JPH074821B2 - Method for manufacturing laminated foam board - Google Patents

Description

The present invention relates to a method for manufacturing a laminated foam plate.

[Conventional technology]

Conventionally, when manufacturing a fiber-reinforced laminated foam plate, a plurality of fiber mats such as glass fibers impregnated with a stock solution of a foaming synthetic resin are laminated and passed through a heating foaming furnace while being pressed by a belt conveyor from above and below. A means for continuously foaming is known.

[Problems of conventional technology]

The above-mentioned manufacturing means has the advantage that continuous molding is possible, but when foaming while pressing with the upper and lower belt conveyors,
Porosity is likely to accumulate at the interface of each laminated mat, which facilitates delamination, and since pore marks during foaming remain on the contact planes with the upper and lower belt conveyors, the surface of the molded product is less likely to be smooth, making it of high quality. However, there was a problem that molding was difficult.

[Problems solved by the invention]

In view of the above problems, the present invention has been made for the purpose of obtaining a method for producing a high-quality laminated foam plate by preventing the accumulation of pores and the generation of pore traces between layers and on the front and back surfaces.

[Technology for solving problems]

That is, in the method for producing a laminated foam plate of the present invention, a plurality of fiber mats impregnated with a foaming undiluted solution are laminated and passed through a heating foaming furnace while being pressed from above and below by a belt conveyor to continuously foam the fibers. In the case of producing a laminated foam plate, the plurality of laminated fiber mats are pre-foamed to have a thickness slightly larger than a predetermined thickness before being supplied to the upper and lower belt conveyors, and then the upper and lower belt conveyors are supplied. It is what

[Action]

In the present invention, the foaming undiluted solution is a synthetic resin to which a foaming agent is added, such as urethane resin or phenol resin.

The fiber mat refers to a woven fabric or a non-woven fabric that can be impregnated with the above-mentioned undiluted foaming liquid, and is mainly composed of glass fibers.

In the present invention, the fiber mat impregnated with the foaming stock solution laminated in a plurality of plates is pre-foamed to the above-mentioned thickness before being supplied to a pair of upper and lower belt conveyors facing each other with a predetermined thickness.

Therefore, when it is supplied to the pair of upper and lower belt conveyors, it is always supplied while being compressed. At this time, bubbles staying between the layers or bubbles that can be made to bulge on the front and back surfaces of the foam, The harmful effects of air bubbles when crushed at the time of this supply and narrowed by this belt conveyor are eliminated.

The pre-foamed laminated plate will be naturally compressed by the rolls of the upper belt conveyor 1B as shown in FIG. 1, but if it is desired to increase the compression rate, it is an independent roll that performs only compression. A configuration (not shown) may be provided immediately before the upper belt conveyor 1B and the compression may be performed stepwise.

〔Example〕

 Next, an embodiment of the present invention will be described.

(Example 1) As shown in FIG. 1, a preheating zone 2 was provided immediately before a pair of belt conveyors 1A, 1B facing each other with a distance equal to a set dimension thickness T, and a foaming agent was mixed therein. A stack of three phenolic resin-impregnated glass fiber mats M is supplied and pre-foamed in the pre-heating zone 2 so that the wall thickness T'increases by about 10% with respect to the set dimension, and then a pair of belt conveyors. It was supplied between 1A and 1B, compressed, and then transferred while foaming in the heating foaming furnace 3.

Almost no bubble traces were observed on the surface shape of the product, and almost no bubble retention was observed at the laminate interface of the molded product.

(Example 2) When a foamed urethane resin was used in place of the phenol resin in Example 1 to manufacture a laminated foam plate in the same manner as in Example 1, the same results as in Example 1 were obtained.

〔effect〕

As described above, in the case of manufacturing a laminated foam plate, the present invention can effectively prevent the accumulation of bubbles at each of the laminated interfaces and the front and back surfaces of the laminated plate, and easily form a high-quality molded product. With regard to the above, since it is sufficient to provide a preheating zone in the conventional heating and foaming apparatus, there is an effect that the implementation is easy.

[Brief description of drawings]

FIG. 1 is a side view of an apparatus for carrying out the method of the present invention. 1A, 1B ... a pair of belt conveyors, 2 ... preheating zone,
3 ... Heating foaming furnace

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Claims (1)

[Claims] 1. A method for producing a fiber-reinforced laminated foam plate by laminating a plurality of fiber mats impregnated with an undiluted foaming solution, passing the same through a heating foaming furnace while narrowing the pressure from above and below with a belt conveyor, and continuously foaming. In, before supplying the plurality of laminated fiber mats to the upper and lower belt conveyors, pre-foamed to a thickness slightly larger than a predetermined thickness, and then,
A method for manufacturing a laminated foam plate, which comprises supplying the upper and lower belt conveyors.