US 3671439 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
United States Patent Corey et al.
 3,671,439 51 *June 20, 1972 OXYGEN BLEACH-ACTIVATOR SYSTEMS STABILIZED WITH PUFFED BORAX lnventors: Garland G. Corey, Milltown; Bernard Weinstein, Plainfield, both of NJ.
American Home Products Corporation, New York, NY.
Notice: The portion of the term of this patent subsequent to May 9, 1989, has been disclaimed.
Filed: July 22, 1969 Appl. No.: 843,829
 References Cited UNITED STATES PATENTS 2,730,428 l/ 1958 Lindner ..252/95 3,130,165 4/1964 Brocklehurst ..252/186 3,192,254 6/1965 Hayes ..252/186 3,194,768 7/1965 Lindner et al. 252/186 3,454,357 7/1969 Rhees et al. ..23/59 3,449,254 6/1969 Suiter 25 2/99 3,538,005 1 1/1970 Weinstein et al. ..252/99 Primary Examiner-Leon D. Rosdol Assistant Examiner-Irwin Gluck Attorney-Andrew Kafko  ABSTRACT Oxygen releasing bleaches such as perborates are combined with activators and puffed borax to provide compositions unusually stable upon storage under adverse conditions of high temperature and humidity to which they are normally subjected.
9 Claims, No Drawings OXYGEN BLEACH-ACTIVATOR SYSTEMS STABILIZED WITH PUFFED BORAX The invention relates generally to bleach compositions comprising an oxygen-releasing bleach, an activator for the oxygen-releasing bleach and a stabilizer to prevent premature release of the oxygen and breakdown of the bleach composition. More specifically this invention concerns compositions of perborate bleaches, an activator for the perborate bleaches, puffed borax as a stabilizer and an optional non-ionic surfactant. The bleach-stabilizer-activator system may additionally contain additive ingredients common to bleach systems, such as those included in a heavy duty laundry detergent composition.
BACKGROUND OF THE lNVENTlON The use of bleaching agents as aids to laundering is well known. Of the two major types of bleaches, oxygen-releasing and chlorine-releasing, the oxygen bleaches are more advantageous to use in that oxygen bleaches do not attack the fluorescent dyes commonly used as fabric brighteners or the fabrics and do not, to any appreciable extent, yellow the resin fabric finishes as chlorine bleaches are apt to do. However, one major drawback to an oxygen bleach is the high temperatures (l40-l60 F.) necessary to efficiently activate the bleach. The United States washing temperatures are in the range of l20l30 F., below the effective temperatures for activating an oxygen bleach. Considerable effort has been expended to find substances to activate the oxygen bleach at lower temperature.
The use of various substances as oxygen bleaches are taught. These include hydrogen peroxide and per compounds which give rise to hydrogen peroxide in aqueous solution. Suitable compounds include water soluble oxygen releasing compounds such as the alkali metal persulfates, percarbonates, perborates, perpyrophosphates and persilicates. Although not all of the preceding are true persalts in the chemical sense they are believed to provide hydrogen peroxide in aqueous solution. Among the suggested oxygen bleach activators are heavy metal salts of transition metals as cobalt, iron or copper combined with chelating agents as picolinic acid (U.S. Pat. No. 3,156,654) or stronger chelating agents at higher temperatures as methylaminodiacetic acid, aminotriacetic acid and hydroxyethylaminodiacetic acid (U.S. Pat. No. 3,21 1,658). Esters have been suggested as activators for oxygen releasing bleach. Exemplary are chloroacetyl phenol and chloroacetyl salicylic acid (U.S. Pat. No. 3 ,1 30,1 65), triacetyl cyanurate, N,N,N, N'- tetraacetylethylene diamine and sodium-p-acetoxy benzene sulfonate. Recently, benzoylimidazole and its derivatives with some success have been used. The problems inherent in activating oxygen bleach systems is discussed fully in, Effective Bleaching With Sodium Perborate, Dr. A.H. Gilbert, Detergent Age, June 1967 pages 18-20, July 1967 pages 30, 32, 33 and August 1967 pages 26, 27, and 67.
One major drawback which has prevented the widespread use and acceptance of the previously described oxygen bleach-activator systems is that the activators tend to react with the oxygen bleach in the package. This results in limited effectiveness of the bleach composition, a poor commercial product and lack of consumer acceptance. A prime requirement of a commercial bleach product is that it give standardized results, i.e., similar results from similar amounts of bleach at different times. The known activated perborate (oxyg'en) bleach compositions have failed to give such satisfactory standardized results. The premature activation in the package of the perborate bleach by the activator especially under the adversely high humidity conditions present in laundry areas results in products that continuously lose their original bleaching potential during product storage and use. This results in products which do not provide uniform results to the consumer.
uni-v OBJECT OF THE lNVENTlON In the light of the noted disadvantages in using oxygen (perborate) bleaches, it is an object of this invention to provide an oxygen bleach-activator system which has been stabilized against deterioration in the presence of moisture.
ln general, according to this invention, the stabilization of the oxygen bleach-activator system is accomplished by using a specific filler, namely, puffed borax, in the bleach compositions. The pufied borax used in this invention is a known form of borax made by the rapid heating of hydrates of sodium tetraborate. The compound is characterized by versatility of bulk density, large surface area, rapid solubility rate, and high absorptive potential for many substances. The puffed borax contemplated for inclusion in compositions of the invention, is further characterized by having less than '5 moles of water per mole of sodium tetraborate, a bulk density ranging from about 3 lbs/cu. ft. to about 40 lbs/cu. ft. and a particle size distribution based on the desired bulk density and the proper selection of the starting borax feed material. Found to be particularly useful are pufied boraxes having particle size distribution so that the major proportion of the pufl'ed borax is of a size within the U.S. sieve range of from 20 to about +200. In the more preferred fonns over percent of the particles of pufi'ed borax are in the U.S. sieve range from about 40 to 60. At the optimum compositions of the instant disclosed inventions, the bulk density of the puffed borax is about 15 lbs/cu. ft
We have discovered that puffed borax has a surprising and unexpected stabilizing effect on oxygen bleach-activator systems, even when the systems are exposed to extremes of temperature and humidity.
The oxygen bleach-activator compositions of the present invention may also include conventional additives for such compositions. These may include binders, other fillers, builders, optical brighteners, perfumes, colorings, enzymes, bacteriostats, etc., all of which may be added to provide properties required in any particular instance. Additionally, the stabilized oxygen bleach-activator compositions can be incorporated into cleaning compositions containing soap and/or synthetic organic detergents and formulated for use as heavy duty household detergents, fine fabric washing detergent systems or clothes washing formulations in general.
Illustrative of the soaps which may be used in the presentinvention are the well known salts of fatty acids. These may include the Na, K, Li or ammonium salts of nyristic, palmitic, stearic, behenic, oleic, lauric, abietic, capric, caproic, ricinoleic, linoleic, hydrogenated and dehydrogenated abietic acids, the surface active hydrolysis products of tallow, coconut oil, cottonseed oil, soybean oil, peanut oil, sesame oil, linseed oil, olive oil, corn oil, castor oil, and the like.
Illustrative of the synthetic organic detergents useful in the present invention, there may be mentioned long chain alkyl aryl sulfonates such as sodium octyl-, nonyl-, dodecyl-, decyl-, tri-decyl and tetradecylbenzene sulfonates, N-long chain acyl N-alkyl taurates such as sodium oleoyl methyltaurate, sodium palmitoyl methyl taurate, sodium or potassium lauroyl methyl taurate and the corresponding acyl ethyl taurates, long chain alkyl oxyethlene sulfates such as sodium or potassium laurylpolyoxyethylene sulfate, sodium laurylmonooxyethylene sulfate, sodium octadecylpolyoxyethylene sulfate and sodium cetyl polyoxyethylene sulfate, long chain alkyl aryl oxyethylene sulfates such as ammonium, sodium or potassium nonyl-, octyl-, and tridecylphenol monoand polyoxyethylene sulfates, long chain alkyl sulfates such as sodium lauryland stearylsulfates, long chain alkyl isethionates such as sodium oleic isethionate, sodium lauric isethionate, sodium diisopropyl naphthalene sulfonate, sodium isopropyl naphthalene sulfonate, sodium isobutyland diisobutyl naphthalene sulfonate, sodium isohexylbenzene sulfonate, monobutyl biphenyl sodium monosulfonate, monobutylphenylphenol sodium monosulfonate, dibutylphenylphenol sodium disulfonate, lower alkyl sulfates and sulfonates such as sodium sulfate derivative of Z-ethyl hexanol-l sodium 2-ethyl-l-hexenyl sulfonate, sodium isooctyl sulfonate, sodium isononyl (also triisopropylene) sulfonate, lower alkyl esters of aliphatic sulfocarboxylic acids such as sodium diamyl sulfosuccinate, sodium diisobutyl sulfosuccinate, sodium dihexyl sulfosuccinate, sodium dioctyl sulfosuccinate, sodium triamyl sulfotricarballylate, sodium triisobutyl sulfotricarballylate, and sodium tri-nbutyl sulfotricarballylate.
While the foregoing sodium salts of the above detergents may be preferred, other alkali metal and amine salts may be employed, as, for example, those with potassium, ammonium, lower alkyl amines such as methylamine, ethylamine, propylamine and isopropylamine, lower alkylolamines such as mono, di-, and triethanoland isopropanolamines, cyclic amines such as cyclohexylamine, morpholine, and pyrrolidine and the like.
The above-mentioned detergents may be used alone or may be employed as mixtures. Additionally, the detergents can be used in combination with the water-soluble soaps and water conditioners. The term water conditioner as used in the present specification and claims designates those compounds which sequester, or inactive water hardness and aid in cleaning, and the term is fully intended to include both the inorganic and organic complexing agents, sequestering agents and chelating agents.
Referring first to the organic type of chelating and sequestering agents, the ethylene diamine tetraacetic acid type and its salts and nitrilotriacetic acid and its salts are among the most effective. While these foregoing materials are referred, there are numerous other types of organic products suppressors, preservatives and bacteriostats and baclericides (trichlorocarbanilide, trichlorosalicylanilide, tribromosalicylanilide). Each ingredient is selected to perform a specific function. The corrosion inhibitor protects the metals used in washing machines. The anti-redeposition agent is used to aid in preventing removed soil from redepositing on the fabric being washed. The foam stabilizer or suppressor aids in tailoring the sudsing characteristics of the product. The optical brighteners aid in maintaining fabric whiteness or brightness.
The compositions contemplated within this invention may be prepared in any forms recognized in the art. This would include granules, powders, beads, tablets, individual premeasured units (envelopes, packets, etc.) or combinations with coatings of various materials selected to provide a differential release rate of the ingredients forming the compositions.
The following examples are illustrative of the present inventron.
EXAMPLE I Samples were made by mixing the activating system, BID (Benzoylimidazole) with a number of fillers referred to hereinafter, and then combining the above mixture with sodium perborate monohydrate. The samples were than stored at 90 F./90% R.H. in open containers for 72 hours. The samples were removed and titrated for the amount of active oxygen present with the standard permanganate titration. On Table 1, following column I specifies the filler tested. Columns II to IV, respectively, set out the amounts of filler, BID and sodium perborate in the compositions tested. Column V lists the measured 0 loss under the adverse storage conditions.
TABLE I I II III IV Percent active oxyrzen Grams Na loss after perborate 72 hours Grams Grams -H2O (15.4; at 110 F.. Filler offiller BID active 0;) 90? R.H.
Iufivd liorax t J. "U U. 25 0. 23 2'1 Borax rlr-callydrale" 2. U0 0 25 0. 23 4) Low density sodium carbonate (Flo/pin .2. 00 (J. 25 0. 23 I4 Light dcusitysudiumtripolyphosphate 2.00 0.25 0 23 2'1 Soap flakes s 2.00 0.25 0.23
offered and reference may be had to the book Chemistry of the Metal Chelating Compounds," by Martel] and Calvin, for many further examples. Illustrative of the inorganic water conditioners useful in the present invention are the zeolites (hydrated silicates of aluminum and either sodium or calcium or both), sodium carbonate, sodium phosphate, sodium acid phosphate, tetrasodium pyrophosphate, sodium tripolyphosphate, trisodium phosphate, sodium metaphosphate, sodium hexametaphosphate and sodium tetraphosphate. While the sodium salts of the inorganic compounds are preferred, the other alkali metal salts such as the potassium and lithium salts may be used.
Suitable additives, e.g., binders, additional fillers, builders, optical brighteners, perfumes, colorings, bacteriostats, etc., may be added to provide properties regarded as desirable in particular instance, as noted hereinbefore. Illustrative of some of the various additives used by those skilled in the detergent and soap art are builders (borax, sodium sulfate, sodium carbonate, etc.) corrosion inhibitors (sodium silicate), antiredeposition agents (carboxymethyl cellulose), fabric brighteners fluorescent or optical pigments, fillers (talc), bin ders (gums, starches, dextrins), coloring, foam stabilizers and Table 1 clearly delineates the unexpected stability of oxygen bleach-activator systems containing puffed borax and those containing standard fillers including light density fillers or soaps.
EXAMPLE II A sodium perborate bleach composition was formulated into activated bleach compositions containing picolinic acid (Z-pyridinecarboxylic acid) and cobalt sulfate heptahydrate (CoSO,-7I-I O). The sodium perborate bleach composition (control) was compared to the activated bleach compositions, with and without puffed borax, after storage under adverse conditions by measuring the amount of active oxygen lost. The compositions were prepared as follows:
a. 5 g. picolinic acid was dissolved in g. ethanol to give b. 50 g. (I) was combined with 50 g. puffed borax (6 lbs/cu.
ft.) to give (II);
c. 50 g. (II) was combined with ISO g. ofa sodium perborate bleach composition to give III);
d. 100 g. (III) was combined with l g. cobalt sulfate heptahydrate to give (IV);
e. I00 g. sodium perborate bleach composition was combined with 0.6 g. picolinic acid and 1.0 g. cobalt sulfate heptahydrate to give (V).
The samples were stored in closed glass containers at 90F./ 90% RH. for 42 days. During storage the active oxygen content of the samples were measured using a standard perman- 5 ganate titration.
TABLE 2 Active Oxygen loss from Sample Composition 7-42 days at 90F./90% RLH.
Control None Sodium perborate composition Sodium perborate composition and CoS0 -7l-l 0 (Puffed Borax and Picolinic Acid) Sodium perborate composition* and Picolinic Acid and CoSO,-7H,O
Sodium perborate composition is a commercial type perborate bleaching composition containing about 4.3% available oxygen from sodium perborate monohydrate, sodium tripolyphosphate, sodium silicate, sodium sulfate, non-ionicsurfactant and additives such as perfumes, brighteners, etc.
EXAMPLE Ill A perborate activating system was prepared in the following manner: One gram of benzoylimidazole (BID) was solubilized in a non-ionic surfactant or glycol which was liquid at ambient room temperature. Then 0.50 g. of the non-ionic-BID mixture was mixed with 2.00 g. of puffed borax (l5 lbs/cu. ft. density). This puffed borax activator system was admixed with sodium perborate monohydrate (15.2 percent active oxygen) giving a BlDzNa Perborate monohydrate ratio of 0252023. The sample was then stored in open containers at 90 F./75% RH. for 72 hours, after which time active oxygen content was determined by the standard permanganate titration.
The non-ionic surfactants used will preferably (although not necessarily) be liquid at ambient use temperature. The non- 5Q ionic surfactant glycol may be chosen from the following general classes:
1. Straight chain alkylphenoxypoly (ethyleneoxy) ethanols having the general formula:
wherein R is an alkyl radical and n is the number of moles of ethanol oxide in the molecule (lgepals, GAF).
2. Ethoxylates of isomeric linear secondary alcohols having the general formula:
wherein n is the number of moles of methylene and x is the number of moles of ethylene oxide in the molecule. (Tergitols, Union Carbide).
' 3. Condensation products of ethylene oxide with a hydrophobic base formed by the condensation of propylene oxide with propylene glycol having the general formula:
wherein a and c represent moles of ethylene oxide and b represent moles of propylene glycol. (Pluronics, Wyandotte Chemical).
4. Addition products of propylene oxide to ethylene diamine followed by the addition of ethylene oxide having the general formula:
wherein x and y represent respectively the number of moles of propylene oxide and ethylene oxide in the molecule. (Tetronics, Wyandotte Chemicals).
5. Ethylene oxide adducts of straight chain alcohols having the general fonnula:
CPL-(CH )--CH (O--CH,-CH ),,-OH
wherein x is the number of methyl groups (chiefly C to C and y is the number of moles of ethylene oxide present. (Alfonics, Conoco).
6. Glycols such as propylene glycol, triethylene glycol and trimethylene glycol.
For comparison purposes a cationic surfactant mixture was also used. A mixture of n-alkyl-di(lower)alkylbenzyl-ammoniurn chlorides and n-alkyl-di(lower)alkyl(lower)alkylbenzylammonium chlorides was incorporated in sample compositions.
Each sample of table 3 contains 0.25 gm. of ED and 0.23 gm. of Na Perborate'l-l o.
TABLE 3 A B C D E Gm. Gm. Gm. Active Sample Sur- Sur- Pufl'ed Borax Oxygen loss factant factant 1 None None 44 2 None 2.00 23 3 Pluronic" 0.25 2.00 20 4 Alfonic 0.25 2.00 15 lO-l 2-6 5 Triethylene 0.25 2.00 10 Glycol 6 Tetl'onir: 0.25 2.00 l l 7 Tergitol" 0.25 2.00 22 8 BTC' 0.25 2.00 32 (a) Pluronic L-6l-having a molecular weight of the poloxypropylene hydrophobic base of about 1750 and about 10% polyoxyethylene in the total molecule and an average molecular weight of about 2000.
(b) Alfonic l0-l2-6-having an average ethylene oxide content of about 60% and an alkyl chain of C to C (c) Tetronic 70 I having a molecular weight of about 3600.
(d) Tergitol l5-S-9having C -C linear alcohol and 9 moles of ethylene oxide per molecule.
(e) BTC 2l25(50% active) (US. Pat. No. 2,676,986) 25% n-alkyl (60% Cu. 30% Cm- 5% C 5% Cw) dimethyl benzyl ammonium chlorides, 25% n-alkyl (50% C 30% C 17% C 3% C dimethyl ethylbenzyl ammonium chlorides. 50% inert ingredients.
It is apparent from the above data that: l the use of puffed borax as a filler increases the active oxygen life of Na Perborate, (2) the use of non-ionic surfactants tends to increase the active oxygen life of Na Perborate while cationics have an opposite effect (Sample No. 8) and (3), the various non-ionics give varying results.
EXAMPLE IV The effect of puffed borax on various sodium perborate compositions was tested. The results expressed as percent tea stain removal was measured by a Tergotometer after washing at 120 F. for 20 minutes. The data in Tables 4 and 5 clearly BlD 215 demonstrates that the effect of oxygen bleach activator is unsodium perborate Compositionm 50-00% hindered by the presence of puffed borax. The compositions are expressed as percent by weight. ""Composition as defined in Example ll containing 30% sodium per- 5 borate monohydrate.
TABLE 4 ll. Dry Blended Oxygen Releasing Bleach Active Oxygen 0.75% wlth heavy duty detergent composmo" Puired Borax (6 to 30 lbs./cu. n. 50.0% BID 6.0% Sample A B C D 10 Pluronic L-61 6.0% Na Perborate H O -16% active oxygen) 5.0% Sodium Tripolyphosphate 32.0% 70 BID 5.85 3.30 1.69 0.00 Na Perborate 5.15 2.80 1.45 2.92 2;' bngmne" l 00 0% (15-16% Active 02) ..q. Puffed Borax 44.50 46.95 48.43 48.54 I Detergent 44.50 46.95 48.43 48.54 15 What IS claimed is: Composition 1. A stabilized oxygen-active bleaching composition con- Zn Tea 21mm 30 75 65 47 sisting essentially of about 1 to about 30 percent by weight of an inorganic peroxy compound which is an oxygen releasing bleaching substance, about 1.5 to about percent by weight TABLE 5 20 of an activator for said oxygen releasing bleaching substance, selected from the class consisting of benzoylimidazole, a Without heavy duty detergent composition chelating agent-transition metal salt composition, chloroacetyl phenol, chloroacetyl salicycltc acid, tnacetyl Sample A B C D cyanurate, N, N, N, N -tetraacetylethylene diamine and sodium-p-acetoxy benzene sulfonate, about 40 to about 95.5 per- BID 17.44 10.44 6.19 0.00 cent by weight of a puffed borax which is characterized by 2%} glal garlrra '0 1 9423 53! 10-31 having a bulk density in the range from about 3 lbs/cu. ft. to
CIIVE puffed Borax 67.12 8033 8850 8969 about 40 lbs/cu. ft., a particle size in the U. S. sieve range of Tea stain 6500 40.00 1600 0 60 from about -20 to about +200 and having less than about 5 Removal moles of water per mole of sodium tetroborate, and about 5 to about 25 percent by weight of an additive selected from the "A commercially available heavy duty detergent composition comprisclass consstmg of a non-mm: Surfactant and a glycol Sald ing about 20% alkyaryl sulfonate, 45-50% sodium tripolyphosphate s y being Selected from the class consisting of P py and q.s. to 100% of additives. glycol, trimethylene glycol and triethylene glycol.
2. The composition of claim 1 wherein said peroxy com- The formulations of the present invention may be produced ound i odi m erborate, by various conventional mixing operations. These would in- 3. The composition of claim 1 wherein said activator for the clude dry blending, spray drying and wet (slurry) blending oxygen-active bleach substance is benzoylimidazole. methods. It has been found that the best stability charac- 4. The composition of claim 1 wherein said activator for the teristics of perborate bleaches are produced when the activa- 0 oxygen-active bleach substance is composed of a chelating tor is mixed with a non-ionic (preferably liquid at ambient agent andatransition metal salt. room temperature) and this mixture incorporated with puffed 5. The composition of claim 4 wherein said chelating agent borax. If desired, small amounts (up to 5 percent by weight) of is picolinic acid and said transition metal salt is cobalt sulfate. an alcohol such as methanol, ethanol or isopropanol may be 6. The composition of claim 1 wherein said puffed borax has included to act as a thinning agent in preparing the composia bulk density of about 15 lbs/cu. ft. and wherein the major tions of the present invention. portion of the particle size in the U.S. sieve range is from In general, the compositions of the present invention may about-+40 to about +60. comprise, by weight: 7. The composition according to claim 1 wherein said addi- Puffed Borax from about 0.1 percent up to about 99.0 pertive is a glycol which is triethylene glycol and is present in an cent. Oxygen bleach activator from about 0.1 percent up 5 amount between about 5 and about 10 percent by weight of to about 25.0 percent. said composition. Non-ionic surfactant up to about 25.0 percent. 8. The composition according to claim 1 wherein said ox- Oxygen releasing bleach substance from about 0.1 percent ygen-releasing bleaching substance is a perborate.
up to about 40.0 er ent, 9. A stabilized oxygen-active bleaching composition con- Builders and fillers up to about 99.0 percent. 55 sisting essentially of about 50.00 percent by weight of a puffed Bleach composition adjuvants (brighteners, perfumes, deborax, about Percent y weight of a benzoylimidazole. tergents, etc.) up to about 99 percent. about 5.0 percent by weight of sodium perborate, about 32.0 In the more preferred form, the compositions of the active percent by weight of sodium tripolyphosphate, about 6.0 peringredients of the present invention may comprise, by weight: Cent by weight of a compound of the formula Puffed Borax from about 40.0 percent up to about 95.50
percent. Oxygen bleach activator from about 1.50 per- HO(CHZCHO)F((EHCHOMTwHZCHEO)PH cent up to about 20.0 percent. CH: Oxygen releasing bleach substance from about 1.00 percent up to about 30.0 percent. having a molecular weight of about 2,000 and a and c are Particular compositions which utilize the principles taught Selemed Such that the fiompound has about P of b th present invention are, b i h polyoxyethylcne by weight, said puffed borax being characterized by a bulk density of about 15 lbs/cu. ft. and a particle 1v Spray Dried Build Oxygen Releasing Bleach size in the U.S. seive range from about -20 up to about +200 Active Oxygen 2.25% with the major portion 111 the U.S. sieve range of from about Pufied Borax 47.75% +40 to about 0