KR20000029973A - Bleaching compositions - Google Patents

Abstract

PURPOSE: A hypohalite-containing composition, suitable for use in laundry applications is provided, which gives improved fabric whiteness to fabrics treated therewith. CONSTITUTION: Hypohalite bleaching compositions comprise a pH buffering component of 0.5to 9 wt.% and an ingredient having the ability to prevent the precipitation of the salts of the buffering component upon dilution of the composition in water. Fabric whiteness as well as fabric safety are improved.

Description

Bleaching compositions

Bleaching compositions are known in the art. Among other bleaching compositions used, those which rely on bleaching with hypohalite, such as hypochlorite, are often preferred, mainly in terms of performance, especially in terms of low temperature performance.

However, a problem faced with the use of hypochlorite-based compositions is that which results in damage and / or sulfidation of the bleached fabrics.

It is therefore an object of the present invention to provide a hypochlorite containing composition suitable for use in laundry applications that provides improved fabric whiteness to the treated fabric.

It is another advantage of the present invention to provide a hypohalite containing composition suitable for use in laundry applications that provides improved fabric safety to the treated fabric.

To meet this need, pH buffering ingredients, such as silicates, have been incorporated into the hypochlorite composition. Typical disclosures can be found in EP-A-0,653,483.

Applicants have therefore now surprisingly found that this problem is solved by using hypohalite bleaching compositions containing a pH buffering component and a component having the ability to prevent precipitation of salts of the buffering component when the composition is diluted in water. Indeed, an improved fabric using the composition of the present invention as compared to a hypohalite composition that contains a pH buffering component but does not contain a component having the ability to interfere with the precipitation of salts of the buffering component when the composition is diluted in water It was found that whiteness and / or safety was obtained.

Another advantage of the compositions of the present invention is that they are chemically stable. By "chemically stable" it is meant that the hypohalite bleaching composition of the invention should not lose more than 15% of the usable chlorine after 5 days of storage at 50 ± 0.5 ° C. The percent loss of chlorine that can be used is described, for example, in the method "Analyses des Eaux et Extraits de Javel" by "La chambre syndicale nationale de L'eau de Javel et des produits connexes", pages 9-10 (1984). It can be measured using. The method consists of measuring the fresh composition, ie the composition immediately after preparation, and the usable chlorine in the same composition after 5 days at 50 ° C.

Another advantage of the compositions of the present invention is that they are made of natural fabrics (eg fabrics made of cotton, viscose, linen, silk and wool), synthetic fabrics, such as fabrics made of polymeric fibers of synthetic raw materials, and natural and Suitable for bleaching of different types of fabrics, including fabrics made of both synthetic fibers. Indeed, the compositions of the present invention can be used in synthetic fibers despite the current bias against the use of hypohalite bleach, in particular hypochlorite bleach, in synthetic fibers as indicated in commercially available hypochlorite bleach and labeling warnings on garments. have.

Summary of the Invention

The present invention relates to a composition comprising a) a hypohalite bleach, b) 0.5 to 9 weight percent of a pH buffer component, and c) the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water, provided that In the case of 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 comprising a) a hypohalite bleach, b) a pH buffer component, and c) a component having the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water This is provided.

The present invention also provides a composition comprising a) a hypohalite bleach, b) 0.5 to 9 weight percent of a pH buffer component, and c) a component having the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water. A method of bleaching a fabric using a method, wherein the fabric is impregnated with a bleach solution formed by diluting the composition with water.

The present invention also provides the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water to provide improved fabric whiteness and / or safety to the treated fabric in a hypohalite bleach composition comprising a pH buffer component. It includes the use of the component having.

The present invention relates to bleaching compositions, in particular hypochlorite bleaching compositions, suitable for use in laundry applications such as hand wash and machine wash methods.

Hypohalite bleach

An essential ingredient of the present invention is hypohalite bleach. The hypohalite bleach can be provided by a variety of raw materials including bleach which is an oxidative bleach and subsequently forms cationic halide ions, and bleach which is an organic raw material of halides such as chloroisocyanurate.

Hypohalite bleach suitable for use herein is alkali and alkaline earth metal hypochlorite, hypobromite, hypoiodite, fluorinated trisodium phosphate dodecahydrate, potassium and sodium dichloroisocyanurate, potassium and sodium triclo Rocyanurate, N-chloroimide, N-chloroamide, N-chloroamine and chlorohydantoin.

For liquid compositions, the preferred hypohalite bleach among those disclosed above is an alkali metal and / or alkaline earth metal hypochlorite selected from the group consisting of sodium, potassium, magnesium, lithium and calcium hypochloride and mixtures thereof, more preferably alkali Metal sodium hypochlorite.

For solid compositions, preferred hypohalite bleaches among those disclosed above are lithium hypochlorite, calcium hypochlorite, chlorided trisodium phosphate dodecahydrate, potassium dichloroisocyanurate, sodium dichloroisocyanurate, potassium trichlorocy Alkali metal and / or alkaline earth metal hypochlorite selected from the group consisting of anurates, sodium trichlorocyanurate and mixtures thereof, more preferably sodium dichloroisocyanurate and / or calcium hypochlorite.

Preferably, the liquid composition according to the invention is hypohalite such that the amount of active halide in the composition is from 0.1 to 20% by weight, more preferably from 2 to 8% by weight and most preferably from 3 to 6% by weight of the composition. Contains bleach.

Preferably the solid composition according to the invention comprises a hypohalite bleach such that the amount of active halide in the composition is from 20 to 95% by weight, more preferably from 25 to 60% by weight of the composition.

pH buffering ingredients

The pH buffer component is another essential ingredient for the compositions of the present invention. The pH buffer component ensures that the pH of the composition is buffered to a pH range of 7.5 to 13, preferably 8 to 12, more preferably 8.5 to 11.5 after the composition is diluted in 1 to 500 fold weight of water.

Suitable pH buffering components for use herein are selected from the group consisting of carbonates, polycarbonates, sesquicarbonates, silicates, polysilicates, borates, metaborates, phosphates, stannates, alkali metal salts of aluminates and mixtures thereof, preferably It is preferably selected from the group consisting of sodium carbonate, sodium silicate, sodium borate and mixtures thereof.

Raw materials included in the preparation of the hypohalite bleach generally contain up to 0.4% by weight of by-products, such as potassium carbonate, in the hypohalite composition. However, in this amount the by-products do not have the buffering action defined above.

The liquid bleaching compositions herein will contain a pH buffering component in an amount of 0.5 to 9 weight percent, preferably 0.5 to 5 weight percent, more preferably 0.6 to 3 weight percent of the composition.

The solid bleach composition herein will preferably contain a pH buffering component in an amount of from 3 to 30% by weight, more preferably from 5 to 25% by weight and most preferably from 10 to 20% by weight of the composition.

A component having the ability to prevent precipitation of salts of the buffer components when the composition is diluted in water

Another essential ingredient of the present invention is a component having the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water. By preventing the precipitation of salts of the buffer component when the composition is diluted in water, this component has been found to surprisingly provide a reduction in the yellowing of the treated fabric, ie improved whiteness, and improved fabric safety. Naturally, for the purposes of the present invention, a component having the ability to prevent precipitation of salts of the buffer components when the composition is diluted in water should be stable to hypohalite bleach.

The ability of a component to prevent precipitation of salts of the buffer component when the composition is diluted in water can be determined by the following comparative test:

A composition containing 5% by weight sodium hypochlorite, 1.4% by weight sodium hydroxide, 1.5% by weight potassium carbonate and water (10-40 ° F.) is prepared. 10 ml of this composition is added to 1 l of tap water (30 ° F.). The solution is kept at 40 ° C. for 30 minutes. The precipitate formed was separated from the solution, dried and weighed. "Separating formed precipitate" means filtering the solution using a device comprising a rectifying pump, a vacuum flask and a filter with 0.45 micron pores. The test was repeated with the same composition formulation except that 0.05% by weight of the test component was added to the composition. Components having the ability to prevent the precipitation of salts of the buffer component when the composition is diluted in water are compared to the same composition that does not contain components that have the ability to prevent the precipitation of salts of the buffer component when the composition is diluted in water. The amount of precipitate formed as measured in accordance with the invention will be reduced by at least 50%.

Preferred ingredients for the purposes of the present invention are those which, when stored in an oven as defined by the oven test method below, substantially maintain the ability to prevent the precipitation of salts of the buffer components as defined above when the composition is diluted in water. will be:

The two components defined in the test method are stored in an oven (trade name Memmert) at 50 ° C. for 7 days. After storage, the test method is repeated, ie 10 ml of the composition is taken for each composition and added to 1 l of tap water (30 ° F.). The solution is kept at 40 ° C. for 30 minutes. The precipitate formed is separated from the solution, dried and weighed.

The composition may also be evaluated for its whiteness effect and / or safety on the treated fabric.

The pure whiteness effect of the present invention, i.e. the anti-sulfation effect and / or the safety effect, is obtained by comparing the composition according to the present invention with the same composition without the component having the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water. Can be evaluated

Sulphide can be measured by visual and mechanical grades. Visually, the difference in the degree of sulfation between products treated with different compositions can be measured by a skilled panelist team. Mechanically, the Ganz Griesser instrument (e.g., Datacolor, Spectraflash SF 500, Machbet White-eye 500) or, for example, ZEISS Evaluation can be made with the aid of a colorimeter, such as ELREPHO or Hunterlab or Gardner.

Fabric stability can be assessed by different test methods, including the formality test according to UNI (Ente Nazionale Italiano di Unificazione), the official method of UNI 8282-Determianzione della viscosita intrinseca in soluzione di cuprietilendiammina (CED).

A preferred component that prevents precipitation of salts of the buffer component when the composition is diluted in water is a polymerizable form.

Suitable polymers for use herein to prevent precipitation of salts of buffer components when the composition is diluted in water include polymers comprising monomer units selected from the group consisting of unsaturated carboxylic acids, polycarboxylic acids, sulfonic acids, phosphonic acids, and mixtures thereof. to be. Of these, copolymers of monomeric units or other comonomers such as styrenesulfonic acid are also suitable.

Preferred examples of polymers which prevent the precipitation of salts of the buffer components when the composition is diluted in water are polymers and copolymers of monomer units selected from the group consisting of acrylic acid, maleic acid, vinylsulfonic acid and mixtures thereof. Also suitable for use herein are the aforementioned polymers and copolymers modified to contain other functional groups, such as aminophosphone units and / or phosphone units. More preferred polymers are selected from the group consisting of polyacrylate polymers, copolymers of acrylic acid and maleic acid, copolymers of styrene sulfonic acid and maleic acid and mixtures thereof, preferably modified with aminophosphone groups and / or phosphone groups. will be.

The molecular weight for these polymers and copolymers is preferably less than 100,000, most preferably 500 to 50,000. The most suitable polymers and copolymers for use herein are those which are dissolved in an amount of less than 0.1% by weight in an aqueous composition comprising 5% by weight sodium hypochlorite adjusted to pH 13 with sodium hydroxide.

Suitable polymers for use herein which prevent the precipitation of salts of buffering ingredients when the composition is diluted in water are available from BF Goodrich under the trade names Good-Rite, Rohm & Haas. Polyacrylic polymer commercially available under the tradename Acryso® from BASF, the trademark Sokalan from BASF and Norasol® from Norso Haas. Also suitable for use herein are the brand name Accurs terpolymers, especially accumulators from Rohm and Haas, as well as the brand name Versaflex from National Starch, such as Versaflex 157. Copolymers of styrene sulfonic acid and maleic acid available under 3100. Preferred available polymers are polyacrylate polymers, in particular Norasol polyacrylate polymers and more preferably polyacrylate polymer Norasol 410N (molecular weight 10,000) and phosphonic acid group Norasol 440N (molecular weight) Polyacrylate polymer modified with 4000) and the corresponding acid from norasol QR 784 (molecular weight 4000).

Preferred polymers for use herein, which, when stored in an oven as defined in the oven test method, still retain the ability to prevent precipitation of salts of the buffer components upon dilution of the composition with water, are from NorsoHaas. Polyacrylate polymer modified with a phosphone group available under the trade name Norasol 440N (molecular weight 4000) and its corresponding acid form Norasol QR 784.

Mixtures of polymers as described herein can also be used in the present invention.

Components having the ability to prevent precipitation of salts of the buffer components when the composition is diluted in water are preferably low content, i.e. less than 0.5% by weight, more preferably 0.001 to 0.3% by weight and most preferably 0.005 to 0.2% by weight of the liquid. Present in an amount of the composition.

The solid composition of the present invention will preferably comprise 0.01 to 3% by weight, preferably 0.05 to 2% by weight of the composition components.

The composition according to the invention is in liquid or solid form. Solid forms include such forms as powders, tablets and granules. Preferably, the composition of the present invention is in liquid aqueous form. More preferably they comprise 60 to 98%, more preferably 80 to 97% and most preferably 85 to 97% water by weight of the total aqueous liquid bleach composition.

pH

The pH of the liquid composition according to the invention is typically 12 to 14 at 25 ° C. The solid or liquid composition of the present invention has a pH of 7.5 to 13, preferably 8 to 12, more preferably 8.5 to 11.5 when diluted to 1 to 500 times the weight of water. Optimal stability and performance of hypohalite in this alkali range as well as fabric whiteness and / or safety are obtained. The pH range is suitably provided by the aforementioned hypohalite bleach which is a pH buffer component and an alkali. However, in addition to these components, strong alkali sources can also optionally be used.

Suitable alkali sources are caustic alkalis such as sodium hydroxide, potassium hydroxide and / or titanium hydroxide, and / or alkali metal oxides such as sodium oxide and / or potassium oxide. Preferred strong alkali sources are caustic alkalis, more preferably sodium hydroxide and / or potassium hydroxide. The composition is 0.1 to 1.5% by weight, preferably 0.5 to 1.5% by weight when a typical content of such caustic alkali is present.

The composition according to the invention may also comprise further optional ingredients such as perfumes, bleaching surfactants, organic alkalis, inorganic alkalis, pigments, dyes, optical brighteners, solvents, chelating agents, radical masking agents and mixtures thereof.

Preferably the composition of the invention is used in diluted form in laundry. The expression “used in dilute form” herein includes dilution by a user as well as dilution by other means, such as a washing machine, which occurs, for example, in hand laundry. Preferably the composition is diluted 5 to 500 times the weight of water for hand laundry and 10 to 500 times the weight of water in a washing machine. Thus, in another aspect of the invention, a method is provided for washing a fabric with a composition as disclosed herein, wherein the fabric is immersed in a bleach solution formed by diluting the composition with water.

In another aspect of the invention, to prevent precipitation of salts of the buffer component when the composition is diluted in water to provide improved whiteness and / or safety to fabrics treated with the hypohalite bleaching composition comprising a pH buffer component. It provides the use of ingredients having the ability. Accordingly, the present invention also provides a method for preventing precipitation of salts of buffer components when the composition is diluted in water to provide improved bleaching and / or safety for fabrics treated with hypohalite bleach compositions comprising a pH buffer component. The use of ingredients having the capacity. “Improved pure whiteness and / or safety” means that the hypohalite bleaching composition comprising a pH buffering component and a component having the ability to prevent precipitation of salts of the buffering component when the composition is diluted in water does not contain the component. It is meant to provide good whiteness, ie less sulfidation, and / or fabric safety compared to hypohalite bleach compositions.

The invention is illustrated in the following non-limiting examples, where all percentages are by weight unless otherwise indicated.

Example 1

According to the present invention, the following composition was prepared.

Composition (% by weight) One 2 3 4 5 6 7 8 Sodium hypochlorite 5.0 5.0 5.0 2.5 2.5 2.5 5.0 5.0 Sodium hydroxide 0.9 0.7 0.7 0.9 0.7 0.7 0.5 - Sodium carbonate 1.2 1.2 1.2 1.2 1.2 1.2 - 1.5 Sodium silicate - 0.5 - - 0.5 - - - m-sodium borate - - 1.0 - - 1.0 1.0 - Norasol QR 784 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Water and small amount for 100 equilibrium

Example 2

The following composition is in accordance with the present invention.

Composition (% by weight) 9 10 11 12 13 14 Sodium hypochlorite 5.0 5.0 5.0 2.5 2.5 2.5 Sodium hydroxide 0.7 0.7 0.7 0.9 0.7 0.7 Sodium carbonate 1.2 1.2 1.2 1.2 1.2 1.2 Sodium silicate 0.5 0.5 0.5 - 0.5 0.5 Norasol 410N 0.1 - - 0.1 - - Versaflex 157 - 0.1 - - - 0.1 PVSA ^* - - 0.1 - 0.1 - Water and small amount for 100 equilibrium Poly (vinylsulfonic acid, sodium salt) available from Aldrich (CAS 25053-27-4)

Claims (15)

a) hypohalite bleach, b) 0.5 to 9 weight percent pH buffer component, and c) a liquid comprising a component having the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water, provided that the component is present in an amount of less than 0.5% by weight if the component is a polyacrylate polymer Bleaching composition. a) hypohalite bleach, b) a pH buffer component, and c) a solid bleaching composition comprising a component having the ability to prevent precipitation of salts of the buffer components when the composition is diluted in water. Use of a component having the ability to prevent precipitation of salts of the buffer component when the composition is diluted in water to provide improved whiteness and / or safety to the treated fabric in a hypohalite bleach composition containing a pH buffer component. a) hypohalite bleach, b) 0.5 to 9 weight percent pH buffer component, and c) a method of bleaching a fabric using a composition comprising a component having the ability to prevent precipitation of salts of buffering components when the composition is diluted in water, wherein the fabric is subjected to a bleach solution formed by diluting the composition in water. How to be impregnated. The bleaching composition according to claim 1 or 2, the use of claim 3 or the method of claim 4, wherein the component is present in an amount of 0.001 to 0.5% by weight, preferably 0.001 to 0.3% by weight. The method according to any one of claims 1 to 5, Bleaching compositions, uses or methods wherein the component is a polymer. The method of claim 6, Bleaching composition, use or method, wherein the polymer is selected from the group consisting of polyacrylate polymers, copolymers of acrylic acid and maleic acid, copolymers of styrene sulfonic acid and maleic acid, and mixtures thereof. The method according to claim 6 or 7, Bleaching compositions, uses or methods in which the polymer has a molecular weight of less than 100,000. The method according to any one of claims 6 to 8, Bleaching compositions, uses or methods wherein the polymer is modified with aminophosphone groups and / or phosphone groups. The method according to any one of claims 1 to 9, Bleaching composition, use or method wherein the pH buffering component is selected from the group consisting of carbonates, polycarbonates, sesquicarbonates, silicates, polysilicates, borate, metaborate, phosphate, stannates, alkali metal salts of aluminates and mixtures thereof. The method of claim 10, Bleaching composition, use or method wherein the pH buffering component is selected from the group consisting of sodium carbonate, sodium silicate, sodium borate and mixtures thereof. The method according to any one of claims 1 to 11, Bleaching composition, use or method in which the pH buffer component is in an amount of 0.5 to 9% by weight, preferably 0.5 to 5% by weight or 3 to 30% by weight, preferably 5 to 25% by weight of the solid composition. The method according to any one of claims 1 to 12, Bleach composition, use or method wherein the hypohalite bleach is alkali metal sodium hypochlorite for liquid bleach compositions or sodium dichloroisocyanurate and / or calcium hypochlorite for solid compositions. The method according to any one of claims 1 to 13, Bleach compositions wherein the hypohalite based on active halides is present in an amount of from 0.1 to 20% by weight, preferably from 2 to 8% by weight or from 20 to 95% by weight of a solid composition, preferably from 25 to 60% by weight, Use or method. The method according to any one of claims 1 to 14, Bleaching composition, use or method, wherein the composition further comprises a strong alkali source.