JPWO2006035708A1 - Coating composition for protection of hydraulic transfer pattern layer, decorative molded product and method for producing the same - Google Patents

Abstract

With respect to a transfer molded product obtained by water-transferring a pattern layer formed by printing or painting on a water-soluble or swellable film base material onto a polypropylene resin molded product, the polypropylene resin molded product and A coating composition for protecting a hydraulic transfer pattern layer that produces a protective coating having adhesion to both the pattern layer, the resin component (A) comprising a chlorinated polypropylene resin, cyclohexyl methacrylate, and methacrylic acid t —Hydroxyl-containing resin composition (P) obtained by graft polymerization of polyol component (B) composed of acrylic polyol composed of butyl, styrene, and hydroxyethyl methacrylate is cured with polyisocyanate curing agent (Q). Use a protective coating.

Description

The present invention relates to a polypropylene molded product obtained by transferring a pattern layer formed by printing or painting on a water-soluble or swellable film base material onto a polypropylene resin molded product by hydraulic transfer. The present invention relates to a coating composition that produces a protective coating film having excellent adhesion to both a resin molded article and the patterned layer, a decorative molded article protected by the coating composition, and a method for producing the same.
This application claims the priority based on Japanese Patent Application No. 2004-282562 for which it applied to Japan Patent Office on September 28, 2004, and uses the content here.

Recently, a hydraulic transfer method has been used to decorate various kinds of patterns such as wood grain and lattice patterns on resin molded articles having a complicated surface shape. This method uses a water-insoluble or water-swellable film and a water-insoluble component to float a transfer film on which a predetermined pattern layer (also called a transfer layer) is printed on the water surface in the transfer tank. The pattern layer is transferred onto the surface of the resin molded product by placing the resin molded product on it and submerging it in water.
As resin molded products, resin molded products such as ABS resin, acrylic resin, and polycarbonate resin have been used, but the adhesive strength of the transferred pattern layer to the resin molded product is not sufficient, such as water resistance and alkali resistance. It was insufficient to provide chemical resistance and other durability such as heat resistance, weather resistance, and abrasion resistance. Therefore, a protective coating for the purpose of protection is applied on the pattern layer. This protective coating not only satisfies the above-mentioned various performances, but also gives the pattern layer a sense of transparency and a feeling of fleshiness, giving it a further design.

  However, in recent years, polypropylene resin molded products have been widely used for interior and exterior parts of automobiles in terms of recyclability and cost. Conventional protective coatings have used acrylic or urethane paints that have adhesion to ABS resins, acrylic resins, polycarbonate resins, etc., but they adhere to polypropylene resins that are extremely low in polarity and difficult to adhere. However, there is a problem that the adhesive strength decreases with time or due to heat, light, humidity, or the like.

In JP-A-2001-232998, a transfer film having a printing pattern activated by an activator is floated on a liquid surface, and a transfer object is immersed under the liquid surface relative to the transfer film. In the hydraulic transfer method in which a printing pattern on the transfer film is transferred by hydraulic pressure, and a protective coating film is formed on the transfer object onto which the printing pattern is transferred, the activator that activates the printing pattern is And a binder resin formed by adding a hydrophilic component to the chlorinated polyolefin, and the protective coating film has adhesion to both the transferred object and the printed pattern thereon and the protective coating film. A method of forming on an object to be transferred via an intermediate coating film is disclosed (see Patent Document 1).
However, in this technique, the transfer film is activated by using an activator containing a binder resin, and then transferred, and the unsaturated group-containing vinyl having a Tg of 50 ° C. or higher is transferred onto the transferred material onto which the print pattern is transferred. Intermediate coating film containing, as binder resin, a graft copolymer comprising 5 to 95% by weight of monomer, 50% by weight or less of unsaturated group-containing vinyl monomer having a Tg of less than 50 ° C., and 1 to 50% by weight of chlorinated polypropylene resin Form. A protective coating film containing an acrylic polyol resin having an OH value of 10 to 200 mg-KOH / g and / or a polyester polyol resin having an OH value of 10 to 400 mg-KOH / g is formed thereon. Thus, in the said technique, it is necessary to form a protective coating film through an intermediate coating film.

JP-A-2001-232998 (Claims 1 to 7, Examples)

  The problems to be solved by the present invention include, in addition to solving the above-mentioned problems, a coating composition capable of giving a sense of transparency and a feeling of flesh in order to impart the original design properties, and a coating composition thereof. An object of the present invention is to provide an article using the printed film to protect it.

  As a result of intensive studies, the present inventor has obtained a hydroxyl group-containing resin composition obtained by graft polymerization of a chlorinated polypropylene resin and an acrylic polyol component composed of cyclohexyl methacrylate, t-butyl methacrylate and hydroxyethyl methacrylate. By using a protective coating film cured with a polyisocyanate curing agent, it was found that a protective coating film having excellent adhesion to both the polypropylene resin molded article and the pattern layer was obtained, and the present invention was It came to complete.

That is, according to the first aspect of the present invention, a pattern layer (4) applied by printing or coating on a water-soluble or swellable film substrate (support film) is formed on a polypropylene resin molded article (3). In addition, a protective coating film (5) having adhesion to both the polypropylene resin molded product (3) and the patterned layer (4) is produced with respect to the transfer molded product (2) obtained by hydraulic transfer. A polyol composition comprising a resin component (A) containing at least a modified polyolefin resin (a) and at least one selected from the group consisting of acrylic polyol, polyester polyol, polycarbonate polyol and polyurethane polyol, which is a protective coating composition Hydrostatic transfer pattern layer holding comprising a hydroxyl group-containing resin composition (P) obtained by graft polymerization of (B) and a polyisocyanate curing agent (Q). Providing use coating composition.
According to a second aspect of the present invention, in the protective coating composition according to the first aspect of the present invention, the modified polyolefin resin (a) is chlorinated polypropylene, acrylic-modified chlorinated polypropylene resin, maleic anhydride-modified. Provided are protective coating compositions that are polypropylene, non-chlorinated maleic acid-modified polyolefin resins, and mixtures thereof.
According to a third aspect of the present invention, in the protective coating composition according to the first aspect of the present invention, the resin composition (P) is 1 to 20% by weight of a resin component (A) and a polyol component in terms of solid content. (B) A protective coating composition comprising 99 to 80% by weight (the total of both is 100% by weight) is provided.
According to a fourth aspect of the present invention, there is provided the protective coating composition according to the first protective coating composition of the present invention, wherein the polyol component (B) has a glass transition temperature of 50 ° C or higher.
According to a fifth aspect of the present invention, in the protective coating composition according to the first aspect of the present invention, the polyol component (B) is cyclohexyl (b) (5) to 60% by weight, (meth) acrylic. T-butyl acid (c) 5 to 60% by weight, styrene (f) 5 to 60% by weight, hydroxyalkyl (meth) acrylate (2 to 4 carbon atoms) (d) 3 to 20% by weight and as required Provided is a protective coating composition which is an acrylic polyol composed of 82 to 0% by weight of other polymerizable monomer (e) added (the total of these components is 100% by weight).
According to a sixth aspect of the present invention, there is provided the protective coating composition according to the first aspect of the present invention, wherein the resin composition (P) has a hydroxyl value of 10 to 100 mg-KOH / g. To do.
In the seventh aspect of the present invention, a pattern layer (4) applied by printing or coating on a water-soluble or swellable film base material (support film) is formed on a polypropylene resin molded article (3). According to the first to sixth aspects of the present invention, both the polypropylene resin molded product (3) and the patterned layer (4) have adhesion to the transfer molded product (2) obtained by hydraulic transfer. Provided is a method for producing a decorative molded article (1) in which the protective coating composition described in any one of the above is applied and heat-cured.
In an eighth aspect of the present invention, a pattern layer (4) applied by printing or coating on a water-soluble or swellable film substrate (support film) is formed on a polypropylene resin molded article (3). The transfer molded product (2) obtained by hydraulic transfer, and the first to first of the present invention having adhesion to both the polypropylene resin molded product (3) and the patterned layer (4) on the transfer molded product. A decorative molded article (1) comprising a protective coating film obtained by applying the protective coating composition according to any one of aspects 6 and heat-curing is provided.

According to the present invention, it is possible to secure adhesion with a polypropylene-based resin molded product that is difficult to adhere to a transfer molded product obtained by hydraulic transfer, and furthermore, adhesion with the pattern layer. Protective coating film with excellent coating performance such as water resistance, alkali resistance, oil resistance, weather resistance, impact resistance, hardness, and excellent appearance quality such as sharpness, smoothness, and fleshiness .
Further, since the protective coating composition is grafted with the resin component (A) containing the modified polyolefin resin (a), which is hardly compatible, and the polyol component (B), the compatibility between them is good. Excellent storage stability and low viscosity. As a result, it gives excellent design and brings about high appearance quality.

FIG. 1 is a configuration diagram of a transfer molded product according to an embodiment. FIG. 2 is a configuration diagram of a decorative molded product according to the example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Decorative molded product 2 Transfer molded product 3 Polypropylene resin molded product 4 Pattern layer 5 Protective coating

An embodiment of the present invention will be described with reference to FIGS.
The protective coating composition of the present invention has the polypropylene resin molded product 3 and the pattern layer 4 in contrast to the transfer molded product 2 obtained by hydraulic transfer of the pattern layer 4 onto the polypropylene resin molded product 3. It is a coating composition which produces the protective coating film 5 which has the adhesiveness excellent in both.

(I) Polypropylene resin molded product The polypropylene resin used in the polypropylene resin molded product 3 according to the present invention is not particularly limited as long as it is used in a molded product. For example, polypropylene homopolymer, carbon such as ethylene, etc. Copolymers with other olefins of several 3 to 10, ternary copolymers obtained by copolymerizing other components such as linear or cyclic diene components, or those having a functional group added thereto Also good. These may be single or a mixture. As long as these polypropylene resins can be used in the present invention, there are no limitations on the type of polymerization catalyst and the molecular weight of the polymer.
The molecular structure of the copolymer is not particularly limited, and examples thereof include a block copolymer, a random copolymer, and a block-random copolymer.
Examples of the functional group imparted to the polypropylene resin include a carboxyl group, a hydroxyl group, an amide group, and an amino group, and these are imparted using a monomer that is copolymerized in the polymerization step of the polypropylene resin. Alternatively, it may be applied by post-treatment such as chemical treatment, flame treatment, or active energy ray treatment after forming into a strand, pellet or molded product. Examples of the copolymerization monomer for imparting a functional group include maleic anhydride, maleic acid, fumaric acid, (meth) acrylic acid, hydroxyethyl (meth) acrylate, vinyl acetate, (meth) acrylamide, and aminostyrene. .

(II) Transfer Film The transfer film according to the present invention is on a water-soluble or water-swellable support film having a thickness of about 5 to 300 μm (sometimes referred to as a film base or a pattern layer support). In addition, the predetermined pattern layer 4 is formed by printing, coating or the like so that the predetermined pattern layer 4 is 0.1 to 100 μm, usually 1 to 10 μm, using a water-insoluble component.

(II-1) Pattern layer The material of the pattern layer 4 according to the present invention is hydrophobic and includes the following.
(1) A film composed of a hydrophobic ink or paint film that can be dissolved in an organic solvent, or (2) The above (1) is provided on a base protective layer composed of an active energy ray curable resin or a thermosetting resin. There are things that were made.
The film thickness of the pattern layer 4 is not particularly limited, but is 0.1 to 15 [mu] m, preferably 1 to 10 [mu] m when the pattern layer 4 is composed only of a film layer of ink or paint. When a coating layer of ink or paint is provided on the base protective layer, the thickness is 1 to 200 μm, preferably 10 to 100 μm.
In any of the above cases, if the film thickness is too thin than the above range, the required design properties and undercoat protection are insufficient, and if the film thickness is too thick, it is difficult to uniformly activate the pattern layer during hydraulic transfer. It becomes. The activation of the pattern layer can be achieved by applying or dispersing an organic solvent to the pattern layer so that the decorative layer and, if necessary, the resin constituting the pattern layer further comprising the cured resin layer are not completely dissolved. The pattern layer is formed by solubilizing and facilitating peeling of the hydrophobic pattern layer from the hydrophilic support film (pattern layer support or film substrate) and imparting flexibility to the pattern layer during hydraulic transfer. It has the function of improving the followability to the three-dimensional curved surface and the adhesion of the transferred material.
The above ink or paint must be activated by an organic solvent, but it is important to maintain flexibility to the extent that the pattern does not flow. Gravure printing ink, inkjet printing ink, epoxy / urethane resin-based paint, addition Examples thereof include polymer coatings and condensation polymerization coatings.
The varnish resin used in the ink or paint is acrylic resin, polyurethane resin, polyamide resin, urea resin, epoxy resin, polyester resin, vinyl resin (vinyl chloride, vinyl acetate copolymer resin), vinylidene resin (vinylidene chloride, vinylidene fluoride). ), Thermoplastic resins such as ethylene-vinyl acetate resin, polyolefin resin, chlorinated olefin resin, ethylene-acrylic resin, petroleum resin, cellulose derivative resin, and the like. Of these, alkyd resins, acrylic resins, polyurethane resins, cellulose derivative resins and ethylene vinyl acetate resins are preferred.
Examples of the colorant used in the ink or paint include dyes and pigments, and any of inorganic dyes and pigments and organic dyes and pigments can be used. Furthermore, it is also possible to use metallic glossy ink containing a metal fine particle obtained from a paste of metal cutting particles or a deposited metal film as a pigment.
Anti-foaming agents, anti-settling agents, dye / pigment dispersants, fluidity modifiers, anti-blocking agents, antistatic agents, antioxidants, light stabilizers, UV absorbers as necessary Further, various additives for the purpose of improving the internal curing agent, scratch resistance and the like can also be added.

(II-2) Support film (pattern layer support or film substrate)
The support film used for the transfer film is not particularly limited, and may be water-soluble or water-swellable. Examples of the material include polyvinyl alcohol, polyvinyl pyrrolidone, acetyl cellulose, polyacrylamide, acetyl butyl cellulose, gelatin, glue, sodium alginate, hydroxyethyl cellulose, carboxymethyl cellulose and the like. Further, these components may be used as the main components, and other monomers such as (meth) acrylamide may be copolymerized, or other resins such as polyurethane resins may be blended.

(III) Protective coating composition The protective coating composition of the present invention comprises a hydroxyl group-containing resin composition (P) and a polyisocyanate curing agent (Q).

(III-1) Hydroxyl-containing resin composition (P)
The hydroxyl group-containing resin composition (P) is obtained by graft polymerization of a resin component (A) containing at least a modified polyolefin resin (a) and a polyol component (B).

Resin component (A)
The resin component (A) contains at least the modified polyolefin resin (a), and may contain other polyolefin resin (a ′) as necessary.
Examples of the modified polyolefin resin (a) include chlorinated polypropylene resin, acrylic modified chlorinated polypropylene resin, maleic anhydride modified polypropylene resin, non-chlorinated maleic acid modified polyolefin resin, and the like. May be used.
Specific examples of the chlorinated polypropylene resin include trade names Super Clone 892L, Super Clone 814H, Super Clone 822 and the like manufactured by Nippon Paper Industries Co., Ltd.
Specific examples of the acrylic-modified chlorinated polypropylene resin include trade name Supercron 240H and Supercron 223M manufactured by Nippon Paper Industries Co., Ltd.
Specific examples of the maleic anhydride-modified polypropylene resin include trade name Supercron 851L and Supercron 930 manufactured by Nippon Paper Industries Co., Ltd.
Specific examples of the non-chlorinated maleic acid-modified polyolefin-based resin include trade names Auroren 100 and Aurolen 200 manufactured by Nippon Paper Chemicals Co., Ltd.
The resin composition (P) contains 1 to 20% by weight, preferably 3 to 18% by weight, of the modified polypropylene resin (a) in terms of solid content. If it is less than the above range, the adhesion to the polypropylene-based resin molded product is reduced and peeling occurs, and if it is more than the above range, the gloss value is greatly reduced and oil resistance cannot be satisfied. Then, the sharpness is impaired and the design properties are completely lost, and the coating film is significantly deteriorated due to oil resistance.
Other polyolefin resins (a ′) include various types of polyethylene such as low density, ultra-low density, and high density, isotactic or syndiotactic polypropylene, propylene / ethylene block or random copolymer, polybutene-1, poly 3- Examples thereof include methyl-1-butene, poly-3-methyl-1-pentene, poly-4-methyl-1-pentene, and cycloolefins.
The other polyolefin resin (a ′) may be added in an amount of 0 to 50 parts by weight with respect to 100 parts by weight of the modified polyolefin resin (a).
Accordingly, the resin component (A) is contained in the protective coating composition in an amount of 1 to 20% by weight, preferably 3 to 18% by weight.

Polyol component (B)
As a polyol component (B), it is preferable that glass transition temperature is 50 degreeC or more, and this condition is very important in the adhesiveness to the polypropylene resin molded product 3 (base | substrate) and the pattern layer 4. FIG. Polypropylene-based resins are hard-to-adhere materials, and in order to make them adhere, the coating system must contain a polypropylene-based resin as well as a coating film strength. In the newly developed product, it is not sufficient to just adhere to the polypropylene resin molded product 3 (substrate with the contained polypropylene resin), and it is necessary to supplement it with a polyol component.
Moreover, since the pattern layer 4 to be transferred is not completely in close contact with the polypropylene resin molded product 3, it is necessary to compensate for this point, and the strength and hardness of the coating film are factors that ensure adhesion. It has become.
The glass transition point temperature will be described in detail. At 45 ° C. or lower, peeling occurs due to the low initial coating strength, and when it is 45 ° C. or higher and lower than 50 ° C., moisture resistance adhesiveness, heat resistant adhesiveness, etc. The secondary adhesion causes undesired peeling and peeling. And since it is in the severe condition with respect to a heat | fever and light in a motor vehicle interior part, especially the front vicinity, it is preferable that a glass transition point is 50 degreeC or more as conditions which can endure them.
As for the adhesion to the polypropylene resin molded article 3, excessive shrinkage due to the crosslinking reaction of the coating film leads to a decrease in adhesion, and therefore the glass transition point is preferably 50 ° C. or higher, more preferably 60 ° C. or higher.

Examples of the polyol component (B) include those containing at least one selected from the group of acrylic polyol, polyester polyol, polycarbonate polyol, polyurethane polyol, and the like, in terms of cost, high appearance, weather resistance, chemical resistance, In view of required performance such as heat resistance, acrylic polyol is preferable.
The acrylic polyol contains an acrylic polyol containing cycloalkyl (meth) acrylate (b), t-alkyl (meth) acrylate (c), styrene (f), and hydroxyalkyl (d) (meth) acrylate. It may be.
Acrylic polyol is cycloalkyl (meth) acrylate (5 to 8 carbon atoms) (b) 5 to 60% by weight, preferably 10 to 50% by weight; t-alkyl (meth) acrylate (4 to 8 carbon atoms) (C) 5 to 60% by weight, preferably 10 to 50% by weight; styrene (f) 5 to 60% by weight, preferably 10 to 50% by weight; and hydroxyalkyl (meth) acrylate (2 to 4 carbon atoms) (D) 3 to 20% by weight, preferably 5 to 15% by weight; and other polymerizable monomer (e) added if necessary 82% by weight or less, preferably 70% by weight or less, more preferably 50 % By weight or less (the total of these components is 100% by weight).

Cycloalkyl (meth) acrylate (b)
Examples of the cycloalkyl (meth) acrylate (b) include cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, cyclooctyl (meth) acrylate, and the like, preferably cyclohexyl (meth) acrylate. .
Cyclohexyl (meth) acrylate is very excellent in compatibility with the modified polyolefin resin (a) and greatly contributes to stability over time. As for the above compatibility, compatibility with extremely low polarity to highly polar acrylic resin and urethane resin is very poor. Even if possible, it may not be possible to obtain uniform atomization in spray coating. Moreover, generation | occurrence | production of a spot on the coating-film surface may be accompanied from the poor solubility. The compatibility is very remarkable at the time of storage stability, paintability, and formation of a coating film, and the physical properties of the coating film cannot satisfy various performances without a uniform coating film. Cyclohexyl methacrylate not only ensures compatibility and stability, but also has excellent transparency of the protective coating. Its high refractive index provides depth and flesh, provides smoothness, and achieves the required appearance quality. Contributed greatly. Furthermore, by greatly reducing the polarity of the resin system, it contributes to adhesion to a plastic molded product made of a polypropylene material having low adhesion and low adhesion.
In addition, it is very excellent for chemical resistance such as water resistance and alkali resistance, weather resistance, and chemical products containing alcohol.
The composition ratio of the cycloalkyl (b) (meth) acrylate in the polyol component (B) is 5 to 60% by weight, preferably 10 to 50% by weight. If it is less than 10% by weight, the transparency is lowered. If it is less than 5%, the transparency is lost and design properties cannot be imparted. On the other hand, if the amount is more than the above range, the deterioration of the coating film due to oil resistance is remarkable, which is not preferable.

T-Alkyl (meth) acrylate (c)
Examples of the t-alkyl (meth) acrylate (c) include tert-butyl (meth) acrylate, tert-octyl (meth) acrylate, and preferably tert-butyl (meth) acrylate.
Like cyclohexyl methacrylate, tert-butyl methacrylate is very excellent in compatibility with polypropylene resins, and greatly contributes to stability over time and required appearance quality.
In addition, it is very excellent for chemical resistance such as water resistance and alkali resistance, weather resistance, and chemical products containing alcohol. In addition, tert-butyl methacrylate has the effect of lowering the viscosity of the resin system, alleviates the increase in viscosity caused by the graft bond with the polyolefin resin, and as a result, enables good workability and paintability during coating, Improves the paintability, leveling properties, and flowability during application.
The composition ratio of the t-alkyl (meth) acrylate (c) in the polyol component (B) is 5 to 60% by weight, preferably 10 to 50% by weight. If it is less than 10% by weight, the transparency is lowered. If it is less than 5%, the transparency is lost, which is not preferable. On the other hand, if it is more than the above range, the coating film deteriorates due to oil resistance, which is not preferable.

Styrene (f)
Styrene has a high refractive index. The high refractive index of styrene is very effective when transparency and sharpness are required as in the present invention, and greatly contributes to the appearance quality. Styrene is not extremely low in SP (solubility parameter) value, but the skeletal element due to the benzene ring partially contributes to compatibility with the polypropylene resin. Styrene is excellent in heat resistance, water resistance and alkali resistance due to the benzene ring in the skeleton. Furthermore, since styrene is an inexpensive raw material, it is useful in paints containing expensive polyolefin resins. In addition, in order to make the transfer molded product have a high appearance specification, it is preferable that the resin used in the protective coating 5 has a low molecular weight. Since styrene has a function of reducing the molecular weight in the polymerization system, the polymerization initiator can be reduced. This is also useful in terms of cost.
The composition ratio of the styrene (f) in the polyol component (B) is 5 to 60% by weight, preferably 10 to 50% by weight, and glossiness, sharpness, etc. required to be 10% by weight or less. Since the design is deteriorated (the appearance is deteriorated), it is not preferable.

Hydroxyalkyl (meth) acrylate (d)
Examples of the hydroxyalkyl (meth) acrylate (d) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth) acrylic acid 2 -Hydroxybutyl etc. are mentioned, Preferably it is 2-hydroxyethyl (meth) acrylate.
The composition ratio of the hydroxyalkyl (d) (meth) acrylate in the polyol component (B) is 3 to 20% by weight, preferably 5 to 15% by weight. If it is less than the above range, the chemical resistance is poor. When too much, adhesiveness falls by hardening shrinkage of a coating film.

Other polymerizable monomer (e)
Examples of the other polymerizable monomer (e) include styrene, α-methylstyrene, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, Iso-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, (meth) acrylic Examples thereof include isopentanyl acid and phenoxyethyl (meth) acrylate.
The composition ratio of the other polymerizable monomer (e) in the polyol component (B) is 82% by weight or less, preferably 70% by weight or less.

Production method of hydroxyl group-containing resin composition (P) The hydroxyl group-containing resin composition (P) is obtained by graft polymerization of at least the modified polyolefin resin (a) and the polyol component (B) in the resin component (A).
When the graft ratio of the polyol component (B) to the modified polyolefin resin (a) is too small, the storage stability is adversely affected.
As a grafting method, a method in which a carboxyl group derived from maleic anhydride in a modified polyolefin resin is partially reacted with a hydroxyl group-containing vinyl monomer, or a hydroxyl group in an acrylic-modified polypropylene resin or the like is partially unsaturated group-containing vinyl. It is obtained by reacting with a monomer.
Specifically, when the resin component (A) is dissolved in a solvent under heating, the monomer constituting the polyol component (B), for example, (cycloalkyl) (meth) acrylate (b), (meth) acrylic acid When t-alkyl (c), styrene (f), hydroxyalkyl (d) (meth) acrylate and other polymerizable monomer (e) added as needed are added and stirred uniformly, It is carried out by adding a radical polymerization initiator and reacting.
In addition, it may be grafted by a chlorine atom extraction reaction with a polymerization initiator such as peroxide.
The hydroxyl group-containing resin composition (P) thus obtained has a hydroxyl value of 10 to 100 mg-KOH / g, preferably 20 to 80 mg-KOH / g. If the hydroxyl value is less than the above range, the coating film performance such as chemical resistance, weather resistance, heat resistance and the like cannot be satisfied. This is not preferable because the moisture adhesion and water adhesion, which are the next adhesion, are significantly lowered.

(III-2) Polyisocyanate curing agent (Q)
The polyisocyanate curing agent (Q) according to the present invention is used for curing the hydroxyl group-containing resin composition (P).
The polyisocyanate curing agent (Q) is composed of a polyisocyanate compound and an amine curing agent that is added as necessary.
Examples of polyisocyanate compounds include aromatic compounds such as tolylene diisocyanate, xylylene diisocyanate, diphenylmethane diisocyanate, aliphatic compounds such as tetramethylene diisocyanate, hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, isophorone diisocyanate, norbornane diisocyanate. An alicyclic compound or the like, specifically, an aliphatic compound is preferable in consideration of weather resistance, chemical resistance, and high appearance, and modified products thereof are also included.
As an example of an aliphatic isocyanate compound, Asahi Kasei Kogyo Co., Ltd. trade name Duranate 24A-100, Duranate TPA-100, Duranate E402-90T and Sumika Bayer Urethane trade names Sumijour N-3300, Sumijoule N-3200 Sumijoule N-75, Nippon Polyurethane Industry Co., Ltd. trade name Coronate HX, Coronate EH, Mitsui Takeda Chemicals trade name Takenate D-165N, and the like.
The ratio of the NCO group of the polyisocyanate curing agent (Q) to the hydroxyl group of the hydroxyl group-containing resin composition (P) is such that the NCO / OH ratio (equivalent ratio) is 0.5 to 2.0, preferably 0.8. ˜1.5. If it is less than 0.8, the chemical resistance and heat resistance are remarkably lowered, and if it is 1.5 or more, the adhesive force is lowered by excessive curing shrinkage of the coating film, which is not preferable.

(IV) Coating When the surface of a conventional transfer molded product is analyzed with an electron microscope, countless holes that can be called gaps can be confirmed, and the pattern layer is not completely in close contact with the polypropylene resin molded product.
Therefore, the protective coating composition of the present invention allows the coating composition to permeate and adhere to the polypropylene resin molded product 3 not only from the pattern layer 4 itself but also from the numerous holes existing on the pattern layer 4. Intended.

  As described above, the coating composition in the present invention is required not only to protect the pattern layer 4 applied on the polypropylene resin molded product 3 but also to impart further designability to the pattern layer 4. Hydroxyl group formed by grafting the resin component (A) composed of the modified polyolefin resin (a) and the polyol component (B) described above in order to give the protective coating transparency, smoothness, and feeling of meat. It is a two-component system in which the containing resin composition (P) is cured and crosslinked with a polyisocyanate curing agent (Q).

Method for Producing Decorative Molded Product Using the above transfer film, the pattern layer 4 of this transfer film is hydraulically transferred onto a polypropylene resin molded product 3 to produce a transfer molded product 2 as shown in FIG. Since the support film is water-soluble when it floats on the water surface in the transfer tank, it gradually dissolves. After the transfer, the support film remaining on the pattern layer is removed by washing with water. Next, as shown in FIG. 2, the protective coating composition is applied so as to cover the polypropylene resin molded product 3 and the pattern layer 4, and is cured by heating to form the protective coating film 5.
Coating method As a coating method for forming the protective coating film 5, there are spray coating, brush coating, roller coating, dipping coating, electrodeposition coating, and the like, and spray coating is preferable because high appearance is required.
The viscosity of the mixed solution at the time of coating is 10 to 15 seconds, preferably 11 to 14 seconds in Ford Cup # 4. After mixing with the specified isocyanate, it is diluted with a suitable organic solvent. If it is 11 seconds or less, repellency frequently occurs on the transfer printing film, and when the object to be coated is tilted, a picture frame phenomenon occurs in which the applied solution flows from the center of the object to be coated to the outside. Therefore, it is not preferable. And when it is 14 seconds or more, the spray atomization property is deteriorated, the slippage to the object to be coated is insufficient, and the smoothness is lacking.
Describing the film thickness of the protective coating at the time of coating, it is 10 to 50 μm, preferably 20 to 40 μm. This is not preferable because it cannot provide design properties. If the thickness is 40 μm or more, problems such as cracking and sagging occur, which is not preferable.
After painting, leave at room temperature for 5-10 minutes and force dry. The drying conditions are 60 to 100 ° C. for 10 to 100 minutes, preferably 65 to 90 ° C. for 20 to 60 minutes, and if the drying temperature is less than 65 ° C. and 20 to 60 minutes, the crosslinking density decreases, and the adhesion The strength, chemical resistance, and heat resistance are also lowered, and it is necessary to extend the drying time. Further, if the temperature is 90 ° C. or higher and 30 to 60 minutes, curing shrinkage accompanying an increase in the reaction rate is caused, and the adhesiveness is lowered.
If it carries out as mentioned above, the decorative molded product 1 is obtained. This decorative molded product 1 includes a transfer molded product 2 obtained by hydraulic transfer of a pattern layer 4 printed or coated on a water-soluble or swellable support film onto a polypropylene resin molded product 3. The protective coating composition 5 is formed by applying the protective coating composition so as to cover at least the pattern layer 4 of the transfer molded product 2 and heat-curing it. The protective coating 5 is preferably provided so as to cover both the pattern layer 4 and the polypropylene resin molded product 3.

  The main purpose of the coating composition of the present invention is to provide transparency and fleshiness and to give a high appearance. However, the coating composition can be colored with a color clear or treated with an extender pigment. However, excessive addition of extender pigments causes a significant decrease in gloss, so the amount added is limited.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples.

(Production of hydroxyl group-containing resin composition (P), Examples 1-2, Reference Examples 1-8)
Into a 1-liter four-necked flask equipped with a stirrer, a cooler, a thermometer, and a monomer dropping device, the component (A) having the composition shown in Table 1 was charged and stirred until the internal temperature reached 85 ° C. Warm and hold at 85 ° C. for 20 minutes. Subsequently, (B) component was dripped over 2 hours, and after completion | finish of dripping, (C) component was added and it superposed | polymerized at 85 degreeC for 2 hours, and obtained the solution of the hydroxyl-containing resin composition (P). This solution was further diluted with toluene. In Table 1, the amount of each component used is expressed in parts by weight.

  To the solution obtained by diluting the obtained hydroxyl group-containing resin composition (P) with toluene and adjusting the viscosity, Sumidur N-3300 as a polyisocyanate curing agent (Q) was added in the amount shown in Table 1.

Production of Transfer Molded Product 2 A patterned layer 4 was applied to the following polypropylene resin molded product 3 using the following transfer film.
As the polypropylene resin molded product 3, untreated surface polypropylene PP-N-AN manufactured by Shin-Kobe Electric Co., Ltd. was molded into a test piece of 6 cm (W) × 15 cm (L) × 3 mm (T).
As a transfer film, Dai Nippon Printing Co., Ltd. hydraulic transfer printing sheet (Curl Fit, thickness 5 to 10 μm, varnish resin is alkyd resin) was used.

(Examples 1-2 and Reference Examples 1-8)
Using the coating composition obtained above, a protective coating film 5 was formed on the transfer molded article 2 obtained above by a spray coating method so that the thickness after coating film formation was 20 to 40 μm. .

The results are shown in Table 1 regarding the appearance, initial adhesion, and secondary adhesion of the protective coating film of the decorative molded product 1 obtained in Examples 1-2 and Reference Examples 1-8.
(1) Appearance: Judging from 60 ° gloss obtained by measuring with a gloss meter, ○ is 90 or more, Δ is 80 to 90, and X is less than 80.
(2) Adhesion: The following adhesion test (gap 1 mm, number of meshes 100) was performed according to JIS K5400 “8.5.1 grid pattern method”.
Initial adhesion: A protective coating film was formed, and the adhesion state after standing at room temperature for 72 hours was measured.
Secondary adhesion:
(2-1) Heat-resistant adhesion: A protective coating film was formed, and after standing for 72 hours at room temperature, the adhesion state after a heat-resistant test at 80 ° C. for 300 hours was measured.
(2-2) Moisture resistance adhesion: After forming a protective coating film and leaving it to stand at room temperature for 72 hours, the adhesion state after a moisture resistance test for 500 hours in an atmosphere of 50 ° C. and humidity of 95% RH is measured.
Both initial adhesion and secondary adhesion are based on the following criteria.
◯ indicates that no trace of peeling is observed, Δ indicates peeling of 1 to less than 10/100, and X indicates peeling of 10 or more / 100.
(3) Oil resistance: After forming a protective coating film, it was allowed to stand at room temperature for 72 hours and then immersed in heptane, which is a low polarity solvent, at room temperature for 1 hour.
○ indicates that the coating film is not deteriorated, Δ indicates that the coating film is slightly deteriorated, and x indicates that the coating film is clearly deteriorated.
(4) Storage stability: The toluene-diluted solution of the hydroxyl group-containing resin composition (P) is allowed to stand at 0 ° C., 20 ° C., 40 ° C., and 60 ° C. Judgment was made visually.

(* 1) Nippon Paper Industries Co., Ltd., chlorinated polypropylene resin (trade name Supercron 892L, chlorination rate 20%, 20% toluene solution)
(* 2) n-butyl acrylate (* 3) iso-butyl methacrylate (* 4) styrene (* 5) tert-butyl methacrylate (* 6) cyclohexyl methacrylate (* 7) 2-hydroxyethyl methacrylate ( * 8) Azobisisobutyronitrile
In Table 1, OHV represents a hydroxyl value.

  From the results shown in Table 1, since Reference Example 1 has a low chlorinated polypropylene resin content of 3% by weight, the adhesion is not sufficient. In Reference Example 2, the appearance is not sufficient because the chlorinated polypropylene resin is too much at 18% by weight. Since Reference Example 3 has a hydroxyl value of 85 mg / KOH and a high crosslinking density, the adhesion is not sufficient. In Reference Example 4, since CHMA is 2.7% by weight, the appearance due to a decrease in transparency is lowered. In Reference Example 5, since t-BMA is 0.0%, the appearance due to the decrease in transparency is deteriorated. In Reference Example 6, since St is 0.0%, the appearance due to a decrease in transparency is deteriorated. Since Reference Example 7 has a glass transition temperature of 50 ° C. or lower, the adhesion is not sufficient. In Reference Example 8, since the glass transition temperature is 40 ° C. or lower, the adhesion is not sufficient.

  For the transfer molded product obtained by hydraulic transfer of the pattern layer to the polypropylene resin molded product, the adhesion with the polypropylene resin molded product, which is difficult to adhere, and further the adhesion with the pattern layer Protective coating film that has excellent coating performance such as water resistance, alkali resistance, oil resistance, weather resistance, impact resistance, hardness, and excellent appearance quality such as sharpness, smoothness, and texture Can provide.

Claims (8)

With respect to a transfer molded product obtained by water-transferring a pattern layer formed by printing or painting on a water-soluble or swellable film base material onto a polypropylene resin molded product, the polypropylene resin molded product and A protective coating composition for producing a protective coating film having adhesion to both the pattern layer,
A resin component (A) containing at least the modified polyolefin resin (a) and a polyol component (B) containing at least one selected from the group consisting of acrylic polyol, polyester polyol, polycarbonate polyol and polyurethane polyol are graft-polymerized. Hydroxyl group-containing resin composition (P),
And polyisocyanate curing agent (Q)
A coating composition for protecting a hydraulic transfer pattern layer.   The protective coating according to claim 1, wherein the modified polyolefin resin (a) is a chlorinated polypropylene, an acrylic modified chlorinated polypropylene resin, a maleic anhydride modified polypropylene, a non-chlorinated maleic acid modified polyolefin resin, or a mixture thereof. Composition.   The resin composition (P) comprises, in terms of solid content, 1 to 20% by weight of a resin component (A) and 99 to 80% by weight of a polyol component (B) (the total of both is 100% by weight). The protective coating composition as described.   The protective coating composition according to claim 1, wherein the polyol component (B) has a glass transition temperature of 50C or higher.   The polyol component (B) is cyclohexyl (meth) acrylate (b) 5 to 60% by weight, t-butyl (meth) acrylate (c) 5 to 60% by weight, styrene (f) 5 to 60% by weight, ( Hydroxyalkyl (meth) acrylate (2 to 4 carbon atoms) (d) 3 to 20% by weight and other polymerizable monomer (e) 82 to 0% by weight added as necessary (the total of these components is 100 The protective coating composition according to claim 1, which is an acrylic polyol composed of   The protective coating composition according to claim 1, wherein the resin composition (P) has a hydroxyl value of 10 to 100 mg-KOH / g.   For the transfer molded product (2) obtained by hydraulically transferring a pattern layer formed by printing or painting on a water-soluble or swellable film substrate onto a polypropylene resin molded product, the polypropylene resin The manufacturing method of the decorative molded product which apply | coats the protective coating composition in any one of Claims 1-6 which has adhesiveness in both a molded product and this pattern layer, and heat-hardens it.   A pattern layer formed by printing or painting on a water-soluble or swellable film base material is transferred onto a polypropylene resin molded product by water pressure transfer, and the polypropylene-based product is transferred to the transfer molded product. A decorative molded product comprising a protective coating film obtained by applying the protective coating composition according to any one of claims 1 to 6 and having heat-curing properties, which has adhesion to both the resin molded product and the pattern layer. .