JPS5892542A - Manufacture of molding excellent in heat resistance - Google Patents

Abstract

PURPOSE:To obtain a molding excellent in heat resistance ideal for ceiling panels, side wall panels and the like for automobiles free from peeling and blistering in the application under a thermal atmosphere by covering the surface of an urethane foam with a fiber-reinforced thermosetting resin molding material. CONSTITUTION:For example, (A) a fiber-reinforced thermosetting resin molding material comprising (B) (i) a fiber reinforcing agent, (ii) a thermosetting resin (e.g. unsaturated polyester resin) and the like is applied on the surface of an urethane foam and hardened to form a layer. Then, after a through hole is provided extending to the urethane foam from the molding material layer, the layer is dried by heating. The hole is closed with (C) a heat resistant material (e.g. unsaturated polyester resin) and an intended molding is obtained by working. USE:Panel-like molding for hot water storage tank, heat storage or the like and heat insulating panel for building and others.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention covers the surface of urethane foam with a fiber-reinforced thermosetting resin or resin molding material (hereinafter referred to as FRP) to prevent peeling or blistering even when used in a hot atmosphere. The present invention relates to a method for producing molded products with excellent heat resistance.

Conventionally, the core material is urethane foam and the surface material is FRP.
Composite molded products made of thin metal sheets, etc. are often exposed to high-temperature atmospheres of 50°C or higher - ceiling panels and side wall panels of patrol cars, hot water tanks, or i! It is used for panel-shaped molded products such as foothills, cross-sectional panels for construction, etc., but such molded products are prone to volatilization of gas components such as chlorofluorohydrocarbons and carbon dioxide contained in the urethane foam due to temperature rise. This is a serious problem in which peeling and blistering occur at locations where the adhesive strength layer is weak due to swelling and swelling, such as the interface between the surface material and the core material, or the interface between the skin layer and the core layer in the case of injection foam molded products. There is a defective power i. This is especially 80
This is significantly promoted in an atmosphere with a temperature of ℃ or higher.

As a method to improve adhesion between the surface material and the core material by applying an adhesive or primer, or in the case of polyurethane foam molded products with a skin layer, roughening the surface to improve adhesion. is proposed. However, these methods have not fundamentally solved the problem of peeling and blistering.

As a result of intensive research to solve the above problems, the inventors found that by heating urethane foam alone, especially 8
Although heating at temperatures above 0°C is preferable because the amount of volatilization of the contained gas components is extremely large, in order to overcome the drawback that the deformation of the foam becomes significantly large, the urethane foam is heated from the surface of the FRP layer, which is the coating layer of the urethane foam. After making a through hole that extends through the mold and drying it by heating in the range of about 50 to 140'C, sealing it with a heat-resistant material such as W or putty, a molded product that does not peel or blister even when used in a hot atmosphere can be obtained. This discovery led to the present invention.

That is, in the present invention, after coating the surface of a 7-ohm urethane with FRP, the FRP is cured, and then a through hole is provided that reaches the urethane foam from the molding material layer, and after drying by heating, the lock hole is covered with a heat resistant material. Provided is a method for producing a molded article with excellent heat resistance characterized by sealing.

The urethane foam used in the present invention may be any known and commonly used hard urethane foam (generally polyol, polyisocyanate and water, or a blowing agent such as a chlorinated hydrogen chloride foam, a catalyst, a crosslinking agent, and other additive components). The urethane foam can be formed using any commonly used molding method.Also, the state of the foam may be an injection foam with a skin layer or a foam with a skin layer. The shape of the urethane foam can be variously changed depending on the application, such as a plate shape, a car door shape, a ceiling shape, etc.

The FRP used in the present invention contains, for example, a thermosetting resin such as an unsaturated polyester resin, a vinyl ester resin, or a phenol resin. Further, the fiber reinforcing material used in such a molding material is preferably glass fiber or carbon fiber, and other synthetic fibers or metal fibers may also be used depending on the case.

In addition, the ferric acid type material can be used in combination with any known additives such as curing agents, accelerators, fillers, pigments, 11111 agents, and other additives, as required.

The method of coating the urethane foam with FRP used in the present invention can be carried out by coating the FRP on the surface of the urethane foam by a known molding method such as the Handley Atsuno method, the spray-up method, the resin injection method, the press method, or the continuous molding method. I can do it. In addition, in the present invention, the surface of the urethane foam is coated, but when the 7-ohm urethane is in the form of a plate, the sides other than the top and bottom surfaces can be covered with metal plates such as iron plates, steel plates, aluminum plates, etc. or resin plates regardless of the type. It may be covered with something. Depending on the shape of the urethane foam, FR
The area covered by P on the urethane foam is usually 77% or more, preferably 87% or more.

The method for drilling holes in the sand weasel molded product produced as described above may be any commonly used method, such as setting a drill in a hand drill, Luder, drill press, etc. and drilling the holes. The diameter of the pores is not particularly limited, but the smaller the pore diameter is, the better, considering the hole-opening process using heat-resistant material during binding and the appearance of the molded product, but the smaller the pore diameter, the better.
In consideration of a decrease in strength, etc., the range is preferably 3 to 100 degrees.

In the present invention, heating and drying is performed to volatilize the gas component after the hole-opening process, and the temperature conditions at that time are usually 40 to 150℃.
℃ range. If the temperature is low, the volatilization efficiency will be affected and a long time will be required, and if the temperature is high, there will be a problem of decomposition of the urethane foam, so the temperature range is preferably 50 to 140°C.

Next, the molded product is heated and dried, and then subjected to hole-closing processing.
It is best to do this as soon as possible after heating and drying.
If the hole-closing process is delayed, it is best to seal the hole opening with cellophane tape or the like. The heat-resistant material encapsulated in the pore-closing process may be one that is commonly used, such as thermosetting resins such as unsaturated polyester resin and epoxy resin, and fillers, hardeners, and pigments as necessary. , it is possible to mix and use various additives and the like. As such a material, a room temperature curing type is preferable. The hole-closing process is generally carried out by hand, caulking gun, or, if the hole is small, by injecting liquid resin with a syringe or the like.

The sandwich molded product obtained in this way does not peel or blister even when used in a hot atmosphere, and can be used in the form of panels such as ceiling panels and wall panels for automatic military units, hot water tanks, and warm room. It is useful for molding, cross-sectional panels for construction, etc.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples. Parts and percentages in the examples are by weight.

Example-1 Hlpr with a wooden pattern of 500X500X20-0 (m)
ox BQ-550<polyol: Dainippon Ink Chemical Co., Ltd. [) 100s.

A cretan foam bun was produced using a blend of 144 parts of Hlprox S P-299 (crude MDI: manufactured by Dainippon Ink Chemical Co., Ltd.) and 10 parts of Freon-11 (blowing agent: manufactured by Daikin Corporation), and after being left at room temperature for one week, a cutter was used. 50m thick,
A 1000511m" Sumpu foam specimen with a width of 100m and a length of 200KII was cut out. The basic physical properties of this foam are a foam density of 0.103 and a compressive yield point strength of 1α.
7 kg/l (23°C, parallel to the direction of foaming). This foam molded product is made of unsaturated polyester resin (
Polylite PH-12'5: Dainippon Ink Chemical Co., Ltd.) 1
00 parts, 55% methyl ethyl ketone(-oxide(
MEKPO) t2sV added was impregnated into 450 g/- of chopped strand glass mat (manufactured by Nitto Boseki Co., Ltd.) so that the glass content was 50%, and the three sheets were
The top, bottom, and - sides were laminated using a dry-up process, and after being left at room temperature for 48 hours, one through hole with a diameter of 5 squares was made in the center and dried by heating at 120° C. for 2 hours. After drying and cooling, Polylite F) I-123100, 50 talc and MEKPOtS were mixed to make a putty, and the openings were filled with it. The obtained molded product was subjected to a heat resistance test at 0°C for 715 hours.The heat resistance was good as shown in Table 1.

Comparison Example 1 A molded article (plate) without holes in Example 1 was prepared and a heat resistance test was conducted. As a result, as shown in Table 1, blisters appeared on the entire surface.

Example 2 A molded product was obtained in the same manner as in Example 1 except that the heat drying conditions were changed to a temperature of 80° C. and a drying time of 5 hours. The results of the heat resistance test of the obtained moldings are shown in Table 1.

Comparative Example 2 A molded product corresponding to the non-perforated molded product in Example 2 was obtained and its heat resistance test was conducted. The results are shown in Table-1.

Examples 6 and 4, Comparative Example 3 As shown in Table 1, molded products were obtained in the same manner as in Example 1 except that the shape of the urethane foam or the heat drying conditions were changed.

Also, for comparison, the above molded product was obtained without opening the holes (・
A molded product was obtained. The results of these heat resistance tests are shown in Table-1.

Example-5 Example except that the amount of 7-11 added was changed to 22 parts-
A 7-ohm urethane was produced in the same manner as in Example 1. The basic physical properties of this foam are the foam density (1.05g/C♂
The pressure yield point strength was 41 kl/e-. Using this foam, a molded article was obtained in the same manner as in Example 1) 11-1. The test results are shown in Table-2.

Comparative Example 4 A molded product corresponding to the non-perforated molded product in Example 5 was obtained, and a heat resistance test was conducted on the molded product. The results are shown in Table-2.

Example 6 A molded product was obtained in the same manner as in Example 5 except that the drying time was changed to 5 hours. The results of the heat resistance test are shown in Table-2. , Example 7 A molded product was obtained in the same manner as in Example 5 except that the shape of the urethane foam and the diameter of the through hole were changed. The results of the heat resistance test are shown in Table-2.

Example 8 A urethane foam having a thickness of 31 cm, a medium diameter of 20 cm, and a length of 201 cm was prepared in the same manner as in Example 1. This foam was placed in a compression mold, and the upper, lower, and side wall surfaces were formed. Two 45011/- continuous glass mats (manufactured by Asahi Fiber Co., Ltd.) impregnated with the same unsaturated polyester resin compound as that used in Example 1 (manufactured by Asahi Fiber Co., Ltd.) were placed on the walls, and pressure was applied. 10kpi/cy
Compression molding was performed at a temperature of 50°C for 10 minutes. The resin comparand used at this time was Polylite PM-141 (unsaturated polyester super fat: manufactured by Dainippon Ink Chemical Co., Ltd.) 100
parts, weight calcium carbonate 50 parts, 55% MEKPO10
part and 0.6 part of 6% cobalt heptathenate. Hereinafter, molded products were obtained in the same manner as in Example-1. The results are shown in Table-2.

Comparative Example 5 A colored product corresponding to Example 6 without openings was obtained, and a heat resistance test was conducted on the colored product. The results are shown in Table-2.

Claims (1)

[Claims] After coating the surface of the urethane foam with a fiber-reinforced thermosetting resin molding material, curing the wrinkle molding material, and then providing a through hole that reaches the urethane foam from the molding material layer and drying it by heating. A method for producing a molded product with excellent heat resistance, characterized by sealing a lock hole with a heat-resistant material.