JP3463564B2 - Highly stain resistant polymer coloring material - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a colored plastic or rubber that does not fade or fade, and is resistant to dust and dirt even when exposed to the outdoors, and is semipermanently excellent in antifouling property for a long period of time. The present invention relates to a polymeric coloring material that retains its colorability.

[0002]

2. Description of the Related Art Colored rubbers which have no fading, fading or discoloration are disclosed in JP-A-60-28441 and JP-A-60-350.
No. 41 and the like disclose a technique in which a colorant is chemically bonded to a rubber molecule with a peroxide. By applying this technique, a rubber composition which maintains lubricity for a long period of time is disclosed in JP-A-2-15593.
8. A rubber composition which maintains water repellency is disclosed in JP-A-6-1885.
Is disclosed in.

[0003]

Due to the vividness of the color, the colored rubber produced by the above-mentioned technique colors the swings in the park, playground equipment for slides, structures such as benches and chairs, and the children's body In order to improve safety so as not to be injured even if it hits, it is increasingly used as a material for covering the play equipment and the structure.

However, since it is exposed to the outdoors, it tends to be dusty. In particular, a rubber material is excellent in electrical insulation, and therefore dust and dirt are much more easily attached than when a metal surface is exposed.
Even if a playground equipment or a structure is covered with colored rubber, dust or dirt may cause the fading or dullness of the coloring, resulting in poor appearance.

[0005]

The present invention comprises a coloring agent selected from the group consisting of organic pigments, inorganic pigments and dyes, a vulcanizing agent, and
An antistatic agent having an unsaturated group and a hydrophilic group in a molecule is provided in a coloring material obtained by chemically mixing the coloring agent with a polymer of rubber or plastic by mixing one or more electrophiles. It is characterized by being chemically bonded to the polymer.

The above-mentioned antistatic agent has at least one polymerizable alkenyl group in one molecule, and has sulfonic acid, phosphoric acid, ammonium salt, polyether, polyalcohol, polyamine, and carboxylate. A compound or polymer having a hydrophilic group selected from the group of is preferable.

In the polymeric coloring material of the present invention, the coloring agent, the vulcanizing agent, the electrophile, and the antistatic agent are uniformly kneaded in an unvulcanized state, and then the vulcanizing step of heating and pressing is performed. Another feature is that the antistatic agent near the surface is concentrated while the antistatic agent is transferred from the inside of the molded article toward the surface, and the colorant / antistatic agent is chemically bonded to the polymer.

The rubber component used in the present invention includes natural rubber (NR), styrene-butadiene rubber (SBR), acrylonitrile rubber (NBR), chloroprene rubber (C).
R), polyisoprene rubber (IR), polybutadiene rubber (BR), ethylene propylene rubber (EPR), ethylene propylene three-dimensional polymer rubber (EPDM), chlorosulfonated polyethylene rubber (CMS), ethylene vinyl acetate copolymer rubber Etc. are used as appropriate. In particular, ethylene propylene three-dimensional polymer rubber (EPDM) is preferable in the present invention from the viewpoint of weather resistance and colorability. Further, the plastic of the present invention may be any plastic material that can be further crosslinked intermolecularly or intramolecularly under conditions such as heating. For example, a plastic material obtained by addition-polymerizing a monomer having an unsaturated group such as a polyolefin-based plastic is suitable.

The electrophile of the present invention may be any one as long as it has electrophilicity and does not impair the characteristics of rubber or plastic polymers. Examples of preferable electrophiles include hindered phenols and Grignard reagents. Specifically, pentaerythrityl-tetrakis [3- (3,5-dibutyl-4-hydroxyphenyl) propionate], 2,2-thio-diethylenebis [3- (3,5-dibutyl-4-hydroxy). Phenyl)
Propionate], 2,2-thiobis (4-methyl-6)
-Butylphenol), N, N'-bis [3- (3,5
-Dibutyl-4-hydroxyphenyl) propionyl]
Hindered phenols, such as hydrazine, can be mentioned. Specific examples of the Grignard reagent include isopropyl magnesium chloride and isooctyl magnesium iodide. The amount added is based on 100 parts of the unvulcanized rubber or plastic composition.
It is 0.2 to 20 parts by weight, preferably 0.2 to 10 parts by weight.

As the organic pigment or the organic dye of the colorant used in the present invention, all known ones having a functional group which is easily modified by the electrophile can be used. Especially NH
₂ , NO ₂ , OCH ₃ , CONH ₂ , Cl, CF ₃
Organic pigments and organic dyes having functional groups such as these as substituents on the benzene ring are preferred. Inorganic pigments and dyes can be used in the present invention if they have a metal atom in the molecule. For example, there are zinc white, alumina white, titanium oxide, red iron oxide, litharge, red lead, white lead, yellow lead, zinc yellow, cadmium yellow, molybdenum red and the like. The amount of the pigment or dye added is arbitrarily determined depending on the use of the rubber or plastic of the present invention.

Examples of the vulcanizing agent used in the present invention include sulfur such as white sulfur and colloidal sulfur, sulfur chloride, sulfur compounds such as alkylphenol disulfide and morpholine disulfide, selenium, tellurium, magnesium oxide and lead monoxide. Zinc white and other known vulcanizing agents can be used. Examples of preferred vulcanizing agents of the present invention include organic peroxides, specifically, ketone peroxides,
Examples thereof include peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxydicarbonate and peroxydistel. Specifically, acetylcyclohexyl sulfonyl peroxide, isobutyl peroxide, diisopropyl peroxydicarbonate, acetyl peroxide, succinic acid peroxide, butyl peroxyisobutyrate, butyl peroxylaurylate, butyl peroxyl peroxide, cumene hydro Examples thereof include peroxide and butyl hydroperoxide. The addition amount is 0.5 to 5 parts by weight based on 100 parts by weight of the unvulcanized rubber or plastic composition.

The antistatic agent used in the present invention is a compound having an unsaturated group in the molecule. That is, the unsaturated group can be positively charged by taking an electron by the electrophile, or a radical can be generated by the peroxide to cause a chemical bond with a polymer of rubber or resin. A reagent having at least one group in one molecule and having a hydrophilic group. Preferably, the reagent has a plurality of unsaturated groups and a plurality of hydrophilic groups in one molecule and is compatible with the polymer, and has a property of being compatible or emulsifying with water. It is a hydrophilic compound. In addition, a compound having an electrical characteristic value of 1 × 10 12 or less as an electric characteristic value for expressing chargeability is an antistatic agent. A compound or polymer having a volume resistivity value of 1 × 10 12 to 1 × 10 8 is preferable. The amount of the antistatic agent added is 0.2 to 20 parts by weight based on 100 parts by weight of unvulcanized rubber or plastic. It is preferably 0.5 to 10 parts by weight.

The hydrophilic group in the antistatic agent molecule of the present invention can be selected from the group consisting of sulfonic acid, phosphoric acid, polyether, polyalcohol, polyamine, ammonium salt and carboxylate. Specific examples of the antistatic agent include polymers of polystyrene sulfonic acid, phosphate compounds of β-hydroxyalkyl acrylate such as 2-hydroxyethyl acrylate and phosphoric acid, polyether alcohol represented by polyethylene glycol and acrylic acid. Acrylate compound, copolymer of polyacrylic acid and polyvinyl acetate, ester compound of polyvinyl alcohol and acrylic acid, methacrylate compound containing quaternary ammonium salt in the side chain, iminium salt compound of copolymer of maleimide , And carbobetaine graft copolymers. Further, metal soaps of higher unsaturated carboxylic acids such as oleic acid, linoleic acid, linolenic acid, maleic acid and fumaric acid can also be used.

In the present invention, the above-mentioned coloring agent, vulcanizing agent, electrophile and antistatic agent are kneaded with unvulcanized rubber or plastic by a roll, Banbury mixer or the like. At this time, other known vulcanizing agents, vulcanization aids, processing aids, reinforcing agents, softening agents, extenders, antioxidants or ultraviolet absorbers may be further added to the rubber or plastic. When a rubber or plastic unvulcanized composition is vulcanized by heating and pressurization, the melt viscosity of the unvulcanized composition itself is higher than the melt viscosity of the antistatic agent. The antistatic agent is concentrated in the vicinity of the surface of the molded product, exhibiting a behavior of migrating toward one side. This is considered to be the same phenomenon that a low-viscosity compound behaves so as to cover the interface of a high-viscosity compound in a mixed system of different types of compounds having similar solubility parameters. At the same time as the rubber or plastic polymer is crosslinked intermolecularly or intramolecularly with the vulcanizing agent or electrophile, the colorant and the antistatic agent are also chemically bonded to the polymer and fixed in the polymer.
The vulcanization conditions in the present invention are appropriately selected depending on the mixing system of the unvulcanized composition and additives, and the shape and size of molding. For example,
In the case of rubber, general vulcanization at 150 ° C. or higher at 1 MPa (100 kgf / cm ² ) for 10 minutes is also sufficient.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Table 1 shows the compounding compositions of Examples and Comparative Examples of the present invention. In the composition shown in the table, among the electrophiles, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propinate] was used as the electrophile 1, and N, N '-Bis [3- (3
5-Di-t-butyl-4-hydroxyphenyl) propionyl] hydrazine was used as electrophile 2. Among the antistatic agents, polyalcohol type antistatic agent, trade name: Eletat S (manufactured by Yatasha Yushi Kogyo Co., Ltd.) is used as antistatic agent 1, and ammonium salt type antistatic agent is trade name: Esok PS -909 (Yoshimura Yuka Co., Ltd.) was used as the antistatic agent 2.

In order to numerically evaluate the antifouling effect of Examples 1 to 3 and Comparative Examples 1 and 2, the volume resistivity of each composition was exposed to harsh conditions and evaluated by its change. The results are shown in Table 2. Here, the condition of the weather meter is when exposed to a weather meter device of a xenon lamp for 1000 hours, the condition of heat deterioration is exposed at 120 ° C. for 500 hours, and the condition of water immersion is 500 at 70 ° C. hot water. It refers to the case of immersion for a period of time.

[0017]

[Table 1]

[0018]

[Table 2]

[0019]

INDUSTRIAL APPLICABILITY In the present invention, it is considered that the electrophile takes an electron from the unsaturated group of the antistatic agent to generate a radical or is positively charged, which chemically bonds with the polymer of rubber or resin. . Therefore, it differs from the conventional rubber in which only the antistatic agent is kneaded and mixed in the following points.

Conventional rubber mixed with conductive powder such as metal powder or carbon powder cannot be colored in various colors due to deterioration of physical properties such as rubber elasticity, but the polymer coloring material of the present invention is vivid. It can be colored in various colors and does not deteriorate the physical properties of rubber or plastic.

Further, in a conventional polymer coloring material in which a rubber or plastic is mixed with a surfactant such as sulfonic acid ester, polyethylene glycol, glycerin fatty acid ester or polyalkylamine, when it is immersed in water or exposed to rainwater. These antistatic agents gradually flow out from the coloring material, their charging effect declines, their initial flexibility is lost, and they become hard. However, in the coloring material of the present invention, it is possible to maintain the charging effect even when immersed in water for a long time and prevent the adhesion of dust or dust,
Maintain the original physical properties of rubber or plastic for a long time.

Further, in the present invention, the antistatic agent uniformly dispersed in the unvulcanized rubber or plastic in the kneading step moves to the vicinity of the surface of the molded article in the vulcanizing step of heating and pressing, and the molded body is molded into a mold. Antistatic property is imparted to the surface of the molded product only by taking it out from the mold, and it is not necessary to apply a special antistatic paint or the like to the surface, which is conventionally performed.

Claims (3)

(57) [Claims] 1. A colorant selected from the group of organic pigments, inorganic pigments, and dyes, a vulcanizing agent, and one or more electrophiles are mixed to make the colorant a rubber or plastic polymer. A polymeric coloring material having excellent antifouling properties, which is a chemically bonded coloring material in which an antistatic agent having an unsaturated group and a hydrophilic group in the molecule is chemically bonded to the polymer. 2. The antistatic agent has at least one unsaturated group in one molecule, and sulfonic acid,
Phosphoric acid, polyether, polyalcohol, polyamine,
The polymeric coloring material according to claim 1, which has a hydrophilic group selected from the group of ammonium salts and carboxylates. 3. The colorant, the vulcanizing agent, the electrophile, and the antistatic agent are uniformly kneaded with unvulcanized rubber or plastic, and then the electrification is performed in a vulcanization step of heating and pressing. Polymer coloring characterized by concentrating the antistatic agent near the surface while migrating the inhibitor from the inside of the molded product to the surface and chemically bonding the rubber or plastic polymer with the colorant and antistatic agent material.