JP2776959B2 - Paint formulation - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a paint compounding liquid used for surface finishing of leathers such as PVC leather, synthetic leather, artificial leather, natural leather, and the like, or surface finishing of molded resin, metal, woodwork, etc. The present invention relates to a coating composition liquid used when performing, especially, a coating composition that provides a touch feeling rich in natural skin, has functionality such as moisture permeability, and provides a coating film with excellent mechanical strength. It concerns liquids.

[Prior art] Conventionally, many paints have been used as finishing paints for leathers, synthetic resin molded products, metal molded products, woodwork products, etc.
In particular, synthetic resin paints are functionally selected and used depending on the intended use. However, when a person directly touches the skin,
In the field of contact and use, when the skin comes into contact with the skin, there is no uncomfortable feeling, no stickiness due to sweat, and high moisture permeability, high moisture absorption, high moisture release paint film. Is desired. As an example of this, a leather powder dispersed in a synthetic resin paint such as polyurethane or vinyl chloride has been proposed. Also, if the content of the leather powder is too large, the surface feel is good but the strength is small, and there are disadvantages such as the leather powder falling off from the coating film when rubbing, and it is not satisfactory. Absent. The inventor of the present invention has completed the present invention as a result of intensive studies on paints that can provide a coating film that does not feel uncomfortable with human skin that is not satisfied by these conventional methods.

[Structure and Effect of the Invention] That is, the present invention is a coating composition comprising a dispersion of synthetic polyamino acid particles dispersed in an organic solvent solution of a synthetic resin mainly composed of a polyamino acid urethane resin. In the present invention, the polyamino acid urethane is a copolymer of a polyurethane and a polyamino acid, and a conventionally known polyamino acid urethane can be used. As a general method for producing a polyamino acid urethane, there is a method in which an N-carboxy-α-amino acid anhydride is addition-polymerized to a polyurethane. As the polyurethane used here, all conventionally known polyurethanes can be used. For example, a polyurethane obtained by reacting an organic diisocyanate with a long-chain diol, and a chain extender is typical.As the organic diisocyanate, an alicyclic organic diisocyanate, an aliphatic organic diisocyanate, an aromatic organic diisocyanate, or the like can be used. As long-chain diols, polyester diols, polyether diols, polyamide ester diols, polycarbonate diols and the like can be used, and as chain extenders, activities of low molecular glycols, low molecular diamines, low molecular amino alcohols and the like can be used. A compound containing two hydrogen atoms can be used, and a polyurethane composed of a mixture of these compounds may be used. Depending on the application, these materials should be selected, for example,
In applications where hydrolysis resistance is required and discoloration resistance is required, an alicyclic diisocyanate or an aliphatic diisocyanate is used as the organic diisocyanate, and a polycarbonate diol or poly is used as the long-chain diol. An ether diol may be used.

Examples of the N-carboxy-α-amino acid anhydride to be subjected to the addition reaction to the polyurethane include an anhydride of γ-methyl-L-glutamate and an anhydride of a carboxylic acid at the γ-position such as ethyl, propyl and butyl ester. Or leucine anhydride. The polyamino acid segment ratio in the polyamino acid urethane obtained by these reactions is 3% by weight to 85% by weight, preferably 10% by weight to 60% by weight. If the polyamino acid segment ratio is less than 3% by weight, the synthetic polyamino acid particles fall off the coating film, or the functional properties such as moisture permeability cannot be satisfied. It is not preferable because it cannot be performed. On the other hand, if the polyamino acid segment ratio exceeds 85% by weight, the resulting coating film has low elongation, and the mechanical strength against bending, rubbing, etc., is not preferred. The polyamino acid urethane thus obtained is used as an organic solvent solution. Examples of the organic solvent for dissolving the polyamino acid urethane include methylene chloride, chloroform, and chlorinated aliphatic hydrocarbons such as 1,2-dichloroethane, but when the polyurethane segment ratio in the polyamino acid urethane is high, it is difficult to dissolve, Moreover, it is better to avoid as much as possible from the viewpoint of hygiene. Preferred organic solvents include dioxane, N, N-dimethylformamide, N, N-
There are polar organic solvents such as dimethylacetamide, N-methylpyrrolidone, methyl ethyl ketone and tetrahydrofuran. When the organic solvent used is such a polar organic solvent, when the ratio of the amino acid segments of the polyamino acid urethane is 40% or more, it generally tends to become a translucent gel without being dissolved. Therefore, the amino acid segment ratio should be designed in consideration of the type of organic solvent used, the concentration used, and the like. In the present invention, in the organic solvent solution of the polyamino acid urethane thus obtained, in order to modify the properties of the obtained coating film, another synthetic resin or a natural resin is mixed and used. be able to. Also in this case, it is naturally preferable that the polyamino acid segment ratio in the mixed resin is 3% by weight to 85% by weight.

Synthetic polyamino acid particles dispersed in an organic solvent solution of a synthetic resin containing the above-described polyamino acid urethane as a main component are obtained by the method of addition-polymerizing an N-carboxy-α-amino acid anhydride described in detail above. Of the obtained polymer. It is a particulate polymer obtained by a method of addition polymerization of an N-carboxy-α-amino acid anhydride. N-
As the carboxy-α-amino acid anhydride, for example, γ-
Examples of the anhydride include methyl-L-glutamate, and anhydrides such as ethyl, propyl and butyl esters of carboxylic acid at the γ-position, and leucine. There are many literatures on these polymerization methods in the past, such as Polymer, 30,365 (1973), Polymer, 30,39 (1973), and Polymer, 30,357 (1973), which can be obtained by conventionally known methods. Polymer particles can be used in the present invention. By applying a mechanical force such as cutting or crushing to the gel obtained by these reactions, it is possible to transform the gel into α → β type to obtain particles that do not dissolve. The synthetic polyamino acid particles thus obtained are optionally subjected to a treatment such as pulverization in order to make the particles finer. The smaller the particle size, the larger the particle surface area per unit weight, and the more easily the resulting coating film will have functional properties such as moisture permeability, hygroscopicity, and moisture release, and the coating film will have a smoother surface feel. preferable. The average particle size of the particles is preferably 20 μm or less, more preferably 10 μm or less. The thus-obtained synthetic polyamino acid particles are added and dispersed in the above-described organic solvent solution of the polyamino acid urethane to obtain a dispersion coating liquid composition intended for the present invention.

(Effect of the Invention) A coating film formed of a resin containing polyamino acid urethane obtained as described above and a coating composition obtained from synthetic polyamino acid particles is subjected to mechanical force such as bending and kneading. However, since the polyamino acid segment of amino acid urethane having high elongation and excellent mechanical strength has affinity with the synthetic polyamino acid particles, neither whitening nor dropping of the synthetic polyamino acid particles occurs. Therefore, the amount of the synthetic polyamino acid particles added to the polyamino acid urethane (solid) can be widely selected. The amount of polyamino acid urethane and polyamino acid segments of the synthetic polyamino acid particles in the total solid content greatly affects the surface touch and functional properties of the resulting coating film. By doing so, a coating film rich in functional characteristics with a large amount of polyamino acid segments can be obtained. That is, when the synthetic polyamino acid particles are dispersed in an organic solvent solution of another polymer such as polyurethane without using the polyamino acid urethane, the amount of the polyamino acid segment in the coating film is relatively small with respect to the present invention. Therefore, it is difficult to obtain a coating film rich in the functional characteristics aimed at by the present invention. Further, the coating film obtained from only the organic solvent solution of polyamino acid urethane, when the polyamino acid segment ratio is large, a coating film rich in functionality intended for the present invention is obtained, but the elongation is small. Since it becomes a coating film, mechanical durability such as bending is inferior, and the object of the present invention cannot be achieved. As described above, the present invention is a formulation comprising a dispersion liquid for obtaining a functional film having a large polyamino acid segment ratio consisting of a molecular polyamino acid segment and a particulate polyamino acid segment, The coating film obtained from the compounding liquid has excellent mechanical strength. The weight of the polyamino acid segment obtained by summing the polyamino acid segment and the synthetic polyamino acid particles in the polyamino acid urethane constituting the liquid mixture of the present invention is preferably 20% by weight or more, more preferably 40% by weight, based on the total solid content. % Or more. However, these numerical values do not limit the present invention.

In some cases, by adding a coloring agent such as a pigment or a dye to the thus obtained coating composition, the cosmetic properties of the coating film obtained can be enhanced. Also,
An antioxidant, an anti-NOx gas discoloration inhibitor, various deterioration inhibitors and the like can also be added to obtain a good coating film.

The coating composition of the present invention obtained as described above is applied as a finish coating on the surface of leather, synthetic resin molded product, metal molded product, woodwork product and the like. As a coating method, conventionally known methods such as spray coating, gravure coating, knife coating, roll coating, and lamination using release paper can be employed. The concentration may be adjusted so as to obtain an optimum viscosity according to these coating methods. In one application. When the coating thickness is insufficient, the coating and drying may be repeated to adjust the coating thickness to a target value. The coating film thus obtained has a surface feel that is comfortable when a person comes into direct contact with the skin, and there is no stickiness due to sweat,
In addition, it has high moisture permeability, high moisture absorption, and high moisture release, and has high strength so that powder does not fall off even when rubbed.

EXAMPLES Hereinafter, the present invention will be described in detail with reference to examples. In the examples, “parts” and “%” are based on weight, and the characteristic measured values are obtained by the following methods.

(B) Moisture permeability According to the method of JIS L1099 A-1 method, moisture permeability (g / m ²
day).

(B) Moisture absorption Moisture absorption (g / m ² ) when left for 1 hour in an atmosphere at a temperature of 23 ° C and a relative humidity of 30%, and then left for 30 minutes in an atmosphere at a temperature of 23 ° C and a relative humidity of 80%. Expressed by

(C) Humidity release After leaving for 1 hour in an atmosphere at a temperature of 23 ° C. and a relative humidity of 80%, the amount of moisture release after leaving for 30 minutes in an atmosphere of a temperature of 23 ° C. and a relative humidity of 30% (g / m ²⁾ ).

(D) Flex resistance According to the method of JIS K6545 method, it is expressed in 1 to 5 class.

Example 1 (Preparation of Artificial Leather Base) A nonwoven fabric having a weight of 280 g / m ² and a thickness of 1.0 mm was impregnated with a 13% polyurethane-dimethylformamide solution, and an 18% polyurethane-dimethyl After coating the formamide solution with a basis weight of 600 g / m ² , it was immersed and coagulated, washed with water and dried to prepare an artificial leather base.

(Preparation and application of paint liquid mixture-1) Polyamino acid urethane (use of non-yellowing type urethane:
In 100 parts of N, N-dimethylformamide solution (solid content 10%) of LUCKSKIN-UA-3295A (polyamino acid segment 35%, manufactured by Seiko Chemical Co., Ltd.), synthetic polyamino acid particles (manufactured by Ajinomoto Co .; PA-1000; poly-γ-methyl-L-glutamate; average particle size: 10 μm) was added, mixed and dispersed to prepare a stable dispersion. To this, 3 parts of a red pigment (manufactured by Dainippon Ink and Chemicals, Incorporated; DIRAC SL-3440) was added as a colorant and uniformly mixed to obtain a red paint formulation. This coating composition was applied and dried three times with a gravure coater (using a 110 mesh roll) on the surface of the artificial leather base created earlier, and then patterned with a heated embossing roll. An artificial leather having a coating film was obtained. When the surface of the obtained artificial leather touches the skin, it does not make you feel cold, feels warm, and even sweaty skin has no stickiness and excellent tactile sensation, volleyball, handball, It was excellent for basketball. Table 1 shows the obtained characteristic values.

(Preparation of Coating Composition-2) Coating composition-2 was prepared with the following composition.

 Crisbon NY320 (Dainippon Ink and Chemicals, Inc.) 100 parts Howlack A1004 White (Dainippon Ink and Chemicals) 80 parts Haurak A1008 mat (Dainippon Ink and Chemicals) 30 parts Isopropyl alcohol 50 Part Methyl ethyl ketone 40 parts N, N-dimethylformamide 10 parts (Preparation of coating composition-3) Coating composition-3 was prepared with the following composition.

LUCKSKIN-UA3295A (manufactured by Seiko Chemical Co., Ltd.) (18%) 100 parts Ajicoat PA-1000 (manufactured by Ajinomoto Co.) 10 parts Haulac B1356 mat (manufactured by Dainippon Ink and Chemicals, Inc.) 20 parts N, N- 40 parts of dimethylformamide 40 parts of methyl ethyl ketone (application to artificial leather surface) The coating composition liquid-2 was applied to the surface of the artificial leather base prepared in Example-1 with gravure roll (110 mesh) and dried three times. After that, a pattern is formed with a heated embossing roll, and a coating composition liquid-3 is applied to the surface with a gravure roll (110 mesh) and dried and repeated three times.
An artificial leather having a white surface was obtained. The surface of the obtained artificial leather, when touching the skin, does not feel cold, feels warm, has no sticky feeling even on sweaty skin, and has excellent moisture permeability. And was suitable as a shoe upper material. The obtained characteristic values are also shown in Table 1.

(Preparation and application of coating compound liquid-4) Polyamino acid urethane (use of non-yellowing type urethane:
Mitsubishi Chemical Corporation PAU-300; Polyamino acid segment 3
5%) N, N-dimethylformamide solution (solid content 15%)
100 parts of synthetic polyamino acid particles (Ajinomoto Co., Inc.)
(Agikote PA-1000; poly-γ-methyl-L-glutamate; average particle size: 10 μm) was added and mixed and dispersed to prepare a stable dispersion. Among them, black pigment (manufactured by Dainippon Ink and Chemicals, Inc .; DIRAC SL-343) as a colorant
0) 8 parts, black dye (Nippon Kayaku Co., Ltd. Kayaset BLACK
-KR) was added and mixed uniformly to obtain a black paint. This black paint was applied on a patterned release paper so as to have a basis weight of 80 g / m ² and dried, and then an adhesive was applied.
The surface of the artificial leather base prepared in 1 was adhered and sufficiently adhered. The surface of the artificial leather separated from the release paper, when touching the skin, does not feel cold, it feels warm, and even sweaty skin has no sticky feeling and has excellent tactile sensation, tennis It was suitable for racket grip materials and glove flats. The obtained characteristic values are also shown in Table 1.

Comparative Example 1 (Preparation of a coating composition liquid-5) A coating composition liquid-5 was prepared with the following composition.

Haurac A3454 (20%) (manufactured by Dainippon Ink and Chemicals, Inc.) 100 parts Ajicoat PA-1000 (manufactured by Ajinomoto Co., Ltd.) 10 parts Haurak A1008 mat (manufactured by Dainippon Ink and Chemicals, Inc.) 30 parts Isopropyl alcohol 50 parts Methyl ethyl ketone 50 parts (Coating on artificial leather surface) After repeating the coating-drying of the coating composition liquid-2 on the surface of the artificial leather base prepared in Example 1 with a gravure roll (110 mesh) three times, , A pattern is formed with a heated embossing roll, and a coating composition liquid 5 is further applied to the surface thereof with a gravure roll (110 mesh) and dried three times.
An artificial leather having a white surface was obtained. The resulting artificial leather was unsatisfactory in transparency, and when subjected to a bending test, powder likely to be Adiquat PA-1000 was dropped. The obtained characteristic values are also shown in Table 1.

Comparative Example-2 (Preparation of coating composition -6) A coating composition -6 was prepared with the following composition.

LUCKSKIN-UA3295A (manufactured by Seiko Kasei Co., Ltd.) (18%) 100 parts Haurak B1356 mat (manufactured by Dainippon Ink and Chemicals, Inc.) 20 parts N, N-dimethylformamide 40 parts methyl ethyl ketone 40 parts (for artificial leather surface) Coating) After coating-drying the coating composition liquid-2 with a gravure roll (110 mesh) on the surface of the artificial leather base prepared in Example-1 three times, a pattern is formed with a heated embossing roll. The coating liquid-6 was coated on the surface with a gravure roll (110 mesh) and dried and dried three times.
An artificial leather having a white surface was obtained. The obtained artificial leather was unsatisfactory in transparency and had a slightly sticky surface feel. The obtained characteristic values are also shown in Table 1.

Comparative Example-3 (Preparation of coating composition liquid-7) A coating composition liquid-7 was prepared with the following composition.

Howlack A3454 (20%) (Dai Nippon Ink and Chemicals Co., Ltd.) 100 parts Howlack A1008 Matt (Dai Nippon Ink and Chemicals Co., Ltd.) 30 parts Isopropyl alcohol 50 parts Methyl ethyl ketone 50 parts (Coating on artificial leather surface) The coating composition liquid-2 was applied and dried three times on the surface of the artificial leather base prepared in Example 1 with a gravure roll (110 mesh), and then the pattern was formed with a heated embossing roll. The coating composition liquid-7 is applied to the gravure roll (110 mesh) and dried three times.
An artificial leather having a white surface was obtained. The obtained artificial leather is unsatisfactory in transparency, and the tactile feel of the surface is a sticky feeling peculiar to polyurethane of conventional artificial leather, especially when touching with sweaty skin, it feels sticky. there were. The obtained characteristic values are also shown in Table 1.

Claims (3)

(57) [Claims] 1. A coating composition comprising a dispersion of synthetic polyamino acid particles dispersed in an organic solvent solution of a synthetic resin mainly composed of a polyamino acid urethane resin. 2. The polyamino acid urethane is a polyamino acid segment containing poly-γ-methyl-L-glutamate as a main component, and its content is 3% by weight to 85% by weight based on the weight of the polyamino acid urethane resin. Claim (1)
A paint formulation as described. 3. The method according to claim 1, wherein the synthetic polyamino acid particles are poly-γ-methyl-L-glutamate.
A paint formulation as described.