer is superior to other kinds
of acidic water-soluble polymers in aspect of metal ion binding,
soil removal, soil redeposition prevention, solubility in water,
easiness of manufacturing powder detergent granules and phase
stability in mixing with other detergent component.
[0029] According to the present invention, the above-mentioned
copolymer has better effect of metal ion binding, in particular,
calcium and magnesium ions than other kinds of acidic water-soluble
polymers. General water contains a lot of calcium ions and
magnesium ions that should be excluded to prevent reduction of
washing capability, and in this regard, the above-mentioned
copolymer of the present invention is useful for the powder
detergent granules. And, the powder detergent granules are dried by
heat generated from the neutralization reaction between the
water-soluble acidic polymer and the alkali builder, and in this
regard, the above-mentioned copolymer of the present invention is
very useful in manufacturing the powder detergent granules.
[0030] For example, in calcium binding capacity evaluation using
CaCO.sub.3 [2 g of a sample is dissolved in 100 ml of a distilled
water, 10 ml of 2% NaCO.sub.3 is added, pH is adjusted to 11 using
0.1N--NaOH, and then the solution is titrated with 4.4%
Ca(AC).sub.2H.sub.2O solution. End point is a time that opaque
turbidity emergence is maintained (it does not disappear even under
a strong agitation)], it is found that the copolymer comprising
acrylic acid monomer unit and 2-acrylamido-2-methylpropane sulfonic
acid monomer unit has higher metal ion binding capability about 2.1
or 1.6 times than an acrylic acid homopolymer or a copolymer
comprising acrylic acid monomer unit and styrenesulfonic acid
monomer unit. And, in dissolution time evaluation using 5.degree.
C. of water, it is found that the copolymer comprising acrylic acid
monomer unit and 2-acrylamido-2-methylpropane sulfonic acid monomer
unit is dissolved much faster than an acrylic acid homopolymer or a
copolymer comprising an acrylic acid monomer unit and a
styrenesulfonic acid monomer unit.
[0031] In consideration of various properties as a detergent
component, preferably the copolymer comprising acrylic acid monomer
unit and 2-acrylamido-2-methylpropane sulfonic acid monomer unit
has a weight ratio (A:B) of acrylic acid monomer unit (A) to
2-acrylamido-2-methylpropane sulfonic acid monomer unit (B) of 95:5
to 80:20, more preferably 95:5 to 90:10. And, to exhibit optimum
effect as a detergent component, preferably the copolymer
comprising acrylic acid monomer unit and
2-acrylamido-2-methylpropane sulfonic acid monomer unit has an
average molecular weight of 2,000 to 100,000, more preferably 3,000
to 5,000, or 10,000 to 30,000 or 50,000 to 90,000.
[0032] In greater detail, as shown in FIG. 1, as a weight ratio of
2-acrylamido-2-methylpropane sulfonic acid monomer unit increases,
the calcium binding capacity increased, and preferably a weight
ratio of acrylic acid monomer unit to 2-acrylamido-2-methylpropane
sulfonic acid monomer unit is 95:5 to 80:20. In case the weight
ratio of 2-acrylamido-2-methylpropane sulfonic acid monomer unit is
higher than the above-mentioned weight ratio, it was not economical
because the calcium binding capacity in proportion to manufacturing
costs was low, and in case the weight ratio of
2-acrylamido-2-methylpropane sulfonic acid monomer unit is lower
than the above-mentioned weight ratio, the calcium binding capacity
was somewhat poor.
[0033] And, as a detergent component useful in manufacturing the
powder detergent granules, preferably the copolymer comprising
acrylic acid monomer unit and 2-acrylamido-2-methylpropane sulfonic
acid monomer unit has a pH of 0.1 to 3 when measured as 50% aqueous
solution according to KSM0011 method and a viscosity of 300 to
2,000 cP at 25.degree. C. when measured according to KSM3825 (#B
Viscometer RVT (#3/50)) method.
[0034] A preferred example of the copolymer comprising acrylic acid
monomer unit and 2-acrylamido-2-methylpropane sulfonic acid monomer
unit according to the present invention may be represented by the
following Chemistry FIG. 3, and may be manufactured using a radical
polymerization method that is a general polymerization method of an
acrylic acid, which is well known in the art. At this time, for
easy application to a laundry detergent, viscosity of the copolymer
should be controlled, and the conventional viscosity control using
an organic solvent such as isopropyl alcohol (IPA) has an odor
problem, however the present invention controls the viscosity by
control of polymerization temperature, not by use of the organic
solvent, thereby preventing the odor problem.
##STR00005##
[0035] Therefore, the present invention provides the powder
detergent granules comprising the copolymer comprising acrylic acid
monomer unit and 2-acrylamido-2-methylpropane sulfonic acid monomer
unit, and preferably a water-insoluble component is used 5 weight %
or less based on a total weight of the powder detergent
granules.
[0036] Also, the present invention provides a metal ion binding
composition comprising the above-mentioned copolymer, in particular
a calcium ion binding composition.
[0037] Further, the present invention provides a hard-water
softening composition comprising the above-mentioned copolymer
having the above-mentioned properties.
[0038] And, the powder detergent granules of the present invention
comprise 10 to 70 parts by weight of an alkali builder as a
component that brings about a neutralization reaction with the
acidic water-soluble polymer. In consideration of the objects of
the present inventions, preferably the alkali builder is a
water-soluble alkali builder, and the water-soluble alkali builder
may be sodium carbonate (soda ash), sodium bicarbonate (sodium
hydrogen carbonate), sodium sulfate, sodium hydroxide (caustic
soda), or combinations thereof.
[0039] The meaning, `water-soluble` is herein construed as that a
retention ratio of a water-insoluble material is 0.5 weight % or
less when measured by the following measuring method. The
water-solubility measuring method is described as follows: 3.5 g of
a sample to be evaluated is added into 300 ml beaker and 150 ml of
a distilled water is putted into the beaker. Next, the beaker is
sealed and bathed at 70.degree. C. for 3 hours. Subsequently, the
beaker is agitated in a mechanical agitator for about 1 hour.
Filtration is performed using a filter paper of measured weight,
the remaining material on the filter paper is dried at 100.degree.
C., and weight of the dried material is measured. At this time, a
pore size of the filter paper is 0.45 .mu.m. And, weight of a
water-insoluble component remaining on the filter paper is
calculated as % based on weight of the sample.
[0040] Generally, the alkali builder can prevent an increase of pH
of the powder detergent granules by a proper combination, which
inhibits dye transfer to clothes that may occur during a
high-temperature laundry, and in the present invention, the alkali
builder brings about a neutralization reaction with the acidic
water-soluble polymer as well. In particular, density of the powder
detergent granules may be different depending on content of the
alkali builder, and thus it is possible to control the density of
the powder detergent granules by controlling the content of the
alkali builder properly. That is, pores are created by moisture and
gas such as carbon dioxide that are generated by a neutralization
reaction between the above-mentioned acidic water-soluble polymer
as an acid component and the alkali builder as a base component,
and thus the powder detergent granules may be manufactured with
various densities by controlling the pores.
[0041] In the case that the powder detergent granules use a
combination of materials as the alkali builder, not one kind of
material, as contents of sodium bicarbonate and sodium sulfate
increase, the density of powder detergent granules tends to
increase, and therefore, the content of sodium bicarbonate and
sodium sulfate should be properly controlled. And, kind and content
of the alkali builder are selected in consideration of performance
of the powder detergent granules, for example a protein soil
removing capability (as pH of the powder detergent reduces, the
protein soil removing effect increases) and an inorganic soil
removing capability, and easiness of manufacturing the powder
detergent granules (for example, the sodium carbonate makes it easy
to manufacture the powder detergent granules). In particular, the
sodium bicarbonate serves as a pH control agent to buffer a pH of
water, but has high specific gravity and weak alkali property, and
therefore exhibits lower performance for inducing a neutralization
reaction than other kind of alkali builder.
[0042] And, the powder detergent granules of the present invention
may optionally comprise 1 to 30 parts by weight of an organic acid.
The organic acid supplements the acid strength of the
above-mentioned acidic water-soluble polymer. The organic acid acts
as an acid component in a neutralization reaction to cause pores to
a powder detergent, reduce the density of the powder detergent
granules, and improve the washing capability itself of the powder
detergent granules. The organic acid may be a general solid phase
organic acid or liquid phase organic acid, but preferably the
organic acid is a solid phase organic acid such as a derivative of
a carboxylic acid, for example a citric acid, a succinic acid, a
tartaric acid and a malic acid. The organic acid should be selected
in consideration of easiness of manufacturing low-density powder
detergent granules and product performance such as smell on
use.
[0043] Preferably, the organic acid of the present invention has
0.01 to 2 mm of granule size in consideration of effectiveness of
the above-mentioned neutralization reaction.
[0044] And, the powder detergent granules of the present invention
may further comprise 1 to 30 parts by weight of an anionic
surfactant. The anionic surfactant performs a washing function,
i.e. a unique function of the powder detergent granules, and in the
powder detergent granules of the present invention, the anionic
surfactant acts as an acid component together with the
above-mentioned acidic water-soluble polymer (or the acidic
water-soluble polymer and the organic acid) to cause pores to a
powder detergent, thereby manufacturing the powder detergent
granules.
[0045] The anionic surfactant may be a general anionic surfactant
used in a laundry detergent composition. Specifically, the anionic
surfactant may be lauryl benzene sulfonic acid, alpha-olefin
sulfonate, sodium lauryl sulfate, sodium lauryl ethoxylated
sulfate, or combinations thereof. Preferably, the anionic
surfactant may be lauryl benzene sulfonic acid having good physical
properties and good liability to low density. The content of
anionic surfactant may be controlled within the above-mentioned
range according to a desired density of powder detergent
granules.
[0046] And, the powder detergent granules of the present invention
may further comprise 1 to 30 parts by weight of a nonionic
surfactant. Generally, the nonionic surfactant is liquid, and thus
the whole content of the nonionic surfactant affects the density of
the powder detergent granules. In the case that the content of
nonionic surfactant is high, easiness of manufacturing the powder
detergent granules is lowered, and in the case that the content of
the nonionic surfactant is low, washing performance of the powder
detergent granules is reduced, and thus preferably the content of
the nonionic surfactant is 1 to 30 parts by weight. As the powder
detergent granules of the present invention have a lot of pores,
the powder detergent granules can accommodate a considerable amount
of liquid nonionic surfactant.
[0047] In other words, the powder detergent granules of the present
invention are substantially free of zeolite or silica that absorbs
a liquid component, but are capable of accommodating a considerable
amount of liquid nonionic surfactant. Thus, the present invention
provides powder detergent granules that are substantially free of a
water-insoluble component and comprise a nonionic surfactant of 1
weight % or more, preferably above 5 weight % or more, in a
different way from the conventional powder detergent granules.
[0048] The nonionic surfactant is a general nonionic surfactant
used in a laundry detergent composition, for example
polyoxyethylene alkyl ether, coconut diethanolamide, fatty acid
alkanolamine, amine oxide, alkyl polyglucoside, methyl polyethylene
alkyl ether and sugar ether.
[0049] And, the powder detergent granules of the present invention
may further comprise 0.3 to 10 parts by weight of various additives
within the range of not destroying the objects of the present
invention. The additives may include a protein degrading enzyme
(protease) for removing a protein soil, a lipid degrading enzyme
(lipase) for removing a lipid soil, a carbohydrate degrading enzyme
(amylase) for removing a food soil, a cellulose degrading enzyme
(cellulase) for removing lint of a cotton fabric, a fluorescent dye
such as biphenyl and stilbene species, and a dye transfer inhibitor
for inhibiting a dye of a fabric from transferring to another
fabric or inhibiting the separated soil from redeposition with a
fabric.
[0050] Preferably, the powder detergent granules of the present
invention comprise 0.01 to 1 parts by weight of a protein degrading
enzyme, 0.01 to 1 parts by weight of a lipid degrading enzyme, 0.01
to 1 parts by weight of a carbohydrate degrading enzyme and 0.01 to
1 parts by weight of a cellulose degrading enzyme, 0.1 to 1 parts
by weight of a fluorescent dye, and 0.5 to 5 parts by weight of a
dye transfer inhibitor.
[0051] And, according to the present invention, a method for
manufacturing powder detergent granules that are dried by heat
generated from a neutralization reaction between an acidic
water-soluble polymer and an alkali builder, comprises (S1)
preparing an acidic water-soluble polymer and an alkali builder;
(S2) putting 0.1 to 15 parts by weight of the acidic water-soluble
polymer and 10 to 70 parts by weight of the alkali builder into a
mixer; and (S3) uniformly mixing the components of the step (S2)
put into the mixer.
[0052] According to the present invention, when the acidic
water-soluble polymer and the alkali builder putted into the mixer
are uniformly mixed with the above-mentioned mixture ratio, the
acidic water-soluble polymer and the alkali builder bring about a
neutralization reaction to manufacture powder detergent granules.
The resultant moisture is naturally dried by heat generated in the
neutralization reaction. The above-mentioned anionic surfactant and
nonionic surfactant components may be added according to purpose
and function of the powder detergent granules.
[0053] Therefore, in a different way from a conventional method for
manufacturing powder detergent granules, the method of the present
invention may eliminate the need of a heating step for drying the
powder detergent granules or considerably reduce a heating
procedure, thereby resulting in a simple and economical method, and
the powder detergent granules manufactured by such a method are
substantially free of a water-insoluble component, and thus have
good solubility and washing performance in cold water, leave no
residue in laundry and reduce the likelihood of a caking phenomenon
during manufacture and storage.
[0054] Hereinafter, preferred embodiments are provided to describe
the present invention in detail. It should be understood that the
detailed description and specific examples are given by way of
illustration only, since various changes and modifications within
the spirit and scope of the invention will become apparent to those
skilled in the art from this detailed description.
[0055] Manufacture and Evaluation of Acidic Water-Soluble
Polymer
[0056] An acrylic acid monomer unit and
2-acrylamido-2-methylpropane sulfonic acid monomer unit were mixed
with a weight ratio of 9:1, and polymerized in water using a
persulfate initiator to manufacture a random copolymer. The
manufactured copolymer has a molecular weight of 6,000 to 15,000,
and evaluation of other physical properties is shown in the
following Table 1. The copolymer was used in the following
embodiment.
TABLE-US-00001 TABLE 1 Spec. Test Method Appearance Unit Clear
Allowance Sensory Test Solid content Wt. % 50 .+-.1.0 KSM3704
105.degree. C., 3 hrs pH 1 .+-.0.5 KSM0011 pH meter, an undiluted
solution Viscosity cP 1000 .+-.500 KSM3825 #B Viscometer
(25.degree. C.) RVT (#3/50) Odor Slightly Sensory Test acidic
Manufacture of Examples 1-2 and Comparison Examples 1-2
[0057] The examples and comparison examples were manufactured by
mixing raw materials using a high-speed mixer according to
components and content as represented in the following Table 2.
Specifically, the examples and comparison examples were
manufactured in such a typical method that raw materials other than
additives are mixed to manufacture powder detergent granules and
then additives are added.
TABLE-US-00002 TABLE 2 Comparison Comparison Ingredient (parts by
weight) Example 1 Example 2 example 1 example 2 Nonionic
Polyoxyethylene alkyl 6 5 6 5 surfactant ether Anionic Lauryl
benzene sulfonic 10 15 10 15 surfactant acid Acidic water-
Polyacrylic acid 3 -- -- -- soluble Copolymer of acrylic -- 3 -- --
polymer acid & 2-acrylamido-2- methylpropane sulfonic acid
Alkali builder Sodium carbonate 45 50 40 45 Sodium sulfate 20 15 23
28 Softener Zeolite 4A -- -- 5 15 Additives Fluorescent whitening
0.15 agent Protein degrading 0.2 enzyme Cellulose degrading 0.3
enzyme Carbo hydrate degrading 0.2 enzyme Aromatic 0.2
[0058] In the above Table 2, the fluorescent whitening agent was
Tinopal CBS-X (Ciba Special Chem. FMC.), the protein degrading
enzyme was Savinase 12.0T (Novozymes), the cellulose degrading
enzyme was Carezyme 900T (Novozymes), and the carbohydrate
degrading enzyme was Termamyl 120T (Novozymes).
[0059] Evaluation of Caking Phenomenon
[0060] The influence of the powder detergent granules of the
examples and the comparison examples on a caking phenomenon was
observed with the naked eye and judged according to the following
standard for judgment. The judgment results are shown in the
following Table 3.
[0061] [Standard for Judgment]
[0062] Good: detergent granules are not caked and granule mobility
is good.
[0063] Normal: detergent granules are not caked, but a little
wet.
[0064] Inadequate: detergent granules are a little wet and caked
with small sizes in places.
[0065] Poor: detergent granules are wet and caked.
TABLE-US-00003 TABLE 3 Comparison Comparison Measurement Example 1
Example 2 example 1 example 2 Caking phenomenon Normal Good Poor
Inadequate prevention
[0066] As shown in the above Table 3, there was a remarkable
difference in a caking phenomenon between the examples and the
comparison examples, and the example 2 using a copolymer of acrylic
acid and 2-acrylamido-2-methylpropane sulfonic acid as an acidic
water-soluble polymer had better granule condition than the example
1 using a polyacrylic acid polymer as an acidic water-soluble
polymer. And, both of the examples 1 and 2 did not comprise a
water-insoluble component, zeolite, but had better caking
phenomenon preventing capability than the comparison examples.
According to the results, the powder detergent granules having the
component and content described in the present invention can be
manufactured properly by a neutralization reaction without use of
zeolite.
[0067] Evaluation of Washing Performance
[0068] The washing performance, i.e. a stain removal performance of
the powder detergent granules was evaluated. The washing
performance was evaluated using a washing machine of the same
condition and a general city water. The washing temperature was a
temperature of cold water for the same condition as a common
domestic use. A soiled fabric used for evaluation of washing
performance was a fabric prepared artificially with wet soil
according to Japan laundry science association, and washing
performance was evaluated in a statistical manner by comparing
twenty pieces of soiled fabrics having 5.times.5 cm size. WB
values, i.e. whiteness of the soiled fabrics were measured before
and after laundry using a color difference meter. Each of 30 g
powder detergent granules of the examples and the comparison
examples was put into the washing machine, and the soiled fabric
was attached to a real cotton shirt. The washing machine was
operated in a standard course to wash and spin dry the soiled
fabrics, the soiled fabrics were dried in a thermo-hygrostat
(25.degree. C. 20% RH) for one day and ironed, and WB values were
measured using the same color difference meter. The WB values were
substituted for Kubelka-Munk equation represented by the following
Equation 1 to calculate the washing performance, and the
calculation results are shown in the following Table 4.
WashingCapability ( % ) = [ ( 1 - R S 2 ) / 2 R S - ( 1 - R C 2 ) /
2 R C ] [ ( 1 - R S 2 ) / 2 R S - ( 1 - R 0 2 ) / 2 R 0 ] .times.
100 [ Math Figure 1 ] ##EQU00001##
[0069] where Rs is a surface reflection ratio of the soiled fabric,
Rc is a surface reflection ratio of the cotton fabric after stain
removal, and Ro is a surface reflection ratio of a white cotton
fabric.
TABLE-US-00004 TABLE 4 Comparison Comparison Classification Example
1 Example 2 example 1 example 2 Washing 66.87 68.23 63.21 64.84
performance (%) (Japan laundry science association soiled
fabric)
[0070] As shown in the Table 4, as compared with the powder
detergent granules of the comparison examples 1 and 2, the powder
detergent granules of the examples 1 and 2 showed higher washing
performance, and it is judged that improvement of washing
performance was resulted from a soil antiredeposition function and
a water softening effect of the acidic water-soluble polymer. And,
the powder detergent granules of the present invention were free of
a water-insoluble component, and thus the powder detergent granules
were all dissolved and a detergent residue was not left. This leads
to improved washing performance. However, the powder detergent
granules of the comparison examples 1 and 2 were not completely
dissolved, and thus it is judged that the powder detergent granules
of the comparison examples 1 and 2 have lower washing performance
than the powder detergent granules of the examples 1 and 2.
INDUSTRIAL APPLICABILITY
[0071] As such, the powder detergent granules according to the
present invention have good caking phenomenon preventing and
washing performances, and are substantially free of a
water-insoluble component, and thus have good solubility and do not
leave residue in laundry. And, the powder detergent granules of the
present invention are substantially free of zeolite or silica that
absorbs a liquid component, but are capable of accommodating a
considerable amount of liquid surfactant. The acidic water-soluble
polymer of the present invention is useful as a detergent component
in various aspects.
* * * * *