Title: Polymers and their use
Abstract: A substituted polysaccharide comprising β1-4 linkages having covalently bonded on the polysaccharide moiety thereof, at least one deposition enhancing group which undergoes a chemical change in water at a use temperature to increase the affinity of the substituted polysaccharide to a substrate, the substituted polysaccharide further comprising one or more independently selected silicone chains.
Patent Number: 6,903,208 Issued on 06/07/2005 to Findlay, et al.
| Inventors:
|
Findlay; Paul Hugh (Wirral, GB);
Jones; Christopher Clarkson (Wirral, GB);
Kukulj; Dax (Kingston, AU)
|
| Assignee:
|
Unilever Home & Personal Care USA Division of Conopco, Inc. (Greenwich, CT)
|
| Appl. No.:
|
225863 |
| Filed:
|
August 22, 2002 |
Foreign Application Priority Data
| Current U.S. Class: |
536/55.1; 510/470; 510/471; 510/473; 510/515; 536/53; 536/116; 536/120 |
| Intern'l Class: |
C08B 037/00; C11D003/00 |
| Field of Search: |
536/53,116,120,551,56,123.1
510/515,470,471,473
|
References Cited [Referenced By]
U.S. Patent Documents
| 4454295 | Jun., 1984 | Wittmann et al.
| |
| 5082914 | Jan., 1992 | Cook et al.
| |
| 5730760 | Mar., 1998 | Kirk et al.
| |
| 6066727 | May., 2000 | Yamamoto et al.
| |
| Foreign Patent Documents |
| 0366237 | Aug., 1989 | EP.
| |
| 0 459 821 | May., 1991 | EP.
| |
| 1095959 | Oct., 2000 | EP.
| |
| 671721 | May., 1952 | GB.
| |
| 1031484 | Jun., 1966 | GB.
| |
| 1 549 180 | Jul., 1979 | GB.
| |
| 09136901 | May., 1997 | JP.
| |
| 92/13114 | Aug., 1992 | WO.
| |
| 95/35087 | Dec., 1995 | WO.
| |
| 98/00500 | Jan., 1998 | WO.
| |
| 98/29528 | Jul., 1998 | WO.
| |
| 99/14245 | Mar., 1999 | WO.
| |
| 99/14295 | Mar., 1999 | WO.
| |
| 99/21892 | May., 1999 | WO.
| |
| WO 00/1886/1 | Apr., 2000 | WO.
| |
Other References
International Search Report PCT/EP 02 09227 mailed Dec. 16, 2002, 3 pp. Patent
Abstracts of Japan, vol. 1997, No. 9 (May 27, 1997) Abstract of JP 09136901—1 p.
UK Search Report GB 0121148.1 mailed Mar. 8, 2002, 2 pp.
Chem. Abstracts 133:239476 & JP 2000256613 (Shin-Etsu Chemical Industry Co.).
Abstracts of JP 6248002 (Natoko Paint KK).
Abstracts of JP 11107191 (Toppan Printing Co.).
Abstracts of JP 09136901 (Shin-Etsu Chemical Co.) (Previously Submitted).
|
Primary Examiner: Wilson; James O.
Assistant Examiner: Krishnan; Ganapathy
Attorney, Agent or Firm: Bornstein; Alan A.
Claims
1. A substituted polysaccharide comprising β
1-4 linkages having
covalently bonded on the polysaccharide moiety thereof, at least one deposition
enhancing group which undergoes a chemical change in water at a use temperature
to increase the affinity of the substituted polysaccharide to a substrate, the
substituted polysaccharide further comprising one or more independently selected
silicone chains;
wherein the silicone chain(s) is or are independently selected from those of
formula:
##STR30##
wherein L is absent or is a linking group and one or two of substituents G
1-G
3
is a methyl group, the remainder being selected from groups of formula
##STR31##
the —Si(CH
3)
2O— groups and the —Si(CH
3O)(G
4)-
groups being arranged in random or block fashion;
wherein n is from 5 to 1000, and m is from 0 to 100,
G
4 is selected from groups of formula:
—(CH
2)
p—CH
3, where p is from 1
to 18
—(CH
2)
q—NH—(CH
2)
r,—NH
2where
q and r are independently from 1 to 3
—(CH
2)
s—NH
2, where s is from 1
to 3
##STR32##
where t is from 1 to 3
—(CH
2)
u—COOH, where u is from 1 to 10,
##STR33##
where v is from 1 to 10, and
—(CH
2CH
2O)
w—(CH
2)
xH,
where w is from 1 to 150, and x is from 0 to 10;
and G
5 is independently selected from hydrogen, groups defined above
for G
4, —OH, —CH
3 and —C(CH
3)
3.
2. The substituted polysaccharide of claim 1, wherein the average degree of substitution
of the silicone chain(s) is from 0.001 to 0.5.
3. The substituted polysaccharide of claim 1 wherein the substituted polysaccharide
comprises only β
1-4 linkages.
4. The substituted polysaccharide of claim 1 wherein the substituted polysaccharide
comprises additional linkages.
5. The substituted polysaccharide of claim 4 wherein the substituted polysaccharide
comprises β
1-4 and β
1-3 linkages.
6. The substituted polysaccharide of claim 5 wherein the weight ratio of β
1-3
and β
1-4 linkages is from 1:100 to 1:2.
7. The substituted polysaccharide of claim 1, where L is selected from the group
consisting of amide linkages, ester linkages, ether linkages, urethane linkages,
triazine linkages, carbonate linkages, amine linkages and ester-alkylene linkages.
8. The substituted polysaccharide of claim 1, wherein the chemical change is
hydrolysis, perhydrolysis or bond-cleavage.
9. The substituted polysaccharide of claim 1, wherein the group(s) which undergo
the chemical change comprise one or more groups attached via an ester linkage to
the polysaccharide.
10. The substituted polysaccharide of claim 1, having the general formula (1):
##STR34##
wherein at least one or more —OR groups of the polymer are independently
substituted or replaced by silicone chains and at least one or more R groups are
independently selected from groups of formulae:
##STR35##
wherein each R
1 is independently selected from C
1-20 alkyl,
C
2-20 alkenyl and C
5-7 aryl any of which is optionally substituted
by one or more substituents independently selected from C
1-4 alkyl,
C
1-12 alkoxy, hydroxyl, vinyl and phenyl groups;
each R
2 is independently selected from hydrogen and groups R
1
as hereinbefore defined;
R
3 is a bond or is selected from C
1-4 alkylene, C
2-4
alkenylene and C
5-7 arylene groups, the carbon atoms in any of
these being optionally substituted by one or more substituents independently selected
from C
1-12 alkoxy, vinyl, hydroxyl, halo and amine groups;
each R
4 is independently selected from hydrogen, counter cations,
and groups R
1 as hereinbefore defined;
groups R which together with the oxygen atom forming the linkage to the respective
saccharide ring forms an ester or hemi-ester group of a tricarboxylic- or higher
polycarboxylic- or other complex acid selected from the group consisting of citric
acid, an amino acid, or a combination thereof;
and n is the number of repeat units in the polysaccharide and is selected so
that the number average molecular weight of the polysaccharide is in the range
of 1,000 to 200,000.
11. The substituted polysaccharide of claim 9 wherein the ester-linked group(s)
is/are selected from carboxylic acid esters.
12. The substituted polyssaccharide of claims
9, wherein the ester-linked
group(s) is/are independently selected from one or more of acetate, propanoate,
trifluroacetate, 2-(2-hydroxy-1-oxopropoxy) propanoate, lactate, glycolate, pyruvate,
crotonate, isovalerate, cinnamate, formate, salicylate, carbamate, methylcarbamate,
benzoate, gluconate, methanesulphonate, toluene sulphonate, groups and hemiester
groups of fumaric, malonic, itaconic, oxalic, maleic, succinic, tartaric, aspartic,
glutamic, and malic acids.
13. The substituted polysaccharide of claim 1, wherein the average degree of
substitution on the saccharide rings of the groups which undergo the chemical change
is from 0.1 to 3.
14. A method of depositing a silicone onto a substrate, the method comprising
contacting in an aqueous solution, the substrate and a substituted polysaccharide
comprising β
1-4 linkages having covalently bonded on the polysaccharide
moiety thereof, at least one deposition enhancing group which undergoes a chemical
change in water at a use temperature to increase the affinity of the substituted
polysaccharide to a substrate, the substituted polysaccharide further comprising
one or more independently selected silicone chains; and
wherein the silicone chain(s) is or are independently selected from those of
formula:
##STR36##
wherein L is absent or is a linking group and one or two of substituents G
1-G
3
is a methyl group, the remainder being selected from groups of formula
##STR37##
the —Si(CH
3)
2O— groups and the —Si(CH
3O)(G
4)-
groups being arranged in random or block fashion;
wherein n is from 5 to 1000, and m is from 0 to 100,
G
4 is selected from groups of formula:
—(CH
2)
p—CH
3, where p is from 1
to 18
—(CH
2)
q—NH—(CH
2)
r,—NH
2
where q and r are independently from 1 to 3
—(CH
2)
s—NH
2, where s is from 1
to 3
##STR38##
where t is from 1 to 3
—(CH
2)
u—COOH, where u is from 1 to 10,
##STR39##
where v is from 1 to 10, and
—(CH
2CH
2O)
w—(CH
2)
xH,
where w is from 1 to 150, and x is from 0 to 10;
and G
5 is independently selected from hydrogen, groups defined above
for G
4, —OH, —CH
3 and —C(CH
3)
3.
15. A composition comprising a substituted polysaccharide comprising β
1-4
linkages having covalently bonded on the polysaccharide moiety thereof, at least
one deposition enhancing group which undergoes a chemical change in water at a
use temperature to increase the affinity of the substituted polysaccharide to a
substrate, the substituted polysaccharide further comprising one or more independently
selected silicone chains and at least one further component; and
wherein the silicone chain(s) is or are independently selected from those of
formula:
##STR40##
wherein L is absent or is a linking group and one or two of substituents G
1-G
3
is a methyl group, the remainder being selected from groups of formula
##STR41##
the —Si(CH
3)
2O— groups and the —Si(CH
3O)(G
4)-
groups being arranged in random or block fashion;
wherein n is from 5 to 1000, and m is from 0 to 100,
G
4 is selected from groups of formula:
—(CH
2)
p—CH
3, where p is from 1
to 18
—(CH
2)
q—NH—(CH
2)
r,—NH
2
where q and r are independently from 1 to 3
—(CH
2)
s—NH
2, where s is from 1
to 3
##STR42##
where t is from 1 to 3
—(CH
2)
u—COOH, where u is from 1 to 10,
##STR43##
where v is from 1 to 10, and
—(CH
2 CH
2O)
w—(CH
2)
xH,
where w is from 1 to 150, and x is from 0 to 10;
and G
5 is independently selected from hydrogen, groups defined above
for G
4, —OH, —CH
3 and —C(CH
3)
3.
16. A composition of claim 15, in which the further component comprises a surfactant.
17. The composition of claim 15, comprising from 0.01% to 25%, by weight of the
substituted polysaccharide comprising β
1-4 linkages having covalently
bonded on the polysaccharide moiety thereof, at least one deposition enhancing
group which undergoes a chemical change in water at a use temperature to increase
the affinity of the substituted polysaccharide to a substrate, the substituted
polysaccharide further comprising one or more independently selected silicone chains.
18. A method of enhancing the softening benefit of the composition on a substrate,
the method comprising the application of a substituted polysaccharide comprising
β
1-4 linkages having covalently bonded on the polysaccharide moiety
thereof, at least one deposition enhancing group which undergoes a chemical change
in water at a use temperature to increase the affinity of the substituted polysaccharide
to a substrate, the substituted polysaccharide further comprising one or more independently
selected silicone chains, onto a substrate; and
wherein the silicone chain(s) is or are independently selected from those of
formula:
##STR44##
wherein L is absent or is a linking group and one or two of substituents G
1-G
3
is a methyl group, the remainder being selected from groups of formula
##STR45##
the —Si(CH
3)
2O— groups and the —Si(CH
3O)(G
4)-
groups being arranged in random or block fashion;
wherein n is from 5 to 1000, and m is from 0 to 100,
G
4 is selected from groups of formula:
—(CH
2)
p—CH
3, where p is from 1
to 18
—(CH
2)
q—NH—(CH
2)
r,—NH
2
where q and r are independently from 1 to 3
—(CH
2)
s—NH
2, where s is from 1
to 3
##STR46##
where t is from 1 to 3
—(CH
2)
u—COOH, where u is from 1 to 10,
##STR47##
where v is from 1 to 10, and
—(CH
2 CH
2O)
w—(CH
2)
xH,
where w is from 1 to 150, and x from 0 to 10;
and G
5 is independently selected from hydrogen, groups defined above
for G
4, —OH, —CH
3 and —C(CH
3)
3.
19. The substituted polysaccharide of claim 1 where w is from 10 to 20.
20. The method of claim 14 where w is from 10 to 20.
21. The method of claim 15 where w is from 10 to 20.
22. The method of claim 18 where w is from 10 to 20.
Description
TECHNICAL FIELD
The present invention relates to a substituted polysaccharide of the kind comprising
a benefit agent and a deposition aid for deposition of the benefit agent onto a
substrate. It further relates to a method of depositing a benefit agent from solution
or dispersion, onto a substrate.
BACKGROUND OF THE INVENTION
The deposition of a benefit agent onto a substrate, such as a fabric, is well
known in the art. In laundry applications typical "benefit agents" include fabric
softeners and conditioners, soil release polymers, sunscreens; and the like. Deposition
of a benefit agent is used, for example, in fabric treatment processes such as
fabric softening to impart desirable properties to the fabric substrate.
Conventionally, the deposition of the benefit agent has had to rely
upon the attractive forces between the oppositely charged substrate and the benefit
agent. Typically this requires the addition of benefit agents during the rinsing
step of a treatment process so as to avoid adverse effects from other charged chemical
species present in the treatment compositions. For example, cationic fabric conditioners
are incompatible with anionic surfactants in laundry washing compositions.
Such adverse charge considerations can place severe limitations upon the inclusion
of benefit agents in compositions where an active component thereof is of an opposite
charge to that of the benefit agent. For example, cotton is negatively charged
and thus requires a positively charged benefit agent in order for the benefit agent
to be substantive to the cotton, i.e. to have an affinity for the cotton so as
to absorb onto it.
Often the substantivity of the benefit agent is reduced and/or the deposition
rate of the material is reduced because of the presence of incompatible charged
species in the compositions. However, in recent times, it has been proposed to
deliver a benefit agent in a form whereby it is substituted onto another chemical
moiety which increases its affinity for the substrate in question.
PRIOR ART
WO-A-98/00500 discloses detergent compositions comprising a peptide
or protein deposition aid having a high affinity for fibres or a surface, and a
benefit agent attached/adsorbed to the deposition aid. However, this deposition
aid does not change chemically such as to increase its affinity for the substrate
during the treatment process.
GB-A-1 031 484 discloses stable aqueous dispersions of elastic copolymers
which can be converted to cross-linked polymers by the action of heat or acid.
They can be used to produce films or covering layers. However, none of the compounds
has a benefit agent attached to the deposition enhancing part. There is no disclosure
of using these materials in methods of laundry or fabric care.
U.S. Pat. No. 5,730,760 discloses a process of fabric washing in which a dye
redeposition inhibiting agent is used. The dye redeposition inhibiting polymer
used is of a specific type, being produced by polymerising, for example, vinylester
monomers. There is not any mention of materials having any surface substantive
properties nor is there a description of any reaction by which such surface substantive
properties increase during use.
WO-A-92/13114 discloses hair fixative polymers which form a film after
application. The polymers are fundamentally different from those of the present
invention in that they do not comprise a deposition part attached to a benefit
agent. The polymeric material has no particular affinity for hair—it is
just applied onto it. There is certainly no mention of a reaction which increases
the affinity. Any reaction which occurs leads to the cross-linking of polymer and
the formation of film. It is not disclosed that the polymers should be water-soluble
of dispersible—they are normally dissolved in an inert carrier such as alcohol.
WO-A-95/35087 discloses a hair fixative amphoteric polymer composition.
It is insoluble in water but can be solubilised by use of neutralisers or solubilising
alcohol/water mixtures. The polymers do not to undergo any reaction which increases
their affinity for hair. There is no benefit agent attached to the polymer.
WO-A-98/29528 discloses cellulose ethers in which some substituents
are (poly)alkoxylated, analogues of the latter in which the (poly)alkoxylated groups
are terminated with a cationic moiety in the form of a quaternary ammonium group,
and cellulose ethers in which some substituents are carboxylic acids in the salt
form (i.e. the materials are essentially carboxymethylcellulose variants). None
of these substituents in any variant is of a kind which would undergo a chemical
change to enhance fabric affinity.
WO-A-99/14245 discloses laundry detergent compositions containing cellulosic
based polymers to provide appearance and integrity benefits to fabrics. These polymers
are cellulosic polymers in which the saccharide rings have pendant oxygen atoms
to which substituents ‘R’ are bonded, i.e. they are attached to the
rings via an ether linkage. The groups ‘R’ can be hydrogen, lower
alkyl or alkylene linkages terminated by carboxylic acid, ester or amide groups.
Optionally, up to five alkyleneoxy groups may be interspersed between the groups
are the respective oxygen atom. None of the pendant groups is a benefit agent group.
However, at least some of these groups may undergo a chemical change such as hydrolysis,
in the wash liquor. However no such change would result in an increased affinity
for the fabric. On the contrary, because the "ester" group is configured with the
carbonyl group closer to the polysaccharide than the oxygen atom (i.e. esters of
carboxyalkyl groups), any hydrolysis will result in free acid substituents which
will actually result in an increase in solubility and therefore, a decrease in
affinity for the fabric.
WO-A-99/14295 discloses structures analogous to those described in
WO-A-99/14245 but in one alternative, the substituents ‘R’ together
with the oxygen on the saccharide ring, constitute pendant half-esters of certain
dicarboxylic acids. A single example of such a material is given. Again, no pendant
group is a benefit agent group. However, the dicarboxylic acid half-esters would
tend to hydrolyse in the wash liquor and thereby increase affinity of the material
for a cotton fabric. However, first, this mechanism of action or behaviour is not
mentioned. Second, the hydrolysis rate of such dicarboxylic acids half esters is
not as great as that of esters of monocarboxylic acids (which are not disclosed
or claimed in WO-A-99/14295). Third, the degree of substitution for this variant
is specified as being from 0.001 to 0.1. This is so low as to make the enhancement
of fabric affinity too low to be worthwhile for this mechanism of action. Fourth,
the structures described and claimed insofar as they have such half ester substituents,
must also have substituents of the type which are carboxyalkyl groups or esters
thereof, i.e. of the type also described in WO-A-99/14245. In the latter (ester)
case, these would hydrolyse to the free acid form. The degree of substitution of
the latter (0.2 to 2) is considerably higher than for the half-ester groups and
the resultant increase in solubility would easily negate any enhanced affinity
for the fabric by hydrolysis of the half-ester groups.
WO-A-00/18861 provides a water-soluble or water-dispersible material
for deposition onto a substrate during a treatment process, wherein the material comprises:
- (i) a deposition enhancing part having a polymeric backbone; and
- (ii) a benefit agent group attached to the deposition enhancing part
by a hydrolytically stable bond;
such that the material undergoes during the treatment process, a chemical change
which does not involve the hydrolytically stable bond and by which change the affinity
of the material onto the substrate is increased. The preferred materials are substituted polysaccharides.
WO-A-00/18861 mentions as possible benefit groups, lubricants, ironing
aids and fabric softeners. However, it is known that silicone materials are especially
useful agents for delivering this kind of benefit. Up to now, there has been no
specific teaching of how to deliver a silicone to a cotton substrate by use of
a polysaccharide. The present invention is aimed at solving this problem.
DEFINITION OF THE INVENTION
A first aspect of the present invention provides a substituted polysaccharide
comprising
β
1-4 linkages having covalently bonded on the polysaccharide moiety
thereof, at least one deposition enhancing group which undergoes a chemical change
in water at a use temperature to increase the affinity of the substituted polysaccharide
to a substrate, the substituted polysaccharide further comprising one or more independently
selected silicone chains.
A second aspect of the present invention provides a method for depositing a silicone
onto a substrate, the method comprising, contacting in an aqueous medium, the substrate
and a substituted polysaccharide according to the first aspect of the invention.
A third aspect of the present invention also provides compositions comprising
a
material according to the first aspect of the present invention. In particular,
such compositions preferably comprise one or more surfactants and are suitable
for use in washing applications such as laundry.
A further aspect of the invention provides the use of a composition according
to
the third aspect to enhance the softening benefit of the composition on a substrate.
DETAILED DESCRIPTION OF THE INVENTION
The Substituted Polysaccharide
In the substituted polysaccharide, the silicone chain is preferably attached
to
the polysaccharide by a covalent stable bond. That means that the bonding of the
silicone should be sufficiently stable so as not to undergo hydrolysis in the environment
of the treatment process for the duration of that process. For example, in laundry
cleaning applications, the substituted polysaccharide should be sufficiently stable
so that the bond between the silicone and polysaccharide does not undergo hydrolysis
in the wash liquor, at the wash temperature, before the silicone has been deposited
onto the fabric.
Preferably, the bond between the silicone and the polysaccharide is such
that the decay rate constant (k
d) of the material in an aqueous solution
at 0.01 wt % of the material together with 0.1 wt % of anionic surfactant at a
temperature of 40° C. at a pH of 10.5 is such that k
d<10
-3s
-1.
The substituted polysaccharide of the present invention is water-soluble or water-dispersible
in nature and comprises a polysaccharide substituted with at least one silicone
attached to the polysaccharide aid by a hydrolytically stable bond.
By water-soluble, as used herein, what is meant is that the material forms an
isotropic solution on addition to water or another aqueous solution.
By water-dispersible, as used herein, what is meant is that the material forms
a finely divided suspension on addition to water or another aqueous solution.
By an increase in the affinity of the substituted polysaccharide for a substrate
such as a textile fabric upon a chemical change, what is meant is that at some
time during the treatment process, the amount of material that has been deposited
is greater when the chemical change is occurring or has occurred, compared to when
the chemical change has not occurred and is not occurring, or is occurring more
slowly, the comparison being made with all conditions being equal except for that
change in the conditions which is necessary to affect the rate of chemical change.
Deposition onto a substrate includes deposition by adsorption, co-crystallisation,
entrapment and/or adhesion.
The Polysaccharide Part
The polysaccharide is preferably β
1-4 linked and is a cellulose,
a cellulose derivative, or another β-
1,4-linked polysaccharide
having an affinity for cellulose, such as mannan and glucomannan.
Preferably, the polysaccharide has only β-
1,4 linkages.
Optionally, the polysaccharide has linkages in addition to the β-
1,4
linkages, such as β-
1,3 linkages. Thus, optionally some
other linkages are present. Polysaccharide backbones which include some material
which is not a saccharide ring are also within the ambit of the present invention
(whether terminal or within the polysaccharide chain).
The polysaccharide may be straight or branched. Many naturally occurring polysaccharides
have at least some degree of branching, or at any rate at least some saccharide
rings are in the form of pendant side groups (which are therefore not in themselves
counted in determining the degree of substitution) on a main polysaccharide backbone.
A polysaccharide comprises a plurality of saccharide rings which have pendant
hydroxyl
groups. In the substituted polysaccharides of the present invention, at least some
of these hydroxyl groups are independently substituted by, or replaced with, one
or more other substituents, at least one being a silicone chain. The "average degree
of substitution" for a given class of substituent means the average number of substituents
of that class per saccharide ring for the totality of polysaccharide molecules
in the sample and is determined for all saccharide rings.
The Deposition Enhancing Group
A deposition enhancing group is a group which undergoes a chemical change in
use,
and is attached to the polysaccharide agent group by means of a covalent stable
bond. This chemical change results in an increase of the affinity of the material
for the substrate and is referred to further below.
The chemical change which causes the increased substrate affinity is preferably
caused by hydrolysis, perhydrolysis or bond-cleavage, optionally catalysed by an
enzyme or another catalyst. Hydrolysis of substituent ester-linked groups is typical.
By ester linkage is meant that the hydrogen of an —OH group has been replaced
by a substituent such as R′—CO—, R′SO
2—
etc to form a carboxylic acid ester, sulphonic acid ester (as appropriate) etc
together with the remnant oxygen attached to the saccharide ring. In some cases,
the group R′ may for example contain a heteroatom, e.g. as an —NH—
group attached to the carbonyl, sulphonyl etc group, so that the linkage as a whole
could be regarded as a urethane etc linkage. However, the term ester linkage is
still to be construed as encompassing these structures.
The average degree of substitution of these pendant groups which undergo the
chemical change is preferably from 0.1 to 3 (e.g. from 0.3 to 3), more preferably
from 0.1 to 1 (e.g. from 0.3 to 1).
The Silicone Chain(s)
As used herein the term "silicone chain" means a polysiloxane or derivative thereof.
In the section "Preferred Overall Structure" hereinbelow, various preferred silicone
chains are recited and these are typically suitable, whether or not the substituted
polysaccharide conforms to the preferred overall structure.
Preferred Overall Structures
Preferred substituted polysaccharides of the invention are cellulosic polymers
of formula (I):
##STR1##
(optional β-
1,3 and/or other linkages and/or other groups
being permitted in the above formula (I))wherein at least one or more —OR
groups of the polymer are substituted by or replaced by independently selected
silicone chains and at least one or more R groups are independently selected from
groups of formula:
##STR2##
wherein each R
1 is independently selected from C
1-20
(preferably C
1-6) alkyl, C
2-20 (preferably C
2-6)
alkenyl (e.g. vinyl) and C
5-7 aryl (e.g. phenyl) any of which is optionally
substituted by one or more substituents independently selected from C
1-4 alkyl,
C
1-12 (preferably C
1-4) alkoxy, hydroxyl, vinyl and phenyl groups;
each R2 is independently selected from hydrogen and groups R1
as hereinbefore defined;
R3 is a bond or is selected from C1-4 alkylene, C2-4
alkenylene and C5-7 arylene (e.g. phenylene) groups, the carbon
atoms in any of these being optionally substituted by one or more substituents
independently selected from C1-12 (preferably C1-4) alkoxy,
vinyl, hydroxyl, halo and amine groups;
each R4 is independently selected from hydrogen, counter cations
such as alkali metal (preferably Na) or ½ Ca or ½ Mg, and groups R1
as hereinbefore defined; and
groups R which together with the oxygen atom forming the linkage to the
respective saccharide ring forms an ester or hemi-ester group of a tricarboxylic-
or higher polycarboxylic- or other complex acid such as citric acid, an amino acid,
a synthetic amino acid analogue or a protein;
any remaining R groups being selected from hydrogen and other substituents.
For the avoidance of doubt, as already mentioned, formula (I), some of the R
groups may optionally have one or more structures, for example as hereinbefore
described. For example, one or more R groups may simply be hydrogen or an alkyl group.
Preferred groups which undergo the chemical change may for example be independently
selected from one or more of acetate, propanoate, trifluroacetate, 2-(2-hydroxy-1-oxopropoxy)
propanoate, lactate, glycolate, pyruvate, crotonate, isovalerate cinnamate, formate,
salicylate, carbamate, methylcarbamate, benzoate, gluconate, methanesulphonate,
toluene, sulphonate, groups and hemiester groups of fumaric, malonic, itaconic,
oxalic, maleic, succinic, tartaric, aspartic, glutamic, and malic acids.
Particularly preferred such groups are the monoacetate, hemisuccinate,
and 2-(2-hydroxy-1-oxopropoxy)propanoate. The term "monoacetate" is used herein
to denote those acetates with the degree of substitution of 1 or less on a cellulose
or other β-1,4 polysaccharide backbone.
Cellulose esters of hydroxyacids can be obtained using the acid anhydride
in acetic acid solution at 20-30° C. and in any case below 50° C. When
the product has dissolved the liquid is poured into water (b.p. 316, 160). Tri-esters
can be converted to secondary products as with the triacetate. Glycollic and lactic
ester are most common.
Cellulose glycollate may also be obtained from cellulose chloracetate (GB-A-320
842) by treating 100 parts with 32 parts of NaOH in alcohol added in small portions.
An alternative method of preparing cellulose esters consists in the partial displacement
of the acid radical in a cellulose ester by treatment with another acid of higher
ionisation constant (FR-A-702 116). The ester is heated at about 100° C. with
the acid which, preferably, should be a solvent for the ester. By this means cellulose
acetate-oxalate, tartrate, maleate, pyruvate, salicylate and phenylglycollate have
been obtained, and from cellulose tribenzoate a cellulose benzoate-pyruvate. A
cellulose acetate-lactate or acetate-glycollate could be made in this way also.
As an example cellulose acetate (10 g.) in dioxan (75 ml.) containing oxalic acid
(10 g.) is heated at 100° C. for 2 hours under reflux.
Multiple esters are prepared by variations of this process. A simple ester
of cellulose, e.g. the acetate, is dissolved in a mixture of two (or three) organic
acids, each of which has an ionisation constant greater than that of acetic acid
(1.82×10
-5): With solid acids suitable solvents such as propionic
acid, dioxan and ethylene dichloride are used. If a mixed cellulose ester is treated
with an acid this should have an ionisation constant greater than that of either
of the acids already in combination.
A cellulose acetate-lactate-pyruvate is prepared from cellulose acetate, 40 per
cent. acetyl (100 g.), in a bath of 125 ml. pyruvic acid and 125 ml. of 85 per
cent. lactic acid by heating at 100° C. for 18 hours. The product is soluble
in water and is precipitated and washed with ether-acetone. M.p. 230-250° C.
In the case of those materials having a cellulose backbone and pendant ester
groups,
without being bound by any particular theory or explanation, the inventors have
conjectured that the mechanism of deposition is as follows.
Cellulose is substantially insoluble in water. Attachment of the ester
groups to make a cellulose derivative causes disruption of the hydrogen bonding
between rings of the cellulose chain or chains, thus increasing water solubility
or dispersibility. In the treatment liquor, the ester groups are hydrolysed, causing
the cellulose derivative to increase its affinity for the substrate, e.g. the fabric.
In the case when solubilising groups are attached to the polysaccharide, this
is typically via covalent bonding and, may be pendant upon the backbone or incorporated
therein. The type of solubilising group may alter according to where the group
is positioned with respect to the backbone.
In this specification the "n" subscript used in the general formulae of the substituted
polysaccharide is a generic reference to a polymer. Although "n" can also mean
the actual (average) number of repeat units present in the polysaccharide, it is
more meaningful to refer to "n" by the number average molecular weight.
The number average molecular weight (M
n) of the substituted polysaccharide
part may typically be in the range of 1,000 to 200,000, for example 2,000 to 100,000,
e.g. as measured using GPC with multiple angle laser scattering detection.
The silicone chains preferred for use to substitute or replace (dependent upon
the synthetic route use to prepare the substituted polysaccharides of the invention)
at least one —OR group in the compounds of formula (I) are representative
of preferred silicone chains for use in substituted polysaccharides used in the
invention as a whole, ie whether or not the overall structure conforms to Formula (I).
Preferably, the average degree of substitution for the silicone chains
is from 0.001 to 0.5, preferably 0.01 to 0.5, more preferably from 0.01 to 0.1,
still more preferably from 0.01 to 0.05.
Even more preferably the average degree of substitution for the silicone chains
is from 0.00001 to 0.1, more preferably from 0.001 to 0.04, even more preferably
from 0.001 to 0.01.
Preferred silicone chains suitable for this use are those of formula:
##STR3##
wherein L is absent or is a linking group and one or two of substituents
G
1-G
3 is a methyl group, the remainder being selected from
groups of formula
##STR4##
the —Si(CH
3)
2O— groups and the —Si(CH
3O)(G
4)—
groups being arranged in random or block fashion, but preferably random.
wherein n is from 5 to 1000, preferably from 10 to 200 and m is from 0 to
100, preferably from 0 to 20, for example from 1 to 20.
G
4 is selected from groups of formula:
—(CH2)p—CH3, where p is from
1 to 18
—(CH2)q—NH—(CH2)r,
—NH2 where q and r are independently from 1 to 3
—(CH2)s—NH2, where s is from
1 to 3
##STR5##
where t is from 1 to 3
—(CH2)u—COOH, where u is from 1 to 10,
##STR6##
where v is from 1 to 10, and
—(CH2CH2O)w—(CH2)xH,
where w is from 1 to 150, preferably from 10 to 20 and x is from 0 to 10;
and G5 is independently selected from hydrogen, groups defined
above for G4, —OH, —CH3 and —C(CH3)3.
Other Substituents
As well as the silicone chain(s) and the pendant group(s) which undergo a chemical
change to enhance deposition, pendant groups of other types may optionally be present,
i.e. groups which do not confer a benefit and which do not undergo a chemical change
to enhance substrate affinity. Within that class of other groups is the sub-class
of groups for enhancing the solubility of the material (e.g. groups which are,
or contain one or more free carboxylic acid/salt and/or sulphonic acid/salt and/or
sulphate groups).
Examples of solubility enhancing substituents include carboxyl, sulphonyl,
hydroxyl, (poly)ethyleneoxy- and/or (poly)propyleneoxy-containing groups, as well
as amine groups.
The other pendant groups preferably comprise from 0% to 65%, more preferably
from 0% to 10% of the total number of pendant groups. The water-solubilising groups
could comprise from 0% to 100% of those other groups but preferably from 0% to
20%, more preferably from 0% to 10%, still more preferably from 0% to 5% of the
total number of other pendant groups.
Synthetic Routes
As described above, preferred substituted polysaccharides of the present invention
are those of formula (I). Further, preferred silicone chains, whether for the compounds
of formula (I) or any other substituted polysaccharides of the invention are preferably
attached via a linking group "-L-". This linking group is the residue of the reactants-used
to form the substituted polysaccharide.
The substituted polysaccharides of the invention can be made thus:
(a) a polysaccharide is first substituted with one or more deposition enhancing
groups; and
(b) one or more silicone groups are then attached.
If any other substituents are to be present, these may already be present in
the
commercially available polysaccharide, or attached before or after step (a) and/or (b).
Whilst steps (a) and (b) can be reversed, the reaction whereby step (a) is
conducted first is preferred.
The deposition enhancing group(s) is/or are attached in step (a) according to
the methodology described in WO-A-00/18861.
In step (b), one or more hydroxyl groups on the polysaccharide are reacted with
a reactive group attached to the silicone chain, or the hydroxyl group(s) in question
is/are converted to another group capable of reaction with a reactive group attached
to the silicone chain. Listed below, are suitable mutually reactive groups. In
the case of hydroxyl groups, these may be the original hydroxyl group of the polysaccharide.
However, either of a pair of these mutually reactive groups may be present on the
polysaccharide and the other attached to the silicone chain, or vice versa, the
reaction chemistry being chosen appropriately. In the following description, for
convenience, "PSC" refers to the polysaccharide chain with or without deposition
enhancing group(s) and/or other substituent(s) already attached. "SXC" refers to
the group
##STR7##
as hereinbefore defined.
Preferred linking groups -L- are selected from the following, wherein preferably,
the left hand end of the group depicted is connected to the saccharide ring either
direct or via the residual oxygen of one of the original saccharide —OH
groups and the right hand end is connected to the moiety —Si(G
1G
2G
3).
Thus, the configuration as written is PSC-L-SXC. However, the reverse configuration
SXC-L-PSC is also within the ambit of this definition and this is also mentioned
where appropriate.
Preferred linking groups -L- are selected from amide, ester, ether, urethane,
triazine, carbonate, amine and ester-alkylene linkages.
A preferred amide linkage is:
##STR8##
where G
6 and G
7 are each optionally present and are independently
selected spacer groups, e.g. selected from C
1-14 alkylene groups, arylene,
C
1-4 alkoxylene, a residue of an oligo- or poly-ethylene oxide moiety,
C
1-4 alkylamine or a polyamine groups and
G
8 is hydrogen or C
1-4 alkyl.
This linkage can be formed by reacting
##STR9##
wherein G
7 and G
8 are as hereinbefore defined and G
9
is hydrogen or C
1-4 alkyl; with a compound of formula:
##STR10##
wherein G
11 is hydroxy, a group with active ester functionality
halo, or a leaving group suitable for neucleophilie displacement such as imidazole
or an imidazole-containing group and wherein G
6 is hereinbefore defined
above, or —CO-G
11 is replaced by a cyclic acid anhydride. Active
ester synthesis is described in M. Bodanszky, "The Peptides", Vol. 1, Academic
Press Inc., 1975, pp105 ff.
The reverse configuration linkage may be formed by reacting
##STR11##
wherein G
12 is a ring-opened carboxylic acid anhydride, phenylene,
or a group of formula
##STR12##
and G
11 is as hereinbefore defined;
with the group of formula
##STR13##
where G
6 and G
8 are as hereinbefore defined.
A preferred ester linkage has the formula
##STR14##
wherein G
6 and G
7 are as hereinbefore defined, G
8
optionally being absent.
This may be formed by reacting
##STR15##
wherein G
11 and G
12 are as hereinbefore defined with
wherein G
6 is as hereinbefore defined.
The reverse ester linkage formation may be formed by reacting
(i.e. the optionally modified polysacharide with at least one residual —OH
group) with
##STR16##
wherein G
6 and G
11 are as hereinbefore defined, or
—CO-G
11 may be replaced by a cyclic anhydride.
Preferred ether linkages have the formula
wherein G
6 and G
7 are as hereinbefore defined, optionally
one being absent.
This linkage may be formed by reacting
with
##STR17##
wherein G
15 is C
1-4 alkylene and G
6 is optionally
absent and is as hereinbefore defined.
A preferred urethane linkage is
##STR18##
wherein G
6 and G
7 are as hereinbefore defined, G
6
optionally being absent (preferably absent in the configuration PSC-L-SXC)
with
wherein G
6 and G
7 are as hereinbefore defined, G
6
optionally being absent (preferably absent in the configuration PSC-L-SXC)
The reverse configuration is also possible but the simplest arrangement is PSC-L-SXC
and wherein G
6 is absent. Also most common is when G
7 is alkylene.
The latter compound is made by reacting
wherein G
7 is as hereinbefore defined;
with phosgene.
Another route is to react
wherein G
6 is as hereinbefore defined
with carbonyl dimidazole to form
##STR19##
and react that product with
wherein G
7 is as hereinbefore defined.
Preferred triazine linkages have the formula
##STR20##
wherein G
6 and G
7 are as hereinbefore defined, G
6
optionally being absent.
These linkages may be formed by reacting
wherein G
7 is as hereinbefore defined with cyanuic chloride and
then with
wherein G
6 is as hereinbefore defined but may be absent;
or (reverse -L-) by reacting
with cyanuric chloride (when G
7 is as hereinbefore defined) and then with
Preferred carbonate linkages have the formula
##STR21##
wherein G
6 is as hereinbefore defined.
This linkage may be formed by reacting
with
in the presence of carbonyl dimidazole or phosgene
Preferred amine linkages have the formula
##STR22##
wherein G
6, G
7, G
8, G
9 and G
15
are as hereinbefore defined.
This linkage may be formed by reacting
##STR23##
wherein G
6-G
9 are hereinbefore defined;
with
##STR24##
wherein G
15 is as hereinbefore defined.
Preferred ester-alkylene linkages have the formula
##STR25##
wherein G
7 is as hereinbefore defined.
These linkages may be prepared by reacting
with
##STR26##
and then reacting with a hydrogen-terminated silicone chain compound (i.e. G
5=H)
over a platinum catalyst.
Compositions
The substituted polysaccharide according to the first aspect of the present invention
may be incorporated into compositions containing only a diluent (which may comprise
solid and/or liquid) and/or also comprising an active ingredient. The compound
is typically included in said compositions at levels of from 0.01% to 25% by weight,
preferably from 0.1% to 10%, most preferably from 0.5% to 3%.
The active ingredient in the compositions is preferably a surface active agent
or a fabric conditioning agent. More than one active ingredient may be included.
For some applications a mixture of active ingredients may be used.
The compositions of the invention may be in any physical form e.g. a solid such
as a powder or granules, a tablet, a solid bar, a paste, gel or liquid, especially,
an aqueous based liquid. In particular the compositions may be used in laundry
compositions, especially in liquid, powder or tablet laundry composition. The compositions
of the present invention are preferably laundry compositions, especially main wash
(fabric washing) compositions or rinse-added softening compositions. The main wash
compositions may include a fabric softening agent and rinse-added fabric softening
compositions may include surface-active compounds, particularly non-ionic surface-active
compounds, if appropriate.
The detergent compositions of the invention may contain a surface-active compound
(surfactant) which may be chosen from soap and non-soap anionic, cationic, non-ionic,
amphoteric and zwitterionic surface-active compounds and mixtures thereof. Many
suitable surface-active compounds are available and are fully described in the
literature, for example, in "Surface-Active Agents and Detergents", Volumes I and
II, by Schwartz, Perry and Berch.
The preferred detergent-active compounds that can be used are soaps and synthetic
non-soap anionic and non-ionic compounds.
The compositions of the invention may contain linear alkylbenzene sulphonate,
particularly linear alkylbenzene sulphonates having an alkyl chain length of C
8-C
15.
It is preferred if the level of linear alkylbenzene sulphonate is from 0 wt % to
30 wt %, more preferably 1 wt % to 25 wt %, most preferably from 2 wt % to 15 wt %.
The compositions of the invention may contain other anionic surfactants in amounts
additional to the percentages quoted above. Suitable anionic surfactants are well-known
to those skilled in the art. Examples include primary and secondary alkyl sulphates,
particularly C
8-C
15 primary alkyl sulphates; alkyl ether
sulphates; olefin sulphonates; alkyl xylene sulphonates; dialkyl sulphosuccinates;
and fatty acid ester sulphonates. Sodium salts are generally preferred.
The compositions of the invention may also contain non-ionic surfactant. Nonionic
surfactants that may be used include the primary and secondary alcohol ethoxylates,
especially the C
8-C
20 aliphatic alcohols ethoxylated with
an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more
especially the C
10-C
15 primary and secondary aliphatic alcohols
ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of
alcohol. Non-ethoxylated nonionic surfactants include alkylpolyglycosides, glycerol
monoethers, and polyhydroxyamides (glucamide).
It is preferred if the level of non-ionic surfactant is from 0 wt % to 30 wt
%,
preferably from 1 wt % to 25 wt %, most preferably from 2 wt % to 15 wt %.
Any conventional fabric conditioning agent may be used in the compositions of
the present invention. The conditioning agents may be cationic or non-ionic. If
the fabric conditioning compound is to be employed in a main wash detergent composition
the compound will typically be non-ionic. For use in the rinse phase, typically
they will be cationic. They may for example be used in amounts from 0.5% to 35%,
preferably from 1% to 30% more preferably from 3% to 25% by weight of the composition.
Suitable cationic fabric softening compounds are substantially water-insoluble
quaternary ammonium materials comprising a single alkyl or alkenyl long chain having
an average chain length greater than or equal to C
20 or, more preferably,
compounds comprising a polar head group and two alkyl or alkenyl chains having
an average chain length greater than or equal to C
14. Preferably the
fabric softening compounds have two long chain alkyl or alkenyl chains each having
an average chain length greater than or equal to C
16. Most preferably
at least 50% of the long chain alkyl or alkenyl groups have a chain length of C
18
or above. It is preferred if the long chain alkyl or alkenyl groups of the
fabric softening compound are predominantly linear.
Quaternary ammonium compounds having two long-chain aliphatic groups,
for example, distearyidimethyl ammonium chloride and di(hardened tallow alkyl)
dimethyl ammonium chloride, are widely used in commercially available rinse conditioner
compositions. Other examples of these cationic compounds are to be found in "Surfactants
Science Series" volume 34 ed. Richmond 1990, volume 37 ed. Rubingh 1991 and volume
53 eds. Cross and Singer 1994, Marcel Dekker Inc. New York".
Any of the conventional types of such compounds may be used in the compositions
of the present invention.
The fabric softening compounds are preferably compounds that provide excellent
softening, and are characterised by a chain melting L
β to L
α
transition temperature greater than 25° C., preferably greater than 35°
C., most preferably greater than 45° C. This L
β to L
α
transition can be measured by differential scanning calorimetry as defined in "Handbook
of Lipid Bilayers", D Marsh, CRC Press, Boca Raton, Fla., 1990 (pages 137 and 337).
