SK169098A3 - Laundry bleaching with improved safety to fabrics - Google Patents

Abstract

The present invention relates to the bleaching of fabrics with hydroperoxides, whereby the loss of tensile strength in said fabrics is reduced.

Description

Use of hydroperoxide and method of bleaching and fabric processing

Technical field

The present invention relates to bleaching fabrics.

Bleaching compositions containing peroxide oxygen are described in fabric washing applications such as detergents, additives, or even pretreatment agents.

However, it is known to use peroxide bleaching compositions in laundering applications to improve stain / dirt removal that is otherwise difficult to remove from fabrics such as fats, coffee, tea, grass, mud and the like. However, we have found that the disadvantage of these peroxidic bleaching compositions is the possibility of fabric damage resulting in loss of tensile strength, especially when used in fabric pretreatment, i. when applied directly to the fabrics (undiluted) and allowed to act for a long time before washing these fabrics.

It is an object of the present invention to provide improved fabric protection during bleaching, in particular pretreatment thereof, wherein the compositions come into contact with the fabrics undiluted and remain in contact with them for a long time before washing.

BACKGROUND OF THE INVENTION

However, when bleaching fabrics with compositions containing peroxide oxygen, such as hydrogen peroxide, it has been found that the presence of metal ions such as copper and / or iron and / or manganese and / or chromium on the fabric surface and / or exposure to sunlight UV on fabrics, after being contacted with a peroxygen bleaching composition, it acts detrimentally by reducing the tensile strength of their fibers. It is believed that the presence of metal ions such as copper and / or iron and / or manganese and / or chromium on the fabric surface, in particular on cellulose fibers and / or exposure of the fibers to sunlight UV, catalyzes radical decomposition of a peroxide bleach such as hydrogen peroxide. It is also believed that a radical reaction occurs on the surface of the fabric in the development of free radicals resulting in a loss of tensile strength of the fabrics.

It has now been discovered that improved fabric protection can be achieved by providing a bleaching composition wherein the hydrogen peroxide is replaced with selected hydroperoxides as the bleaching agent, or mixtures thereof.

U.S. Patent No. 5,284,597 discloses a composition for treating soft surfaces, especially carpets, which includes, inter alia, an alkyl hydroperoxide. Mixtures do not harm colors.

US 3,574,519 discloses bleaching fabrics wherein the bleaching agent is an organic hydroperoxide. Organic hydroperoxides are said to be economically attractive. The patent does not discuss the problem of fabric protection.

BE 831.277 discloses bleaching textiles using a blend of bleach activators, one of which comes from the triazine hydroperoxide class. Triazine hydroperoxides are said to be potentially harmful due to color. The patent does not discuss the problem of fabric protection. U.S. Patent 3,753,915 discloses bleaching fabrics with a granular composition comprising hydroperoxide salts. The patent does not discuss the problem of fabric protection.

SUMMARY OF THE INVENTION

The present invention encompasses, in its broadest form, the use of hydroperoxides for bleaching fabrics and for reducing the decrease in tensile strength in said fabrics.

The present invention further provides methods for bleaching fabrics, starting from a liquid composition comprising a hydroperoxide. The methods include the step of contacting said fabrics with a liquid bleaching composition, undiluted or diluted, followed by rinsing said fabrics.

In a preferred embodiment of the invention, in which the fabrics are pretreated, the composition is applied to the fabrics undiluted and then washed in a normal wash cycle. The present invention, in its broadest form, includes the use of hydroperoxide as a bleaching agent in the bleaching process of fabrics, while limiting the tensile strength of said fabrics. In other words, the present invention is based on the discovery that fabric damage resulting in reduced tensile strength is limited if the same composition is used instead of the hydrogen peroxide-containing composition but the hydroperoxide-containing composition or the mixture of hydroperoxides for bleaching the fabrics. It is believed that the observed reduction in tissue damage is due to a much less reactivity of the free radicals released from hydroperoxides as compared to the reactivity of the radicals from hydrogen peroxide.

Furthermore, hydroperoxides are considered to have less effect on heavy metal contamination on fabric damage, probably due to the fact that complex formation with the presence of metal and peroxide molecule is much more difficult than hydrogen peroxide.

The tensile strength of fabrics can be measured by stretching the fabric until it breaks. The force required to rupture the fabric is the tensile strength and is measured on a tensile tester to capture the stress-strain dependence. Such a device is available from. INSTRON. The decrease in tensile strength is characterized by the difference between the tensile strength of the reference fabric, i. a fabric which has not undergone a bleaching process and tensile strength of the same fabric after bleaching. A zero decrease in tensile strength means that damage to the fabric was not observed.

The liquid compositions useful in the present invention comprise as a major essential element a hydroperoxide or a mixture of hydroperoxides as a bleaching agent. Suitable hydroperoxides for this purpose include alkyl hydroperoxides and organomineral hydroperoxides λ / suitable alkyl peroxides for use according to the invention correspond to the formula:

R — C — O — O — H 2

I

R wherein each R, R, R is independently a hydrogen atom or a hydrocarbon radical having a carbon number of 1 to 30. The hydrocarbon radical may be a linear or cyclic chain, straight or branched, saturated or unsaturated. Also, two R groups may be part of the same cyclic hydrocarbon. One or more R groups, in the above formula, may be a single or fused aromatic radical, an alkyl-aryl radical or a cycloalkyl-aryl radical.

All of the above R radicals may also be replaced by heteroatoms or heteroatom groups such as hydroperoxide groups (-00H), halogen atoms, hydroxy groups, nitrates, sulfonyl, nitro groups, ethers, carboxyl groups and esters. All of these groups may also be present as substituents at one or more positions of R radicals. Preferred alkyl hydroperoxides for said use are t-butyl hydroperoxide, cumene hydroperoxide, 2,2,4-trimethylpentyl-2-hydroperoxide, diisopropylbenzene monohydroperoxide, tert-amyl hydroperoxide and 2,5-dimethylhexane-2,5-dihydroperoxide.

Suitable organomineral hydroperoxides for use herein have the formula

RM (OOH) m τ * λ (CH) SnOOH, (CH) SiOOH, '3 * 3' to 5.0 Vy - where M is a metal atom such as Si, Sn, Ge or Sb and R is a radical, defined above as R1, R2, R3. For use herein are preferred organomineral hydroperoxides _{(CH3) 3SiOOH,} (CH.) CH SiOOH, (CH) SiOOH, (n-C H) SiOOH, (C _e H _{s) 3} Sb (OOH). Most preferred is (CH) SiOOH.

Typically, the compositions herein comprise from 0.01 preferably 0.015% to 4.0%, most preferably from 0.2% to 2.0 of the usable oxygen provided by said hydroperoxides. The compositions used in the present invention must be liquids. Liquid compositions used herein also include slurry compositions, and preferably liquid compositions herein, having a viscosity of from 5 cps to 10,000 cps, at a shear rate of 50 rpm and a temperature of 20 ° C. The compositions used herein are preferably aqueous. These aqueous compositions have a pH of from 2 to 11, preferably from 3 to 10, and most preferably from 3.5 to 9.5, at which optimum chemical stability has been observed. The pH of the copositions can be adjusted e.g. organic or inorganic acids or alkaline agents. The compositions used according to the present invention may further comprise any surfactant including nonionic, anionic, cationic, zwitterionic and / or amphoteric surfactants.

Accordingly, the compositions used in the present invention preferably comprise other nonionic surfactants or mixtures thereof. The compositions of the present invention typically contain from 0.1% to 50% by weight. said nonionic surfactant, or a mixture thereof, preferably from 0.3% to 30% and most preferably from 0.4% to 25%.

surfactant fatty alcohol, Existing catalogs

Suitable surfactants as used herein are fatty alcohol ethoxylates and / or propoxylates which are commercially available with various fatty alcohols of varying chain length and varying degrees of ethoxylation. However, the HLB values of such nonionic agents substantially depend on the chain length of the nature of the alkoxylation and the degree of alkoxylation. surfactants include a description of surfactants, including non-ionic ones, including their HLB values.

Suitable chemical processes for preparing surfactants for use in the present invention include condensation of the corresponding alcohols with alkylene oxide in suitable proportions. Such procedures are well known in the art and are described in detail in the literature. For alternative uses, a variety of suitable alkoxylated alcohols from various suppliers are commercially available.

Particularly suitable for said purposes are nonionic surfactants such as hydrophobic surfactants having an HLB (hydrophilic-lipophilic balance) value below 16, preferably below 15, more preferably below 12 and most preferably below 10. These hydrophobic surfactants have been found to have good degreasing properties.

Recommended hydrophobic nonionic surfactants for use in the compositions of the present invention are surfactants with an HLB value below 16, and are of the formula RO- (CH) (CH) H, wherein R is an alkyl chain of C to C or an alkylbenzene chain C to and wherein n + m is from 0 to 20 and n is from 0 to 20, preferably n + m is from 1 to 15 and n are from 0 to 10 Recommended R chains for use in the present invention are alkyl chains of C _q to C ₂₂ . According to the above suitable hydrophobic nonionic surfactants for purposes of this invention, Dobanol ^R 91-2.5 (HLB = 8.1; R is a mixture of alkyl chains of C _g and

C, n is 2.5 am is O), or Lutensol * TO3 (HLB = 8; R is alkyl chain C, n is 3 am is 0), or Lutensol ^R AO3 (HLB = 8;

R is a mixture of alkyl chains of C ₁₃ and C, n is 3 and m is 0), or Tergitol ^R 25L3 (HLB = 7.7; R is in the range of alkyl chains of C to C, n is 3 and m is 0), or Dobanol ^R 23-3 (HLB = 8.1; R is a mixture of alkyl chains of C and C, n is 3 and m is 0), or Dobanol ^R 23-2 (HLB = 6.2; R is a mixture of alkyl chains of C 12 and C, n is 2 am is 0), or Dobanol ^R 45-7 (HLB = 11.6; R is a mixture of C and C alkyl chains, n is 6.5 am is 0), or Dobanol ^R 25-7 (HLB = 12; R is a mixture of alkyl chains c and C, n is 7 and m is 0), Dobanol ^R 91-5 (HLB = 11.6; R is a mixture of alkyl chains Cq and C, n is 5 and m is 0), or Dobanol ^R 91- 6 (HLB = 12.5; R is a mixture of alkyl chains C8 and C, n is 6 and m is 0), or Dobanol * 91-8 (HLB = 13.7; R is a mixture of alkyl chains C8 and C, n is 8 and m is 0) or Dobanol ^R 91-10 (HLB = 14.2; R is a mixture of alkyl chains C 8 and C, n is 10 and m is 0), or a mixture thereof. Here recommended are Dobanol ^R 91-2.5, or Lutensol ”T03, or Lutensol” A03, or Tergitol ^R 25L3, or Dobanol ^R 23-3, or Dobanol ^H 23-2, or a mixture thereof. These Dobanol ^R surfactants are available from SHELL. Lutensol ^R surfactants are commercially available from BASF and Tergitol ^R from UNION CARBIDE.

Preferred compositions used herein further comprise anionic surfactants, or mixtures thereof. Said surfactants act as a wetting agent, i. in laundry applications, they soak stains on fabrics, especially hydrophilic fabrics, and thus assist the hydroperoxide in its bleaching action, thereby improving the washing process for bleachable stains. Further, anionic surfactants make it possible to achieve the formation of clear compositions even though said compositions comprise hydrophobic components such as hydrophobic surfactants. Typical compositions used herein comprise from 0.1% to 20% by weight. said anionic surfactant, or mixtures thereof, preferably from 0.2% to 15% and more preferably from 0.5% to 13%.

Particularly preferred for use herein are sulfonate or sulfate surfactants. As anionic surfactants, they are well known in the art and are widely used as commercial detergents. These anionic surfactants include the alkyl benzene sulfonates ^C e ^- C ₂₂ (LAS), alkyl sulfates, C ₀ -C ₂₂ (AS), unsaturated sulfates such as oleyl sulfate, alkyl alkoxy C C (AES) C -C alkyl alkoxy carboxylates. The neutralizing cation for anionic synthetic sulfonates and / or sulfates is represented by conventional types of cations that are widely used in detergent technology such as sodium, potassium or alkanolammonium. Preference is given here to an alkyl sulfate, especially an alkyl sulfate derived from coconut oil having 6 to 18 carbon atoms in the alkyl chain, preferably from 8 to 15, or mixtures thereof.

The compositions used herein may further comprise, as a highly preferred additive, an antifoaming agent such as 2-alkyl alkanols, or mixtures thereof. Particularly suitable for use in the present invention are 2-alkyl alkanols having 6 to 16 carbon atoms in the alkyl chain, preferably from 8 to 12, and having a terminal hydroxyl group, said alkyl chain being substituted at the -position by an alkyl of 1 to 10 carbon atoms, preferably with 2 to 8, and more preferably 3 to 6. Such suitable components are commercially available, e.g. in an Isofol ^R series such as Isofol ¹ * 12 (2-butyloctanol) or Isofol ^R 16 (hexyldecanol).

Typical compositions suitable for the present invention comprise from 0.05% to 2% by weight, based on the total weight of the composition, of the 2-alkyl alkanols, or mixtures thereof, preferably from 0.1% to 1.5%, and most preferably from 0% to 2%. 1% to 0.8%.

The compositions may further comprise a variety of other optional ingredients such as stabilizers, chelates, impurity suspensions, dye carriers, radical scavengers, solvents, brighteners, perfumes and colorants.

In the present invention, the liquid bleaching compositions containing hydroperoxide must be in contact with bleached fabrics. This can be achieved either at the so-called "so-called". a pretreatment method, wherein the compositions are applied undiluted to said fabrics, prior to rinsing the fabrics, or before washing and subsequent rinsing, or in a soaking process, wherein a water bath is first prepared from the liquid composition by diluting it. The fabrics are immersed in the bath and then rinsed in the bath before rinsing. In another direct wash method, the liquid composition is added to the surface of the wash solution prepared by dissolving or dispersing the wash detergent.

As discussed above, the composition for carrying out the above processes is in a liquid, but not solid or gaseous state.

In both cases, it is also essential that the fabrics be rinsed after they have been in contact with said composition and before said composition has completely dried.

However, it has been found that evaporation of water contributes to increasing the concentration of free radicals on the fabric surface and consequently to the growth of the chain reaction. It has also been noted that after the evaporation of water, when the liquid composition is allowed to dry on the surface of the fabrics, an autooxidation reaction begins. This autooxidation reaction produces peroxy radicals which may contribute to the degradation of cellulose. Thus, in the pretreatment process of soiled fabrics, when the fabrics are pretreated with liquid bleaching compositions containing peroxide oxygen, it contributes to the success of the process of the present invention, i.e. to reduce the decrease in tensile strength when the liquid composition is not allowed to dry on the fabric surface as described above.

In the pretreatment process, the process comprises applying said composition in undiluted form to said fabrics, or at least a contaminated portion thereof, followed by rinsing or washing followed by rinsing. In this method, undiluted compositions can be (optionally) treated on fabrics for 1 min. up to 1 hour prior to rinsing, or before washing and subsequent rinsing, provided that the compositions do not allow to dry on the fabric surface. For particularly stubborn stains, further scrubbing or brushing of said fabrics using a sponge or brush, or rubbing two pieces of fabric against each other may be used. In another method, generally referred to as a dipping process, the process comprises preparing a water bath by diluting said liquid composition to form a diluted composition, i. compositions containing from 0.0001% to 0.2%, preferably from 0.0002% to 0.02% of useful oxygen formed by said hydroperoxide. The fabrics are then contacted with a water bath containing the liquid composition and finally rinsed or washed first and then rinsed. Preferably, in another embodiment, the fabrics are immersed in a water bath containing the liquid composition, and also preferably allowed to soak in the bath for 30 minutes to 48 hours, preferably 1 hour to 24 hours.

In yet another method which can be considered as an alternative soaking method, generally referred to as laundry bleaching, the liquid composition is used as a so-called " bleach " washing additive. In this method, a water bath is formed by dissolving and dispersing conventional laundry detergents in water. The undiluted liquid composition is added to the water bath and the fabrics are then soaked in the bath containing the liquid composition. Finally, the fabrics are rinsed.

Depending on their final form, these compositions may be packaged in a variety of containers, including conventional bottles, or in bead, sponge, brush or nebulizer bottles.

The invention is further illustrated by the following examples.

DETAILED DESCRIPTION OF THE INVENTION

Example 1:

The liquid composition is prepared as follows:

Cumenhydroperoxide 10%

Dobanol 45.7 8.6%

Dobanol 45.7 6.4%

C12 alkyl sulfate 2%

Water and other components up to 100% pH = 4, treated with sulfuric acid

Example 2:

The following liquid composition is prepared as follows:

t-butyl hydroperoxide 10%

Dobanol 45.7 6.0%

Dobanol 23.6,5 6.0%

C25-AE2.5-S (ethoxylated alkyl sulfate) 6.0%

Water and other components up to 100% pH = 4, treated with sulfuric acid

In the bleach direct washing process, the composition is contacted with a water bath prepared by dissolving a conventional detergent in water. The fabrics are then soaked in a liquid bath detergent water bath and then rinsed. The composition can also be used in a pretreatment process wherein the fabric stains are poured on the fabric and left to act for 5 minutes, then the fabric is washed.

Example 3:

The following liquid composition is prepared as follows:

t-butyl hydroperoxide 5%

Dobanol 91.10 1.6%

Dobanol 23.3 1.5%

CIO AS 1.7%

Isofol 12 ^R 0.5%

Water and other components up to 100% pH = 4, treated with sulfuric acid

This composition can be used in a pretreatment process or in a bleaching direct wash method as described in Examples 1 and 2. It can also be used in a soaking process wherein 100 ml of the liquid composition is dissolved in 10 liters of water. The fabrics are soaked in this water bath containing the composition and allowed to soak for 24 hours. The fabrics are then optionally rinsed.

Example 4:

The liquid detergent is prepared as follows:

Cumene 10% Dobanol 23.3 8.6% Dobanol 45.7 6.4% C12 AS 2% Water and other components to 100

pH = 6, adjusted with sulfuric acid

This composition is used in a pretreatment process as described above.

Example 5:

The following composition is prepared as follows:

2,5-dimethylhexane-2, dihydroperoxide 5%

Dobanol 23.3 8.6%

Dobanol 45.7 6.4%

C25-2.5EO-S

Water and other ingredients up to 100% pH = 5, treated with sulfuric acid

This composition is used in a pretreatment process as described in the previous examples.

Claims (8)

PATENT CLAIMS Use of hydroperoxyde, for bleaching fabrics, according to the formula R R — C — O — O — H 2 I R or RM (OOH) xn n wherein each R ₁ , R ₂ , R ₃ is independently H or a hydrocarbon radical of 1 or 30 carbon atoms, characterized in that it limits the tensile strength of said fabrics. 2. A method for bleaching fabrics, comprising preparing a water bath by diluting a clean liquid composition comprising a hydroperoxide according to the formula: R I R — C — O — O — H 2 R or RM (OOH) m rx wherein R, R ₂ , R ₃ is independently, H or a hydrocarbon radical containing 1 to 30 carbon atoms, further contacting said fabrics with said aqueous bath comprising said liquid composition and subsequent rinsing, or washing and then rinsing said fabrics. 3. A method of pretreating fabrics, characterized in that said undiluted composition comprising a hydroperoxide according to the formula: R R — C — O — O — H 2 I R or R M (OOH) ItX ΓΊ where R ₁ , R ₂ , R ₃ , R is, independently, H or a hydrocarbon radical containing from 1 to 30 carbon atoms, on said fabrics, preferably only on their contaminated part, before rinsing said fabrics or for washing and then rinsing said fabrics. The use according to claim 1 or the method according to claim 2, characterized in that the fabrics are rinsed in said water bath containing said liquid composition for a period of from 30 minutes to 48 hours, preferably from 1 to 24 hours Use according to claim 1, or the method according to claim 2, characterized in that said aqueous bath is prepared by dissolving or dispersing conventional laundry detergents in water. Use or method according to the preceding claims, characterized in that said undiluted composition comprises from 0.02% to 2% of the usable oxygen formed by said hydroperoxide. Use or method according to the preceding claims, characterized in that the hydroperoxide is t-butyl hydroperoxide or cumene hydroperoxide or 2,5-dimethylhexane-2,5-dihydroperoxide or 2,4,4-trimethylpentyl-2-hydoproxide or diisopropylbenzene monohydroperoxide or tert. amyl hydroperoxide. Use and method according to the preceding claims, characterized in that said composition has a pH of from 3.5 to 9.5.