JPS5944209B2 - Manufacturing method of composite molded body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a composite molded body consisting of a thermoplastic synthetic foil and a thermosetting synthetic layer reinforced with glass fibers, such as bathtubs, washbasins, sinks, furniture parts, vehicle articles, etc. Regarding the manufacturing method.

Such a method is known, for example, from Japanese Patent Publication No. 47-48509.

In this method, a layer of glass fiber mat or the like impregnated with a thermosetting synthetic material is first laid on a foil of thermoplastic material. The rolled, unbonded laminate is preheated to the curing temperature of the thermoplastic composite, and the laminate is formed in a mold until the thermoplastic composite foil solidifies. Cool and finally harden the thermosetting synthetic material. A sufficient bond between thermoset and thermoplastic synthetic materials is not taken into account here. This method has the following drawbacks.

The entire laminate must first be preheated to the softening temperature of the thermoplastic synthetic material, thus requiring long preheating times and requiring the inclusion of special set retarders in the thermosetting synthetic material. This is because thermosetting synthetic materials are accelerated in hardening by the influence of high temperatures and can no longer be deformed when actual molding is carried out. Now, in order to form the entire laminate in a mold, the mold is active only on one side, e.g. by applying a vacuum, leaving the opposite side, ie the thermosetting synthetic side, exposed.

The molded laminate must remain in the mold until the thermoplastic synthetic foil has solidified. However, since the glass fiber mat impregnated with thermoset synthetic material acts as a thermal insulator and heat storage, this setting is delayed and overall the cooling time is longer than with thermoplastic foil alone. The molded body is removed from the mold and left for curing of the thermosetting synthetic material. This has the following drawbacks. That is, as mentioned above, while heating precures the thermosetting synthetic material, the molded body is moved, which damages the not yet completely cured portions of the glass fiber reinforced synthetic material.
Scratches occur in the finished moldings and also both layers of the laminate delaminate from each other since no special care has been taken for the bonding of the thermoplastic synthetic foil and the glass fiber reinforced thermoset synthetic layer. There is a risk of The present invention provides a method for producing a composite molded body that does not have these drawbacks. The purpose of the present invention is to first form a preform by molding a thermoplastic synthetic foil into the shape of the final product, and then heat-cure the preform. Before or during the overlapping of the thermosetting synthetic material layers, the surface of the preform facing the thermosetting synthetic material is exposed to a thermoplastic synthetic solvent to partially dissolve the surface, thereby forming the thermosetting synthetic material. pressing the layer onto the surface and forcing the glass fibers of the thermoset synthetic layer into the molten thermoplastic synthetic;
A thermoplastic synthetic material is entangled with glass fibers.

Acrylic monomers, styrene, acetone or methylene chloride can be used as solvents. In the method of the invention, a thermoplastic foil is first heated above its softening point and placed in a mold.

In this case, only the thermoplastic synthetic foil needs to be heated, so
Requires less heating time and heating energy. The softened foil is then inserted into a mold and shaped to produce a preform, which is produced in a short time because the mold cools the molded foil rapidly. The preform removed from the mold is then overlaid with a layer of glass fiber reinforced thermoset synthetic material, with a layer of thermoplastic synthetic material applied to the overlying surface of the preform before or during overlaying. A solvent is provided to dissolve the surface. Therefore, during pressing, the thermoplastic substance becomes entangled with the glass fibers of the thermosetting synthetic material layer, so that even if the thermoplastic synthetic material and the thermosetting synthetic material themselves cannot be directly bonded to each other due to this entanglement, Complete bonding of the thermoplastic synthetic foil and the thermosetting synthetic layer takes place. In this way, the bond between the thermoplastic synthetic foil and the thermosetting synthetic layer is perfected without the risk of pre-curing of the thermosetting synthetic material. can be manufactured in a shorter time than conventionally. In fact, the method according to the invention can be implemented in various ways.

In the simplest case, the overlapping surfaces of the preform are treated with a solvent before superimposing the thermosetting synthetic layer. However, particularly strong bonds can be obtained as follows. That is, solvents are added to the thermosetting synthetic material before or during lamination, such as by adding fillers, polymerization inhibitors, maintaining low temperatures during the curing process, or reducing the amount of hardeners or accelerators added. Curing of curable synthetic materials is delayed. In most cases, compression of the thermoset synthetic material layer is carried out after it has been applied, especially in order to expel trapped gases or bubbles. If curing is delayed, it is
You can wait for pressing for a specific time. According to another embodiment of the method according to the invention, glass fibers, for example as mats, fleeces or in the form of lintels, are made of thermoplastic resin for the reinforcement of the thermosetting synthetic material layer before being embedded in the thermosetting synthetic material. Impregnated with synthetic solvent.

In this case, a glass fiber impregnated with a solvent is first applied to the preform and, if appropriate, after a certain period of time is pressed firmly.
Only then, after a certain time, can a layer of thermosetting synthetic material be applied, whereby some of the glass fibers are embedded in the thermoplastic synthetic material, so that a reinforcement of the transition area of both synthetic materials takes place. Glass fibers impregnated with a thermosetting synthetic material can also be embedded in the thermosetting synthetic material during subsequent layering. With the method according to the invention it is also possible to produce composite moldings which have an outer layer of thermoplastic synthetic foil on both sides.

In this case, the cavities of the double-walled preform made of thermoplastic synthetic material are filled with a thermosetting synthetic material, or the preform is coated with a thermosetting synthetic material and this composite material is preferably reinforced with glass fibers. A further preform of suitable dimensions made of a thermoplastic synthetic material is pressed onto the outer surface of the material layer, and this is treated with a solvent or a thermosetting synthetic material before the further preform is pressed. It is also possible to add a solvent to the layer. Embodiments of the present invention will be described below with reference to the drawings.

The composite molding according to the invention has a preform 1 consisting of a thermoplastic synthetic foil, one outer surface 2 of which forms the surface of the composite molding as the final product. The other side of the preform 1 is exposed to a thermoplastic synthetic solvent before or during the application of the layer 3 of glass fiber-reinforced thermosetting synthetic material, so that the final product is thermosetting. After curing of synthetic materials, there is a transition area 4 which includes thermoplastic synthetics, glass fibers and thermosetting synthetics. On top of layer 3,
Furthermore, layers of the same or other thermosetting synthetic material, with or without glass fiber reinforcement, can also be provided.

[Brief explanation of drawings]

The figure is a cross-sectional view of a part of a composite molded article manufactured by the method according to the present invention. 1...Preformed body, 2...Outer surface, 3.
...Thermosetting synthetic material layer, 4...Transition range.

Claims (1)

[Claims] 1. In a method for manufacturing a composite molded body consisting of a thermoplastic synthetic foil and a thermosetting synthetic layer reinforced with glass fibers, first a thermoplastic synthetic foil is formed into the shape of the final product to form a preform; Before or during the overlapping of the thermosetting synthetic material layer on this preform, the surface of the preform facing the thermosetting synthetic material is exposed to a thermoplastic synthetic solvent to partially dissolve the surface. pressing the thermosetting synthetic material layer against the surface, forcing the glass fibers of the thermosetting synthetic material layer into the molten thermoplastic synthetic material, and entangling the thermoplastic synthetic material with the glass fibers. A method for manufacturing a composite molded body.