MXPA99001524A

MXPA99001524A - Bleaching compositions

Info

Publication number: MXPA99001524A
Application number: MXPA/A/1999/001524A
Authority: MX
Inventors: Briatore Andrea; Scialla Stefano; Di Capua Gloria
Original assignee: The Procter&Ampgamble Company
Priority date: 1996-08-12
Filing date: 1999-02-12
Publication date: 1999-06-01

Abstract

The present invention relates to hypohalite bleaching compositions comprising a pH buffering component and an ingredient having the ability to prevent the precipitation of the salts of said buffering component upon dilution of the composition in water. Fabric whiteness as well as fabric safety are improved.

Description

BLEACHING COMPOSITIONS FIELD OF THE INVENTION The present invention relates to bleaching compositions, in particular to hypochlorite bleaching compositions suitable for use in laundry applications such as hand and machine washing methods.

BACKGROUND OF THE INVENTION Bleaching compositions are well known in the art. Among the different bleaching compositions available, those which are based on bleaching by hypohalogenite bleach such as hypochlorite are commonly preferred, mainly for performance reasons, especially at low temperatures. However, a problem encountered with the use of hypochlorite-based compositions is the resultant damage and / or yellowing of the fabrics that are bleached. Therefore, an object of the invention is to provide a composition containing hypohalogenite, suitable for use in laundry applications, which provides whiteness to the fabrics treated therewith. Another object of the invention is to provide a composition containing hypohalogenite, suitable for use in laundry applications, which provides security to the fabrics treated therewith. To meet these needs, pH regulating components such as silicates have been incorporated into the hypochlorite compositions. A typical description can be found in EP-A-0, 653, 483. The Applicant has now surprisingly discovered that this problem is solved by the use, in a hypohalogenite bleaching composition containing a pH regulating component, of an ingredient that it has the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water. In fact, it has been found that improved whiteness and / or fabric security was obtained with the composition of the invention compared to hypohalogenite compositions containing a pH regulating component but no ingredient having the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water. Another advantage of the compositions of the invention is that they are chemically stable. By the term "chemically stable" is meant that the hypohalogenite bleaching compositions of the present invention should not suffer a loss of more than 15% of the available chlorine after 5 days of storage at 50 ° C + 0.5 ° C. The% loss of available chlorine can be measured using the method described, for example, in "Analyzes des Eaux et Extraits de Javel" by "La chambre syndicale nationale de L'eau de Javel et des produits connexes", pgs. 9-10 (1984). Said method consists of measuring the available chlorine in the fresh compositions, that is, just after they are made, and in the same compositions after 5 days at 50 ° C. An additional advantage of the compositions of the invention is that they are suitable for bleaching different types of fabrics including natural fabrics (e.g., fabrics made of cotton, viscose, linen, silk and wool), synthetic fabrics such as those made of polymer fibers of synthetic origin, as well as those made of both natural and synthetic fibers. In fact, the compositions of the present invention can be used in synthetic fabrics despite a prevailing prejudice against the use of hypohalogenite bleach, especially hypochlorite bleach, in synthetic fabrics, as evidenced by the warnings on the labels of the commercially available hypochlorite bleach and clothing.

BRIEF DESCRIPTION OF THE INVENTION The present invention is a liquid bleaching composition comprising: a) a hypohalogenite bleach, b) a pH regulating component in an amount of 0.5% to 9% by weight, and c) an ingredient that has the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water; with the proviso that when said ingredient is a polyacrylate polymer, the polymer is present in an amount of less than 0.5% by weight. In another aspect of the invention, a solid bleaching composition is provided comprising: a) a hypohalogenite bleach, b) a pH regulating component, and c) an ingredient having the ability to prevent precipitation of the salts of said component. pH regulator after dilution of the composition in water. The present invention also encompasses a fabric bleaching process with a composition comprising: a) a hypohalogenite bleach, b) a pH regulating component in an amount of 0.5% to 9% by weight, and c) an ingredient having the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water; wherein said fabrics are immersed in a bleaching solution formed by diluting said composition in water. The present invention also encompasses the use, in a hypohalogenite bleaching composition comprising a pH regulating component, of an ingredient having the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition. in water, to provide improved whiteness and / or fabric security to the fabrics treated with it.

DETAILED DESCRIPTION OF THE INVENTION Hypohalocene Bleaching An essential component of the invention is a hypohalogenite bleach. Hypohalogenite bleaches can be provided by a variety of sources, including bleaches which are oxidants and which subsequently lead to the formation of positive halide ions, as well as bleaches which are sources of organic base halides such as chloroisocyanurates. Hypohalogenite whiteners suitable for use herein include hypochlorites, hypobromites, alkali metal and alkaline earth metal hypoiodides, chlorinated trisodium phosphate dodecahydrate, potassium and sodium dichloroisocyanurates, potassium and sodium trichloroisocyanurates, N-chloroimides, N -chloroamides, N-chloroamines and chlorohydantoins. For liquid compositions, the hypohalogenite bleaches which are preferred among those described above are the alkali metal and alkaline earth metal hypochlorites selected from the group consisting of sodium, potassium, magnesium, lithium and calcium hypochlorites, and mixtures thereof, most preferably alkali metal sodium hypochlorite. For solid compositions, the hypohalogenite bleaches which are preferred among those described above are the alkali metal and alkaline earth metal hypochlorites selected from the group consisting of lithium hypochlorites, calcium hypochlorites, chlorinated trisodium phosphate dodecahydrate, potassium dichloroisocyanurates, dichloroisocyanurates of sodium, potassium trichloroisocyanurates, trichloroisocyanurates and mixtures thereof, most preferably sodium dichloroisocyanurates and / or calcium hypochlorite. Preferably, the liquid compositions according to the present invention comprise said hypohalogenite bleach so that the content of active halide in the composition is from 0.1% to 20% by weight, preferably from 2% to 8% by weight, most preferably 3% by weight. % to 6% by weight of the composition. Preferably, the solid compositions according to the present invention comprise said hypohalogenite bleach so that the content of active halide in the composition is from 20% to 95% by weight, preferably from 25% to 60% by weight of the composition.

PH regulator component A pH regulator component is another essential component of the compositions of the invention. The pH regulating component ensures that the pH of the composition is regulated at a pH value ranging from 7.5 to 13, preferably from 8 to 12, most preferably from 8.5 to 11.5, after the composition has been diluted 1 to 500 times its weight in water. The pH adjusting components suitable for use herein are selected from the group consisting of alkali metal salts of carbonates, polycarbonates, sesquicarbonates, silicates, polysilicates, borates, metaborates, phosphates, stannates, aluminates and mixtures thereof, and preferably they are selected from the group consisting of sodium carbonate, sodium silicate, sodium borate, and mixtures thereof. The raw materials involved in the preparation of hypohalogenite bleach typically contain byproducts, e.g., calcium carbonate, resulting in an amount of up to 0.4% by weight of by-product in the hypohalogenite composition. However, in such quantity, the by-product will not have the pH-regulating action defined above. The liquid bleach compositions herein will contain an amount of pH adjusting component from 0.5% to 9% by weight, preferably from 0.5% to 5% by weight, and most preferably in an amount from 0.6% to 3% by weight of the composition. The solid bleaching compositions herein will preferably contain an amount of pH regulating component of 3% to 30% by weight, preferably 5% to 25% by weight, and most preferably in an amount of 10% to 20% by weight of the composition.

Ingredient that has the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water The other essential component of the invention is an ingredient that has the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water. It has been surprisingly discovered that that ingredient, by avoiding the precipitation of the salts of said pH regulating component after dilution of the composition in water, provides a reduction of the yellowing of the fabrics treated therewith, that is, improved whiteness, as well as providing a safety of Improved fabrics. Naturally, for the purposes of the invention, the ingredient having the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water has to be stable with hypohalogenite bleach. The ability of an ingredient to prevent precipitation of the salts of the pH regulating component after dilution of the composition in water can be measured by means of the following comparative test: A composition containing 5% by weight of sodium hypochlorite is prepared , 1.4% by weight of sodium hydroxide, 1.5% by weight of sodium carbonate and water (between 10 ° F and 40 ° F (French degrees)) up to a balance of 100% by weight. 10 ml of this composition is added to 1 liter of tap water (30 ° F (French degrees)). The solution is maintained at 40 ° C for 30 minutes. The formed precipitates are separated from said solution and then dried and weighed. By "separating the formed precipitates", it is attempted to filter said solution with an apparatus comprising a peristatic pump, a vacuum flask and a filter with a porosity of 0.45 microns. The above test is repeated with the same composition formulation but with the exception that 0.05% by weight of the ingredient to be tested is added to the composition. The ingredients that have the ability to prevent precipitation of the salts of the pH regulating component after dilution of the composition in water will reduce the amount of the precipitates formed, as measured by this method, by more than 50% compared to the same compositions that do not contain the ingredient having the ability to prevent precipitation of the salts of the pH regulating component after dilution of the composition in water. Preferred ingredients, for the purpose of the invention, are those that substantially maintain their ability to prevent precipitation of the salts of said pH regulating component, as defined above, after dilution of the composition in water and after of storage in an oven as defined in the following oven test method: The two compositions defined in the above test method are stored in an oven (Memmert) at 50 ° C for 7 days. After storage, the above test method is repeated, that is, for each composition 10 ml of the composition are taken and added to 1 liter of tap water. (30 ° F (French degrees)). The solution is maintained at 40 ° C for 30 minutes. The formed precipitates are separated from said solution and then dried and weighed. The compositions can also be tested to determine their effect of whiteness and / or safety on the treated fabrics. The bleaching effect, ie, the yellowing prevention effect and / or the security effect of the present invention can be evaluated by comparing the composition according to the present invention with the same composition without the ingredient having the ability to avoid precipitation of the salts of said pH regulating component after dilution of the composition in water. The degree of yellowing can be determined by both visual and instrumental grading.

Visually, the difference in yellowing between articles treated with different compositions can be determined by a team of expert panelists.

Instrumentally, the determination can be made with the help of colorimeters such as Ganz Griesser ^ instruments (e.g.

Datacolor® Spectraflash® SF 500, Machbet White-eye® 500) or a ZEISS ELREPHO or others that are available for example from HunterlabP or GardnerP. The safety of the fabrics can be evaluated by different test methods that include the polymerization degree test method according to the official UNI method (Ente Nazionale Italiano di Unificazione) UNI 8282-Determinazione della viscositá intrinsic in soluzione di cuprietilendiammina (CED ). The preferred ingredients that prevent precipitation of the salts of the pH regulating component after dilution of the composition in water are of the polymeric type. Polymers suitable for use herein and which prevent the precipitation of the salts of the pH regulating component after dilution of the composition in water are polymers comprising monomer units selected from the group consisting of unsaturated carboxylic acids, polycarboxylic acids, acids sulfonic acids, phosphonic acids and mixtures thereof. Copolymerization of the above monomeric units among themselves or with other comonomers such as styrenesulfonic acid is also suitable. Preferred examples of polymers which prevent precipitation of the salts of the pH-regulating component after dilution of the composition in water are the polymers and copolymers of monomeric units selected from the group consisting of acrylic acid, maleic acid, vinylsulfonic acid and mixtures of the same. Also suitable for use herein are the polymers and copolymers mentioned above, which are modified to contain other functional groups such as aminophosphonic and / or phosphonic units. The most preferred polymers are selected from the group consisting of polyacrylate polymers, copolymers of acrylic and maleic acid, copolymers of styrenesulfonic acid and maleic acid and mixtures thereof, preferably modified with aminophosphonic and / or phosphonic groups. The molecular weight for these polymers and copolymers is preferably less than 100,000, most preferably between 500 and 50,000. The most suitable polymers and copolymers for use herein will be soluble in an amount up to 0.1% by weight, in an aqueous composition comprising 5% by weight of sodium hypochlorite with its pH adjusted to 13 with sodium hydroxide. Commercially available polymers, suitable for use herein, which prevent precipitation of the salts of the pH-regulating component after dilution of the composition in water are the polyacrylate polymers sold under the tradename Good-Rite® from BF Goodrich. , Acrysol® from Rohm & Haas, SokalanR for BASF, NorasolR for Norso Haas. Also suitable for use herein are copolymers of styrenesulfonic acid and maleic acid, commercially available under the brand name Versaflex from National Starch such as Versaflex 157, as well as terpolymers.

Acumer P by Rohm and Haas, in particular AcumerP 3100. The commercially available polymers that are preferred are the polyacrylate polymers, especially the Norasol polyacrylate polymers and the Polyacrylate polymer Norasol® 410N (PM 10,000) and the polyacrylate polymer are most preferred. modified with phosphonic groups NorasolR 440N (PM 4000) and its corresponding acid form Norasol QR 784 (PM 4000). A polymer that is preferred to be used herein and still maintains its ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water and after storage in an oven as defined in the method of previous oven test is the polyacrylate polymer modified with phosphonic groups commercially available under the brand name Norasol 440N (PM 4000) and its corresponding acid form Norasol® QR 784 (PM 4000) from Norso-Haas. Mixtures of the polymers such as those described herein can also be used in the present invention.

The ingredient having the ability to prevent precipitation of the salts of the pH regulating component after dilution of the composition in water is preferably present in a low amount, ie, in an amount of up to 0.5% by weight, preferably 0.001% to 0.3% by weight, most preferably from 0.005% to 0.2% by weight of the liquid composition. The solid compositions of the invention will preferably comprise an amount of said ingredient from 0.01% to 3% by weight, preferably from 0.05% to 2% by weight of the composition. The compositions according to the present invention are in liquid or solid form. Solid forms include forms such as powders, tablets and granules. Preferably, the compositions of the invention are in liquid aqueous form. Also preferably, they comprise water in an amount of 60% to 98% by weight, most preferably 80% to 97% and more preferably 85% to 97% by weight of the aqueous liquid bleach composition. EH The pH of the liquid compositions according to the present invention, as such, is typically from 12 to 14 measured at 25 ° C. The solid compositions or liquid compositions of the invention have a pH of 7.5 to 13, preferably 8 to 12, most preferably 8.5 to 11.5, when diluted 1 to 500 times their weight in water. It is in this alkaline scale that optimum stability and performance of the hypohalogenite is obtained, as well as the whiteness and / or safety of fabrics. The pH scale is suitably provided by the pH regulating component and the hypohalogenite bleach mentioned hereinabove, which are alkalies. However, in addition to these components, a potent source of alkalinity can also be optionally used. Suitable alkalinity sources are caustic alkalies such as sodium hydroxide, potassium hydroxide and / or lithium hydroxide, and / or alkali metal oxides such as sodium and / or potassium oxide. A potent source of alkalinity that is preferred is a caustic alkali, most preferably sodium hydroxide and / or potassium hydroxide. Typical levels of said caustic alkalis, when present, are from 0.1% to 1.5% by weight, preferably from 0.5% to 1.5% by weight of the composition. The composition according to the invention may also comprise additional optional components such as perfumes, stable surfactants in the blanks, organic or inorganic alkalis, pigments, dyes, optical brighteners, solvents, chelating agents, radical scavengers and mixtures thereof. Preferably, the compositions of the invention are used in diluted form in laundry applications. The term "used in diluted form" includes dilution by the user, which occurs for example in laundry applications by hand, as well as dilution by other means, such as in a washing machine. Preferably, the composition is diluted in 5 to 500 times its weight of water for laundry applications by hand and in 10 to 500 times its weight in water in a washing machine. Thus, in another aspect of the invention there is provided a method for washing fabrics with a composition as described herein, wherein said fabrics are immersed in a bleaching solution formed by diluting said composition in water. In another aspect of the invention, the use is provided, in a hypohalogenite bleaching composition comprising a pH regulating component, of an ingredient having the ability to prevent precipitation of the salts of said pH regulating component after the dilution of the composition in water to provide improved whiteness and / or fabric security to the fabrics treated therewith. Accordingly, the present invention also encompasses the use, in a hypohalogenite bleaching composition comprising a pH regulating component, of an ingredient having the ability to prevent precipitation of the salts of said pH regulating component after dilution. of the composition in water to provide improved whiteness and / or fabric security to the fabrics treated therewith. By "improved whiteness and / or fabric security" is meant that the hypohalogenite bleaching compositions comprising a pH regulating component and an ingredient having the ability to prevent precipitation of the salts of said pH regulating component after the dilution of the composition in water, provide better whiteness, ie, less yellowing and / or fabric security compared to hypohalogenite bleaching compositions that do not comprise said ingredient. The invention is illustrated in the following non-limiting example, in which all percentages are on a weight basis unless otherwise indicated.

EXAMPLE 1 The following compositions were prepared according to the invention: EXAMPLE 2 The following compositions are in accordance with the present invention: Poly (vinyl sulfonic acid, sodium salt) available from Aldrich (CAS 25053-27-4)

Claims

NOVELTY OF THE INVENTION CLAIMS

1. - A liquid bleaching composition comprising: a) a hypohalogenite bleach, b) a pH regulating component in an amount of 0.5% to 9% by weight, and c) an ingredient that has the ability to prevent the precipitation of salts of said pH regulating component after dilution of the composition in water; with the proviso that when said ingredient is a polyacrylate polymer, the polymer is present in an amount of less than 0.5% by weight.

2. A solid bleaching composition comprising: a) a hypohalogenite bleach, b) a pH regulating component, and c) an ingredient having the ability to prevent precipitation of the salts of said pH regulating component after the dilution of the composition in water.

3. The use, in a hypohalogenite bleaching composition comprising a pH regulating component, of an ingredient having the ability to prevent precipitation of the salts of said pH regulating component after dilution of the composition in water , to provide improved whiteness and / or fabric security to the fabrics treated with it.

4. A fabric bleaching process with a composition comprising: a) a hypohalogenite bleach, b) a pH regulating component in an amount of 0.5% to 9% by weight, e) an ingredient having the capacity of avoiding precipitation of the salts of said pH regulating component after dilution of the composition in water; wherein said fabrics are immersed in a bleaching solution formed by diluting said composition in water.

5. A bleaching composition according to claim 1 or 2, use according to claim 3 or method according to claim 4, further characterized in that said ingredient is present in an amount of 0.001% to 0.5% by weight , preferably from 0.001% to 0.3%.

6. A bleaching composition, use or process according to any of claims 1-5, further characterized in that said ingredient is a polymer.

7. A bleaching composition, use or process according to claim 6, further characterized in that said polymer is selected from the group consisting of polyacrylate polymers, copolymers of acrylic and maleic acid, copolymers of styrenesulfonic acid and maleic acid and mixtures thereof.

8. A bleaching composition, use or process according to any of claims 6 or 7, further characterized in that said polymer has a molecular weight of less than 100,000.

9. A bleaching composition, use or process according to any of claims 6-8, further characterized in that said polymer is modified with aminophosphonic and / or phosphonic groups.

10. A bleaching composition, use or process according to any of claims 1-9, further characterized in that said pH regulating component is selected from the group consisting of alkali metal salts of carbonates, polycarbonates, sesquicarbonates, silicates, polysilicates, borates, metaborates, phosphates, stannates, aluminates and mixtures thereof.

11. A bleaching composition, use or process according to claim 10, further characterized in that said pH regulating component is selected from the group consisting of sodium carbonate, sodium silicates, sodium borate and mixtures thereof.

12. A bleaching composition, use or process according to any of claims 1-11, further characterized in that said pH regulating component is in an amount of 0.5% to 9% by weight, preferably 0.5% to 5% by weight of the liquid composition, or in an amount of 3% to 30% by weight, preferably 5% to 25% by weight of the solid composition.

13. A bleaching composition, use or method according to any of claims 1-12, further characterized in that said hypohalogenite bleach is, for liquid bleaching compositions, an alkali metal sodium hypochlorite or, for solid compositions, sodium dichloroisocyanurate and / or calcium hypochlorite.

14. A bleaching composition, use or process according to any of claims 1-13, further characterized in that said hypohalogenite, based on the active halide, is present in an amount of 0.1% to 20% by weight, preferably of 2% to 8% by weight of the liquid composition, or in an amount of 20% to 95% by weight, preferably 25% to 60% by weight of the solid composition.

15. A bleaching composition, use or process according to any of claims 1-14, further characterized in that said composition further comprises a strong source of alkalinity.