Note: Descriptions are shown in the official language in which they were submitted.
-1- 1340a~8
TITLE
STAIN-RESISTANT AGENTS FOR TEXTILES
FIELD OF THE INVENTION
The present invention relates to stain-resistant
comp~sitions comprising sulfonated phenol-formaldehyde
condensation products and polymers of ethylenically
unsaturated aromatic monomers, polyamide textile
substrates treated with the same, and processes for their
preparation. The stain-resistant compositions and
substrates of' this invention possess stain resistance that
is as good as or better than previously known compositions
and substrates but do not suffer from yellowing to the
extent that previously known materials do.
BACKGROUND OF THE INVENTION
Polyamide substrates, such a, carpeting,
upholstery fabric and the like, are subject to staining by
a variety of agents, e.g., foods and beverages. An
especially troublesome staining agent is FD&C Red Dye No.
40, ,-ommonly found in soft drink preparations. Different
types of treatments have been proposed to deal with
staining problems. One approach is to apply a highly
fluorinated polymer to the substrate. Another is to use a
composition containing a sulfonated phenol-formaldehyde
condensation product
For example, ~iss and Beck, in Canadian
patent application No. 529,364, filed -l987 February 10
:30 disclose stain--resistant synthetic polyamide
textile substrates having modified sulfonated phenol
*
-2- 1340028
formaldehyde polymeric condensation products deposited
on them.
Blyth and Ucci, in U.S. Patent 4,592,940,
describe the preparation of stain-resistant nylon
carpet by immersing the carpet in an aqueous solution
oE a sulfonated condensation polymer wherein at least
40% of the polymer units contain -503X radicals and at
least 40% of the polymer units contain sulfone
l:inkages. On the other hand, in U.5. Patent 4,501,591,
Ucci and Blyth disclose continuously dyeing polyamide
carpet fibers in the presence of an alkali metal meta
silicate and a sulfonated phenol-formaldehyde
condensation product so as to impart stain resistance
to the dyed carpet. They report that in experiments in
which either the alkali meta silicate or condensation
product was omitted from the dyeing process, or in
which silicates other than the alkali metal meta
silicates were used, they failed to obtain
s~ain-resistant carpets (column 8, lines 4-12).
Frickenhaus et al., in U.S. Patent 3,790,344,
disclose a process for improving fastness to wet
processing of dyeings of synthetic polyamide textile
materials with anionic or cationic dye stuffs. After
dyeing the textile materials, Frickenhaus et al.
treated the dyed materials with condensation products
prepared from 4,4'-dioxydiphenylsulphon, formaldehyde
and either a phenol sulfonic acid, a naphthalene
sulfonic acid, sodium sulfite or sodium hydrogen
sulfite.
However, sulfonated phenol-formaldehyde
condensation products are themselves subject to
discoloration; commonly they turn yellow. Yellowing
problems are described by W. H. Hemmpel in a March 19,
1982 article in ~erica's Texti~es, entitled Reversi~le
Yellowinq No_ Finisher's Fault. Hemmpel attributes
13~28
-- 3 --
yellowing to exposure of a phenol-basec finish to nitrogen
oxides and/or ultraviolet radiation. Critchley et al.,
Heat ~esistant Polymers: Technoloqically Useful Materials,
Plenum Press, N.Y. 19~33, state that the thermo-oxidative
stability of phenol-formaldehyde condersation products can
be improved by etherifying or esterifying the phenolic
hydroxyl groups.
To deal with the yellowing p~oblem, Marshall,
U.S. Patent 4,833,009, issued 1989 May 23, removes color-
formers by dissolving the condensation product in aqueous
base, acidifying the solution to form a slurry, heating
the slurry so as to cause phase separation, recocering
water-insoluble mater:ial and dissolving the water-
inso]uble material in aqueous base. Or the other hand,
Liss and Beck, in the:ir aforesaid application/ remove
color-formers by acylating or etherifying some of the
phenolic hydroxyls of the condensation product, and in a
preferred embodiment, dissolving the mcdified condensation
product in a hydroxy-containing solvent, such as ethylene
glycol, prior to its being applied to the textile
subst:rate.
Orito et al., in Japanese Published Patent
Application Topkukai 48-1214, describe preparing flame-
reta~dant filaments by (a~ reacting (i) a phenol-
containing compound, (ii) benzoquanamire, melamine or a
methylol derivative thereof and (iii) formaldehyde; (b)
forming filaments by rnelt-spinning the resulting polymer
and l~c) reacting the :Eilaments with an esterifying or
etherifying agent so as to effect color change in the
filaments. In an example, soaking the filaments in acetic
anhyclride for five days caused their color to change from
pink to pale yellow.
X
l;
I 34~28
Meister et al., in U.K. Patent Specification
1 291 784, disclose condensation products of
4,4'-dihydroxydiphenylsulphone, diarylether sulphonic
acids and formaldehyde, and the use of such
condensation products as tanning agents and as agents
for improving the fastness to wet processing of dyeings
obtained on synthetic polyamides with anionic and/or
cationic dyestuffs. Meister et al. disclose that by
preparing their condensation products in an acid pH
range, leathers tanned with the condensation products
showed practically no yellowing after 100 hours
exposure to light in Xenotest apparatus.
Allen et al., in U.S. Patent 3,835,071,
disclose rug shampoo compositions which upon drying
leave very brittle, non-tacky residues which are easily
removed when dry. The compositions comprise water-
soluble metal, ammonium or amine salt of a styrene-
maleic anhydride copolymer, or its half ester, and a
detergent. Water-soluble metal salts of Group II and
the alkali metals (particularly magnesium and sodium)
are preferred, and ammonium salts are most preferred by
Allen et al.
BRIEF SUMMARY OF THE INVE~TION
The present invention provides compositions
containing a sulfonated phenol-formaldehyde
condensation product and a hydrolyzed polymer of maleic
anhydride and one or more ethylenically unsaturated
aromatic monomers, polyamide textile substrates treated
~ith such compositions so as to impart stain resistance
to the substrates, and methods for imparting stain
resistance to textile substrates by use of the
compositions of this invention.
134~28
--5--
DETAILED DESCRIPTION O~ THE INVENTION
The compositions of the present invention are
effective over a wide range of proportions of the
modified polymeric: sulfonated phenol-formaldehyde
condensation products and the hydrolyzed polymers of
maleic anhydride and ethylenically unsaturated aromatic
monomers. A useful ratio is one in the range between
about 5 and 70 percent by weight of said condensation
product and between about 95 and 30 percent by weight
of said maleic anhydride polymer. Preferably the ratio
is in the range between about 10 and 60 percent by
weight of said polymeric condensation product and
between 90 and 40 percent by weight of said maleic
anhydride polymer. When applied to a textile substrate
so as to augment an existing stainblocking treatment
(e.g. the type treatment disclosed by Liss and Beck),
the composition most preferably contains about 15
weight percent of said condensation product and about
85 weight percent of said maleic anhydride polymer.
When applied to a substrate under mill conditions (e.g.
in a Beck or Continuous Dyer), a composition containing
about 90 to 70 weight of said maleic anhydride polymer
and about 10 to 30 weight percent of said condensation
product is most preferred. When applied in place to
substrate which has had no prior stainblocking
treatment, or one that is deficient as a stain blocker,
a composition containing about 50 weight percent of
both said condensation product and said maleic
anhydride polymer (e.g. in a shampoo formulation) is
most preferred. In addition, such a shampoo
formulation is preferred for maintaining stainbloc~ing
performance of carpeting after trafficking in
commercial establishments. As compared to a
composition containing 100 pe~-cent of said condensation
product, ~he compositions of this invention exhib~t
13401~8
less initicll discoloration and better light-fastness.
Mcreover, the compositions of this ~nvention provide
better stain resistance than do the.r individual
components at equivalent levels of treatment, based on
t~,e weight of the textile substrate being treated.
The polymeric sulfonated phenol-formalde~yde
condensation products which can be used for the
purposes of this invention are any of those described
in the prior art as being useful as dye-resist agents
or dye-fixing agent:s, in other words, dye-reserving
acTents or agents which improve wetfastness of dyeings
on polyamide fibers. See for example the Blyth et al.,
Ucci et al., Fric~enhaus et al. and Meister et al.
patents cited above. Examples of commercially
available condensat:lon products suitable for the
invention are t~e MESITOL NBS product of Mobay Chemical
Corporation (a conclensation product prepared from
b~s(4-hydroxypheny])-sulfone, forma'ldehyde, and phenol
sulfonic acid; U.S. Patent ~o. 3,790,344), as well as
Erional NW (formed by condensing a mixture of
naphthalene mo~osulfonic acid, bis(hydroxyphenyl)
sulfone and formalclehyde; U.S. Pate~t No. 3,716,393).
In a preferred embodiment, the condensation products
are those d~sclosed by Marshall ~nd by Liss
and Beck in their patent and patent application,
respectively, described above. The techniques disclosecl
by Marshall and by Liss and Beck are essentially
eqiuivalent in removing color-formers; however, that of
Mairshall avoids the use of organic solvents and their
undesirable biological oxygen deman~ in water. After
removal of color-formers by use of the Marshall and the
Liss and Beck processes, the modified sulfonated
polymeric phenol-formaldehyde condensation products
comprise ones in which between about lO to 25% of the
polymer units thereof contain SO3(-;l radicals,
* denotes trade mark
~2
L~
_7_ I 3 4~ ~28
and about 90 to 75~ of the polymer units contain
sulfone radicals.
The hydro~ized polymer of maleic anhydride
and one or ~ore ethylenically unsaturated aromatic
monomers suitable for the purposes of this invention
and their preparation are those described by
Fitzgerald, Rao, Vinod, Henry and Prowse in Canadian
application Serial No. 586,056 filed of even date
herewith. Those po]ymers contain bet:ween about one and
two polymer units derived from one or more
ethylenically unsaturated aromatic monomers per polymer
unit derived from maleic
anhydride (hydrolyzed polymers conta,ning three
ethylenically unsaturated aromatic polymer units per
maleic anhydride po:Lymer unit are not: suitable).
Hydrolyzed polymers containing about one polymer unit
derived from one or more ethylenical y unsaturated
arcmatic monomers per polymer unit derived from maleic
anhydride are most effective in imparting stain
recistance to textiLe substrates. A variety of
ethylenically unsaturated aromatic compounds can be
used for the purpose of preparing the hydrolized
polymers of this invention. They can be represented
by the formula
2S
R
~ ~3
R4
,,~ f
134002~
-- 8
where.~in
]~2
R is R'-CH=C'- or CH2=CH-CH2-;
Rl i s H-, CH3- or
R2 is H- or CHj-;
R3 is H- or CH30 -;
1 0 0
Ri ~s H-, CH:3-, or CH~C-, and
R3 plus R~ is -O-CH2-O-
Speci.fic examples of ethylencia:lly unsaturated aromatic
compounds suitable for the purposes of this invention
include styrene, alpha-methylstyrene, 4-methyl styrene,
stilbene, 4-acetoxyst:ilbene (used to p~epare a hydrolized
4-hyclroxystil.bene/maleic anhydride polymer), eugenol.,
isoeugenol, 4-allylphenol, safrole, mix:tures of the same,
~0 and t:he like. From the standpoint of cost-effectiveness,
a co-polymer prepared from styrene and maleic anhydride at
a 1:1 molar ratio is preferred. The hydrolyzed polymers
can have molecular we:ights ~number average) in the range
between about 500 and 4000, preferably between about 800
~5 and 2000. They are readily soluble, even at high
concentrations, in water at neutral to alkal.ine pH;
increasing dilution is needed at a pH kelow 6. They are
also soluble in lower alcohols, such as methanol, a.nd are
somewhat soluble in acetic acid.
The compositions of this invention can be
appli.ed to dyed or undyed textile substrates. They can be
appli.ed to such substrates in the abse~ce of. a
polyfluoroorganic oil--, water-, and/or soil-repellent
materials. Alternatively, such a polyfluoroorganic
~5 material can be applied to the textile substrate before or
after application of the composition of this
'~ i
134~028
invention to it. The compositions of this invention
can be applied to textile substrates in a variety of
ways, e.g. during conventional beck and continuous
dyeing procedures. The quantities of the polymers of
this invention which are applied to the textile
substrate are amounts effective in imparting stain-
resistance to the substrate. The amounts can be varied
widely; in general, between about 0.1 and 2% by weight
of them based on the weight of the textile substrate,
usually about 0.6% by weight or less. The compositions
can be applied, as is common in the art, at pHs ranging
between 4 and 5. However, more effective exhaust
deposition can be obtained at a pH as low as 2. More
effective stainblocking is obtained if the compositions
of this invention are applied to the textile substrate
at higher temperatures. For example, at pH 2, 170-F is
preferred, and 200-F is preferred at pH 5. However,
stainblocking can be obtained when application is
effected at room temperature, or even at that of cold
tap water (10-15-C).
In another embodiment of this invention, the
compositions of this invention are applied in-place to
carpeting which has already been installed in a
dwelling place, office or other locale. The
compositions can be applied as a simple aqueous
preparation or in the form of an aqueous shampoo
preparation with or without one or more polyfluoro-
organic oil-, water-, and/or soil-repellent materials.
They may be applied at the levels described above, at
temperatures described, and at a pH between about 1 and
12, preferably between about 2 and 9.
The following Examples are illustrative of
the invention. Unless otherwise indicated, all p~rts
and percentages are by weight and temperatures in the
Ei:amples 3nd Tests are in degrees Celsius, and st~in-
1 340~8
--10--
resistance and yellowing were measured by thetechniques described in the text which precedes the
Examples.
E~haust Application of Stain-Resists to CarPetinq
Launder-O-Meter Method
Exhaust application of stain-resists to
carpeting is carried out in a Launder-O-Meter automated
dyeing machine. One carpet piece is contained in each
of several (up to twenty) stainless steel, screw-cap
canisters. The canisters are held in a rack that
rotates in a water bath whose temperature is
automatically controlled for rate of heating, time at
temperature and cooling. For a typical application
bath, one uses a 20 to 1 liquor to goods ratio with 2.5
weisht % of the stain-resistant composition. The
stain-resistant compositions can be applied at pH 2 or
p~ c,. At pH 2, an excess of sulfamic acid is used. At
pH 5, an excess of ammonium sulfate is used, as well as
3g/I. of magnesium sulfate and lg/L of an alkyl aryl
sulfonate (Alkanol~ ND) or a suitable leveling agent.
After the bath is made up, a solution of the stain-
resist composition is added to the Launder-o-Meter
canister. The carpet sample to be treated is then
placed in the canister, tufted side out, the size of
the carpet sample, relative to the size of the
canister, being such that the no port:ion of the sample
touches another portion of the sample. The canisters
are placed in the Launder-O-Meter and the water bath
temperature is held at 110-F for 5 minutes. The
temperature of the water bath is then raised to the
desired temperature for application of the stain-resist
composition. For application at pH ~, the temperatu~e
of the water bat~. is raised to 170-F + 5-F, and for
application .-,t pH 5, the temperature of the water ba h
* denotes trade marlc
--10--
1~4002~
is raised to 200-F + 5~F. After the bath water reaches
the desired temperature, it is held there for 20 min.
and then cooled to 100~F. The treated carpet sample is
removed from the canister and rinsed by cqueezing in
deionized water at room temperature. Three successive
rinses in fresh deionized water are given, each rinse
being at 40 volumes of water per volume of sample. The
rinsed carpet sample is centrifuged to remove excess
liquid and dried at 200~F. in a forced draft oven for
30 minutes. The dry carpet sample can then be tested
by use of the tests described below.
Stain Test
The Stain Test is used to measure the extent
to which carpeting is stained by a commercial beverage
composition which contains FD&C Red Dye No. 40 (an acid
dye). The staining liquid, if sold commercially as a
liquid, is used as is. Usually the commercial product
is in the form of a solid. In that event, the beverage
preparation, in dry, solid form, is dissolved in
deionized water so as to provide 0.1 g of FD&C Red Dye
No. 40 per liter of water. Sufficient wetting agent
(Du Pont Merpol~SE liquid nonionic ethylene oxide
condensate) is added to the dye solution to provide 0.5
g of the wetting agent per liter of dye solution. The
test sample is DuPont type 1150 Nylon 6,6 (white);
Superba heatset, mock dyed level loop carpet, 3/8 inch
pile height, 30 ounces per yard, 1/10 inch gauge, 10
stitches per inch, woven polypropylene primary backing.
~he test sample is wetted completely with
water, and excess water is removed by centrifuging.
The damp sample is placed tufted face down in a pan and
covered with ten times its face weiqht of ~tain fluid.
Entrained air is expelled from the sample by squeezing
or pressinc3. The sample is turned over and again t!~e
air is expelled. The sample is then returned to a ~ace
1 34D~28
-12-
down position, and the pan is covere~ for storage for
desired test period,, namely 30 minutes or 24 hours.
The stored stain sample is rinsed in running cool water
until no more stain is visually detectable in the rinse
water. The rinsed sample is extracted in a centrifuge
and dried at 200 degrees F. Stainin~ is evaluated with
the Minolta Chroma Meter tristimulus color analyzer in
the L*A*B Difference Mode with the target sample set
for the unstained carpet. The ~a~ value is a measure
of redness, with a value of 43 equal to that obtained
on an untreated carpet.
W YELLOWING TEST
The light-fastness of carpet samples treated
with a stainblocker is determined by exposing the
treated samples to 1~ light for 20 Hours. A sample
piece of carpet that has been treated with a stain-
blocker is placed in a box containing its hinged top a
standard fluorescent fixture fitted with two forty watt
lamps. Centered under the pair of lamps in the bottom
of the box is a sliding tray having a 3 inch x 40 inch
recess for holding carpet specimens. The depth of the
recess is such that the distance fro~ the carpet face
to the plane defined by the lamp surfaces is 1 inch.
The current to the lamp is controlled by a timer so
that a twenty-hour exposure can be o~tained
automatically. After the twenty-hour exposure, the
reflectance of CIE White Light Source C from the carpet
is compared with the reflectance fro~ an unexposed
sample and the CIELAB delta ~b~ noted. Delta ~bn is a
measure of the yellow component of white light. A
Minolta Chro~a Meter model CR-llO reflectance meter is
used to make the measurements and to calculate delta
"b~ automatically from stored da~a on the unexposed
sample. The value of ~b" is reported as the ~easure of
* denotes trade mark
-12-
~.
1 34~
-13-
yellowing with increasing positive values of "b"
corresponding to increased degrees of yellowing.
The Minolta Chroma Meter is used in the
Hunter L*a*b color-deviation measuring mode [Richard
Hunter, ~Photoelectric Colorimetry with Three Filters,"
J. Opt. Soc. Am., 32, 509-538 (1942)]. In the
measuring mode, the instrument measures the color
differences between a ~target~ color, whose tristimulus
color values have been entered into the microprocessor
lo as a reference, and the sample color presented to the
measuring head of the instrument. In examining carpet
samples for yellowing and for FD&C Red Dye No. 40
staining, the ~target~ color entered is that of the
carpet before yellowing or staining. The color
reflectance of the yellowed or stained carpet is then
measured with the instrument and reported as:
~E, the total color difference, *L, the
lightness value,
*a, the redness value, if positive, or
greenness, if negative, and
*b, the yellowness value, if positive, or
blueness, if negative.
EXAMPT-~ 1
Hydrolysis of Styrene/Maleic Anhydride Polymer (HSMA~
In a 7 gallon paste pail, 4800 gms of a 1/1
molar styrene/maleic anhydride copolymer having a
number average molecular weight of 1600 (SMA~1000 from
Sartomer) were stirred into 3000 gms deionized water to
give a smooth slurry. It dispersed well (no exotherm)
in about 15 minutes. Then over about 1 hour, 5400 gms
of 30% NaOH were added. The reactor was cooled during
addition to maintain temperature in the 30-40-C rar.ge.
If the tem~erature went over about 40-C, addition o~
caustic solution was stopped. (Above 45 C, the po ~mer
-14- 134002~
may melt and coagulate into large sticky globs which
are very slow to hydrolyze.) After all of the NaOH
solution has been added, the reaction mass was stirred
for 15 minutes, then the reactor was heated to 70 C and
stirred for 3 hours. Heating was stopped, and 2800 gms
of deionized water was added with stirring, followed by
cooling to 50-C. A light yellow, slightly viscous,
clear alkaline solution of a polysodium salt of
styrene/maleic acid copolymer was obtained.
The product solution thus obtained was
applied to nylon carpet at 2-lJ2 percent on weight of
fiber in a simulated bec~ dyeing apparatus. The dried
carpet was tested by saturating it with a solution of
FD&C Red Dye No. 40 and letting it stand for 1/2 hour
at room temperature (Stain Test described above). It
was then rinsed with cold water. The treated carpet
showed no evidence of staining while an untreated
control was deeply stained red. In a similar test the
carpet was allowed to stand for 24 hours in the acid
dye solution; on rinsing, the carpet treated with the
above product showed a noticeable pink stain while the
untreated carpet was again stained a deep red. When
the 24 hr. test was repeated using an 80:20 blend of
the above product with the phenolic stain resist,
SPFCAD (defined in Example 2), the treated carpet was
stain-free while the untreated carpet was stained a
deep red. Carpets treated with the product obtained
from Example 1 did not yellow on 24 hr. exposure to W
light (UV Yellowing Test described above). Carpets
treated ~ith the 80:20 blend yellowed slightly while
carpets treated with similar levels of the phenolic
stain resist by itself yello~ed noticeably.
1340~28
- 15 -
EXAMPLE 2
The following shampoo compos3tior was applied in
place to 6,6-~lylon carpets:
Inqredient
Water 42.1
SMAC 9.3
Na C~2 S0416.5
PGME 9.1
DPM 9.1
Fluorsurfactant 3.9
SPFCAD 10.0
Total 100.0
Definitions
SMAC: 30 parts sytrene/maleic anhyGride copolymer
(ARCO SMA'~1000 resin), 36.2 parts water, 33.8 parts 30%
NaOH combined and heated to hydrolyze the resin per the
procedure described in Example 1.
Na C12 S04 30% aqueous sodium lauryl su]fate.
PGME: Propylene glycol monomethyl ether
DPM: Dipropylene glycol monomethyl ether
Fluorosurfactant: A mixture of Li fl~oroalkyl mercapto
propionate and diethanolammonium fluoralkyl phosphate in a
1.0:1.1 ratio.
SPFCAD: in parts by weight, 29 parts of a sulfonated
phenol-formaldehyde condensate (as describecl in Example 9
of said Liss et al. Patent), 44.5 parts of ethylene
glycol, 21 parts of water, 4 parts of inorganic salts and
1.5 parts of ~cetic acid.
.X~
13400~
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Performance
The shampoo composition was ciluted 19:1 with H2O
and applied with a Tornado* extraction carpet cleaner (3
passes) to T84~, 2-ply, Superba* heats~t BCE Saxony*
carpet dyed to a light beige (representative of
residential carpet). Visual inspectior showed little or
no yellowing. The Stain Test was run cn the~ shampooed
carpet, giving a Stain Ratlng of 5 wher measured thirty
minutes after application of the Red D~e Nc. 40, and a
Stain Rating of 4-5 when measured twenty-four hours after
application. In both cases, an untreated control gave a
Stain Rating of 0. Uniformity of stair removal after
shampooing was excellent. Stain Rating: 5 =- unstained, 4
= barely visible stain, 3 = light pink stain, 2 = pink
stain, 1 = pink to red stain, 0 = red stain like untreated
control.
EXAMPLES 3-5
Additional blends of 80 parts by weight of
hydrolyzed styrene/maleic anhydride compolymer (SMA) and
20 parts by weight of various sulfonated phenol-
formaldehyde -ondensates. The SMA polymer had been
hydrolyzed in essentially the same manner as in EXAMPLE 1.
The sulfonated phenol-formaldehyde condensate of EXAMPLE 3
had been prepared as described in Exam~le 9 of said Liss
and Beck patent; that of EXAMPLE 4 was the commercial
product MESITOL NBS, and that of EXAMPIE 5 was purified as
described in ~he aforesaid Marshall patent. When tested
for stain blocking as described above (at 4.5~ on the
weight of the fiber), the blends gave Yesult:s similar to
those described above.
* denotes trade mark
.XI ,.
-17- 1340d2~
ExAMpLEs 6-8
The procedure of EXAMPLES 3-5 was repeated
with 90:10 SMA:condensate blends, giving similar stain
blocking test results.
EXAMPLE 9
A blend were prepared from 20 parts by weight
of the sulfonated phenol-formaldehyde condensate of
Example 9 of the Liss and Beck application and 80 parts
by weight of a hydrolized styrene/stilbene/maleic
anhydride polymer, mol ratio of 0.75J0.25/l.0 (prepared
substantially as described in EXAMPLE 7 of said
Fitzgerald, Rao, Vinod, Henry and Prowse patent
application). When tested for stain blocking in the
aforesaid simulated Beck dying operation, the blend
exhibited stain blocking properties.
EXAMPLES lO & 11
Two blends were prepared, each from 20 parts
by weight of the condensate of Example 9 of the Liss
and Beck application and 80 parts by weight of a
hydrolized 4-hydroxystilbene/styrene/maleic anhydride
terpolymer. In one of the blends, the terpolymer mol
ratio was 0.25/0.75/1.0, and in the other one, the mol
ratio was 0.5/0.5/1.0 (prepared substantially as
described in EXAMPLES 14 and 16 respectively of said
Fitzgerald, Rao, Vinod, Henry and Pro~se patent
application). When tested for stain blocking as described
above, the bl~nds exhibited stain blocking properties.
,,~
~r ~
