JPH0214939B2 - - Google Patents

Description

[Detailed description of the invention]

In the present invention, a carboxyl-modified acrylonitrile butadiene rubber latex (hereinafter referred to as NBR latex) is blended with acrylonitrile butadiene rubber latex (hereinafter referred to as NBR latex), and a sponge obtained from this mixed latex contains a specific quaternary ammonium. The present invention relates to an invention that imparts hydrophilicity and water absorption to an NBR sponge by adsorbing one or more types of tertiary amine salts (hereinafter abbreviated as cationic surfactants). Conventionally, polyvinyl acetal sponge, which is an open-cell porous material, is commercially available as a well-known porous material with high hydrophilicity and water absorption. However, the above-mentioned polyvinyl acetal sponge body has the disadvantage that it hardens and loses elasticity when dried. On the other hand, open-celled NBR sponges do not lose their elasticity and are flexible when dry, but have the disadvantage of poor water retention due to poor hydrophilicity and water absorption. Attempts have been made in the past to impart hydrophilicity and water absorption properties to NBR sponges, but they all have drawbacks for industrial use and cannot be said to be sufficient. For example, JP-A No. 51-38351 discloses that a polyvinyl acetal material having an OH group is cross-linked and polymerized in the cells of an open-cell sponge material such as NBR latex or polyurethane foam to provide hydrophilicity and water absorption. Although a method for producing a porous material with increased properties has been described, it uses an acetalization reaction, so it has drawbacks such as requiring a great deal of labor and time to remove excess monomer. In addition, JP-A-56-131638 describes a method of imparting hydrophilicity to NBR latex by adding fibroin powder, but the effect of improving hydrophilicity was not very noticeable, and the dispersibility of fibroin powder However, since the powder material is added, the flexibility, especially the soft feeling on the skin, is impaired, and the strength of the sponge is also reduced. JP-A-55-152727 describes a method of imparting hydrophilic water absorbency to NBR sponge by adsorbing a cationic surfactant. but,
Since this adsorption is simply physical adsorption, the cationic surfactant gradually becomes difficult to remove due to the nature of sponges, which are wrung out with water each time they are used, resulting in a decrease in hydrophilicity and water absorption.
Furthermore, it is desirable to further improve the initial hydrophilicity and water absorption properties of the product for sale on the market. In view of these circumstances, the present inventors believe that if a functional group that captures a cationic surfactant can be introduced into the NBR sponge, the hydrophilicity and water absorption properties of the NBR sponge can be dramatically improved, and the effect will last for a long time. As a result of intensive research on various additives, we found that carboxyl-modified NBR met this purpose, and unexpected results showed that the NBR sponge's ease of use (good touch to the skin)
The inventors have also found that the present invention can be improved at the same time, and based on this knowledge, they have completed the present invention. That is, the present invention provides 1 NBR, carboxyl-modified NBR, and general formula

【formula】

【formula】

【formula】

【formula】

[Formula] [However, in the formula, R ₁ , R ₂ , R ₃ and R ₄ are an alkyl group, a benzyl group, or a general formula

[Formula] (R' represents H or CH ₃ , m represents an integer from 1 to 30);
At least one of them is a lipophilic group (10 carbon atoms)
~22 straight-chain alkyl groups, branched alkyl groups, or alkyl groups having a functional group such as an unsaturated bond, benzene ring, hydroxyl group, ether bond, ester bond, or amide bond in the group, and the remainder is the number of carbon atoms. 1 to 3 alkyl groups or monohydroxyalkyl groups or benzyl groups or
R' is either H or CH ₃ and m is a polyoxyalkylene group of 1 to 30. X represents a halogen atom or an alkyl sulfate group having 1 to 2 carbon atoms. Y represents an inorganic acid or a lower fatty acid] A water-absorbing sponge body formed by blending one or more of quaternary ammonium salts and tertiary amine salts represented by An open-cell sponge body made by blending 0.5 to 20 parts by weight of carboxyl-modified NBR latex with the general formula

【formula】

【formula】

【formula】

【formula】

[Formula] [However, in the formula, R ₁ , R ₂ , R ₃ and R ₄ are an alkyl group, a benzyl group, or a general formula

[Method for measuring changes in water absorption of a sponge body over time]

The change in water absorption of the sponge body over time, shown in FIG. 1, was measured by the following method. Measure the weight of each sponge body in advance. Each of them was gently floated on water, and after 10, 20, 30, 60, 120, and 180 seconds, they were gently taken out and weighed to determine the water content per unit volume. From Fig. 1, the modified product by the method of the present invention is a single polyvinyl acetal sponge body, an untreated polyvinyl acetal sponge body,
In terms of water absorption, it is far superior to NBR sponges, sponges made of a simple NBR latex sponge that does not contain carboxyl-modified NBR treated with a cationic surfactant, and NBR sponges with fibroin powder added. I understand. From this, it is clear that the product has better performance than conventional products when used in industrial water-absorbing rolls, stamp materials, cosmetic puffs, etc. Furthermore, it is stated that the product according to the invention described in the above-mentioned Japanese Patent Application Laid-open No. 51-38351 has almost the same hydrophilicity and water absorbency as a single polyvinyl acetal sponge. It can be said that it is clearly superior. Figure 2 shows the change in water absorption of the sponge body over time, which was measured in the same manner as in Figure 1 after washing the sponge body with fresh tap water each time. As is clear from this, the water absorbency of a simple NBR latex sponge that does not contain carboxyl-modified NBR decreases to about 1/2 when washed with water, making it somewhat difficult to absorb water as a sponge for use with water. In contrast, it can be seen that the sponge of Example 1 maintains its initial performance. Next, Table 1 shows the antibacterial effect of the sponge body according to Example 1. For comparison, results are shown for an untreated NBR sponge body, a sponge body in which diisobutylphenoxyethoxyethyldimethylbenzyl ammonium chloride is adsorbed onto NBR latex that does not contain carboxyl-modified NBR, and a sponge body made of polyvinyl acetal alone. As is clear from Table 1, the sponge body according to the present invention has superior antibacterial activity and long-lasting antibacterial activity compared to the comparative example.

[Antibacterial activity test method]

The antibacterial effects shown in Table 1 were measured using the following method. The product according to Example 1, NBR sponge body, polyvinyl acetal single sponge body, 4 cm × 4 cm ×
Cut into 1 cm pieces and use each dried piece as a sample. Place absorbent cotton on a 20cm diameter glass shear.
Soak in enough water. For each sample, one is placed as is and the other is soaked with 10 ml of Henneberg medium diluted 1/2. One platinum loop of each of the three strains of Cladosporium, Penicillium, and Aspergillus, which had been isolated from the sponge body that had been discolored by mold, was treated with sterilized Lapisol (manufactured by NOF Corporation) water.
Spray the mixed foam water evenly onto the sample, cover with a lid, and culture in a constant temperature bath at 25°C. Observe the growth of bacteria after 4 weeks. Judgment is displayed in the following four stages. (−): No growth of bacteria is observed. (+): Bacterial growth is observed partially. (++): Significant bacterial growth is observed. (+++): Bacterial growth is observed on the entire surface. Examples 2 to 32 30g of each cationic surfactant listed in Table-2
Each product was obtained in exactly the same manner as in Example 1 except for using the following ingredients. The results are shown in Table-2. In addition, for comparison, the results obtained when the number of carbon atoms is 8, those where the number of alkylene oxides added is 36 or 42, and a cationic polymer are also listed.

【table】

【table】

【table】 Judgment is indicated by the symbol below.

[Table] Example 33 As a base, 18 parts by weight of carboxyl-modified NBR latex solids 40% (Nipole 1571 manufactured by Nippon Zeon) was mixed with 100 parts by weight NBR latex solids 66% (Nipole LX 531-B manufactured by Nippon Zeon). did
Using an NBR sponge body, immerse it in a solution (50°C) consisting of the following composition. Dioctadecyldimethylammonium chloride
20g Dodecylpyridinium chloride 20g Water 40 After 10 minutes, the substrate is uniformly impregnated with the above solution, taken out, washed with water, dehydrated, and dried to obtain a product.
This product does not harden when dry, is flexible, has excellent hydrophilicity, water absorption, and antibacterial properties, and has good affinity for both water-based and oil-based cosmetics as a cosmetic puff. It had good spreadability, was soft to the skin, and had a pleasant feeling of use. Furthermore, its hydrophilic, water-absorbing and antibacterial effects did not decrease at all even after washing 30 times. Example 34 As a base, 1 part by weight of carboxyl-modified NBR latex solid content 40% (Nipole 1571 manufactured by Nippon Zeon) was blended with 100 parts by weight of NBR latex solid content 66% (Nipole LX 531-B manufactured by Nippon Zeon).
Using an NBR sponge body, immerse it in a solution (50°C) consisting of the following composition. Dodecyltrimethylammonium chloride 20g Dodecyldimethylammonium chloride 20g Water 40 After 10 minutes, the substrate is uniformly impregnated with the above solution, taken out, washed with water, dehydrated, and dried to obtain a product.
This product does not harden when drying, is flexible, has excellent hydrophilic and water absorbing properties, and has antibacterial properties.It has a good affinity for both water-based and oil-based cosmetics as a cosmetic puff, and is a popular cosmetic product. It had good adhesion and spreadability, and was also soft to the skin and had a pleasant feeling of use. Furthermore, its hydrophilic, water-absorbing and antibacterial effects remained unchanged even after 30 washes.

[Brief explanation of drawings]

FIG. 1 shows the change over time in the amount of water absorbed by the sponge body. Curve A is an NBR sponge body containing carboxyl-modified NBR treated by the method of the present invention, Curve B
is just NBR that does not contain carboxyl-modified NBR
A sponge body treated with the same cationic surfactant as in the present invention, curve C is a sponge body made of polyvinyl acetal alone, curve D is a sponge body made of untreated NBR, and curve E is a sponge body made of NBR with 5 parts of fibroin powder added. , shows the change in water absorption over time. Figure 2 shows the change over time in the amount of water absorbed by the sponge body after washing it 30 times with fresh tap water each time.
Curve A is a NBR sponge containing carboxyl-modified NBR treated by the method of the present invention, and curve B is a simple NBR sponge containing no carboxyl-modified NBR treated with the same cationic surfactant as in the present invention.

Claims (1)

[Claims] 1 Acrylonitrile butadiene rubber, carboxyl-modified acrylonitrile butadiene rubber, and general formula [Formula] [Formula] [Formula] [Formula] [Formula] [However, in the formula, R ₁ , R ₂ , R ₃ and R ₄ is an alkyl group,
Represents either a benzyl group or a polyoxyalkylene group represented by the general formula [Formula] (R' represents H or CH ₃ , m represents an integer from 1 to 30), at least one of which is Lipophilic group (represents a linear alkyl group having 10 to 22 carbon atoms, a branched alkyl group, or an alkyl group having a functional group such as an unsaturated bond, benzene ring, hydroxyl group, ether bond, ester bond, or amide bond in the group) and the rest are alkyl groups having 1 to 3 carbon atoms, monohydroxyalkyl groups, benzyl groups, or R' is H or CH ₃ and m is 1 to 3.
Any of the 30 polyoxyalkylene groups.
X represents a halogen atom or an alkyl sulfate group having 1 to 2 carbon atoms. Y represents an inorganic acid or a lower fatty acid.] A water-absorbing sponge material containing one or more of quaternary ammonium salts and tertiary amine salts represented by the following. 2 Add 0.5 to 20 parts of carboxyl-modified acrylonitrile butadiene rubber latex to 100 parts by weight of acrylonitrile butadiene rubber latex.
An open cell sponge body formed by blending parts by weight with the general formula [Formula] [Formula] [Formula] [Formula] [Formula] [However, in the formula, R ₁ , R ₂ , R ₃ and R ₄ are alkyl groups,
Represents either a benzyl group or a polyoxyalkylene group represented by the general formula [Formula] (R' represents H or CH ₃ , m represents an integer from 1 to 30), at least one of which represents a parent group. An oily group (representing a straight-chain alkyl group having 10 to 22 carbon atoms, a branched alkyl group, or an alkyl group having a functional group such as an unsaturated bond, a benzene ring, a hydroxyl group, an ether bond, an ester bond, or an amide bond in the group) The rest are alkyl groups with 1 to 3 carbon atoms, monohydroxyalkyl groups, benzyl groups, or R' is H or CH ₃ and m is 1 to 3.
Any of the 30 polyoxyalkylene groups.
X represents a halogen atom or an alkyl sulfate group having 1 to 2 carbon atoms. Y represents an inorganic acid or a lower fatty acid. A method for producing a water-absorbing sponge body, which comprises saturated adsorption of one or more tertiary amine salts, followed by pulling the sponge body out of the solution and drying it.