US3927967A - Photoactivated bleaching process and composition - Google Patents

Abstract

A process of bleaching textiles, especially in relation with a washing and bleaching process for household laundry, is provided by the use of photoactivating compounds such as sulfonated phthalocyanine in the presence of visible light and oxygen.

Description

United States Patent 1191 Speakman PHOTOACTIVATED BLEACHING PROCESS AND cowosmou [75} Inventor: Peter Roscoe Hartley Speakman,

Newcastle-Upon-Tyne, England [73] Assignee: The Procter & Gamble Company, Cincinnati, Ohio [22] Filed: July 6, 1973 [2|] Appl. No.: 377,169

name us. Application Data [63] Continuation-impart of Ser. No. 259,326, June 2,

1972, abandoned. i

[30] Foreign Application Priority Data July 10, l972 United Kingdom 32222/72 [52] US. Cl. 8/103; SH 1 1; 8/107; .8/108; 8/110; 252/95 [51] Int. CL... D06L 3/02; D06L 3/04; D06L 3/00;

[ 1 Dec. 23, 1975 2,662,897 l2/l953 Pedersen 8/l XA 2,761,868 9/l956 Lacey 8/1 XA 2,925,423 2/1960 Wcinrnayr 8/l XA 3,496,l$0 2/1970 Kropp 8/] l I 3,619,109 ll/l97l Vollman..... 8/l XA 3,635,806 [/1972 Hecltcrt 3/1 H 3,7l6,325 2/1973 Aspland 8/1 XA OTHER PUBLICATIONS Journal of the American Chemical Society Vol. 42, pp. 720-724.

Journal of the American Chemical Society Vol. 86, pp. 3879-3882.

Primary Examiner-Benjamin R. Padgett Assistant Examiner-Donald P. Walsh Attorney, Agent; or Firm-T. H. O'Flaherty; W. H. Gould; F. L. Collins [57] ABSTRACT A process of bleaching textiles, especially in relation with a washing and bleaching process for household laundry, is provided by the use of photoactivating compounds such as sulfonated phthalocyanine in the presence of visible light and oxygen.

18 Claims, No Drawings PHOTOACTIVATED BLEACHING PROCESS AND COMPOSITION CROSS-REFERENCE This application is a continuation-in-part of copending application Ser. No. 259,326 filed June 2, 1972, now abandoned.

It relates to a process for bleaching textiles and particularly, although not exclusively, to a combined washing and bleaching process for household laundry.

In conventional household laundry processes for white goods such as bed linen, table line, and white cotton goods, the articles are subjected to a combined washing and bleaching process in which the articles are treated in an aqueous bath containing an organic detergent and a bleaching (i.e., stain removing) agent. Other conventional detergent aids such as alkaline builders, for example sodium tripolyphosphate; soil suspending agents, for example sodium carboxymethyl cellulose; and optical brightening agents may also be present.

A well established method of removing stains from textiles, especially in domestic laundry operations, is to treat the textiles with hydrogen peroxide addition compounds such as sodium perborate and sodium percarbonate, especially in the presence of a detergent composition. Such hydrogen peroxide addition compounds, or peroxyhydrates, in aqueous solution, produce hydrogen peroxide which in turn decomposes to release oxygen which oxidises the stains to colorless or water-soluble substances. However, this process is wasteful as much of the oxygen released from the hydrogen peroxide escapes as molecular oxygen, and is not used in the oxidation of stains.

Many attempts have been made to improve the efficiency of this process by controlling the rate of release of oxygen from the peroxyhydrate. German Specification No. 27 l ,l 55 assigned to Chemische Werke von H. Byk, published Mar. 10, l9ll, teaches the use of tin derivatives for this purpose; U.S. Pat. Nos. 2,121,952 and 2,141,189, assigned to Henkel and Co., issued June 28, 1938 and Dec. 27, I938 respectively, propose the use of alkaline earth silicates; British Patent Specification No. 765,750, assigned to Thomas Hedley and Co., published Jan. 9, 1957, proposes the use of ethylene diamine tetraacetic acid or beta-hydroxyethyl ethylene diamine triacetic acid; and German Patent Specification No. 72l,317, assigned to l. G. Farbenindustrie, published Apr. 30, I942, discloses the use of amino carboxylic acid substituted in the alpha position by more than one carboxyl radical.

In some instances, the stain removal may be carried out as a separate step using a compound which liberates available chlorine, such as sodium hypochlorite or N-ehloro organic compounds such as dichlorocyanuric acid or its salts or trichlorocyanuric acid.

These conventional chemical processes for stain removal result in varying amounts of degradation of the textile fibers.

Dye-photoaetivated oxidation reactions are known in organic chemistry, but there has been no attempt to apply this type of oxidation in textile bleaching processes. [t has now been discovered that very effective stain removal from textiles can be obtained by subjecting the textiles to treatment in an aqueous bath in the presence of atmospheric oxygen and certain photoactivating compounds, while at the same time irradiating the textiles with visible light, and this stain removal process can be conveniently combined with a conventional washing process.

It has also been discovered that the efficiency of peroxyhydrate bleaching agents can be greatly enhanced by including in the peroxyhydrate-containing composition an alkaline detergency builder and a photoactivator, and irradiating the textiles with visible light.

According to this invention, a process for removing stains from textiles comprises treating the stained textiles in aqueous bath containing at least one alkaline detergency builder salt and an effective amount of a photoactivator selected from the group consisting of eosin, rose bengal, fluorescein, chlorophyll, metal-free porphyrin, sulfonated phthalocyanine and sulfonated zinc phthalocyanine in the presence of oxygen, the textiles being irradiated with visible light during the process.

The process is preferably carried out as a combined washing and stain-removing process, in which case the aqueous bath also contains an organic detergent such as soap or synthetic detergent and may also contain other detergent adjuvants such as soil suspending agents, for example, sodium carboxymethyl cellulose; optical brightening agents; suds control agents; and perfume. Effective photoactivators are eosin, rose bengal, fluorescein, chlorophyll, metal-free porphyrin, sulfonated phthalocyanine and sulfonated zinc phthalocyanine. Preferably the proportion of photoactivator is 1-50 mg. per liter of the treatment bath. The preferred photoactivator is sulfonated zinc phthalocyanine, especially when free of unsulfonated zinc phthalocyanine.

A preferred embodiment of the process of this invention includes a peroxyhydrate in the aqueous bath. By peroxyhydrate is meant hydrogen peroxide or any compound which in aqueous solution yields hydrogen peroxide. A variety of such compounds exists. Many of them are prepared by crystallization of salts from solutions containing hydrogen peroxide solution. The most important are: sodium perborate monohydrate and tetrahydrate, sodium persulfate, and sodium percarbonate; others are various phosphate peroxyhydrates for example Na P O .2H O A suitable organic peroxyhydrate is urea peroxide CO(NH .H O.

Suitable alkaline detergency builders for use in the invention are those water soluble alkaline salts which are used in conventional heavy duty detergents. Examples of such salts are: sodium carbonate, sodium silicate, sodium orthophosphates and polyphosphates such as pentasodium tripolyphosphate.

The liquor used to treat the stained textiles preferably contains from 1 to 50 mg. per liter of the photoactivator, sufficient peroxyhydrate to provide from 0.02 to 0.2 gm./liter of available oxygen, from 0.2 to 2.0 gm./liter of alkaline builder salt and 0 to 2.0 gm./liter, and from 0.02 to 0.2 gm./liter of organic detergent.

During the bleaching process, the textiles must be irradiated with visible light including light of wavelength 640 nm. and higher. Suitable sources of light are sunlight, normal daylight or light from an incandescent electric lamp bulb.

The intensity of illumination required depends on the duration of treatment and may vary from the normal domestic lighting (l50250 ft. candles, daylight or artificial light Le. normal conditions of indoor illumination) in the case of several hours soaking, to the inten sity obrained from an electric light (for example l00 watt incandescent bulb) mounted within a short distance (for example 6 inches) of the surface of the treatment bath when the stain removal process is carried out simultaneously with a washing process.

The stain removing process of the invention is suitably carried out in the temperature range from 50F. to 180F., preferably from 80F. to 160F. Suitable times are 15 minutes and longer, for example a period of from 15 minutes to 5 hours, preferably 15 minutes to 60 minutes.

The present invention also provides a detergent composition suitable for use in the process comprising the conventional detergent ingredients, including an organic detergent, at least one builder salt, and a photoactivator selected from the group previously named. The organic detergent present may be soap or synthetic detergent.

This invention further provides a bleaching composition comprising a peroxyhydrate, an organic detergent, an alkaline detergency builder, and a photoactivator as defined above.

The photoactivator is preferably present in an amount from 0.025 to 1.25 percent by weight of the total composition. The preferred photoactivator is sulfonated zinc phthalocyanine, especially when free of unsulfonated zinc phthalocyanine.

While not wishing to be bound by theory, it is believed that the stain removal process follows the following course; first the photoactivator absorbs light to raise it to the triplet state sens hv -sens This reacts with triplet oxygen to form singlet O2 +"sens sens The singlet oxygen oxidizes the stain to colorless or water soluble oxidation products 02 stain stain 0,

Such a theory is suggested for the photoactivated oxidation of organic compounds by Foote and Wexler, J.A.C.S. 86 3880 (1964).

Preparation of Sulfonated Zinc Phthalocyanine. Zinc phthalocyanine (2 g.) and oleum (2 ml., 30% free sulphur trioxide) were heated at 100C. for 3 hours. The cooled mixture was neutralized (pH 7) with N sodium hydroxide (added dropwise with stirring). The solid residue was filtered and dried under vacuum. Yield of sulfonated zinc phthalocyanine (contaminated with sodium sulfate) was L8 g.

The unpurified product was used in Examples l-Vll hereinafter described.

A very effective photoactivator for use in the process of this invention is sulfonated zinc phthalocyanine which is free from unsulfonated zinc phthalocyanine. The product can be made by a method similar to that described above, but using a greater excess of oleum in the sulfonation stage. A typical preparation is as follows: 10 grams of zinc phthalocyanine and ml. of oleum (30% free 50 were stirred briskly together at 1()0-l2()C. for 3 hours. (Efficient stirring is essential to insure that the finished product contains no unsulfonated material.) The mixture was cooled at 0C. and neutralized to pH 7-8 by adding percent caustic tion and the solid was washed with 120 ml. of cold water. The solid (19 g.) was a mixture of the sodium salt of sulfonated zinc phthalocyanine and sodium sulfate. It is a very effective photoactivator for the bleaching process, especially when used in an amount of6 mg. per liter.

The filtrate from the preparation when evaporated to dryness yielded a solid residue (32 g.) which is also a mixture of the sodium salt of zinc phthalocyanine and sodium sulfate but containing a higher proportion of sodium sulfate. This is an effective photoactivator for the bleaching process especially when used in an amount of 50 mg. per liter.

Thin layer chromatography on silica gel using the lower phase of a mixture of two parts by volume of pyridine, one part by volume of chloroform and one part by volume of water as the eluant, and running unsulfonated zinc phthalocyanine on the same chromatogram, as standard, shows that both samples of the sulfonated material are free from unsulfonated zinc phthalocyanine. The absence of unsulfonated zinc phthalocyanine can also be demonstrated by electrophoresis on a polyacrylamide gel using a solution buffered at pH 8.

The active material is believed to be a mixture of di-, triand tetrasulfonates of zinc phthalocyanine, with only traces of the monosulfonate. Small variations in the proportions of these components do not appear to affect the efficacy of the product as a photoactivator.

It has been found that if the photoactivator is contaminated with unsulfonated phthalocyanine, cloth which is contacted with such material in the absence of light may be stained with greenish spots.

Sulfonated zinc phthalocyanine which is contaminated with unsulfonated material can be purified by washing the material, on a sintered glass filter with copious amounts of water until no more will dissolve. The unsulfonated material is left undissolved on the filter, and the filtrate is evaporated to dryness to produce a photoactivator which is free from unsulfonated material.

It is essential that the bleach liquor contains a water soluble alkaline detergency builder salt as is shown by the following tests.

In the following tests two standard tea-stained cotton swatches (2% inches X 2% inches) were stirred with a magnetic stirrer in a l liter of water in a beaker of 4% inches diameter having a 100 watt tungsten filament electric lamp bulb mounted 3 inches above the surface of the liquid. The temperature and times are as stated below and the water contained additives as stated below. The photoactivator used was sulfonated zinc phthalocyanine free from unsulfonated phthalocyanine and prepared by the method described above. Other addivites were as shown. At the conclusion of the test the swatches were rinsed and dried and percentage stain removal was assessed by measuring the reflectance of light from the unstained cloth, the stained cloth and the treated cloth. The results are shown in soda solution. The resulting paste was filtered by suc- Table Table l Content of photo 1 liter of bleach bath Time it Stain emp activator Surface Active Agent Builder (g.) pH ("C) (mins) reduction 25 mg. 0 l) 6 50 30 0 25 mg. 900 mg. Na linear alkyl (C 0 6 S0 30 O Table l-contmued Content of photo- 1 liter of bleach bath Time /r Stain em activator Surface Active Agent Builder (g.) pH (C l (mins) reduction benzene sulfonate 25 mg. 900 mg. Na linear alkyl (C 0 S0 30 (1 benzene sulfonate mg. 700 mg. Na decyl sulfonate 0 6 50 0 25 mg. 700 mg. Na decyl sulfonate 0 10 50 30 0 25 mg. 500 mg. dodecyl betaine 0 6 50 30 0 25 mg. 200 mg. dimethyl octadecyl amine oxide 0 6 50 30 0 25 mg. 0 1.6 STP 50 3O 45 25 mg. 900 mg. Na linear alkyl (C 1.6 STP 50 30 46 benzene sulfonate 25 mg. 0 1.29 Na citrate 50 30 33 25 mg. 500 mg. tridecanoimide 1.6 STP 50 30 33 25 mg. 700 mg. Na decyl sulfonate 1.6 STP 50 30 40 25 mg. 700 mg. K dodecyl sulfate 16 STP 50 30 47 25 mg. 500 mg. C E 1.6 STP 50 30 33 25 mg. 500 mg. dodecyl betaine 1.6 STP 50 30 40 25 mg. 200 mg. dimethyl octadecyl amine oxide 1.6 STP 50 30 30 25 mg. 500 mg. dodecyl betaine 1.2 Na citrate S0 30 l 1 25 mg. 500 mg. tridecanoimide 1.2 Na citrate 50 30 1 1 25 mg. 500 mg. C E 1.2 Na citrate 50 30 33 25 mg. 500 mg. dimethyl dodecyl amine oxide 1.2 Na citrate 50 30 33 5 mg. 0 1 M co 50 25 32 5 mg. 0 1.2 m sic. 50 25 27 5 mg. 0 0 50 25 0 STP signifies pentasodium tripolyphosphate Table 1 shows that a builder salt is necessary. Mere alkalinity is not effective, nor is a surface active agent. in the absence of builder. effective.

Suitable buildersare lllpb citrate.

Sodiumdodecyl (linear) benzene 17.6%

sulfonate gogium toluelne sulfonate 1.8

o ium tri hos hate 46.2

Sodium sili tt e p 7.3 Coconut fatty acid monoethanolamide 1.9

Sodium carhoxymethyl cellulose 1.0

Ethylene diamine tetraacetic acid 0.3

sodium salt Perfume 0.1

Moisture 10.0 Sodium sulfate balance The photoactivator was a sulfonated zinc phthalocyanine and was present at a level of 5 mg. per liter. The test was carried out in a beaker whose wall and base was covered on the outside with aluminum foil and whose top could be completely covered by an llford Glass Light Filter. The source of light was a 100 watt Incandescent lamp mounted 6 inches above the surface of the liquid. The test swatches were stirred for 30 minutes at 50C.

The light filters used were Tricolour Red" which transmits over the wavelength range 640 nm up to infra-red, and Cyan" which transmits in the range 360-580 nm with no transmission in the 590-690 nm range and very little above 690 nm.

The results obtained were as follows:

carbonate and sodium silicate.

Stain reduction Under the same conditions but in the absence of the photoactivator, treatment under unfiltered light gave a stain reduction of 30 percent.

It is clear, therefore, that wavelength in the range 640 nm to the upper limit of the incandescent lamp (about 720 nm) are required. The photoactivator itself absorbs strongly in the range of 640-690 am so that it appears highly probable that this is the effective wavelength band.

A suitable source of light is one or more incandescent filament lamps. Certain fluorescent electric lamps although apparently emitting white light are not suitable, apparently because they do not emit strongly in the 640-690 nm band.

Suitable intensities of light are provided by a watt lamp emitting 1000-1200 lumens mounted 3 to 6 inches above the surface of the liquid. The time required for stain removal can be shortened by using more powerful lamps. such as a 500 watt Photoflood" light which emits 16.000 lumens.

EXAMPLEI Four grams of the synthetic detergent powder A referred to above was added to 1 liter of water at 50C in a beaker of 4% inches diameter and the solution was stirred for 30 seconds using a magnetic stirrer. The required amount of sulfonated zinc phthalocyanine was added and the solution was stirred for a further minute. Two standard tea-stained cotton cloth swatches (each 2% inches X 2% inches) were added to the liquid and a 500 watt Photoflood lamp was mounted 3 inches above the surface of the liquid. The liquid was stirred for 30 minutes at 50C with the light on, after which the swatches were removed, rinsed, dried between filter papers and ironed. Stain removal was estimated by 7 measuring the reflectance of the fabric before and after treatment.

The results are tabulated below:

Concentration olsulfonated zinc phthalocyanine lug/liter 7r Stain removal Photoactivators Stain Removal Rose bengal 39 Eosin 53 A similar experiment carried out for 30 minutes in the absence of the photoactivators and in the absence of the light, but with l g. per liter of sodium perborate in the wash liquor resulted in 38% stain removal.

Effective removal of stains can be obtained if the above process is carried out at ordinary temperatures outdoors, the textiles in the treatment bath being exposed to daylight, preferably sunlight.

The process is therefore admirably suitable for household laundry purposes in those countries where domestic laundry operations are carried out outside, usually in strong sunlight using water at the ambient temperature. Under such outdoor conditions, agitation of the bath is not convenient and longer exposure times may be required than are necessary when the process is carried out in an agitated bath under artificial light.

The present invention also includes a detergent composition comprising an organic detergent compound and a photoactivator selected from the group consisting of eosin, rose bengal, fluorescein, chlorophyll, metal-free porphyrin and sulfonated zinc phthalocyanine, especially when free from unsulfonated zinc phthalocyanine. Preferably, the photoactivator is present in an amount of 0.025 to I25 percent by weight of the total composition.

EXAMPLE ll This Example is illustrative of the process when carried out under normal outdoor conditions. The detergent composition was the same as that used in Example Two standard tea-stained cotton cloth swatches (each 2% inches X 2% inches) were added to 1 liter of water C (59F) containing 4 g. of the detergent composition and 30 mg. of sulfonated zinc phthalocyanine in a plastic wash bowl.

The bowl was placed in the open air, the sky being overcast but intermittent sunshine. The contents of the bowl were not agitated.

After 2 hours, the percentage stain removal was 50 percent, and after 5 hours, there was 70 percent stain removal.

Similar experiments carried out using the photoactivator but in the absence of detergent composition resulted in 16 percent stain removal in two hours. and an experiment using water alone resulted in zero removal of stain in 2 hours. The intensity of illumination during the experiment varied from 20000 to 40,000 lumens.

The embodiment of the invention including peroxyhydrate in the aqueous bath is illustrated by the following Examples. In each such Example, two stained cotton swatches were treated in l liter of solution agitated by a magnetic stirrer. The solution, which was made up from 18 hard water, contained 0.4 percent by weight of a commercial granular detergent composition having the following composition:

Sodium dodecyl (linear) benzene sulphonate Sodium toluene sulphonate Sodium tripolyphosphate Sodium silicate Coconut fatty acid monoethanolamide Sodium carboxymethyl cellulose Ethylene diamine tetra acetic acid sodium salt Perfume Moisture Sodium sulphate Balance EXAMPLE Ill Test Conditions 30 min. wash at 130F. in l liter ofsolution. watt incandescent lamp 6 inches above the bath.

Test Fabric Tea-stained cotton.

Treatment Bath Stain Removal (a) 0.4% detergent composition H] (b) as (a) 0.0006% photoactivator 49 (c) as (a) 0.l% sodium perborate 30 tetrahydrate (d) as (b) 0.1% sodium perhorate 79 tetrahydrate EXAMPLE IV Test Conditions As in Example Ill.

Test Material Coffee-stained cotton.

Treatment Bath Stain Removal (a) 0.4% detergent composition 0.1% 73 sodium perhorate tetrahydrate (b) as (a) 0.0006% photoactivator 89 EXAMPLE V Test Conditions 3 hour soak under indoor daylight conditions (250 ft. 5 candles) starting temperature 130F.

Test Mate rial Tea-stained cotton (as in Example III).

Treatment Bath it Stain Removal (a) 0.4% detergent composition 48 sodium perborate tetrahydrate (b) as (a) 0.0006% photoactivator 67 EXAMPLE VI Test Conditions 3 hour soak under indoor artificial light 150 ft. candles), starting temperature 130F.

Test Material Tea-stained cotton (as in Example Ill).

Treatment Bath Stain Removal (a) 0.4% detergent composition 0.1% 48 sodium perborate tetrahyclrate (b) As (a) 0.0006% photoactivator 63 EX AMPLE VII Test Conditions 30 minute wash at 122F. in 1 liter of solution. 100 watt incandescent lamp 6 inches above the bath.

Test Material Tea-stained cotton.

Treatment Bath Stain Removal (a) 0.4% detergent composition 24 (b) as (a) 0.075% sodium percarbonate 36 (c) as (b) 0.0002% photoactivator 72 EXAMPLE VII] The photoactivator was a mixture of sulphonated llItC phthalocyanine and sodium sulphate prepared from the mother liquor obtained during the preparation of sulphonated Linc phthalocyanine for Examples l-Vll. It has an activity of approxi mately 55 that of the photoactivator of Examples l-Vll.

Foregoing Examples lll-Vlll show that the presence of the photoactivator enables a considerably better bleaching effect to be obtained than is obtained by the peroxyhydrate alone, and that the improved effect is greater than would be expected from a mere addition of the effect of the peroxyhydrate alone and that of the photoactivator alone (i.e. photoactivator and atmospheric oxygen). It is believed that using the photoactivator enables evolved oxygen from the peroxyhydrate, which would otherwise escape unused as molecular oxygen, to be converted to singlet oxygen which plays an active role in bleaching the stains.

This invention also provides detergent compositions which are suitable for use in the bleaching process, and as stated earlier, comprise a peroxyhydrate, an alkaline detergent builder, a photoactivator, and an organic detergent. The proportions of peroxyhydrate, alkaline detergency builder and organic detergent are preferably those conventionally used in this type of detergent product, namely, from 5-50 percent of peroxyhydrate, from 5-60 percent of alkaline detergency builder and from 5-50 percent organic detergent, all by weight based on the weight of the total composition.

The compositions of the invention may be used for simultaneous washing and bleaching of textiles, and are particularly suitable for domestic laundry operations. It is suitable to carry out the bleaching or washing/- bleaching process out of doors in natural sunlight, as is customary in many countries with sunny climates, or it may be carried out in a washing machine which is equipped with means for illuminating the contents of the tub during the washing operation. Such a washing machine is the subject of a copending patent application U.S. Ser. No. 373,697 to Peter Roscoe Hartley Speakman, filed June 26, I973.

It has been found that a useful bleaching effect is obtained merely by soaking the fabrics for several hours for examples from 3-7 hours in a solution of the composition of the invention, indoors under the conditions of illumination, (natural daylight or artificial light) normally obtained indoors. Such soaking operations are normally succeeded by conventional washing of the fabrics.

What is claimed is:

l. A process for removing stains from textiles which comprises a. treating the textiles in the presence of oxygen with an aqueous liquor containing i. a concentration of from 0.2 to 2.0 grams per liter of organic detergent; ii. a concentration of from 0.2 to 2.0 grams per liter of alkaline detergency builder; and iii. a concentration of from 1 to mg. per liter of a photoactivator selected from the group consisting of eosin, rose bengal, fluoroscein, chlorophyll, metal-free porphyrin, sulfonated phthalocyanine, and sulfonated zinc phthalocyanine; and b. simultaneously irradiating the textiles with visible light which includes light of wavelength 640 nm and higher. 2. A process according to claim 1 in which the process takes place in the presence of atmospheric oxygen.

3. A process according to claim 2 in which the photoactivator is sulfonated zinc phthalocyanine which is substantially free of unsulfonated zinc phthalocyanine.

4. A process according to claim 3 in which the intensity of the visible light with which the textiles are irradiated is at least 1000 lumens, the temperature at which the process is carried out is from 80 to l60F., and the time in which the process is carried out is from minutes to 5 hours.

5. A process according to claim 4 in which the source of visible light is one or more incandescent tungsten filament electric bulbs.

6. A process according to claim 4 in which the source of visible light is sunlight.

7. A process according to claim 1 wherein the aqueous liquor contains a sufficient concentration of peroxyhydrate to supply from 0.02 to 2 gm. available oxygen per liter.

8. A process according to claim 7 in which the photoactivator is sulfonated zinc phthalocyanine which is substantially free of unsulfonated zinc phthalocyanine.

9. A process according to claim 8 in which the intensity of the visible light with which the textiles are irradiated is at least 1000 lumens, the temperature at which the process is carried out is from 80 to 160F., and the time in which the process is carried out is from l5 minutes to 5 hours.

10. A process according to claim 9 in which the source of visible light is one or more incandescent tengsten filament electric bulbs.

ll. A process according to claim 9 in which the source of visible light is sunlight.

12. A process according to claim 7 which is carried out as a soaking process under normal conditions of indoor illumination.

13. A process according to claim 7 in which the process takes place in the presence of atmospheric oxygen.

14. A detergent composition consisting essentially of, by weight of the composition, from 5 to 50 percent of an organic detergent, from S to 60 percent of an alkaline builder salt, and from 0.025 percent to 1.25 percent of a photoactivator selected from the group consisting of eosin, rose bengal, fluorescein, chlorophyll, metal-free porphyrin, sulfonated phthalocyanine and sulfonated zinc phthalocyanine.

15. A detergent composition according to claim 14 wherein the photoactivator is sulfonated zinc phthalocyanine substantially free of unsulfonated zinc phthalocyanine.

16. A detergent composition according to claim M which additionally contains, by weight of the composition, from 5 to 50 percent peroxyhydrate.

17. A detergent composition according to claim 16 wherein the photoactivator is sulfonated zinc phthalocyanine substantially free of unsulfonated zinc phthalocyanine.

18. A detergent composition according to claim 17 wherein the peroxyhydrate is selected from the group consisting of sodium perborate monohydrate and sodium perborate tetrahydrate.

Claims (18)

1. A PROCESS FOR REMOVING STAINS FROM TEXTILES WHICH COMPRISES A. TREATING THE TEXTILES IN THE PRESENCE OF OXYGEN WITH AN AQUEOUS LIQUOR CONTAINING I. A CONCENTRATION OF FROM 0.2 TO 2.0 GRAMS PER LITER OF ORGANIC DETERGENT; II. A CONCENTRATION OF FROM 0.2 TO 2.0 GRAMS PER LITER OF ALKALINE DETERGENCY BUILDER; AND III. A CONCENTRATION OF FROM 1 TO 50 MG. PER LITER OF A PHOTOACTIVATOR SELECTED FROM THE GROUP CONSISTING OF EOSIN, ROSE BENGAL, FLUOROSCEIN, CHLOROPHYLL, METAL-FREE PORPHYRIN, SULFONATED PHTHALOCYANINE, AND SULFONATED ZINC PHTHALOCYANINE; AND B. SIMULTANEOUSLY IRRADIATING THE TEXTILES WITH VISIBLE LIGHT WHICH INCLUDES LIGHT OF WAVELENGTH 640 NM AND HIGHER.

2. A process according to claim 1 in which the process takes place in the presence of atmospheric oxygen.

3. A process according to claim 2 in which the photoactivator is sulfonated zinc phthalocyanine which is substantially free of unsulfonated zinc phthalocyanine.

4. A process according to claim 3 in which the intensity of the visible light with which the textiles are irradiated is at least 1000 lumens, the temperature at which the process is carried out is from 80* to 160*F., and the time in which the process is carried out is from 15 minutes to 5 hours.

5. A process according to claim 4 in which the source of visible light is one or more incandescent tungsten filament electric bulbs.

6. A process according to claim 4 in which the souRce of visible light is sunlight.

7. A process according to claim 1 wherein the aqueous liquor contains a sufficient concentration of peroxyhydrate to supply from 0.02 to 2 gm. available oxygen per liter.

8. A process according to claim 7 in which the photoactivator is sulfonated zinc phthalocyanine which is substantially free of unsulfonated zinc phthalocyanine.

9. A process according to claim 8 in which the intensity of the visible light with which the textiles are irradiated is at least 1000 lumens, the temperature at which the process is carried out is from 80* to 160*F., and the time in which the process is carried out is from 15 minutes to 5 hours.

10. A process according to claim 9 in which the source of visible light is one or more incandescent tengsten filament electric bulbs.

11. A process according to claim 9 in which the source of visible light is sunlight.

12. A process according to claim 7 which is carried out as a soaking process under normal conditions of indoor illumination.

13. A process according to claim 7 in which the process takes place in the presence of atmospheric oxygen.

14. A detergent composition consisting essentially of, by weight of the composition, from 5 to 50 percent of an organic detergent, from 5 to 60 percent of an alkaline builder salt, and from 0.025 percent to 1.25 percent of a photoactivator selected from the group consisting of eosin, rose bengal, fluorescein, chlorophyll, metal-free porphyrin, sulfonated phthalocyanine and sulfonated zinc phthalocyanine.

15. A detergent composition according to claim 14 wherein the photoactivator is sulfonated zinc phthalocyanine substantially free of unsulfonated zinc phthalocyanine.

16. A detergent composition according to claim 14 which additionally contains, by weight of the composition, from 5 to 50 percent peroxyhydrate.

17. A detergent composition according to claim 16 wherein the photoactivator is sulfonated zinc phthalocyanine substantially free of unsulfonated zinc phthalocyanine.

18. A detergent composition according to claim 17 wherein the peroxyhydrate is selected from the group consisting of sodium perborate monohydrate and sodium perborate tetrahydrate.