JPS6251320B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel detergent composition, particularly a novel detergent composition having soil redeposition prevention properties. It is known that when cleaning soiled fabrics using detergents, the phenomenon of soil redeposition often occurs, impairing the cleaning effect. this is,
Due to the action of the surfactant and builder contained in the cleaning agent, the dirt particles that are removed from the fabric and dispersed in the cleaning water are attracted again to the fabric surface by electrostatic attraction and are deposited. It is believed that this is for the purpose of This tendency is particularly noticeable in synthetic fibers such as polyester, which has been in increasing demand for clothing in recent years. Dirt that has redeposited on it cannot be removed even if it is washed again, and is the main cause of darkening of clothing. Solving this problem has become one of the challenges in cleaning agents. Until now, carboxymethylcellulose has been used as a soil redeposition prevention agent for cotton in the case of granular cleaning agents, and most granular cleaning agents currently on the market contain this. Also,
Water-soluble polymer compounds such as polyethylene glycol and polyvinylpyrrolidone are used as soil redeposition prevention agents for synthetic fibers, and polyethylene glycol is said to be particularly effective for polyester. By the way, these water-soluble polymer compounds have a common drawback of increasing biochemical oxygen demand (BOD) when collected as domestic wastewater at sewage treatment plants, so they are considered from the viewpoint of preventing environmental pollution. The amount added was limited. In order to prevent redeposition of dirt particles, it is necessary to use electrostatic repulsion to prevent dirt particles dispersed in the washing water from being deposited again on the fabric.
Alternatively, a method can be considered in which the surface of the washed fabric is coated with another component to prevent stains from being redeposited onto the fabric, and the addition of carboxymethyl cellulose or polyethylene glycol mentioned above belongs to the former. However, until now, there has been no known cleaning composition that can coat the surface of fabrics to prevent redeposition of stains and provides sufficiently satisfactory results. The present inventors have conducted extensive research in order to overcome the drawbacks of these conventional cleaning compositions, prevent the re-deposition of dirt, and develop a granular composition that does not cause environmental pollution. The cation exchange capacity (hereinafter referred to as
It has been found that a mixture containing approximately 10 to 45 meq/100 g of clay (abbreviated as CEC) as a component has excellent effects. Addition of various clays for the purpose of fabric processing and treatment finishing has been done in the past, and bentonite is added to cleaning agents to add hardness components such as calcium ions and magnesium ions to the cleaning water. Use for removal (UK Patent No. 401413)
No. specification), smectite-type clay with a cation exchange capacity of 50meq/100g or more is blended into a cleaning agent to clean and soften fabrics at the same time (Japanese Patent Application Laid-Open No. 1989-49-
85102, 49-132104, etc.) are also known. However, these clays have an extremely high ability to capture calcium ions, so even after they adhere to the surface of washed fabrics in the form of flakes, they still capture calcium ions contained in dirt dispersed in the wash water. As a result of adsorption, this was rather unfavorable in terms of preventing redeposition of dirt. In contrast, the present inventors obtained the unexpected finding that clay with a low CEC is more effective in preventing soil redeposition, and based on this, improved the ability to prevent soil redeposition. They succeeded in developing a cleaning composition that The correlation between the dirt redeposition prevention effect and CEC is explained as follows. Analyzing the mechanism by which fabric darkens due to redeposition of dirt, we find that the organic components in the dirt are first deposited on the fabric, and then this acts as a binder and regenerates inorganic components such as carbon particles. It progresses in a way that causes deposition. Therefore, when a thin film of clay adheres to the surface of the fabric after washing, it is incorporated into the surfactant micelles and removes the organic components of the dirt dispersed in the water and the calcium ions that are always present therein. It will be fixed on the fabric again through the thread. In this case, if a clay with a high CEC is used, the ability to capture calcium ions will be stronger, which will promote redeposition of organic components, and if a clay with a significantly low CEC is used, this will cause a decrease in CEC. The impurities in the clay interfere with the formation of a thin film on the fabric surface, which not only causes the dirt redeposition prevention effect to be lost, but in some cases, the above impurities adhere to the fabric surface and reduce the cleaning power. This causes a decrease in the temperature. In contrast, CEC
Clay in the range of about 10 to 45meq/100g does not have a very strong ability to bond with calcium ions in organic components, and has a moderate balance with its ability to form a thin film in water, so it is sufficiently effective in preventing dirt redeposition. Demonstrated. Montmorillonite group clay with a CEC of approximately 10 to 45meq/100g has an excellent ability to prevent redeposition of stains, especially when tested using light at a wavelength around 550μm, which is a common method for measuring darkening on fabrics. If you go there, you'll know for sure. However, as the present inventors continued their research, they found that when fabrics were repeatedly washed with a cleaning agent containing the above-mentioned montmorillonite group clay, the darkening hardly increased, but the fabrics gradually took on a reddish tinge. I realized that. Usually, when reddish is added to white, the above-mentioned
Although the reflectance measured with light at a wavelength of 550 μm remains largely unchanged, it is clearly discernible when observed with the naked eye, so this increased redness of the fabric also has a negative impact on the appearance of the garment. Undesirable. The iron content in the clay is thought to be the cause of the fabric gradually becoming reddish, but this phenomenon cannot be prevented even if the iron content in the clay is almost completely removed. This confirmed that this was not due to the iron content in the clay. The inventors of the present invention have conducted further research to prevent the increase in redness of fabrics due to repeated use of such cleaning compositions, and have surprisingly found that CEC
It has been discovered that the object can be achieved by using montmorillonite group clay of 45 meq/100 g or more that has been appropriately treated with mineral acid, and based on this knowledge, the present invention has been accomplished. That is, the present invention provides: (a) at least one non-synthetic surfactant selected from anionic surfactants and nonionic surfactants, (b) detergent builder, and (c) belonging to the montmorillonite group of minerals. Cation exchange capacity 45meq/100g, mainly composed of clay minerals
The above clay is mixed with Al ₂ O ₃ components contained in it.
The present invention provides a cleaning composition containing as an essential component a modified clay that has been acid-treated until 10% or more and less than 35% of the clay is eluted. The non-synthetic synthetic anionic surfactants used in the detergent composition of the present invention include those used in ordinary fabric detergents, such as those having a carbon number of about 10 to about 16.
Alkali metal salt or magnesium salt of alkylbenzenesulfonic acid having an alkyl group, sodium alkyl sulfate having about 11 to about 18 carbon atoms, alkali metal salt or magnesium salt of α-olefin sulfonic acid having about 10 to about 20 carbon atoms, carbon number about 8
Mention may be made of alkali metal or magnesium salts of sulfuric esters of ethylene oxide adducts of higher alcohols having from about 22 carbon atoms, alkali metal or magnesium salts of alkanesulfonic acids having from about 10 to about 22 carbon atoms, or mixtures thereof. In addition, nonionic surfactants include those used in ordinary fabric cleaning agents, such as HLB such as polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene fatty acid ester, and polyoxyethylene sorbitan fatty acid ester. A range of about 8 to 18 is suitable. The amount of this non-synthetic synthetic surfactant is usually about 2 to 40% by weight, preferably about 10 to 30% by weight. In addition, since nonionic surfactants tend to prevent clay, which is mainly composed of minerals belonging to the montmorillonite mineral group, from dispersing into extremely thin particles in water, the amount of nonionic surfactants in the composition of the present invention is approximately Preferably it does not exceed 15% by weight. Inorganic and organic builders are used as detergent builders in the detergent composition of the present invention, and examples include those commonly used in detergents for fabrics. Examples include sodium or potassium salts of condensed phosphoric acids such as tripolyphosphoric acid, hexametaphosphoric acid, pyrophosphoric acid, sodium or potassium carbonate (soda ash), inorganic alkaline builders such as sodium or potassium silicate, or sodium or potassium polycarboxylate. Examples include organic alkaline builders such as sodium or potassium citrate, sodium nitriloacetate (NTA) or potassium, and these can be used alone or in combination. This builder functions to keep the cleaning solution alkaline, preferably in the pH range of about 8 to 11, and also prevents the anionic surfactant from bonding with calcium ions and magnesium ions in the cleaning solution. Dirt components that have separated from the fabric once in
In particular, it is useful for preventing the fixed particle components from being deposited on the fabric again and improving the fabric cleaning performance. At the same time, this builder promotes the dissolution and dispersion of clay, which is mainly composed of minerals of the montmorillonite group described below, in water. This builder is typically present in the compositions of the invention from about 5 to
It is blended in an amount of 60% by weight, preferably in the range of about 10 to 40% by weight. Next, the clay whose main component is a clay mineral belonging to the montmorillonite group minerals (hereinafter referred to as montmorillonite group clay), which is a raw material for the modified clay used in the composition of the present invention, is a phyllosilicate mineral with a three-layer structure. Among them, clay whose main component is a group of clay minerals (generally referred to as montmorillonite group minerals) consisting of montmorillonite, saponite, hectorite, nontronite, sauconite, etc. that exhibit swelling properties in water. In the present invention, in particular, the clay has a CEC of 45meq/
It is necessary to use 100g or more of raw material. Montmorillonite group clays with such properties are natural bentonites whose main components are sodium-montmorillonite and calcium-montmorillonite, or sabonite and hectorite, and are commonly called magnesium-montmorillonite or magnesium-bentonite. You can choose from among the clays available. Montmorillonite group clay is boiled with concentrated sulfuric acid to elute and remove all or most of the Al ₂ O ₃ layer of montmorillonite group minerals, and it is called "activated clay" and is widely used as a catalyst and a decolorizing agent for oils and fats. It is also known to be added to detergents.
However, such "activated clay" does not turn the fabric red, but it also does not exhibit the effect of preventing stain redeposition, and therefore cannot be used in the present invention. When montmorillonite group clay is treated with mineral acid,
It is known that first iron, CaO, etc. are eluted, then the Al ₂ O ₃ octahedron in the three-layer structure of montmorillonite group minerals is destroyed and Al ₂ O ₃ is eluted, and finally only SiO ₂ remains. It is being What is used in the present invention is 10% or more of the Al ₂ O ₃ component,
It is a modified clay that has been acid treated until less than 35% is leached. When the amount of Al ₂ O ₃ eluted exceeds 35%, the layered structure of the montmorillonite group minerals is destroyed and the redeposition prevention effect is lost. In addition, no effect of acid treatment was observed when elution was less than 10%. Note that even if montmorillonite group clays with a CEC of 45 meq/100 g or less are treated with an acid within the above range, there is no change in the phenomenon of reddening the fabric, so there is no point in treating the clay with an acid. As mentioned above, clay of 45meq/100g or more does not have the effect of preventing stain redeposition as it is, and instead promotes redeposition, whereas clay that has been acid-treated to within the above range , exhibits an excellent redeposition prevention effect, and the fabric does not take on a reddish tinge. When montmorillonite group clay is treated with acid, its
CEC is known to decrease. However, in the present invention, the acid-treated clay obtained
Even if CEC is lower than untreated clay, it is not necessarily
It does not need to be below 45meq/100g. Also
CEC is produced by thermally transforming clay of 45meq/100g or more.
Even if it is less than 45meq/100g, the same effect as the present invention cannot be obtained. Examples of mineral acids used in acid treatment include hydrochloric acid, sulfuric acid, and nitric acid. If a dilute acid is used and the reaction is carried out at a low temperature, the time required to elute Al ₂ O ₃ to the above range will be longer, whereas if a concentrated acid is used and the reaction is boiled under pressure in an autoclave, a short time will be sufficient. In the present invention, the modified clay is preferably blended into the cleaning composition in an amount of 1 to 30% by weight. Further, the modified clay used in the present invention preferably has a particle size of about 5 to 800 μm, and about 50 μm.
(Tyler standard sieve 270 mesh opening) ~
Particularly preferred is one with a mesh size of 500 μm (32 mesh opening). This clay may be present separately from the particles of other detergent components, i.e., surfactant components, builder components, etc., or as extremely fine particles within the particles of these detergent components. It may be present in a uniformly dispersed manner. The cleaning composition of the present invention is usually used in the form of granules. Generally, granular detergents are manufactured by dissolving surfactant components, builders, and additives in water to form a highly concentrated slurry, and then spray-drying the slurry. When montmorillonite group clay is directly blended into such a slurry, the clay exists as fine particles uniformly dispersed in the detergent particles. However, modified clay treated with acid within the above range also acts as a thickener, so the amount of clay that can be blended into a highly concentrated slurry in which detergent components are dissolved is practically normal based on the amount of water in the slurry. The limit is about 15% by weight, so if more modified clay is to be incorporated into a detergent, it must be added as separate particles as described above. The cleaning composition of the present invention can contain components commonly used in general cleaning compositions. These include, for example, cleaning aids such as sodium sulfate, fluorescent agents, dyes, enzymes, and the like. Of course, water can also be added. The cleaning composition of the present invention uses clay, which is inexpensive and free from environmental pollution problems, and has an excellent effect of preventing soil redeposition and also has a good cleaning effect. Furthermore, since clay can be added in large amounts, costs can be significantly reduced. Next, the present invention will be explained in more detail based on examples. In the present invention, all CEC values are measured using a measurement method using an ammonium acetate aqueous solution (Yutaka Watanabe,
“Clay Science” 1 (1), 23 (1961)). The redeposition rate and redness evaluation in each example were measured as follows. (1) Redeposition rate: Attach a 2.5g piece of test cloth to the collar of a shirt and wear it for 3 to 7 days to make a dirty collar cloth. 10 pieces of the above collar soiled cloth and 3 pieces of test cloth of the same size were added to 900 ml of 0.133% aqueous solution of detergent, and heated at 25°C using a Tergotometer.
Wash for 10 minutes at 120r.pm. After washing, remove only the dirty collar cloth, add 10 new dirty collar cloths, wash, and repeat the process 10 or 20 times.
After repeating the test several times, take out the test cloth and add 900ml
After rinsing the tergotometer twice with tap water at 25°C and 120 rpm for 3 minutes each time, and air drying in a room at about 20°C, the reflectance at 550 μm was measured, and the redeposition rate was calculated using the following formula. Redeposition rate [%] = (Reflectance of the test cloth before use) - (Reflectance of the test cloth after soil redeposition) / (Reflectance of the test cloth before use) × 100 As the test cloth, commercially available No. 60 cotton cloth and 75 denier polyester cloth (both plain woven cloth) were used. (2) Evaluation of the shade of redness: Among each group made up of test fabrics of the same type, the one with the deepest redness as a result of naked eye observation is rated 2.0, the lightest one is 0.0, and the one in between is rated 2.0. Let be 1.0. Using these criteria, 10 people scored all the test fabrics in each group by assigning one of the above numerical values, and the sum of the numerical values for each test fabric was averaged to obtain the score. Example 1 By dissolving all the specified ingredients in water to make a slurry of approximately 50% by weight, and spray drying this,
A cleaning composition having the following composition was prepared. Each modified clay used in this work was prepared by boiling each clay with 20% sulfuric acid, extracting the clay as appropriate during the treatment, quantifying the Al ₂ O ₃ in it, and starting the treatment when a predetermined amount was reached. Stopped, washed with water and dried. Ingredients Weight % *LAS-Na (NW346) 25 Sodium pyrophosphate 22 Sodium silicate 12 Sulfur salt 29 Water 8 Clay 4 *LAS-Na; Sodium linear alkylbenzenesulfonate Type of clay used and its CEC, cotton as test fabric Table 1 shows the test results when using .

【table】

[Table] Example 2 A detergent composition having the composition shown below was prepared by dry blending a predetermined amount of clay component into a spray-dried detergent. The modified clay used in this study was 80% treated with 18% hydrochloric acid.
It was processed at ℃. Component Weight % *AOS-Na (C ₁₆ , C ₁₈ ) 13 **AES-Na (C ₁₂ - ₁₅ , P = 2) 6 Polyoxyethylene alkyl ether 2 (C ₁₂ - ₁₅ , P = 10) Sodium nitriloacetate 15 Sodium silicate 8 Soda ash 12 Sulfur salt 9 Water 10 Clay 25 *AOS-Na; Sodium α-olefin sulfonate **AES-Na; Sodium alkyl ether sulfate The type and CEC of the clay used, and polyester as the test fabric. Table 2 shows the test results when cotton was used.

[Table] Example 3 A detergent composition having the composition shown below was prepared by dry blending a predetermined amount of clay component into a spray-dried detergent. The modified clay used here was boiled in an autoclave with 18% hydrochloric acid added. Ingredients Weight % *LAS-Na (MW346) 20 **AOS-Na (C ₁₆ , C ₁₈ ) 5 Sodium pyrophosphate 14 Sodium silicate 11 Soda ash 5 Dimethyldistearylammonium 1 Chloride Sulfate 23 Water 8 Clay 13 *LAS -Na: Sodium linear alkylbenzenesulfonate **AOS-Na: Sodium α-olefin sulfonate Table 3 shows the type and CEC of the clay used, and the test results when cotton was used as the test cloth.

[Table] Comparative Example When using a detergent in which the clay component of each of the compositions of Examples 1 to 3 was removed and replaced with the same amount of copper salt, the redeposition rate was 8 to 11% on cotton; For polyester it was 43-49%. In addition, when comparing the case of using CMC and PEG, which are often used as anti-redeposition agents, each of the clay components in Examples 1 to 3 was removed and the total amount was 2% by weight to be the same as the clay. CMC or PEG
The re-deposition rate when using a detergent in which #6000 and the residual sulfate was substituted was 2 to 5% for the combination of CMC and cotton, and 16 to 24% for the combination of PEG #6000 and polyester. Ta.

Claims (1)

[Claims] 1. (a) At least one non-synthetic synthetic surfactant selected from anionic surfactants and nonionic surfactants, (b) detergent builder, and (c) belonging to the montmorillonite group of minerals. Clay with a cation exchange capacity of 45meq/100g or more, which is mainly composed of clay minerals, and the Al ₂ O ₃ component contained therein is 10% or more and 35%
A cleaning composition containing as an essential component a modified clay that has been acid-treated until it is eluted. 2. The cleaning composition according to claim 1, containing 2 to 40% by weight of component (a), 5 to 60% by weight of component (b), and 1 to 30% by weight of component (c). 3. The cleaning composition according to claim 1 or 2, which is in granular form.