Note: Descriptions are shown in the official language in which they were submitted.
WO 95/07342 PCT/US94/09939
217i287
DRYER-ACTIVATED`FABRIC CONDITIONING ARTICLES
WITH SOFT POLYESTER S,UBSTRATE
TECHNICAL FIELD
10The present invention relates to an improvement in dryer
activated, e.g., dryer-added, softening products. These products
are prepared by attaching compositions to a substrate.
SUMMARY OF THE INVENTION
The present invention relates to dryer-activated fabric
softening articles comprising improved polyester substrates for
use in an automatic clothes dryer. These articles comprise:
(A) at least about 5%, preferably from about 10Y. to about
90%, more preferably from about lOYo to about 75%, and
even more preferably from about 15% to about 55%, of
fabric conditioning composition comprising fabric
conditioning active and
(B) a polyester non-woven fabric substrate prepared from a
polyester fiber having a denier of from about 2 to about
6, said substrate having a basis weight of from about
0.52 oz/yd2 to about 0.58 oz/yd2, preferably from about
0.53 oz/yd2 to about 0.57 oz/yd2, more preferably from
about 0.54 oz/yd2 to about 0.56 oz/yd2, and a thickness
of from about 0.16 mm to about 0.22 mm, preferably from
about 0.17 mm to about 0.21 mm, more preferably from
about 0.18 mm to about 0.20 mm, and, preferably, a tear
strength of at least about 3 lbs/in2 in both the cross
direction and the machine direction, preferably from
about 4 to about 7 lbs/in2 in the cross direction and
from about 3.1 to about 6 lbs/in2 in the machine direc-
tion, said polyester having improved feel character-
istics as compared to conventional substrates of this
WO 95/07342 , PCT/IJS94/09939
~ ~ 712 8 7
- 2 -
type, after said article is used in said automatic
clothes dryer and after said fabric conditioning com-
position has been substantially completely removed from
said substrate.
The amount of (A) present is at least sufficient to provide
improved fabric characteristics.
DETAILED DESCR~PTION OF THE INVENTION
The present invention relates to dryer-added fabric softening
articles comprising substrates with improved feel after use, for
use in an automatic clothes dryer. It has surprisingly been found
that consumers who have used dryer-added fabric softener articles
prepared with rayon non-woven substrates find that similar
articles prepared with spun-bonded polyester substrates are not as
soft after use, when the substrate is removed from the clothes.
The improved articles herein comprise:
(A) at least about 5Y., preferably from about 10X to about
90Y., more preferably from about 10X to about 75%, and
even more preferably from about 15X to about 55%, of
fabric conditionin~ composition comprising fabric
conditioning active; and
(B) a polyester non-woven fabric substrate prepared from a
polyester fiber having a denier of from about 2 to about
6, said substrate having a basis weight of from about
0.52 oz/yd2 to about 0.58 oz/yd2, preferably from about
0.53 oz/yd2 to about 0.57 oz/yd2, more preferably from
about 0.54 oz/yd2 to about 0.56 oz/yd2, and a thickness
of from about 0.16 mm to about 0.22 mm, preferably from
about 0.17 mm to about 0.21 mm, more preferably from
~ about 0.18 mm to about 0.20 mm, and, preferably, a tear
strength of at least about 3 lbs/in2 in both the cross
direction and the machine direction, preferably from
about 4 to about 7 lbs/in2 in the cross direction and
from about 3.1 to about 6 lbs/in2 in the machine direc-
tion, said polyester having improved feel character-
istics as compared to conventional substrates of this
type, after said article is used in said automatic
~ WO 95/07342 ' ' ` -' PCT/US94/09939
2 1 7 1 2 8 7 ~; r
- 3
clothes dryer and after said fabric conditioning com-
position has been substantially completely removed from
said substrate.
The "feel" problem associated with the spun-bonded polyester
substrates was not known heretofore so no one knew to look for any
solution to the problem. Surprisingly, when a substrate with a
better feel was prepared by decreasing the heat and pressure to
limit the amount of bonding, the strength of the substrate
actually increased. Therefore, this option for improving feel is
a preferred embodiment. The feel can also be improved by
increased plasticizer usage and/or applying a softener to the
surface of the substrate, especially in combination with, or
after, application of a soil release polymer. The invention
comprises articles comprising spun-bonded polyester substrates
having improved feel after use, regardless of the approach taken.
The active components can contain unsaturation for additional
antistatic benefits. The components are selected so that the
resulting fabric treatment composition has a melting point above
about 38-C and is flowable at dryer operating temperatures.
(A) The Fabric Conditioning Com w sition
The fabric conditioning composition can be any of those known
in the art and/or previously disclosed by others in patent appli-
cations. Compositions that are suitable are disclosed in U.S.
~at. Nos.: 3,944,694, McQueary; 4,073,996, Bedenk et al.;
4,Z37,155, Kardouche; 4,711,730, Gosselink et al.; 4,749,596,
Evans et al.; 4,808,086, Evans et al.; 4,818,569, Trinh et al.;
4,877,896, Maldonado et a, 4,976,879, Maldonado et al.;
5,041,230, Borcher, Sr. et al.; 5,094,761, Trinh et al.;
5,102,564, Gardlik et al.; and 5,234,610, Gardlik et al., all of
said patents being incorporated herein by reference.
Compositions of the present invention can contain from 0% to
about 90X, preferably from OY. to about 80Y., more preferably from
10% to about 70%, and even more preferably from about 20% to about
65Y., of quaternary ammonium compound, preferably ester, and/or
amide linked.
The quaternary ammonium compounds are typicaily of the
Formulas I, II, and mixtures thereof.
WO 95/07342 PCT/US94/09939
~1712~
- 4 -
Formula I comprises:
(R)4-m - N~ - [(CH2)n -(Y)p - R2]m X~
wherein
each Y ~ -0-(O)C-, -N(R)3-C(o)-, -C(o)-N(R)3-, or -C(0)-0-;
m = 1 to 3; n ~ 1 to-4; p - 0 or 1; each R substituent is a
short chain C1-C6, preferably C1-C3, alkyl or hydroxy alkyl
group, e.g., methyl (most preferred), ethyl, hydroxyethyl,
propyl, and the like, benzyl and mixtures thereof; each R2 is
a long chain, saturated and/or unsaturated (Iodine Value -
"IV" of from about 3 to about 60), Cg-C30 hydrocarbyl, or
substituted hydrocarbyl substituent and mixtures thereof; R3
is R or H; and the counterion, X~, can be any softener-com-
patible anion, for example, methylsulfate, ethylsulfate,
chloride, bromide, formate, sulfate, lactate, nitrate and the
like, preferably methylsulfate.
It will be understood that substituents R and R2 of Formula I
can optionally be substituted with various groups such as alkoxyl
or hydroxyl groups.
The preferred ester linked compounds (DEQA) can be considered
to be diester variations of ditallow dimethyl ammonium chloride
(DTDMAC), which is a widely used fabric softener. Preferably, at
least 80X of the DEQA is in the diester form, and from OX to about
20%, preferably less than about 10%, more preferably less than
about 5%, can be DEQA monoester (e.g., only one -y-R2 group). For
optimal antistatic benefit monoester should be low, preferably
less than about 2.5Y.. The level of monoester can be controlled in
the manufacturing of the DEQA.
The~quaternary softening compounds with at least partially
unsaturated alkyl or acyl groups have advantages (i.e., antistatic
benefits) and are highly acceptable for consumer products when
certain conditions are met. Antistatic effects are especially
important where the fabrics are dried in a tumble dryer, and/or
where synthetic materials which generate static are used. Any
reference to IV values hereinafter refers to IV of fatty alkyl or
acyl groups and not to the resulting quaternary, e.g., DEQA
~ WO 95/07342 2171~ 7~ . ~ ` PCTIUS94/09939
- 5 -
compound. As the IV is raised, there is a potential for odor
problems.
For unsaturated softener actives, the optimum storage tem-
perature for stability and fluidity depends on the specific IV of,
e.y., the fatty acid used to make DEQA and/or the level/type of
solvent selected. Exposure to oxygen should be minimized to keep
the unsaturated groups from oxidizing. It can therefore be
important to store the material under a reduced oxygen atmosphere
such as a nitrogen blanket. It is important to provide good
molten storage stability to provide a commercialiy feasible raw
material that will not degrade noticeably in the normal trans-
portation/storage/handling of the material in manufacturing
operations.
The following are non-limiting examples of DEQA Formula I
(wherein all long-chain alkyl substituents are straight-chain):
Saturated
[C2H5]2~N[CH2CH20C(O)C17H35]2 So4CH39
[c3H7][c2H5]~N[cH2cH2oc(o)cllH23]2 S04~CH3
[CH3]2~N[cH2cH2oc(o)R2]2 S04CH3~
where -C(O)R2 is derived from saturated tallow.
Unsaturated
[CH3]20N[cH2cH2oc(o)cl7H3332 S04aCH3
[C2H5]zQN[CH2CH20c(o)cl7H33]2 Cl~ -
[CH2CH20H][CH3]0N[CH2CH20C(O)R2]2 CH3S0
[CH3]20N[CH2CH20C(O)R2]2 CH3S04~
where -C(O)R2 is derived from partially hydrogenated tallow or
modified tallow having the characteristics set forth herein.
In addition to Formula I compounds, the compositions and
articles~ of the present invention comprise DEQA compounds of
Formula II:
N3(Rl)3 - (CH2)n - CH(Q-Tl) - CH2(Q-T2) X~
wherein, for any molecule:
each Q is -0-C(0)- or -(O)C-0-;
each R1 is C1-C4 alkyl or hydroxy alkyl;
each Tl and T2 is a Cg-C30 alkyl or alkenyl group;
n is an integer from 1 to 4; and
WO 95/07342 PCT/US94/09939
~712~7~ ~
X~ is a softener-compatible anion; and wherein preferably R
is a methyl group, n is 1, Q is -O-C(O)-, Tl and T2 are
C14-C1g, and Xa is methyl sulfate.
The straight or branched alkyl or alkenyl chains, T1 and T2,
have from about 8 to about 30 carbon atoms, preferably from about
14 to about 18 carbon atoms, more preferably straight chains
having from about 14 to about 18 carbon atoms.
These compounds can be prepared by standard esterification
and quaternization reactions, using readily available starting
materials. General methods for preparation are disclosed in U.S.
- Pat. No. 4,137,180, incorporated herein by reference.
The composition can also contain a ethoxylated and/or pro-
poxylated sugar derivative contains a "sugar" moiety, e.g., a
moiety derived from, e.g., a polyhydroxy sugar, or sugar alcohol,
that contains from about 4 to about 12 hydroxy groups. This sugar
moiety is substituted by at least one long hydrophobic group,
containing from about 8 to about 30 carbon atoms, preferably from
about 16 to about 18 carbon atoms. For improved physical charac-
teristics, e.g., higher melting point, the hydrophobic group can
contain more carbon atoms, e.g., 20-22, and/or there can be more
than one hydrophobic group, preferably two or, less preferably,
three. In general, it is preferred that the hydrophobic group is
supplied by esterifying one of the hydroxy groups with a fatty
acid. However, the hydrophobic group can be supplied by esteri-
fying the hydroxy group to connect the hydrophobic group to thesugar moiety by an ether linkage, and/or a moiety containing a
carboxy group esterified with a fatty alcohol can be attached to
the sugar moiety to provide the desired hydrophobic group.
Sugar moieties include sucrose, galactose, mannose, glucose.
fructose, sorbitan, sorbitol, mannitol, inositol, etc.~ and/or
their derivatives such as glucosides, galactosides, etc. Other
"sugar" types of moieties containing multiple hydroxy groups can
also be used including starch fractions and polymers such as
polyglycerols. The sugar moiety is any polyhydroxy group that
provides the requisite number of hydroxy groups.
~ WO 95/07342 2 17 12 8 7 PCT/US94/09939
- 7 -
The hydrophobic group can be provided by attachment with an
ester, ether, or other linkage that provides a stable compound.
The hydrophobic group is preferably primarily straight chain, and
preferably contains some unsaturation to provide additional
antistatic benefits. Such hydrophobic groups and their sources
are well known, and are described hereinafter with respect to the
more conventional types of softening agents.
The polyalkoxy chain can be all ethoxy groups, and/or can
contain other groups such as propoxy, glyceryl ether, etc.,
groups. In general, polyethoxy groups are preferred, but for
improved properties such as biodegradability, glyceryl ether
groups can be inserted. Typically there are from about 5 to about
100, preferably from about 10 to about 40, more preferably from
about 15 to about 30, ethoxy groups, or their equivalents, per
molecule.
An empirical formula is as follows:
Rm-(sugar)(RlO)n
wherein R is a hydrophobic group containing from about 8 to about
30, preferably from about 12 to about 22, more preferably from
about 16 to about 18 carbon atoms; "sugar" refers to a polyhydroxy
group, preferably derived from a sugar, sugar alcohol, or similar
polyhydroxy compound; R1 is an alkylene group, preferably ethylene
or propylene, more preferably e~hylene; m is a number from 1 to
about 4, preferably 2; and n is a number from about 5 to about
25 100, preferably from about 10 to about 40. A preferred compound
of this type is polyethoxylated sorbitan monostearate, e.g.,
Glycosperse S-20 from Lonza, which contains about 20 ethoxylate
moieties per molecule.
The~level of the polyethoxy sugar derivative is typically at
least about 5Y., preferably at le~st about 10X, more preferably at
least about 15%. Preferably the maximum level is no more than
about 90%, more preferably no more than about 75%.
The polyethoxy sugar derivative provides improved antistatic
properties to the compositions and can provide equivalent anti-
static properties to conventional dryer added compositions, and/orarticles, even with less, or no, quaternary ammonium softener
WO 9S/07342 2 ~ 71 2B~7t PCTIUS94/09939 ~
materials present. It is possible to prepare a dryer-added
composition, or article, that is entirely nonionic.
Fabric softening compositions employed herein can also
contain, as a preferred component, at a level of from about 0% to
about 95Y, preferably from about 10% to about 75YO~ more preferably
from about 20% to about 60%, carboxylic acid salt of a tertiary
amine which has the formula:
R5 - N (R6)(R7)- H(+)(-)0 - C(0) - R8
wherein R5 is a long chain aliphatic group containing from about 8
to about 30 carbon atoms; R6 and R7 are the same or different from
each other and are selected from the group consisting of aliphatic
groups containing from about 1 to about 30 carbon atoms, hydroxy-
alkyl groups of the Formula R40H wherein R4 is an alkylene group
of from about 2 to about 30 carbon atoms, and alkyl ether grbups
of the formula R90(CnH2no)m wherein R9 is alkyl and alkenyl of
from about 1 to about 30 carbon atoms and hydrogen, n is 2 or 3,
and m is from about 1 to about 30, and wherein R8 is selected from
the group consisting of unsubstituted alkyl, alkenyl, aryl,
alkaryl and aralkyl of about 1 to about 30 carbon atoms, and
substituted alkyl, alkenyl, aryl, alkaryl, and aralkyl of from
about 1 to about 30 carbon atoms wherein the substituents are
selected from the group consisting of halogen, carboxyl, and
hydroxyl, said composition having a melting point of from about
35-C to about 100-C.
This component can provide the following benefits: superior
odor, a decrease in paint softening of the dryer drum, and/or
improved fabric softening performance, compared to similar
articles without this component. Either R5, R6, R7, and/ar R8
chains can contain unsaturation for improved antistatic benefits.
Tertiary amine salts of carboxy~ic acids have superior
chemical stability, compared to primary and secondary amine
carboxylate salts. For example, primary and secondary amine
carboxylates tend to form amides when heated, e.g., during pro-
cessing or use in the dryer. Also, they absorb carbon dioxide,
thereby forming high melting carbamates which build up as an
undesirable residue on treated fabrics.
WO 95107342 2 ~ 8 7. PCT/US94/09939
Preferably, R5 is an aliphatic chain containing from about 12
to about 30 carbon atoms, R6 is an aliphatic chain of from about 1
to about 30 carbon atoms, and R7 is an aliphatic chain of from
about ~ to about 30 carbon atoms. Particularly preferred tertiary
amines for static control performancé are those containing unsatu-
ration; e.g., oleyldimethxlamine and/or soft tallowdimethylamine.
Examples of preferred tertiary amines as starting material for the
reaction between the amine and carboxylic acid to form the
tertiary amine salts are: lauryldimethylamine, myristyldimethyl-
amine, stearyldimethylamine, tallowdimethylamine, coconutdimethyl-
amine, dilaurylmethylamine, distearylmethylamine, ditallowmethyl-
amine, oleyldimethylamine, dioleyl methylamine, lauryldi(3-hy-
droxypropyl)amine, stearyldi(2-hydroxyethyl)amine, trilaurylamine,
laurylethylmethylamine, and C18H37N[(C2H4)10H]2-
Preferred fatty acids are those wherein R8 is a long chain,
unsubstituted alkyl or alkenyl group of from about 8 to about 30
carbon atoms, more preferably from about 11 to about 17 carbon
atoms. Examples of specific carboxylic acids as a starting
material are: formic acid, acetic acid, lauric acid, myristic
acid, palmitic acid, stearic acid, oleic acid, oxalic acid, adipicacid, 12-hydroxy stearic acid, benzoic acid, 4-hydroxy benzoic
acid, 3-chloro benzoic acid, 4-nitro benzoic acid, 4-ethyl benzoic
acid, 4-(2-chloroethyl)benzoic acid, phenylacetic acid, (4-chloro-
phenyl)acetic acid, (4-hydrGxyphenyl)acetic acid, and. phthalic
~5 acid.
Preferred carboxylic acids are stearic, oleic, lauric,
myristic, palmitic, and mixtures thereof.
The amine salt can be formed by a simple addition reaction,
well ~n4wn in the art, disclosed in U.S. Pat. No. 4,237,155,
Kardouche, issued Dec. 2, 1980. Excessive levels of free amines
may result in odor problems, and generally free amines provide
poorer softening performance than the amine salts.
Preferred amine salts for use herein are those wherein the
amine moiety is a Cg-C30 alkyl or alkenyl dimethyl amine or a
di-Cg-C30 alkyl or alkenyl methyl amine, and the acid moiety is a
Cg-C30 alkyl or alkenyl monocarboxylic acid. The amine and the
acid, respectively, used to form the amine salt will often be of
W095/07342 ~1712~7~: PCT/US94/09939 ~
- 10 -
mixed chain lengths rather than single chain lengths, since these
materials are normally derived from natural fats and oils, or
synthetic processed which produce a mixture of chain lengths.
Also, it is often desirable to utilize mixtures of different chain
lengths in order to modify the physical or performance character-
istics of the softening composition.
Specific preferred amine salts for use in the present inven-
tion are oleyldimethylamine stearate, stearyldimethylamine stear-
ate, stearyldimethylamine myristate, stearyldimethylamine palmi-
tate, distearylmethylamine palmitate, distearylmethylamine laur-
ate, and mixtures thereof. A particularly preferred mixture is
oleyldimethylamine stearate and distearylmethylamine myristate, in
a ratio of 1:10 to 10:1, preferably about 1:1.
O~tional Inqredients
Well known optional components included in fabric condition-
ing compositions are narrated in U.S. Pat. No. 4,103,047, Zaki et
al., issued July 25, 1978, for "Fabric Treatment Compositions,"
incorporated herein by reference.
(1) ODtional Nonionic Softener
A highly preferred optional ingredient is a nonionic fabric
softening agent/material. Typically, such nonionic fabric
softener materials have an HLB of from about 2 to about 9, more
typically from about 3 to about 7. In general, the materials
selected should be relatively crystalline, higher melting, (e.g.,
>25-C).
The level of optional nonionic softener in the solid compo-
sition is typically from about 10% to about 50Y" preferably from
about 15Y. to about 40%.
Pre~ferred nonionic softeners are fatty acid partial esters of
polyhydric alcohols, or anhydrides thereof, wherein the alcohol,
or anhydride, contains from about 2 to about 18, preferably from
about 2 to about 8, carbon atoms, and each fatty acid moiety
contains from about 8 to about 30, preferably from about 16 to
about 20, carbon atoms. Typically, such $ofteners contain from
about one to about 3, preferably about 2 fatty acid groups per
molecule.
WO95/07342 2 ~112 B 7 ,t ~ PCT/US94/09939
- 11 -
The polyhydric alcohol portion of the ester can be ethylene
glycol, glycerol, poly (e.g., di-, tri-, tetra, penta-, and/or
hexa-) glycerol, xylitol, sucrose, erythritol, pentaerythritol,
sorbitol or sorbitan. These nonionic fabric softening materials
do not include the ethoxylated sugar derivatives disclosed here-
inbefore. They typically contain no more than about 4 ethoxy
groups per molecule.
The fatty acid portion of the ester is normally derived from
fatty acids having from about 8 to about 30, preferably from about
16 to about 20, carbon atoms. Typical examples of said fatty
acids being lauric acid, myristic acid, palmitic acid, stearic
acid, oleic acid, and behenic acid.
Highly preferred optional nonionic softening agents for use
in the present invention are C1o-C26 acyl sorbitan esters and
polyglycerol monostearate. Sorbitan esters are esterified dehy-
dration products of sorbitol. The preferred sorbitan ester
comprises a member selected from the group consisting of C10-c26
acyl sorbitan monoesters and C10-c26 acyl sorbitan diesters and
ethoxylates of said esters wherein one or more of the unesterified
hydroxyl groups in said esters contain from 1 to about 4 oxyethyl-
ene units, and mixtures thereof. For the purpose of the present
invention, sorbitan esters containing unsaturation (e.g., sorbitan
monooleate) are preferred.
Sorbitol, which is typically prepared by the catalytic
hydrogena$ion of glucose, can be dehydrated in well known fashion
to form mixtures of- 1,4- and I,5-sorbitol anhydrides and small
amounts of isosorbides. (See U.S. Pat. No. 2,322,821, Brown,
issued June 29, 1g43, incorporated herein by reference.)
Th~ foregoing types of complex mixtures of anhydrides of
sorbitol are collectively referred to herein as "sorbitan." It
will be recognized that this "sorbitan" mixture will also conta~n
- some free, uncyclized sorbitol.
The preferred sorbitan softening agents of the type employed
- herein can be prepared by esterifying the "sorbitan" mixture with
a fatty acyl group in standard fashion, e.g., by reaction with d
fatty acid halide, fatty acid ester, and/or fatty acid. The
esterification reaction can occur at any of the available hydroxyl
WO 95/07342 PCT/US94/09939
~L7~L287~ Jl,,
- 12 -
groups, and various mono-, di-, etc., esters can be prepared. In
fact, mixtures of mono-, di-, tri-, etc., esters almost always
result from such reactions, and the stoichiometric ratios of the
reactants can be simply adjusted to favor the desired reaction
product.
For commercial production of the sorbitan ester materials,
etherification and esterification are generally accomplished in
the same processing step by reacting sorbitol directly with fatty
acids. Such a method of sorbitan ester preparation is described
more fully in MacDonald; "Emulsifiers:" Processing and Quality
Control:, Journal of the American Oil Chemists' SocietY, Vol. 45,
October 1968.
Details, including formula, of the preferred sorbitan esters
can be found in U.S. Pat. No. 4,128,484, incorporated hereinbefore
by reference.
For the purposes of the present invention, it is preferred
that a significant amount of di- and tri- sorbitan esters are
present in the ester mixture. Ester mixtures having from 20-50%
mono-ester, 25-50% di-ester and 10-35~, of tri- and tetra-esters
are preferred.
The material which is sold commercially as sorbitan mono-
ester (e.g., monostearate) does in fact contain significant
amounts of di- and tri-esters and a typical analysis of commercial
sorbitan monostearate indicates that it comprises-about 27% mono-,
32~, di- and 30% tri- and tetra-esters. Commercial sorbitan
monostearate therefore is a preferred material. Mixtures of
sorbitan stearate and sorbitan palmitate having stearate/palmitate
weight ratios varying between 10:1 and 1:10, and 1,5-sorbitan
esters are useful. Both the 1,4- and 1,5-sorbitan esters are
useful herein.
Other useful alkyl sorbitan esters for use in the softening
compositions herein include sorbitan monolaurate, sorbitan mono-
myristate, sorbitan monopalmitate, sorbitan monobehenate, sorbitan
monooleate, sorbitan dilaurate, sorbitan dimyristate, sorbitan
dipalmitate, sorbitan distearate, sorbitan dibehenate, sorbitan
dioleate, and mixtures thereof, and mixed tallowalkyl sorbitan
mono- and di-esters. Such mixtures are readily prepared by
WO 9S/07342 PCT/US94/09939
~ 1 7 ~1 2 ~3 7
- 13 -
reacting the foregoing hydroxy-substituted sorbitans, particularly
the 1,4- and 1,5-sorbitans, with the corresponding acid or acid
chloride in a simple esterification reaction. It is to be recog-
nized, of course, that commercial materials prepared in this
manner will comprise mixtures usually containing minor proportions
of uncyclized sorbitol, fatty acids, polymers, isosorbide struc-
tures, and the like. In the present invention, it is preferred
that such impurities are present at as low a level as possible.
The preferred sorbitan esters employed herein can contain up
10 to about 15Y. by weight of esters of the C2o-C26, and higher, fatty
acids, as well as minor amounts of Cg, and lower, fatty esters.
Glycerol and polyglycerol esters, especially glycerol,
diglycerol, triglycerol, and polyglycerol mono- and/or di- esters,
preferably mono-, are also preferred herein (e.g., polyglycerol
monostearate with a trade name of Radiasurf 7248). Glycerol
esters can be prepared from naturally occurring triglycerides by
normal extraction, purification and/or interesterification pro-
cesses or by esterification processes of the type set forth
hereinbefore for sorbitan esters. Partial esters of glycerin can
also be ethoxylated with no more than about 4 ethoxy groups per
molecule to form usab1~ derivatives that are included within the
term "glycerol esters."
Useful glycerol and polyglycerol esters include mono-esters
with stearic, oleic, palmitic, lauric, isostearic, myristic,
and/or behenic acids and the diesters of stearic, oleic, palmitic,
lauric, isostearic, behenic, and/or myristic acids. It is under-
stood that the typical mono-ester contains some di- and tri-ester,
etc.
Th~ "glycerol esters" also include the polyglycerol, e.g.,
diglycerol through octaglycerol esters. The polyglycerol polyols
are formed by condensing g~ycerin or epichlorohydrin together to
link the glycerol moieties via ether linkages. The mono- and/or
diesters of the polyglycerol polyols are preferred, the fatty acyl
groups typically being those described hereinbefore for the
sorbitan and glycerol esters.
W O 95/07342 PCTAUS94/09939
2171287
, , 1.4 -
(3) ODtional Soil Release Aqent
Optionally, the compositions herein contain from 0% to about
10X, preferably from about 0.1% to about 5%, more preferably from
about 0.1% to about 2%, of a soil release agent. Preferably, such
a soil release agent is a polymer. Polymeric soil release agents
useful in the present invention include copolymeric blocks of
terephthalate and polyethylene oxide or polypropylene axide~ and
the like. U.S. Pat. No. 4,956,447, Gosselink/Hardy/Trinh, issued
Sept. 11, 1990, discloses specific preferred soil release agents
comprising cationic functionalities, said patent being incorpo-
rated herein by reference.
A preferred soil release agent is a copolymer having blocks
of terephthalate and polyethylene oxide. More specifically, these
polymers are comprised of repeating units of ethylene and/or
propylene terephthalate and polyethylene oxide terephthalate at a
molar ratio of ethylene terephthalate-units to polyethylene oxide
terephthalate units of from about 25:75 to about 35:65, said
polyethylene oxide terephthalate containing polyethylene oxide
blocks having molecular weights of from about 300 to about 2000.
The molecular weight of this polymeric soil release agent is in
the range of from about 5,000 to about 55,000.
U.S. Pat. No. 4,976,879, Maldonado/Trinh/Gosselink, issued
Dec. 11, 1990, discloses specific preferred soil release agents
which can also provide improved antistat benefit, said patent
being incorporated herein by reference.
Another preferred polymeric soil release agent is a crystal-
lizable polyester with repeat units of ethylene terephthalate
units containing from about 10% to about 15% by weight of ethylene
terephthalate units together with from about 10Y. to about 50~ by
weight of polyoxyethylene terephthalate units, ~erived from a
polyoxyethylene glycol of average ~olecular weight of from about
300 to about 6,000, and the molar ratio of ethylene terephthalate
units to polyoxyethylene terephthalate units in the crystallizable
polymeric compound is between 2:1 and 6:1. Examples of this
polymer include the commercially available materials Zelcon~ 4780
(from DuPont) and Milease~ T (from ICI).
WO 95/07342 `~ PCT/US94/09939
~171287
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(4) Cvclodextrin/Perfume ComDlexes and Free Perfume
The products herein can also contain from about 0.5~, to about
60%, preferably from about lYo to about 50%, cyclodextrin/perfume
inclusion complexes, as disclosed in U.S. Pat. Nos. 5,139,687,
Borcher et al., issued Aug. 18, 1992; and 5,234,610, Gardlik et
al., to issue Aug. 10, 1993, which are incorporated herein by
reference. Perfumes are highly desirable, ca~ usually benefit
from protection, and can be complexed with cyclodextrin. Fabric
softening products typically contain perfume to provide an olfac-
~o tory aesthetic benefit and/or to serve as a signal that the
product is effective.
The perfume ingredients and compositions of this invention
are the conventional ones known in the art. Selection of any
perfume component, or amount of perfume, is based solely on
aesthetic considerations. Suitable perfume compounds and compo-
sitions can be found in the art including U.S. Pat. Nos.:
4,145,184, Brain and Cummins, issued Mar. 20, 1979; 4,209,417,
Whyte, issued June 24, 1980; 4,515,705, Moeddel, issued May 7,
1985; and 4,152,272, Young, issued May 1, 1979, all of said
patents being incorporated herein by reference. Many of the art
recognized perf~me compositions are relatively substantive, as
described hereinafter, to maximize their odor effect on sub-
strates. However, it is a special advantage of perfume delivery
via the perfume/cyclodextrin complexes that nonsubstantive per-
fumes are also effective. The volatility and substantivity ofperfumes is disclosed in U.S. Pat. No. 5,234,610, supra.
If a product contains both free and complexed perfume, the
escaped perfume from the complex contributes to the overall
perfume ~odor intensity, giving rise to a longer lasting perfume
odor impression.
As disclosed in U.S. Pat. No. 5,234,610, supra, by adjusting
the levels of free perfume and perfume/CD complex it is possible
to provide a wide range of unique perfume profiles in terms of
timing (release) and/or perfume identity (character). Solid,
dryer-activated fabric conditioning compositions are a uniquely
desirable way to apply the cyclodextrins, since they are applied
at the very end of a fabric treatment regimen when the fabric is
WO 9S/07342 PCT/US94/09939 ~
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clean and when there are almost no additional treatments that can
remove the cyclodextrin.
(5) Stabilizers
Stabilizers can be present in the compositions of the present
invention. The term "stabilizer," as used herein, includes
antioxidants and reductive agents. These agents are present at a
level of from OY. to about 2%, preferably from about 0.01Y. to about
0.2%, more preferably from about 0.05% to about 0.1Y. for antioxi-
dants and more preferably from about 0.01Y. to about 0.2% for
reductive agents. These assure good odor stability under long
- term storage conditions for the compositions. Use of antioxidants
and reductive agent stabilizers is especially critical for
unscented or low scent products (no or low perfume).
Examples of antioxidants that can be added to the compo-
sitions of this invention include ascorbic acid, ascorbic pal-
mitate, propyl gallate, available from Eastman Chemical Products,
Inc., under the trade names Tenox~ PG and Tenox S-1; a mixture of
BHT, BHA, propyl gallate, and citric acid, available from Eastman
Chemical Products, Inc., under the trade name Tenox-6; butylated
hydroxytoluene, available from UOP Process Division under the
trade name Sustane2 BHT; tertiary butylhydroquinone, Eastman
Chemical Products, Inc., as Tenox TBHQ; natural tocopherols,
Eastman Chemical Products, Inc., as Tenox GT-1/GT-2; and butylated
hydroxyanisole, Eastman Chemical Products, Inc., as BHA.
Examples of reductive agents include sodium borohydride.
hypophosphorous acid, and mixtures thereof.
The stability of the compounds and compositions herein can be
helped by the stabilizers, but in addition, the preparation of
compounds used herein and the source of hydrophobic groups can be
important. Surprisingly, some highly desirable, readily available
sources of hydrophobic groups such as fatty acids from, e.g..
tallow, possess odors that remain with the compound, e.g., DEQA
despite the chemical and mechanical processing steps which convert
the raw tallow to finished DEQA. Such sources must be deodorized~
e.g., by absorption, distillation (including stripping such ~s
steam stripping), etc., as is well known in the art. In addition~
care must be taken to minimize contact of the resulting fatty acyl
W0951~7342 21712~8~ .` PCT/IIS9J/09939
groups to oxygen and/or bacteria by adding antioxidants, anti-
bacterial agents, etc. The additional expense and effort asso-
ciated with the unsaturated fatty acyl groups is justified by the
superior performance which has not been recognized.
(6) Other OPtional Inqredien~s
The present invention can include other optional components
(minor components) conventionally used in textile treat~ent
compositions, for example, colorants, preservatives, optical
brighteners, opacifiers, physical stabilizers such as guar gum and
}O polyethylene glycol, anti-shrinkage agents, anti-wrinkle agents,
fabric crisping agents, spotting agents, germicides, fungicides,
anti-corrosion a~ents, antifoam agents, and the like.
(B) The Substrate
The present invention relates to articles of manufacture
comprising a substrate that has been modified to provide superior
feel and acceptability after use.
Representative articles and their components are those that
are adapted to soften fabrics in an automatic laundry dryer,
including the ones disclosed in U.S. Pat. Nos.: 3,989,631 Marsan,
issued Nov. 2, 1976; 4,055,248, Marsan, issued Oct. 25, 1977;
4,073,996, Bedenk et al., issued Feb. 14, 1978; 4,022,938, Zaki et
al., issued May 10, 1977; 4,764,289, Trinh, issued Aug. 16, 1988;
4,808,086, Evans et al., issued Feb. 28,1989; 4,103,047, Zaki et
al., issued July 25, 197.8; 3,736,668, Dillarstone, issued June 5,
1973; 3,701,202, Compa et al., issued Oct. 31,1972; 3,634,947,
Furgal, issued Jan. 18, 1972; 3,633,538, Hoeflin, issued Jan. 11,
1572; and 3,435,537, Rumsey, issued Apr. 1, 1969; and 4,000,340,
Murphy et al., issued Dec. 28, 1976, all of said patents being
incorporated herein by reference.
The fabric treatment compositions are provided as an article
of manufacture in combination with the flexible substrate as
described hereinafter. The substrates herein effectively release
the composition (AJ in an automatic laundry (clothes) dryer.
The substrate dispensing means will normally carry an effec-
tive amount of fabric treatment composition. Such effective
amount typically provides sufficient fabric conditioning/anti-
static agent and/or anionic polymeric soil release agent for at
WO 9S/07342 PCTrUS94/09939 ~
2~71287
- 18 -
least one treatment of a~mi~imum load in an automatic laundry
dryer. Amounts of fabric treatment composition for multiple uses,
e.g., up to about 30, can be used. Typical amounts for a single
article can vary from about 0.25 9 to about 100 9, preferably from
about 0.5 9 to about 20 9, most preferably from about 1 9 to about
10 9.
The substrates useful herein are polyester non-woven fabrics
having basis weights of from about 0.52 oz~yd2 to about 0.58
oz/yd2, preferably from about 0.53 oz/yd2 to about 0.57 oz/yd2,
more preferably from about 0.54 oz/yd2 to about 0.56 oz/yd2.
These substrates are prepared using polyester fibers having
deniers of from about 2 to about 6, preferably from about 3 to
about 5, and more preferably about 4. Typically, the fiber is a
continuous filament that is laid down, in a pattern that results
in a multiplicity of layers and intersections between overlayed
portions of the filament, on a belt, preferably foraminous, and
then the fiber intersections are fused into fiber-to-fiber bonds
by a combination of heat and pressure, typically a temperature of
about 237-C and a roll pressure of about 40 lbs/sq-in. It has now
been discovered, that reducing the temperature to from about 237-C
to about 231-C, preferably to from about 237-C to about 233-C,
more preferably from about 237-C to about 235-C and/or pressure of
from about 40 pSi9 to about 10 psig, more preferably from about 10
psig to about 0 psig, provides increased thickness (loft), a
25 softer substrate, especially after use, increased fuzziness,
especially on the belt side of the substrate, and, most surpris-
ingly, no loss of strength or an actual improvement in strength.
The conditions can be varied, but are adjusted to provide at least
a 14X i~ncrease in thickness, more preferably at least a 29%
30 increase in thickness, from about 0.14 mm for the standard con-
ditions, to at least about 0.16 mm, more preferably at least about
0.18 mm. The fuzziness, as rated by a panel on a scale of from 1
to 5, where 1 is high fuzz, improves from about 4 to about 2.9 on
the outside (non-belt or "jet" side where the air jets are
35 located) and from about 4.4 to about 1.9 on the belt side of the
substrate. The typical polyester substrate used heretofore is
significantly less soft after use than a rayon substrate whereas
~ W0 95/07342 ~ 1 7 1 ~ 8 7 ~ PCT/US94/09939
_ 19 _
the polyester substrates herein, especially those formed with
lower temperature and lower pressure are not significantly less
soft than a commercial rayon substrate.
In addition to the above noted improvements in the physical
characteristics, the breaking strengths remain at least about 3
lbs/sq-in in each direction. I.e., from about 3 to about 14,
preferably from about 6 to about 12, more preferably from abDut 7
to about 9, lbs/sq-in. These substrates are fabricated from
polyester fibers having a denier from about 2 to about 6, prefer-
a~ly from about 3 to about 5, more preferably about 4.
The fabrics are typicallv prepared by laying a thin layer offiber on a moving foraminous belt and then applying heat to melt
at least a portion of the surfaces of the fibers and applying heat
to fuse the adjacent fibers to each other at their intersections.
The amount of heat and pressure is adjusted to provide the desired
bonding.
Usaae
The articles of this invention can be used for imparting the
fabric treatment composition to fabric (clothes) to provide
softening and/or antistatic effects to fabric in an automatic
laundry dryer. Generally, the method of using the articles of the
present invention comprises: commingling pieces of damp fabric by
tumbling said fabric under heat in an automatic clothes dryer with
an article comprising an effective amount of composition.(A). The
composition should have a melting point greater than about 35-C be
flowable at dryer operating temperature.
The present invention relates to improved solid dryer-acti-
vated fabric softener articles which have improved acceptability
to the consumer.
All percentages, ratios, and parts herein, in the ~pecifi-
cation, Examples, and Claims, are by weight and are approximations
unless otherwise stated.
The following are nonlimiting examples of the instant
articles, methods, and compositions of the present invention.
WO 95/07342 PCT/IJS91/09939
2171287
- 20 -
EXAMPLE 1
Com~onents Wt.%
Ditallowdimethylammonium sulfate 21.04
Stearyldimethylamine Stearic Acid'
Salt* 32.83
Perfume/Cyclodextrin Complex 19.36
Clay** 3 79
Perfume 1.56
Sodium C12 Alkylbenzene Sulfonate 0.38
Sorbitan Monostearate 21.04
100.0
*1:2 ratio of stearyldimethylamine:triple-pressed stearic acid.
**Calcium bentonite clay, Bentolite L, sold by Southern Clay
Products, or Gelwhite GP clay.
PREPARATION OF THE SUBSTRATE
The substrate was prepared in a conventional manner with the
only changes being in the bonding temperature (from about 237-C to
about 235-C) and the consolidating pressures (from about 40 psig
to about O psig for the nip roll and from about 10 psig to about
4.5 psig for the consolidation roll steam pressure). The sub-
strate prepared by the conventional process compares to the
improved substrate as follows: Fuzz rating (1 to 5 grade with 1
being most preferred) Jet Fuzz 4.0 vs. 2.9 and Belt side Fuzz 4.4
vs. 1.9; Tearing tensile strength (lbs/in) cross direction 3.3 vs.
5.7 and machine direction 3.7 vs. 4.5; Softness vs. Rayon (-4 to
+4 grade with positive numbers indicating a preference) -2.79
(significantly worse) vs. -0.58 (not significantly different).
PREPARATION OF FABRIC CON~ITIONING SHEETS
The coating mixture is applied to the said improved substrate
sheets (22.86 cm. by 22.86 cm., about 523 sq.cm. having a weight
of about 1 gm) The substrate sheets are comprised of about
4-denier spun bonded polyester. The molten fabric conditioning
composition is applied with an impregnation,head and drawn between
two heated rollers to impregnate the substrate and remove excess
composition. The softener composition is applied in an amount of
WO 95/07342 ~ 1712 8 7 PCT/US94/09939
- 21 -
about 2.38 gm per sheet. When the sheets (articles) are used by
consumers, they are preferred for softness as compared to sheets
prepared with existing substrates and are not significantly
different from prior art rayon substrate articles.
