JP2887234B1 - Method for producing paper-laminated three-dimensionally shaped article reinforced by resin impregnation - Google Patents

Abstract

An object of the present invention is to provide a method for producing a three-dimensionally shaped article having a laminated paper reinforced by impregnation with a resin, which is capable of producing a three-dimensionally shaped article having a sufficient practical strength by impregnating and curing a resin. thing. SOLUTION: A laminated base paper obtained by laminating and integrating a plurality of thin papers via a synthetic resin-based adhesive is formed into a paper laminated three-dimensional molded article having a predetermined shape. After drying at a temperature equal to or lower than the softening temperature of the adhesive, immersed in a resin impregnating solution containing a thermosetting resin as a main component while maintaining the vacuum state, and then the paper laminated three-dimensionally shaped article is subjected to normal pressure. Or, after the resin is impregnated into the paper-laminated three-dimensionally shaped article by applying a pressure of normal pressure or higher, the resin is removed from the resin impregnation liquid, and then the paper-laminated three-dimensionally shaped article is heated to a temperature equal to or lower than the softening temperature of the adhesive. The thermosetting resin is cured by heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a three-dimensionally molded article having a sufficient practical strength by impregnating a resin, and a method for producing a three-dimensionally molded article having a resin reinforced by impregnation with a resin. It is.

[0002]

2. Description of the Related Art Conventionally, in the field of plastic molding and various casting techniques, prior to the final production of a final product, a three-dimensional model formed with a wooden mold or a plaster mold has been prepared, and the moldability and strength of the final product have been prepared. Rough checks such as confirmation and design are widely performed. Especially recently,
For the purpose of shortening the time required to produce a model and reducing costs, a three-dimensional C
A method of using a paper laminated three-dimensionally shaped article molded by an AD system has also been proposed.

[0003] However, conventional wooden molds, gypsum molds, and paper laminated three-dimensionally shaped products are mainly intended to visually confirm a three-dimensional design shape that is difficult to appear in drawings, and the final product. It was not possible to accurately check the moldability and strength of the product close to the actual product and perform it accurately. In the case of a model such as a mold for plastic products, for example, there is a demand to actually mold a final product using this model, but it is almost impossible in terms of strength such as heat resistance and durability. There was a problem that it was possible.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and has sufficient strength such as heat resistance and durability to confirm the same strength as the final product. A method for manufacturing a three-dimensionally shaped article with resin impregnated that can efficiently produce a three-dimensionally shaped article with a laminate that can shorten the production period and significantly reduce the production cost. It was completed for the purpose of doing.

[0005]

Means for Solving the Problems In order to solve the above-mentioned problems, the method of the present invention for producing a three-dimensionally shaped paper laminated article reinforced by impregnation with a resin comprises bonding a plurality of thin papers to a synthetic resin system. The laminated base paper laminated and integrated via the agent is formed into a paper laminated three-dimensional molded article having a predetermined shape, and then the paper laminated three-dimensional molded article is dried under vacuum at a temperature equal to or lower than the softening temperature of the adhesive. Then, immersed in a resin impregnating liquid containing a thermosetting resin as a main component while maintaining the vacuum state, and then press the paper laminated three-dimensional molded article under normal pressure or above normal pressure to form a paper laminated three-dimensional molded article. After the resin is impregnated in the resin, the resin is taken out of the resin impregnating liquid, and then the paper laminate three-dimensionally shaped article is heated to a temperature equal to or lower than the softening temperature of the adhesive to thermally cure the thermosetting resin. It is assumed that.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below. The paper laminated three-dimensionally shaped article in the present invention is an experimental model, a wooden mold substitute, a simple mold for injection molding, or the like. First, a thickness of about 0.04 to 0.4 mm based on three-dimensional CAD data in advance. Is cut out into a predetermined shape, and a plurality of the sheets are laminated and integrated by sequentially laminating them via a thermoplastic synthetic resin-based adhesive, and the laminated base paper is formed into a predetermined three-dimensional shape. And, in the present invention, the paper laminated three-dimensionally shaped article is dried under vacuum at a temperature lower than the softening temperature of the adhesive, and the thermosetting resin is preliminarily vacuum degassed under vacuum under the same conditions as a main component. Completely immersed in the resin impregnation solution to be used.

[0007] In this case, the paper laminated three-dimensionally shaped article is dried under vacuum in order to promote the impregnation of the resin, which is a subsequent step, and the present inventor has determined that the water vapor pressure of the water in the paper should be reduced. It is based on the result of elucidating that it is a factor that hinders the impregnation of the steel. The vacuum condition is that the degree of vacuum is 4 torr
It is preferable to dry under the following vacuum. If the degree of vacuum is higher than this, sufficient resin impregnation cannot be performed accurately, and sufficient heat resistance and durability that can withstand practical strength cannot be obtained. The reason why the drying is performed at a temperature lower than the softening temperature of the adhesive is to prevent the paper laminated three-dimensionally shaped article from being deformed by the softening of the adhesive and to prevent the surface from being cracked.

The resin impregnating liquid containing a thermosetting resin as a main component includes, for example, a thermosetting resin such as an epoxy resin, a phenol resin or an unsaturated polyester resin as a main component, and an aliphatic amine, A curing agent such as an aromatic amine, an acid anhydride or a tertiary amine is added, and if necessary, a diluent or an accelerator is added in an appropriate amount. Used. The vacuum deaeration is preferably performed at a temperature equal to or higher than the drying temperature of the three-dimensionally shaped paper laminated product, and at a degree of vacuum equal to or lower than the degree of vacuum during the drying. Then, the impregnation of the resin is further promoted by the vacuum degassing.

Next, the resin is returned to normal pressure or is pressurized to normal pressure or higher, and the resin is impregnated into the three-dimensionally shaped paper laminated product by atmospheric pressure or the like. In this step, for example, the three-dimensionally shaped paper laminated product was immersed in a resin impregnating liquid under vacuum in a vacuum tank, but the vacuum state was released by operating a valve or the like, so that the impregnation was performed by the action of atmospheric pressure. Processing can be performed. At this time, since the paper laminated three-dimensionally shaped article has been subjected to a drying treatment in a vacuum in a previous step to remove water in the paper, the vapor pressure of the water does not hinder the impregnation of the resin. Resin impregnation will be achieved.

[0010] Finally, the paper laminated three-dimensionally shaped article is taken out of the resin impregnating liquid and heated to a temperature lower than the softening temperature of the adhesive to thermally cure the resin. Thus, it is possible to obtain a paper-laminated three-dimensionally shaped product which is excellent in durability and durability, and is impregnated with a resin of a predetermined size without a change in shape. The reason why the thermosetting is performed at a temperature lower than the softening temperature of the adhesive is to prevent the paper laminated three-dimensionally shaped article from being deformed by the softening of the adhesive and to prevent the surface from being cracked.

[0011]

(Example 1) A thermoplastic adhesive is applied to one side of a thin paper having a thickness of 0.1 mm cut out into a predetermined tomographic shape based on three-dimensional CAD data, and is laminated by pressing with a hot roller. A paper laminated three-dimensionally shaped product for a pump part experimental model having a predetermined three-dimensional shape is prepared. Next, the three-dimensionally shaped paper laminated product is dried at 55 ° C., which is lower than the softening temperature of the adhesive, in a vacuum having a degree of vacuum of 4 torr or less.
This was subsequently immersed under vacuum in a resin impregnating liquid containing a thermosetting resin as a main component, which was previously degassed under vacuum. As the resin impregnating liquid, 100 parts by weight of epoxy resin, curing agent 124
A mixture of 20 parts by weight, 20 parts by weight of a diluent, and 2 parts by weight of an accelerator was used. Next, the pressure is returned to normal pressure, and the resin is impregnated in the paper laminated three-dimensionally shaped article by atmospheric pressure. Then, the resin is put into a heating furnace set at 55 ° C. which is equal to or lower than the softening temperature of the adhesive, and the resin is thermally cured. A paper-laminated three-dimensionally shaped product impregnated with resin for a component experimental model was obtained. The resulting tensile strength of the horizontal direction in the paper stacking direction of the shaped articles were, compared to the tensile strength of the shaped article is not impregnated with conventional resin was 0.1kgf / mm ^2, 1.0kgf / it is large enough to carry out the practical strength test as mm ^2, it was possible to perform a highly accurate strength test before entering the production.

(Example 2) In the same manner as in Example 1, a three-dimensionally shaped paper laminated product reinforced by impregnation with a resin as a wooden mold substitute was molded. Since the obtained molded article was excellent in tensile strength and heat resistance, it had sufficient performance as a wooden mold substitute.

(Example 3) In the same manner as in Example 1, a three-dimensionally shaped paper laminated product reinforced by impregnation with a resin for an injection mold model was formed. Since the obtained molded article has excellent tensile strength and heat resistance, injection molding of dozens of plastic products can be actually performed using this mold,
Quality checks such as the strength and appearance of actual products became possible, and the production process was greatly improved.

[0014]

As is clear from the above description, the present invention has sufficient strength such as sufficient heat resistance and durability, can confirm the same strength as that of the final product, and can be manufactured during the manufacturing period. It is possible to efficiently produce a paper laminated three-dimensionally shaped product capable of shortening the production time and significantly reducing the production cost. Therefore, the present invention greatly contributes to the development of industry as a method for producing a three-dimensionally shaped paper-laminated article reinforced by resin impregnation that has eliminated the conventional problems.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification code FI B29K 311: 12 (58) Fields investigated (Int.Cl. ⁶ , DB name) B29D 12 / 00,22 / 00,31 / 00 B29C 33/40 B29C 67/00 B44D 2/00

Claims (7)

(57) [Claims] 1. A laminated base paper obtained by laminating and integrating a plurality of thin papers via a synthetic resin-based adhesive to form a paper laminated three-dimensionally shaped article having a predetermined shape. After drying at a temperature equal to or lower than the softening temperature of the adhesive, the substrate is immersed in a vacuum in a resin impregnating liquid containing a thermosetting resin as a main component. After the resin is impregnated in the paper-laminated three-dimensionally shaped article by reducing the pressure or above the normal pressure, the resin is removed from the resin impregnation liquid, and then the paper-laminated three-dimensionally shaped article is heated to a temperature lower than the softening temperature of the adhesive. A method for producing a three-dimensionally shaped paper-laminated article reinforced by resin impregnation, characterized in that the thermosetting resin is thermally cured by heating the resin. 2. The method according to claim 1, wherein the resin impregnating liquid containing a thermosetting resin as a main component is vacuum degassed in advance. 3. The resin impregnated liquid is reinforced by the resin impregnation according to claim 2, wherein the vacuum deaeration of the resin impregnating liquid is performed at a temperature not lower than the drying temperature of the three-dimensionally shaped paper laminate and not higher than the degree of vacuum at the time of drying. A method of manufacturing a paper laminated three-dimensional shaped product. 4. The method of producing a three-dimensionally shaped paper-laminated article reinforced by resin impregnation according to claim 1, wherein the drying is performed under a vacuum having a degree of vacuum of 4 torr or less. 5. The method according to claim 1, wherein the three-dimensionally molded article is an experimental model, and the three-dimensionally shaped article is reinforced by impregnation with a resin. 6. The method for producing a three-dimensionally shaped paper laminated article reinforced by impregnation with a resin according to claim 1, wherein the three-dimensionally shaped paper laminated article is a wooden mold substitute. 7. The method for producing a three-dimensionally shaped paper laminated article reinforced by resin impregnation according to claim 1, wherein the three-dimensionally shaped article is a simple type for injection molding.