Dai Nippon Toryo Co., Ltd.

Ube Machinery Corporation, Ltd.

Prime Polymer Co., Ltd.

Kenji Oota

Kenji Yonemochi

Toshio Arai

Etsuo Okahara

Kazuaki Kobayashi

Yoshiaki Yamamoto

Takeshi Minoda

Kaoru Yorita

Yuichi Matsuda

Takashi Okusako

Etuo Okahara

Shinichirou Shiroza

An in-mold coating method providing a mold having a specifically formed auxiliary cavity and an in-mold coating formation method which employs said mold, so that it is possible to prevent a coating material from leaking out of the mold, thereby shortening the molding formation cycle, and making it possible to manufacture a molded product having a stabilized quality. In addition, by using a mold having a specifically shaped sub-cavity, there is provided a still further in-mold coating formation method which can keep mold temperature at a relatively low value, cause the coating material to cure at a predetermined temperature and within a predetermined time period thereby shortening the molding formation cycle, improving the productivity, improving the physical properties of a coating layer, thus obtaining a good molded product.

Method of forming a coating layer on the surface of a molded product within a mold

An in-mold coating apparatus providing a mold having a specifically formed auxiliary cavity and an in-mold coating formation method which employs said mold, so that it is possible to prevent a coating material from leaking out of the mold, thereby shortening the molding formation cycle, and making it possible to manufacture a molded product having a stabilized quality. In addition, by using a mold having a specifically shaped sub-cavity, there is provided a still further in-mold coating formation method which can keep mold temperature at a relatively low value, cause the coating material to cure at a predetermined temperature and within a predetermined time period thereby shortening the molding formation cycle, improving the productivity, improving the physical properties of a coating layer, thus obtaining a good molded product.

A process producing an in-mold coated molded product. The process molds a thermoplastic resin material under a mold-clamping pressure in a mold including a fixed mold part and a movable mold part each heated at a predetermined temperature, separates the fixed mold part and the movable mold part when the molded material surface is solidified such that it is durable to a pressure of injection and flow of a coating agent, and injects the coating agent containing a thermosetting resin material between an inner surface of the mold and the molded product obtained. The process also coats the molded product surface with the coating agent as the mold is re-clamped after injecting the coating agent, takes out the molded product coated with the coating agent when the coating agent is cured such that it is neither peeled off nor cracked by opening the mold, and re-heats the molded product after taking it out.

Method of manufacturing formed product coated in mold

An in-mold coating molded article is obtained by coating the surface of a resin molded product comprising a hydroxyl group-containing polypropylene resin composition (A) with a paint composition for in-mold coating, wherein the composition (A) comprises a polypropylene resin (i), an additive rubber (ii) and optionally a polymer compound (iii) other than the polypropylene resin (i) and the additive rubber (ii), the total hydroxyl value of the polypropylene resin (i), the additive rubber (ii) and the optional polymer compound (iii) is from 1 to 40, the composition (A) has a rubber component content (total of the amount of the additive rubber (ii) and the amount of components soluble in n-decane at 23&#xb0; C. of the polypropylene resin (i) and the optional polymer compound (iii)) of from 15 to 80% by mass based on 100% by mass of the total amount of the rubber component and the resin component other than the rubber component, the paint composition comprises a vehicle component comprising 10 to 70% by mass of an oligomer having at least two (meth)acrylate groups and 90 to 30% by mass of an ethylenically unsaturated monomer copolymerizable with the oligomer, a (meth)acryl modified chlorinated polyolefin having a chlorine content of from 2 to 40% by mass, an organic peroxide polymerization initiator, and a polyisocyanate compound.

Molded object obtained by in-mold coating and process for producing the same

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Iwakura, Japan

Kenji Oota