JP2007153999A - Coating material composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating material composition which excels in the adhesion to a base material and the flexibility and the uniformity of a coated film in coating on the surface of the elastomer or rubber-containing flexible base material. <P>SOLUTION: The coating material composition comprises (a) 100 pts.wt. hydrogenated product of a copolymer of an aromatic vinyl compound and a conjugated diene compound having a content of the aromatic vinyl compound of less than 45 wt.% and (b) 10-60 pts.wt. hydrogenated product of a copolymer of an aromatic vinyl compound and a conjugated diene compound having a content of the aromatic vinyl compound of 45-80 wt.%. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a coating composition, and more particularly to a coating composition suitable for application to the surface of a soft substrate containing an elastomer or rubber.

In recent years, due to environmental problems, conversion from polyvinyl chloride compounds to thermoplastic elastomers has progressed. Elastomeric products can damp forces including bending and bending, distortion and recovery, and / or repeated torque or vibration during the useful life, and are used in a variety of applications. Further, among soft polyvinyl chloride compounds having a softer Asker C hardness of about 5 to 15, extremely soft thermoplastic elastomers having the same hardness have been developed.

The extremely soft thermoplastic elastomer described above is used as a base material in applications such as simulated bait and toys. In these applications, it is often required to have high design properties, and for this reason, the surface of the base material is painted. There is a need to. Such an extremely soft soft base material is susceptible to external forces such as expansion, contraction, bending, bending, and warping, so that the paint applied on the soft base material can be applied uniformly and such an external It is necessary that the obtained coating film is excellent in flexibility and adhesion to the base material so that it can follow a specific force.

By the way, in a thermoplastic elastomer having a Shore A hardness of about 0 to 85, which is generally used for automobile interior materials, etc., as a coating applied to a substrate made of the thermoplastic elastomer, a coating material has been conventionally used. Excellent strength and / or flexibility and weather resistance of the film, and easy addition of modifiers such as adhesion-imparting agent and / or silane coupling agent. Styrenic resin, acrylic resin, urethane type Resins, epoxy resins and the like are used. However, these paints are suitable for application to substrates having a Shore A hardness of about 0-85, but in application to soft substrates having an Asker C hardness of about 5-15 and high elongation. Is not sufficient in terms of adhesion to the base material and flexibility of the coating film. As a result, as shown in FIG. 1, the soft base material to which the paint is applied is not stretched or bent. When a specific force is applied, the coating film is cracked or peeled off.

Also, styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene / butylene-styrene block copolymer (SEBS), styrene-ethylene / propylene-styrene. Thermoplastic resins such as block copolymers (SEPS); petroleum resins, rosin resins and / or terpene resins as tackifying resins; and methacryloxy, acryloxy, mercapto and / or amino silane cups Heat-proof and moisture-proof insulating coatings containing a ring agent are disclosed (for example, Patent Documents 1 and 2). These paints are applied to electronic parts that have been subjected to insulation treatment, and have excellent adhesion to glass and printed circuit boards. However, when applied to a soft substrate, a uniform coating film cannot be obtained and the coating film formability is poor.

Also, a coating composition comprising a block copolymer comprising a polystyrene unterminated block and a polystyrene butylene rubber intermediate block and a hydrogenated rosin ester as a tackifier, a hydrogenated petroleum resin or a terpene resin modified with an aromatic hydrocarbon Is disclosed (for example, Patent Document 3). This coating composition has excellent chipping resistance, and is used in automobile under bodies, tire houses, and the like. This is excellent for application to a metal substrate such as a steel plate (JIS G 3141), but when applied to a soft substrate, a uniform coating film cannot be obtained and the coating film formability is poor.
JP 2005-162986 A JP 2005-126456 A JP-A-5-179195

The objective of this invention is providing the coating composition which is excellent in the adhesiveness with a base material at the time of applying to a soft base material, and the softness | flexibility of a coating film, and excellent in coating-film formation property.

The present inventor uses two types of hydrogenated products of copolymers of an aromatic vinyl compound and a conjugated diene compound having different aromatic vinyl compound content ratios as a coating film component, thereby providing a coating material having excellent characteristics described above. It was found that a composition was obtained.
That is, the present invention
(A) 100 parts by weight of a hydrogenated copolymer of an aromatic vinyl compound and a conjugated diene compound having an aromatic vinyl compound content of less than 45% by weight, and (b) an aromatic vinyl compound content of 45 to 45% The coating composition contains 10 to 60 parts by weight of a hydrogenated product of 80% by weight of a copolymer of an aromatic vinyl compound and a conjugated diene compound as a coating film component.
The coating composition of the present invention further contains (c) 400 to 1500 parts by weight of an organic solvent.

According to a preferred embodiment of the present invention, the coating composition of the present invention comprises:
(D) It further contains 0 to 40 parts by weight of at least one selected from the group consisting of terpene resin hydrogenated derivatives, petroleum resins, and petroleum resin hydrogenated derivatives.
According to another embodiment of the present invention, each of the copolymer of component (a) and component (b) is a block copolymer or a random copolymer.
According to still another embodiment of the present invention, the component (c) is at least selected from the group consisting of an aromatic organic solvent, an aliphatic solvent, an ester solvent, an alcohol solvent, a paraffin solvent, and a petroleum solvent. One type.

The present invention also provides an article having a coating film containing components (a) and (b) on the surface of a substrate containing an elastomer or rubber having an elongation percentage (according to JIS K 6251 tensile test) of 200% or more. provide.

The coating composition according to the present invention is excellent in adhesion to a base material and flexibility of a coating film when applied to a soft base material, and can be applied uniformly.

Hereinafter, each component of the coating composition according to the present invention will be described.

Component (a): Hydrogenated product of copolymer of aromatic vinyl compound and conjugated diene compound having an aromatic vinyl compound content of less than 45% by weight. Component (a) is a soft film. It is used to adjust the property (followability to deformation of a soft base material). Examples of the aromatic vinyl compound constituting the component (a) include styrene, α-methylstyrene, vinyltoluene, and p-tert-butylstyrene, and one or more types can be used. Of these, styrene is preferable. Examples of the conjugated diene compound include butadiene, isoprene, 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, and pentadiene, and one or more can be used. Of these, butadiene, isoprene, and combinations thereof are preferable.

The content of the aromatic vinyl compound in the component (a) is less than 45% by weight, preferably 5% by weight or more and less than 45% by weight, more preferably 5 to 40% by weight, still more preferably 10 to 40% by weight. It is. When the above upper limit is exceeded, the feel of the coating becomes hard and the flexibility is lost. Moreover, a uniform coating film is not obtained as it is less than the said minimum, and while being inferior to coating-film formation property, it is also inferior to abrasion resistance.

Component (a) is a hydrogenated product of a random copolymer of an aromatic vinyl compound and a conjugated diene compound (hereinafter referred to as a hydrogenated random copolymer), and is a block of an aromatic vinyl compound and a conjugated diene compound. It may be a hydrogenated copolymer (hereinafter referred to as a hydrogenated block copolymer). Particularly preferred is a hydrogenated block copolymer.

In the case of a hydrogenated random copolymer, the number average molecular weight is preferably 5,000 to 1,000,000 and the polydispersity (Mw / Mn) is 10 or less. In addition, the conjugated diene compound portion has a bond form having a double bond in the side chain (for example, 1,2-bond when the conjugated diene compound is butadiene, 1,2-bond when it is isoprene, and 3,4-bond) is preferably 10% or more, more preferably 20 to 90%, and particularly preferably 40 to 90%.

The hydrogenated product of the random copolymer can be produced by hydrogenating the random copolymer by an ordinary method. The random copolymer can be produced, for example, according to the methods described in JP-A-2-158863, JP-A-2-305814 and JP-A-3-72512. Preference is given to those in which at least 90% of the aliphatic double bonds based on conjugated diene compounds are hydrogenated.

The hydrogenated block copolymer is a hydrogenated block copolymer comprising at least one polymer block A mainly composed of an aromatic vinyl compound and at least one polymer block B mainly composed of a conjugated diene compound. It is obtained by adding. For example, it can be obtained by hydrogenating a block copolymer having a structure such as A-B, A-B-A, B-A-B-A, or A-B-A-B-A.

The polymer block A mainly composed of an aromatic vinyl compound may be a polymer composed only of an aromatic vinyl compound or a copolymer of an aromatic vinyl compound and less than 50% by weight of a conjugated diene compound. The polymer block B mainly composed of a conjugated diene compound may be a polymer composed solely of a conjugated diene compound or a copolymer of a conjugated diene compound and less than 50% by weight of an aromatic vinyl compound.

The polymer block A mainly composed of an aromatic vinyl compound is preferably present in a proportion of less than 45% by weight of the entire hydrogenated block copolymer.

The polymer block B mainly composed of the conjugated diene compound is hydrogenated at an arbitrary ratio, but the hydrogenation rate is preferably 50% or more, more preferably 55% or more, and further preferably 60% or more. Moreover, the coupling | bonding form of a conjugated diene compound is arbitrary, for example, when the block B is comprised only with a butadiene, in a polybutadiene block, 1, 2- bond becomes like this. Preferably it is 20 to 50%, Most preferably, it is 25 to 45. %. Further, 1,2-bonded ones may be selectively hydrogenated. When block B is composed of a mixture of isoprene and butadiene, the 1,2-bond is preferably less than 50%, more preferably less than 25%, and even more preferably less than 15%.

When block B is composed of isoprene alone, in the polyisoprene block, 1,4-bonds are preferably 70-100% and preferably at least 90% of the aliphatic double bonds derived from isoprene are hydrogenated The ones made are preferred.

The hydrogenated block copolymer preferably has a weight average molecular weight of 500,000 or less, more preferably from 50,000 to 350,000. If the weight average molecular weight exceeds 500,000, the film-forming property may be lowered. When the weight average molecular weight is less than 50,000, the strength of the coating film is insufficient.

Specific examples of the hydrogenated block copolymer include styrene-ethylene-butadiene copolymer (SEB), styrene-ethylene-propylene copolymer (SEP), styrene-ethylene-butadiene-styrene copolymer (SEBS), Styrene-ethylene-propylene-styrene copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS), styrene-butadiene-butylene-styrene copolymer (partially hydrogenated styrene-butadiene-styrene copolymer) Polymer, SBBS) and the like.

Many methods have been proposed as a method for producing a hydrogenated block copolymer. As a typical method, for example, block polymerization is carried out in an inert medium using a lithium catalyst or a Ziegler type catalyst by the method described in Japanese Patent Publication No. 40-23798, and the block copolymer thus obtained is obtained. A method of performing a hydrogenation treatment in the presence of a hydrogenation catalyst in an inert solvent by a known method can be mentioned.

Component (b) Hydrogenated product of copolymer of aromatic vinyl compound and conjugated diene compound having a styrene content of 45 to 80% by weight Component (b) adjusts the hardness of the coating film. And used to enable the formation of a uniform coating. Examples of the aromatic vinyl compound and the conjugated diene compound constituting the component (b) include the same compounds as those described for the component (a).

The content of the aromatic vinyl compound in the component (b) is 45 to 80% by weight, preferably 45 to 75% by weight, more preferably 45 to 70% by weight. When the above upper limit is exceeded, the flexibility of the coating film and the adhesion to the soft substrate are insufficient. If it is less than the above lower limit, the hardness and uniformity of the coating film are insufficient.

Component (b) is a block of an aromatic vinyl compound and a conjugated diene compound even if it is a hydrogenated random copolymer of an aromatic vinyl compound and a conjugated diene compound (hereinafter referred to as a hydrogenated random copolymer). It may be a hydrogenated copolymer (hereinafter referred to as a hydrogenated block copolymer). Particularly preferred is a hydrogenated block copolymer.

In the case of a hydrogenated random copolymer, the number average molecular weight is preferably 5,000 to 1,000,000 and the polydispersity (Mw / Mn) is 10 or less. In addition, the conjugated diene compound portion has a bond structure having a double bond in the side chain (for example, a 1,2-bond structure when the conjugated diene compound is butadiene, and a 1,2-bond when it is isoprene. Structure and 3,4-bond structure) is preferably 10% or more, more preferably 20 to 90%, particularly preferably 40 to 90%.

The hydrogenated product of the random copolymer can be produced by hydrogenating the random copolymer by an ordinary method. The random copolymer can be produced, for example, according to the methods described in JP-A-2-158863, JP-A-2-305814 and JP-A-3-72512. Preference is given to those in which at least 90% of the aliphatic double bonds based on conjugated diene compounds are hydrogenated.

The hydrogenated block copolymer is a hydrogenated block copolymer comprising at least one polymer block A mainly composed of an aromatic vinyl compound and at least one polymer block B mainly composed of a conjugated diene compound. It is obtained by adding. For example, it can be obtained by hydrogenating a block copolymer having a structure such as A-B, A-B-A, B-A-B-A, or A-B-A-B-A.

The polymer block A mainly composed of an aromatic vinyl compound may be a polymer composed only of an aromatic vinyl compound or a copolymer of an aromatic vinyl compound and less than 50% by weight of a conjugated diene compound. The polymer block B mainly composed of a conjugated diene compound may be a polymer composed solely of a conjugated diene compound or a copolymer of a conjugated diene compound and less than 50% by weight of an aromatic vinyl compound.

The polymer block A mainly composed of an aromatic vinyl compound is preferably present in a proportion of 45 to 80% by weight of the whole hydrogenated block copolymer.

The polymer block B mainly composed of the conjugated diene compound is hydrogenated at an arbitrary ratio, but the hydrogenation rate is preferably 50% or more, more preferably 55% or more, and further preferably 60% or more. Moreover, the coupling | bonding form of a conjugated diene compound is arbitrary, for example, when the block B is comprised only with a butadiene, in a polybutadiene block, a 1, 2- bond is preferably 20 to 50%, Most preferably, it is 25 to 45. %. Further, 1,2-bonded ones may be selectively hydrogenated. When block B is composed of a mixture of isoprene and butadiene, the 1,2-bond is preferably less than 50%, more preferably less than 25%, and even more preferably less than 15%.

When block B is composed of isoprene alone, in the polyisoprene block, 1,4-bonds are preferably 70-100% and preferably at least 90% of the aliphatic double bonds derived from isoprene are hydrogenated The ones made are preferred.

The hydrogenated block copolymer preferably has a weight average molecular weight of 500,000 or less, more preferably from 50,000 to 350,000. If the weight average molecular weight exceeds 500,000, the film-forming property may be lowered. When the weight average molecular weight is less than 50,000, the strength of the coating film is insufficient.

Specific examples of the hydrogenated block copolymer include styrene-ethylene-butadiene copolymer (SEB), styrene-ethylene-propylene copolymer (SEP), styrene-ethylene-butadiene-styrene copolymer (SEBS), Styrene-ethylene-propylene-styrene copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene copolymer (SEEPS), styrene-butadiene-butylene-styrene copolymer (partially hydrogenated styrene-butadiene-styrene copolymer) Polymer, SBBS) and the like.

Many methods have been proposed as a method for producing a hydrogenated block copolymer. As a typical method, for example, block polymerization is carried out in an inert medium using a lithium catalyst or a Ziegler type catalyst by the method described in Japanese Patent Publication No. 40-23798, and the block copolymer thus obtained is obtained. A method of performing a hydrogenation treatment in the presence of a hydrogenation catalyst in an inert solvent by a known method can be mentioned.

The coating composition of this invention contains the said component (a) and (b) as a coating-film component. The blending ratio of these components is 10 to 60 parts by weight, preferably 10 to 55 parts by weight of component (b) with respect to 100 parts by weight of component (a). When the compounding ratio of the component (b) with respect to 100 parts by weight of the component (a) exceeds the above upper limit, the flexibility of the coating film and the adhesion with the soft substrate are insufficient. If it is less than the above lower limit, the hardness and uniformity of the coating film are insufficient.

Component (c): Organic solvent The coating composition of the present invention comprises component (c) an organic solvent together with the coating film components (a) and (b). Examples of the organic component include aromatic solvents such as toluene and xylene, aliphatic solvents such as cyclohexane, methylcyclohexane, and ethylcyclohexane, ester solvents such as ethyl acetate, butyl acetate, and isopropyl acetate, ethanol, butanol, and the like. Examples include alcohol solvents, paraffin solvents such as paraffin oil and naphthenic oil, and petroleum solvents such as miller terpenes and naphtha.

Component (c) preferably has a boiling point of 150 ° C. or lower from the standpoint of room temperature drying time.

The amount of the component (c) is determined according to the viscosity of the coating material related to workability, but is 400 to 1600 parts by weight, preferably 500 to 1400 parts by weight with respect to 100 parts by weight of the component (a). If it is less than the lower limit, the viscosity of the paint is too high, and the coating operation becomes difficult. If the upper limit is exceeded, the paint is easily sagged, it becomes difficult to form a coating film, and the drying time becomes longer.

Component (d): terpene resin hydrogenated derivative, petroleum resin and / or petroleum resin hydrogenated derivative Component (d) is a component that is optionally added as an adhesion-imparting agent, and adheres to the coating on the substrate. The function to improve the property is added.

Component (d-1): Terpene resin hydrogenated derivative As the component (d-1), any terpene resin hydrogenated derivative can be used. Examples include hydrogenated derivatives of terpene resins such as terpene resins obtained by polymerizing α-pinene and β-pinene, terpene phenol resins obtained by reacting phenol and terpene, and aromatic modified terpene resins imparted with styrene or the like. Can do.

Hydrogenated derivatives of terpene resins can be obtained by hydrogenating terpene resins by methods known to those skilled in the art.

A commercial item can also be used as a component (d-1), for example, the clearon (hydrogenated terpene resin) by Yashara Chemical Co., Ltd. is mentioned.

Component (d-2): Petroleum resin and petroleum resin hydrogenated derivative Petroleum resin is a resinous substance obtained in various processes in the petroleum refining industry and petrochemical industry, or those processes, particularly a decomposition process of naphtha. It refers to a resin obtained by copolymerization using an unsaturated hydrocarbon obtained in (1) as a raw material. For example, aromatic petroleum resins mainly composed of C5 fraction, copolymerized petroleum resins thereof, and alicyclic petroleum resins can be exemplified. Preferred petroleum resins are aliphatic petroleum resins, aromatic petroleum resins, copolymer petroleum resins, and alicyclic petroleum resins.

Component (d-2) also includes hydrogenated derivatives of the above petroleum resins. The petroleum resin hydrogenated derivative is preferably completely hydrogenated. Those that are partially hydrogenated tend to be inferior in terms of thermal stability and weather resistance.

A hydrogenated derivative of a petroleum resin can be obtained by hydrogenating the above petroleum resin produced by a conventional method by a conventional method.

In particular, petroleum resin hydrogenated derivatives are preferred for molded articles that require heat resistance. More preferably, a hydrogenated derivative of an aliphatic petroleum resin is used, and among these, a hydrogenated derivative obtained by copolymerizing a cyclopentadiene compound is particularly preferable.

When blended, the amount of component (d) is 40 parts by weight or less, preferably 10 to 30 parts by weight per 100 parts by weight of component (a). When the upper limit is exceeded, the tackiness is remarkably increased and the coating film formability is deteriorated.

The coating composition of the present invention can optionally contain, in addition to the components (a) to (d), a wetting and dispersing agent, a leveling agent, a colorant, and the like.

Examples of the wetting and dispersing agent include known wetting and dispersing agents such as anionic, cationic, and urethane-modified acrylic copolymers.

Examples of the leveling agent include known leveling agents such as silicon glycol, modified polysiloxane, and amino resin-modified acrylic copolymer.

Examples of the colorant include known inorganic pigments, organic pigments, and organic dyes, and are used according to a desired color tone. These colorants may be used in combination of two or more.

The coating composition of this invention is obtained by melt-mixing the said component at normal temperature using a general stirring and defoaming apparatus. Examples of the stirrer include, for example, a rotor-stator type stirrer such as a resolver and a homogenizer, a planetary stirrer that revolves and mixes a container at the same time as rotating, a sand mill, a bead mill, a ball mill, a colloidal mill, a paint Examples thereof include those that are dispersed while applying mechanical shearing force by a shaker, a static mixer, a jet mixer, a bubble homogenizer, an ultrasonic homogenizer, or the like.

The coating composition thus obtained is excellent in adhesion to the substrate, flexibility and uniformity of the coating film when applied to the surface of a soft substrate containing an elastomer or rubber. In particular, it is useful for application to the surface of a substrate containing an elastomer or rubber having an elongation percentage (using No. 3 dumbbell according to JIS K 6251 tensile test, tensile speed 500 mm / min) of 200% or more. FIG. 2 is a photograph showing a state when a coating composition of the present invention applied to the surface of a soft substrate is stretched. As can be seen from FIG. 2, when applied to a soft substrate, the coating composition of the present invention does not crack or peel off the coating film even when an external force such as elongation or bending is applied. Since the conventional paint shown in FIG. 1 is white and the paint of the present invention shown in FIG. 2 is red, both have a difference in brightness.

As a coating method, various generally known methods can be used, and examples thereof include spray coating, roll coating, and brush coating.

Examples of the base material containing an elastomer or rubber having an elongation of 200% or more include, for example, styrene rubber or elastomer (SBR, SBS, SIS, hydrogenated SBR, SEPS, SEBS, SEEPS, etc.) and / or olefin rubber. (EPR, EBR, EPDM, etc.) etc. can be exemplified by oils blended and softened within a range that does not impair the purpose. The formulation examples are shown in Table 1 below.

EXAMPLES Next, although this invention is demonstrated in detail using an Example and a comparative example, this invention is not limited to a following example. The evaluation methods and raw materials used in Examples and Comparative Examples are as follows.

Evaluation method (1) Production of substrate:
A substrate for applying the coating composition was prepared according to the composition shown in Table 1. Each component shown in Table 1 was put into a twin screw extruder having an L / D of 47, and melt kneaded at a kneading temperature of 180 ° C. and a screw rotation speed of 350 rpm to be pelletized. The obtained pellet was subjected to residual heat 2 minutes / pressurization 2 minutes (pressure 50 kg / cm ² ) to produce a hot press sheet having a length of 90.0 mm, a width of 50.0 mm, and a thickness of 3.0 mm. A soft substrate having the physical properties shown in 1 was obtained.

(2) Adhesion test with substrate:
The coating material was spray-applied to the base material obtained in (1) so as to have a film thickness of about 200 μm, and dried at room temperature for 1 day to prepare a test piece. Using this test piece, according to JIS K 5400, 11 parallel lines that are perpendicular to the center of the test piece are drawn at 1 mm intervals to cut a grid-like cut so that 100 squares can be formed. Attach with. The presence or absence of grids remaining without missing the grids was visually observed and evaluated according to the following criteria.
○: The proportion of cells remaining without loss is 90% or more.
(Triangle | delta): The ratio of the cell which remains without being missing is 70% or more and less than 90%.
X: The proportion of cells remaining without loss is less than 70%.

(3) Coating film flexibility test:
The coating material was spray-applied to the base material obtained in (1) so as to have a film thickness of about 200 μm, and dried at room temperature for 1 day to prepare a test piece. Both ends of this test piece are fixed, and the test piece is fixed in a state where the length of the test piece is extended to double length (180.0 mm). After standing at room temperature (23 ° C.) for 1 hour, the coating film was visually observed for cracks, cracks and peeling, and evaluated according to the following criteria.
○: No cracks, cracks or peeling.
Δ: There are some cracks, cracks and peeling.
X: Any of cracks, cracks and peeling is remarkable.

(4) Coating film formation test A coating material is sprayed and applied to the base material obtained in the above (1) by an air gun so as to have a film thickness of about 200 μm. After drying at room temperature (23 ° C.) for 3 hours, the uniformity of the spray particles and the uniformity of the coating film were visually observed and evaluated according to the following criteria.
○: The spray particles are uniform and the coating film is uniform.
(Triangle | delta): A spray particle is somewhat nonuniform and / or a coating film is somewhat nonuniform.
X: The spray particle is remarkably nonuniform and / or the coating film is remarkably nonuniform.

Raw materials for coating compositions
Component (a):
Component (a-1): H1651 (trademark; manufactured by Clayton Japan), linear SEBS (styrene-ethylene-butene-styrene block copolymer), specific gravity 0.92, aromatic vinyl compound content 33% by weight, weight average Molecular weight 130,000 components (a-2): Septon 4033 (trademark; manufactured by Kuraray Co., Ltd.), SEEPS (styrene-ethylene / ethylene / propylene / styrene block copolymer), specific gravity 0.91, aromatic vinyl compound content 30% by weight, weight average molecular weight 130,000 components (a-3): Dynalon 1320P (trademark; manufactured by JSR), hydrogenated SBR (hydrogenated styrene / butadiene random copolymer), number average molecular weight 300,000, Mw / Mw = 1.1, aromatic vinyl compound content 10%
Component (a-4) (for comparison): Dynalon 6200P (manufactured by JSR), CEBC (block polymer having a crystalline ethylene block and an amorphous ethylene-butene block), styrene content 0%

Component (b):
Component (b-1): Septon 2104 (trademark; manufactured by Kuraray Co., Ltd.), SEPS (styrene-ethylene-propylene-styrene block copolymer), specific gravity 0.98, aromatic vinyl compound content 65% by weight, weight Average molecular weight 90,000 components (b-2): Septon 1050 (trademark; manufactured by Kuraray Co., Ltd.), SEP (styrene-ethylene / propylene block copolymer), specific gravity 0.94, aromatic vinyl compound content 50% by weight , Weight average molecular weight 150,000 components (b-3) (for comparison): Septon 2007 (trademark; manufactured by Kuraray Co., Ltd.), SEPS (styrene-ethylene-propylene-styrene block copolymer), specific gravity 0.92 aromatic Vinyl compound content 30% by weight, weight average molecular weight 90,000 components (b-4) (for comparison): G200 (trademark; manufactured by Toyo Styrene Co., Ltd.) , PS (polystyrene), MFR 8.5 (230 ° C. × 2.16 kg) 10 dg / min, specific gravity 1.05, flexural modulus 3330 MPa

Component (c):
Component (c-1): Xylol (dimethylbenzene), manufactured by Gordo Solvent Co., Ltd., density (20 ° C.) 0.8802, melting point−25.23 ° C., boiling point 144.4 ° C.
Component (c-2): Hexahydrobenzene (cyclohexane), manufactured by Wako Pure Chemical Industries, Ltd., specific gravity (20 ° C.) 0.78, average molecular weight 84.16, boiling point (° C.) 80.74

Component (d):
Component (d-1) Hydrogenated derivative of terpene resin: Clearon P-125 (trademark; manufactured by Yasuhara Chemical Co., Ltd.), softening temperature 125 ° C., glass transition temperature 68 ° C.
Component (d-2) Petroleum resin hydrogenated derivative: Imabe P-140 (trademark; manufactured by Idemitsu Petrochemical Co., Ltd.), softening temperature 140 ° C., average molecular weight 910, density 1.03

Examples 1-10 and Comparative Examples 1-6
The coating compositions of Examples 1 to 10 and Comparative Examples 1 to 6 were produced by dissolving and mixing the components shown in Tables 2 and 3 at room temperature (23 ° C.) using a planetary stirring and defoaming apparatus. Moreover, the evaluation test of said (2)-(4) was done using the obtained coating composition. The results are shown in Tables 2 and 3.

As is apparent from Table 2, the coating composition according to the present invention has excellent adhesion, flexibility and uniformity (coating film formability) of the coating film when applied to a soft substrate.

On the other hand, as is clear from Table 3, two types of component (a) were used without using component (b) (that is, the aromatic vinyl compound content of component (b) was less than the lower limit of the present invention. ) The composition of Comparative Example 1 and the composition of Comparative Example 2 in which the blending amount of the component (b) was less than the lower limit of the present invention were remarkably deteriorated in coating film formation, and a uniform coating film was not obtained. In the composition of Comparative Example 3 in which the amount of component (b) exceeds the upper limit of the present invention, the adhesion and flexibility deteriorated, and the coating film cracked. Two types of component (b) were used without using the composition and component (a) of Comparative Example 4 in which the aromatic vinyl compound content of component (b) exceeded the upper limit of the present invention (that is, component (a) In the composition of Comparative Example 5 in which the aromatic vinyl compound content exceeds the upper limit of the present invention, the adhesion and flexibility deteriorated, and the coating film was cracked. The composition of Comparative Example 6 is an example in which a hydrogenated copolymer having an aromatic vinyl compound content of 0% by weight is used as component (a). In this composition, the fluidity was lowered and the film-forming property was deteriorated, and a uniform coating film could not be obtained.

  The coating composition of the present invention can be satisfactorily applied to the surface of a soft substrate containing an elastomer or rubber, and is useful as a coating on the substrate surface in simulated bait, toys and the like.

It is a photograph which shows a state when what applied the conventional coating material to the surface of the soft base material was extended. It is a photograph which shows a state when what applied the coating material of this invention to the surface of the soft base material was extended.

Claims (6)

(A) 100 parts by weight of a hydrogenated product of a copolymer of an aromatic vinyl compound and a conjugated diene compound having an aromatic vinyl compound content of less than 45% by weight, and (b) an aromatic vinyl compound content of 45 A coating composition comprising 10 to 60 parts by weight of a hydrogenated product of a copolymer of an aromatic vinyl compound and a conjugated diene compound, which is -80% by weight. (C) The coating composition according to claim 1, further comprising 400 to 1500 parts by weight of an organic solvent. The coating composition according to claim 2, further comprising 0 to 40 parts by weight of at least one selected from the group consisting of (d) a terpene resin hydrogenated derivative, a petroleum resin, and a petroleum resin hydrogenated derivative. Each of the copolymer of a component (a) and a component (b) is a block copolymer or a random copolymer, The coating composition of any one of Claims 1-3 characterized by the above-mentioned. The component (c) is at least one selected from the group consisting of an aromatic organic solvent, an aliphatic solvent, an ester solvent, an alcohol solvent, a paraffin solvent, and a petroleum solvent. The coating composition of any one of -4. An article having a coating film containing components (a) and (b) on the surface of a substrate containing an elastomer or rubber having an elongation (according to JIS K 6251 tensile test) of 200% or more.

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