Poly(ethylene oxide) compositions with controlled solubility characteristics

Solid cake compositions comprising poly(ethylene oxide), surfactant and water-soluble salt. The compositions have controlled solubility characteristics, thereby reducing the tendency of the resin to form a gel when the cake is contacted with water. The cakes are useful in dispensers which are employed in the flush tank of a toilet to automatically dispense chemicals to the flush water.

TECHNICAL FIELD 
The present invention relates to cake compositions which are useful for the 
treatment of the flush water of toilets in order to reduce the tendency of 
such flush water to produce aerosolization during the flushing of the 
toilet. The compositions comprise a poly(ethyleneoxide)resin, a surfactant 
and a water-soluble salt, and are formulated so as to avoid excessive 
amounts of gelling when used in certain types of dispensing means for 
automatic dispensing of chemicals into the toilet flush tank. 
BACKGROUND ART 
The reduction of aerosolization produced by the flushing of toilets is 
desirable in order to reduce the possibility of airborne transmission of 
disease organisms from the toilet wastewater. In the application of 
McCune, U.S. Ser. No. 959,405, filed Nov. 9, 1978, and incorporated by 
reference herein, it is disclosed that the aerosolization of wastewater 
from flushing toilets can be significantly reduced by the presence of low 
levels (1-30 ppm) of high molecular weight poly(ethylene oxide) resins in 
the wastewater. 
In treating toilet flush water with chemicals in order to produce desirable 
effects such as bowl cleaning, disinfection, deodorization, aerosol 
reduction etc., it is desirable that the chemicals be dispensed into the 
flush water automatically each time the toilet is flushed. The prior art 
discloses numerous devices which have been designed for this purpose. 
Exemplary of such devices are those disclosed in U.S. Pat. Nos. 3,831,205, 
issued Aug. 27, 1974 to Foley, 3,341,074 issued Sept. 12, 1967 to 
Pannutti, 3,504,384 issued Apr. 7, 1970 to Radley et al, 2,688,754 Sept. 
14, 1954 to Willits et al. and 4,036,407, issued July 19, 1977 to Slone. 
Particularly desirable devices are those wherein the chemical composition 
is in the device in the form of a solid cake composition. In this type of 
device a measured amount of water enters the device during one flush cycle 
and remains in contact with the cake composition between flushes, thereby 
forming a concentrated solution of the composition which is dispensed into 
the flush water during the next flush. Obvious advantages of such devices 
are that the chemical composition can be packaged and shipped in more 
concentrated form than an aqueous solution of the chemicals, and the 
problems of liquid spillage resulting from breakage of the dispensers 
during shipment or handling is eliminated. Especially preferred devices 
for automatic dispensing of chemicals from solid cake compositions into 
the toilet are those described in U.S. Pat. No. 4,171,546 of Dirksing, 
issued Oct. 23, 1979, U.S. Pat. No. 4,208,747 of Dirksing, issued June 24, 
1980, and U.S. Pat. No. 4,186,856 of Dirksing, issued Feb. 5, 1980, all of 
said patents being incorporated herein by reference. 
It has been found that when solid cake compositions comprising high 
molecular weight poly(ethylene oxide) resins (i.e. molecular weights of 
from about 500,000 to about 7,000,000) are utilized in automatic 
dispensers, the resin forms a thick gel when exposed to the limited volume 
of water within the dispenser, thereby retarding or even completely 
blocking the subsequent flow of dissolved materials out of the dispenser 
and into the flush water. 
It is an object of the present invention to provide solid cake compositions 
comprising poly(ethylene oxide)resins, which compositions are suitable for 
use in dispensers for automatically dispensing chemicals into the toilet. 
It is a further object of the present invention to provide solid cake 
compositions comprising poly(ethylene oxide) resins which compositions 
have a reduced tendency to form gels when exposed to water. 
SUMMARY OF THE INVENTION 
The present invention relates to solid cake compositions having controlled 
solubility characteristics. 
The compositions comprise: 
(1) from about 1% to about 20% of a poly(ethyleneoxide) resin having a 
molecular weight from about 500,000 to about 7,000,000; 
(2) an alkali metal sulfate salt or mixture of said salts in a weight ratio 
of at least about 2.5:1 of alkali metal sulfate salt to resin; and 
(3) an organic surfactant in a weight ratio of surfactant to alkali metal 
sulfate salt of from about 0.5:1 to about 2:1. 
DISCLOSURE OF INVENTION 
According to the present invention it has been found that by combining 
poly(ethylene oxide) resins (hereinafter also referred to as PEO resins) 
with certain types of surfactants and water-soluble salts in certain 
proportions, compositions are obtained wherein the tendency of the resin 
to gel upon exposure to water is greatly reduced, thereby facilitating the 
dispensing of said resins into toilet flush water from automatic 
dispensing devices. 
The compositions of the present invention are in the form of solid cakes 
and comprise: 
(1) From about 1% to about 20% (preferably 5% to 12%) of a poly(ethylene 
oxide) resin having a molecular weight of from about 500,000 to about 
7,000,000; 
(2) An alkali metal sulfate salt in a weight ratio of at least from 2.5:1 
of said salt to said resin; 
(3) An organic surfactant in a weight ratio of surfactant to alkali metal 
sulfate salt (Component 2) of from about 0.5:1 to about 2.1. 
All percentages and ratios recited herein are "by weight" unless otherwise 
specified. 
The resin in the compositions herein when present in the water in the 
toilet bowl at levels of at least about 0.1 ppm or more, preferably 
greater than about 1 ppm, and most preferably about 4 to 15 ppm, 
significantly reduces the tendency for aerosol formation during the 
flushing of the toilet. The alkali metal sulfate salt reduces gelling of 
the resin in the dispensing device from which the resin is advantageously 
dispensed into the toilet tank flush water. it is believed that the alkali 
metal sulfate operates by suppressing the solubility of the resin, thereby 
also suppressing gelation of dissolved resin. The surfactant is believed 
to provide controlled solubilization of the salt-insolubilized resin. When 
the resin is combined with the alkali metal sulfate and surfactant in the 
manner described herein, a composition is obtained which provides 
sufficient solubilization of the resin to produce the required 
concentration of resin in solution for dispensing into the flush water, 
and at the same time avoids excessive gelling of the resin, which can clog 
the dispenser used for automatically dispensing the solution of resin into 
the flush water. 
The poly(ethylene oxide) resins of the present invention are polymers of 
ethylene oxide having average molecular weights of from about 500,000 to 
7,000,000. The preferred molecular weight range is from about 1,000,000, 
to about 7,000,000. These polymeric resins are commercially available 
under the trade name Polyox.sup.R from Union Carbide Corporation. They can 
be prepared by the polymerization of ethylene oxide, utilizing an alkaline 
earth metal oxide as catalyst. The amount of PEO resin in the compositions 
herein can be from about 5% to about 20%, preferably from about 8% to 12%. 
The alkali metal salts used in the present invention are the sulfate salts 
of the Group 1A metals of the Periodic Table. The preferred sulfates are 
sodium and potassium sulfate. The most preferred salt is sodium sulfate. 
Mixtures of alkali metal sulfate salts can be used. 
The ratio of alkali metal sulfate salt to resin in the compositions herein 
is preferably from about 2.5:1 to about 6:1, most preferably about 3.5:1. 
Ratios in excess of 10:1 can be used. Excessive amounts of salt, however, 
can adversely affect the ability of the surfactant to carry out its 
solubilizing and dispersing function. Accordingly the amount of alkali 
metal sulfate salt must also be chosen in relation to the amount of 
surfactant in the formula. Preferably the amount of alkali metal salt will 
not exceed twice the amount of surfactant. In general, the ratio of 
surfactant to alkali metal salt will be from about 0.5 to 1 to 2:1. 
The Surfactant 
The third essential component of the composition herein is an organic 
surfactant. Anionic, nonionic, ampholytic, zwitterionic or cationic 
surfactants can be used. The surfactant or surfactant mixture should be 
solid at ambient temperature, i.e. temperatures up to about 100.degree. F. 
Anionics and nonionics and mixtures thereof are preferred. Anionics are 
the most preferred. 
The anionic surfactants can be broadly described as the water-soluble 
salts, particularly the alkali metal salts, of organic sulfuric acid 
reaction products having in their molecular structure an alkyl or alkaryl 
radical containing from about 8 to about 22 carbon atoms and a radical 
selected from the group consisting of sulfonic acid and sulfuric acid 
ester radicals. (Included in the term alkyl is the alkyl portion of higher 
acyl radicals.) Important examples of the anionic surfactants which can be 
employed in the practice of the present invention are the sodium or 
potassium alkyl sulfates, especially those obtained by sulfating the 
higher alcohols (C.sub.8 -C.sub.18 carbon atoms) produced by reducing the 
glycerides of tallow or coconut oil; sodium or potassium alkyl benzene 
sulfonates, in which the alkyl group contains from about 9 to about 15 
carbon atoms, (the alkyl radical can be a straight or branched aliphatic 
chain); sodium or potassium alkyl naphthalene sulfonates containing one or 
two alkyl groups of 1 to about 6 carbon atoms each; paraffin sulfonate 
surfactants having the general formula RSO.sub.3 M, wherein R is a primary 
or secondary alkyl group containing from about 8 to about 22 carbon atoms 
(preferably 10 to 18 carbon atoms) and M is an alkali metal, e.g., sodium 
or potassium; sodium alkyl glyceryl ether sulfonates, especially those 
ethers of the higher alcohols derived from tallow and coconut oil; sodium 
coconut oil fatty acid monoglyceride sulfates and sulfonates; sodium or 
potassium salts of sulfuric acid esters of the reaction product of one 
mole of a higher fatty alcohol (e.g., tallow or coconut oil alcohols) and 
about 1 to 10 moles of ethylene oxide; sodium or potassium salts of alkyl 
phenol ethylene oxide ether sulfates with about 1 to about 10 units of 
ethylene oxide per molecule and in which the alkyl radicals contain from 
about 8 to about 12 carbon atoms; the reaction products of fatty acids 
esterified with isethionic acid and neutralized with sodium hydroxide 
where, for example, the fatty acids are derived from coconut oil; sodium 
or potassium salts of fatty acid amides of a methyl tauride in which the 
fatty acids, for example, are derived from coconut oil, and sodium or 
potassium .beta.-acetoxy- or .beta.-acetamido-alkane-sulfonates where the 
alkane has from 8 to 22 carbon atoms. 
Nonionic surfactants which can be used in practicing the present invention 
can be of three basic types--the alkylene oxide condensates, the amides 
and the semi-polar nonionics. 
The alkylene oxide condensates are broadly defined as compounds produced by 
the condensation of alkylene oxide groups (hydrophilic in nature) with an 
organic hydrophobic compound, which can be aliphatic or alkyl aromatic in 
nature. The length of the hydrophilic or polyoxyalkylene radical which is 
condensed with any particular hydrophobic group can be readily adjusted to 
yield a water-soluble-compound having the desired degree of balance 
between hydrophilic and hydrophobic elements. 
Examples of such alkylene oxide condensates include: 
1. The condensation products of aliphatic alcohols with ethylene oxide. The 
alkyl chain of the aliphatic alcohol can either be straight or branched 
and generally contains from about 8 to about 22 carbon atoms. Examples of 
such ethoxylated alcohols include the condensation product of about 6 
moles of ethylene oxide with 1 mole of tridecanol, myristyl alcohol 
condensed with about 10 mols of ethylene oxide per mole of myristyl 
alcohol, the condensation product of ethylene oxide with coconut fatty 
alcohol wherein the coconut alcohol is a mixture of fatty alcohols with 
alkyl chains varying from 10 to 14 carbon atoms and wherein the condensate 
contains about 6 moles of ethylene oxide per mole of alcohol, and the 
condensation product of about 9 moles of ethylene oxide with the 
abovedescribed coconut alcohol. Examples of commercially available 
nonionic surfactants of this type include Tergitol 15-S-9 marketed by the 
Union Carbide Corporation, Neodol 23-6.5 marketed by the Shell Chemical 
Company and Kyro EOB marketed by The Procter & Gamble Company. 
2. The polyethylene oxide condensates of alkyl phenols. These compounds 
include the condensation products of alkyl phenols having an alkyl group 
containing from about 6 to about 12 carbon atoms in either a straight 
chain or branched chain configuration, with ethylene oxide, the said 
ethylene oxide being present in amounts equal to 5 to 25 moles of ethylene 
oxide per mole of alkyl phenol. The alkyl substituent in such compounds 
can be derived, for example, from polymerized propylene, diisobutylene, 
octene, or nonene. Examples of compounds of this type include nonyl phenol 
condensed with about 9.5 moles of ethylene oxide per mole of nonyl phenol, 
dodecyl phenol condensed with about 12 moles of ethylene oxide per mole of 
phenol, dinonyl phenol condensed with about 15 moles of ethylene oxide per 
mole of phenol, di-isooctylphenol condensed with about 15 moles of 
ethylene oxide per mole of phenol. Commercially available nonionic 
surfactants of this type include Igepal CO-610 marketed by the GAF 
Corporation; and Triton X-45, X-114, X-100 and X-102, all marketed by the 
Rohm and Haas Company. 
3. The condensation products of ethylene oxide with a hydrophobic base 
formed by the condensation of propylene oxide with propylene glycol. The 
hydrophobic portion of these compounds has a molecular weight of from 
about 1500 to 1800 and of course exhibits water insolubility. The addition 
of polyoxyethlene moieties of this hydrophobic portion tends to increase 
the water-solubility of the molecule. Examples of compounds of this type 
include certain of the commercially available Pluronic surfactants 
marketed by the Wyandotte Chemicals Corporation. 
4. The condensation products of ethylene oxide with the product resulting 
from the reaction of propylene oxide and ethylene diamine. The hydrophobic 
base of these products consists of the reaction product of ethylene 
diamine and excess propylene oxide, said base having a molecular weight of 
from about 2500 to about 3000. This base is condensed with ethylene oxide 
to the extent that the condensation products contains from about 40% to 
about 80% by weight of polyoxyethylene and has a molecular weight of from 
about 5,000 to about 11,000. Examples of this type of nonionic surfactant 
include certain of the commercially available Tetronic compounds marketed 
by the Wyandotte Chemicals Corporation. 
Examples of the amide type of nonionic surfactants include the ammonia, 
monoethanol and diethanol amides of fatty acids having an acyl moiety of 
from about 8 to about 18 carbon atoms. These acyl moieties are normally 
derived from naturally occurring glycerides, e.g., coconut oil, palm oil, 
soybean oil and tallow, but can be derived synthetically, e.g., by the 
oxidation of petroleum, or by hydrogenation of carbon monoxide by the 
Fischer-Tropsch process. 
Examples of the semi-polar type of nonionic surfactants are the amine 
oxides, phosphine oxides and sulfoxides. These materials are described 
more fully in U.S. Pat. No. 3,819,528, Berry, issued June 25, 1974, and 
incorporated herein by reference. 
Many nonionic surfactants are liquids at ambient temperatures, thus it may 
be necessary to combine them with solid surfactants in order to formulate 
them into the solid cake compositions herein. 
Ampholytic surfactants which can be used in practicing the present 
invention can be broadly described as derivatives of aliphatic amines 
which contain a long chain of about 8 to about 18 carbon atoms and an 
anionic water-solubilizing group, e.g., carboxy, sulfo and sulfato. 
Examples of compounds falling within this definition are 
sodium-3-dodecylamino-propionate, sodium-3-dodecylamino propane sulfonate, 
and dodecyl dimethylammonium hexanoate. 
Zwitterionic surfactants which can be used in practicing the present 
invention are broadly described as internally-neutralized derivatives of 
aliphatic quaternary ammonium and phosphonium and tertiary sulfonium 
compounds, in which the aliphatic radical can be straight chain or 
branched, and wherein one of the aliphatic substituents contains from 
about 8 to about 18 carbon atoms and one contains an anionic 
water-solubilizing group, e.g., carboxy, sulfo, sulfato, phosphato, or 
phosphono. 
Cationic surfactants which can be used in practicing the present invention 
include stearyl dimethyl benzyl ammonium chloride, coconut dimethyl benzyl 
ammonium chloride, cetyl pyridinium chloride and cetyl trimethyl ammonium 
chloride. 
Particularly preferred surfactants for use herein are sodium and potassium 
alkyl naphthalene sulfonates having one or two alkyl groups containing 
from 1 to about 6 carbons each, and paraffin sulfonates having the formula 
RSO.sub.3 M, wherein R is a primary or secondary alkyl group containing 
from about 8 to about 22 carbon atoms (preferably about 12 carbon atoms), 
and M is an alkali metal. 
The use of naphthalene sulfonates in the formulation of cake compositions 
of the type encompassed by the present invention is described in the 
concurrently filed application of Choy, entitled "SURFACTANT CAKE 
COMPOSITIONS", U.S. Ser. No. 154,000 filed May 28, 1980, now U.S. Pat. No. 
4,278,571, issued July 14, 1981, by reference herein. 
Optional Materials 
Various optional materials may be included in the compositions herein. 
Dyes may be included at levels of from about 2.5% to 10%. Examples of 
suitable dyes are Alizarine Light Blue B (X.I. 63010), Carta Blue VP (C.I. 
24401), Acid Green 2G (C.I. 42085), Astragon Green D (C.I. 42040), 
Supranol Cyanine 7B (C.I. 42675), Maxilon Blue 3RL (C.I. Basic Blue 80), 
Drimarine Blue Z-RL (C.I. reactive Blue 17), Alizarine Light Blue H-RL 
(C.I. Acid Blue 182), FD & C Blue No. 1 and FD & C Green No. 3 (See the 
applications of Kitko, U.S. Ser. No. 972,318 filed Dec. 22, 1978 and U.S. 
Ser. No. 915,027, filed June 12, 1978, both incorporated by reference 
herein. C.I. refers to The Color Index. 
Partially hydrolyzed polyacrylamides or copolymers of ethylene and maleic 
anhydride at levels of from about 5% to about 30% are desirable components 
of the compositions herein when said compositions are used in conjunction 
with compositions which dispense hypochlorite bleach into the toilet flush 
water. These polymers have been found to reduce the tendency of Mn (II) 
ions in the water to become oxidized to Mn (IV) by hypochlorite and stain 
in the toilet bowl. Exemplary hydrolyzed polyacrylamides are those sold 
under the names P-35 and P-70 by American Cyanamid Company, Wayne, New 
Jersey. P-35 has a molecular weight of about 7000 and P-70 has a molecular 
weight of about 2000. Both are about 80% hydrolyzed. Exemplary copolymers 
of ethylene and maleic anhydride are EMA-21 and EMA-31, which are 
available from Monsanto Co., St. Louis, Mo. The use of these materials in 
toilet bowl cleaning compositions is described in U.S. Ser. No. 028,612, 
Kurtz, filed Apr. 9, 1979; U.S. Ser. No. 028,613, Callicott, filed Apr. 9, 
1979; and U.S. Ser. No. 028,293, Callicott, filed Apr. 9, 1979, now 
abandoned in favor of U.S. Ser. No. 234,535 filed Feb. 17, 1981, all 
incorporated by reference herein. 
Alkali metal bromide (e.g. sodium bromide) is a particularly desirable 
component of the compositions herein when said compositions are used in 
conjunction with compositions which dispense hypochlorite bleach into the 
flush water. The bromide ion acts as an activator, to enhance the 
bleaching and sanitizing performance of the hypochlorite when the two are 
mixed together in the flush water. Generally the bromide salt will 
comprise from about 1% to 4% of the compositions herein. 
Perfumes can be incorporated into the compositions herein at levels of from 
about 0.5% to about 20%, preferably from about 2% to 11%. As described in 
U.S. Pat. No. 4,246,129, Kacher, issued Jan. 20, 1981 (incorporated by 
reference herein), certain perfume materials can perform the added 
function of reducing the solubility of anionic sulfonate and sulfate 
surfactants used in the compositions herein, if this is desirable. 
Examples of such perfume materials are isobornyl acetate, myrtenyl acetate 
and fenchyl acetate. 
Stabilizers for the PEO resins can be incorporated into the compositions 
herein to prevent degradation of the resin to lower molecular weight 
species. Such degradation is often caused by oxidation which is catalyzed 
by trace amounts of transition metal ions (e.g. iron or chromium) which 
are brought into the composition as contaminants in other materials such 
as the dyes, surfactants, etc. A preferred stabilizer is thiourea at a 
level of from about 1% to about 20% based on the weight of the resin. 
Another desirable optional ingredient for the compositions herein is a 
fluorinated polyoxyethylene ethanol surfactant. An example of this type of 
material is Fluorad FC-170, sold by 3M Company, Minneapolis, Minn. 55101. 
The amount of fluorinated polyoxyethylene ethanol surfactant should be 
from about one tenth to about one thirtieth the amount of PEO resin in the 
composition. These fluorinated surfactants enhance the aerosol suppression 
performance of the PEO resins. 
Dispensing Means 
Dispensing means which can be used to dispense compositions of the present 
invention into the toilet flush water are exemplified by those described 
in U.S. Pat. No. 3,831,205, 3,341,074, 3,504,384, 2,688,754, 4,036,407, 
4,171,546, 4,208,747 and 4,186,856. A particularly advantageous dispensing 
means for use with the compositions herein is described in the 
concurrently filed application of Choy entitled "PASSIVE DOSING DISPENSER 
EXHIBITING IMPROVED RESISTANCE TO CLOGGING," U.S. Ser. No. 153,997, filed 
May 28, 1980, incorporated by reference herein. 
Although the cake compositions herein have a low tendency toward gel 
formation in dispensers designed for use in flush toilet tanks, they 
nevertheless do form some gel. Accordingly, it is preferable that they be 
used in a dispensing device which is especially designed to minimize any 
adverse effects on dispensing which may accompany even small amounts of 
gel formation by the compositions herein. The above-noted dispenser of 
Choy is such a device. 
Composition Manufacture 
The manufacture of solid cakes of the compositions herein is well within 
the capability of persons of ordinary skill in the tableting art. The 
composition components are mixed to form a homogeneous granular mass and 
this mass is formed into a cake of the desired dimensions by use of 
conventional stamping or pressing equipment. 
The invention herein will be illustrated by the following examples.

EXAMPLE I 
This example illustrates the ability of sodium sulfate, at appropriate 
sodium sulfate:resin ratios, to reduce the gelling of the resin when in 
contact with water. An objective measure of gelling is the amount of water 
absorbed by the resin. 
Test Procedure: 
(1) 5 grams of Polyox C, a granular poly (ethylene oxide) resin having a 
molecular weight of approximately 5.times.10.sup.6, was weighed and mixed 
in a jar with the appropriate amount of sodium sulfate to give Na.sub.2 
SO.sub.4 :resin weight ratios of 0:10, 2:10, 5:10, 10:10, 25:10 and 50:10, 
respectively. 
(2) Each of the mixtures was placed in a tabletting cylinder of 11/8 inch 
inside diameter and compressed to a pressure of 5000 pounds per square 
inch with a manually operated hydraulic press (Carver Press--12 ton--Model 
C) 
(3) The tablets were each immersed in 100 ml distilled water in a 150 ml 
beaker at room temperature (70.degree.-75.degree. F). for 72 hours. The 
gross weight of beaker plus water, before introduction of the tablet and 
after the tablet was removed, was recorded. The amount of water absorbed 
by the tablet was determined by difference. The amount of water absorbed 
is a measure of the amount of gelling which occurred. 
The test was run on two different occasions, with three replicates each 
time the test was run. 
The results are shown in the following table. Results are expressed as 
grams of water absorbed by the tablet. 
TABLE I 
______________________________________ 
A B C D E F 
______________________________________ 
Polyox C 5 g 5 g 5 g 5 g 5 g 5 g 
Na.sub.2 SO.sub.4 
0 1 2.5 5 12.5 25 
Test 1 
Rep. 1 43 g 44 g 42 g 31 g 26 g 28 g 
Rep. 2 42 44 42 45 43 21 
Rep. 3 42 45 41 44 27 29 
Avg. 42 44 42 40 32 26 
Test 2 
Rep. 1 53 53 60 57 45 30 
Rep. 2 48 51 47 56 47 35 
Rep. 3 53 54 51 53 46 36 
Avg. 51 53 53 55 46 34 
______________________________________ 
These data show a clear breakpoint in water absorption at about a 2.5:1 
ratio of sodium sulfate:resin. 
EXAMPLE II 
A composition of the present invention was prepared according to the 
following procedure. 
(1) All dry ingredients (i.e. all ingredients except the perfume and 
Fluorad FC-170) were weighed, placed in a Waring Blender, and mixed in the 
blender for 5-10 minutes to form a homogeneous mixture. 
(2) The FC-170 and perfume were mixed together and added to the mixture in 
the blender and mixing was continued until the total mixture was judged to 
be homogeneous. 
(3) 60 grams of the mixture was placed into a die box having a rectangular 
face dimension of 5 cm by 7 cm. 
(4) Using a Stokes Press, a weight of 6 tons was applied to form a tablet. 
______________________________________ 
Polyox C.sup.1 8.0% 
Na.sub.2 SO.sub.4 
30.0 
Thiourea 1.0 
Fluorad FC-170.sup.2 
0.25 
Petro BAF.sup.3 43.15 
Perfume 9.0 
Acid Green.sup.3 5.7 
NaBr 2.9 
100.0 
______________________________________ 
.sup.1 PEO resin, M.W. 5,000,000 (Union Carbide Co.) 
.sup.2 Fluorinated alkyl polyoxyethylene ethanol (3M 
.sup.3 99+% active sodium lower alkyl (C.sub.2 -C.sub.4) naphthalene 
sulfonate (Petrochemicals Co., Inc.) 
After stamping, this composition had dimensions of 5 cm.times.7 
cm.times.1.2 cm. 
The tablet is placed in an automatic dispensing device of the general type 
described in the concurrently filed application of Choy, U.S. Ser. No. 
153,997 filed May 28, 1980, and the device is suspended in the flush tank 
of a toilet, using a hanger device of the type described in U.S. Pat. No. 
4,247,070 of Dirksing issued Jan. 27, 1981 and incorporated by reference 
herein. The device operates satisfactorily, i.e. it repeatedly delivers 
metered amounts of a solution of the composition of this example to the 
flush water without interference with the functioning of the dispenser due 
to gel formation.