JPH0225073B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in reinforced synthetic resin molded products for building materials, specifically rain gutters, corrugated plates, pipes, and angles obtained using thermoplastic synthetic resins (hereinafter simply referred to as thermoplastic resins). Sandwich is a long molded product such as a thermosetting synthetic resin (hereinafter simply referred to as thermosetting resin) layer supported by a paper base material mainly made of vegetable paper. It relates to a molded product with a composite integrated structure. The thermosetting resin layer of the present invention functions as a core material that prevents thermal deformation and shrinkage of the thermoplastic resin that is the substance of the molded product, thereby reinforcing the thermal strength and mechanical strength. Then, this thermosetting resin layer is heated to a temperature sufficiently higher than the curing temperature in a semi-cured state and joins in surface contact as a molten material of thermoplastic resin, which is supplied to the manufacturing process. Since both resins undergo the same curing process, the interfacial adhesion strength between the two resins is maintained well after curing, so that the above-mentioned reinforcing effect is reliably guaranteed.

Conventionally, as a structure to prevent such thermal deformation, there is a structure in which an iron plate or wire mesh is integrally enclosed within the thickness of the molded product. In order to embed the reinforcing core into molding, there is a problem in the process of applying appropriate surface treatment to the surface of the reinforcing core and applying an appropriate adhesive, and since the reinforcing core is heavy, the weight of the molded product itself increases. Problems remain, such as the fact that the reinforcing core at the cut end of the molded product is easily rusted and corroded. In view of these points, Japanese Patent Publication No. 12825/1983 proposed a rain gutter made of extruded thermoplastic resin, in which a thermosetting resin liquid was applied to both the front and back surfaces and cured. From a general perspective, it is disadvantageous in terms of productivity because it includes the step of applying a thermosetting resin liquid to the molded rain gutter having a curved surface, and the step of curing it by heating.
There is a drawback that the flexibility of the entire molded product is offset by the presence of rigid thermosetting resin layers on both the front and back surfaces.

The present invention has been made to improve the above-mentioned problems, and in terms of extrusion molding, the thermosetting resin layer is compositely integrated into the thickness of a thermoplastic resin extrusion molded product in a sandwich-like manner. holds a thermosetting resin liquid supported on a paper base material mainly made of vegetable paper, in which one of the reactions of condensation, polymerization, and polycondensation has progressed to a certain extent, in the corresponding part of an extrusion mold, An extrusion melt of a thermoplastic resin heated and melted at a temperature higher than the curing temperature of the resin is added thereto to form a composite body. The paper base material is mainly paper that belongs to the traditional concept of vegetable fibers such as kraft paper, western paper, Japanese paper, and paperboard.In addition to using these papers alone, these papers and glass fibers, Combinations with inorganic fibers such as carbon fibers, asbestos fibers, and gypsum fibers, organic fibers such as polyester fibers, nylon fibers, and polyvinyl fibers, and metal fibers, and combinations with nonwoven fabrics, woven fabrics, matte, etc. that are processed products of these fibers. Moreover, the base material can also have a multilayer structure. The present invention will be described in detail below with reference to preferred embodiment drawings; Fig. 1 is a flowchart showing an example of the manufacturing process of the molded product of the present invention for a rain gutter, and Fig. 2 is a schematic diagram of the same flowchart. 3 is a longitudinal sectional perspective view of the obtained molded product, taking a rain gutter as an example, and FIG. 4 is an enlarged view of the portion shown in FIG. 3.

The manufacturing process for obtaining the molded product of the present invention will be explained with reference to FIGS. 1 and 2. The base material preparation step (A) is a step of selecting the base materials to be used alone or in combination. As the paper base material, a paper base material (mainly kraft paper) is used because it has a large amount of resin absorption, has suitable stiffness, and is inexpensive. In principle, this paper base material alone is used, but if it is desired to make the resin layer thicker, it is also possible to laminate multiple sheets. In order to supplement the mechanical strength of the resin layer, existing inorganic fibers, organic fibers, or a combination of both may be mixed and combined with the paper base material, and nonwoven fabrics, woven fabrics, and processed products of these fibers may be used. A combination of net and mat is also possible. In either case, these combination base materials shall be selected as appropriate in view of the strength required of the resin layer.

In the thermosetting resin liquid impregnation step (B), the above paper base material is
Phenol resin, melamine resin, epoxy resin,
Solution type resin liquid of resin raw materials such as urea resin, unsaturated polyester resin, diallyl phthalate resin, etc. or partial modification of these resins (e.g. rubber modification)
This is a step of impregnating the resin into an emulsion type resin liquid. When using a combination of inorganic fibers, organic fiber chips, or processed products thereof in addition to a pure paper base material such as kraft paper, the entire combined base material may be immersed in a resin liquid. By impregnating only pure paper with resin liquid and laminating the fibers or their processed products with resin-impregnated paper base material without paper treatment, the resin liquid is transferred from the base material and it is treated as if it were impregnated with resin liquid. It can also be made into something equivalent to fiber or a processed product thereof. Instead of the resin liquid impregnation method, paper fibers are treated with resin (sizing treatment) during paper making, and a resin film made of an untreated paper base material and an initial hardened thermosetting resin is laminated. This can also be adopted. The aging step (C) is to dry the resin by leaving the impregnated resin solution at room temperature, but this step (C) is not necessary when a resin-free method is used. The step (D) of feeding out a single sheet or a plurality of sheets of paper base material that has been impregnated and dried with resin is carried out by impregnating resin from two respective paper base material rolls R ₁ and R ₂ as shown in Fig. 2, for example. Pay out the dry base materials 1, ... and pinch roll them.
The upper and lower layers are integrally laminated by R ₃ and R ₄ . Of course, the base materials 10 include those that are not impregnated with resin by the above-described method. The preheating step (E) imparts semi-curing properties to the thermosetting resin [however, "semi" does not necessarily mean half, but is a relative adjective indicating the state of a portion (cured) relative to fully cured], and is then treated as described below. The base material 11 is passed through a heater H to perform preliminary heating to ensure complete curing within the mold. When a resin film is used, the film is melted in this step and is impregnated into the base material for partial curing. process
Following (E), the base material 11 is sent into the preforming mold PM to be preformed into a rain gutter shape [Step
(F)〕. If the molded product is flat, it may be preheated, but this preforming is not necessary. In the mold introduction step (G), for example, according to extrusion molding, preforming is performed on a part corresponding to approximately the center of the thickness of the molded product of extrusion mold M, which has a cross die with thermoplastic resin extruder EX. The base material 12 is introduced continuously. In parallel with the introduction of the base material 12, the extruder
The above base material 1 is made by melt extrusion of thermoplastic resin from EX.
When extruding at approximately the same speed as 2 [Step (H)], the heat of the melt extruded material, for example, in the case of polyvinyl chloride, about 180
The curing of the base material 12 proceeds at ~200°C (for example, the curing temperature of melamine resin is approximately 120-160°C, so if the above-mentioned polyvinyl chloride melt at 180-200°C is extruded onto it, It will be appreciated that the curing of the melamine resin progresses).

It is clear that a molded product P in which a thermosetting resin layer is composited within the thickness of the extrusion molded product is obtained through step (H) [step (I)]. Since the resin layer and the thermoplastic resin extrudate are cured in a face-to-face state within the molded part, both can exhibit strong adhesion after curing is completed. It is necessary to select thermosetting resins and thermoplastic resins that have a chemical affinity for each other, but in the case of a low affinity relationship, it is necessary to select thermosetting resins and thermoplastic resins that have a chemical affinity. If necessary, it is preferably employed to improve the activity of the interfacial surface.

The molded product P thus obtained is shown in FIG.
A thermosetting resin layer 10 supported by a paper base material 1 inside the thickness of the main body of the rain gutter G in this example is made into a sandwich-like composite integral piece with the entire surface of the thermoplastic resin extrusion molded material 2, 2. This resin layer 10 prevents the molded materials 2, 2 from elongating in the longitudinal and width directions and shrinking in the same direction due to heat as much as possible, and also strengthens the bending strength and shear strength to some extent. Furthermore, as understood from the explanation of the manufacturing process mentioned above, since both resins cure while in contact with each other, the interfacial adhesion between them is good, so the above reinforcing effect is ensured. Guarantee. Since the entire molded product is obtained using lamination technology, there is no need for a coating process, which is advantageous in terms of manufacturing, as well as the added benefit of being lighter and cheaper than iron plates or wire mesh. Does not cause rust,
In addition, since the reinforcing layer is in the form of paper, it has the additional advantage of being particularly effective in completely reinforcing thin and wide building materials such as corrugated boards and rain gutters. In addition, when polyvinyl chloride is used for the coating layer as illustrated, it is as easy to handle as polyvinyl chloride. It is obvious that many of these benefits are equally promised when the molded product is not only a rain gutter as illustrated, but also a corrugated sheet, a pipe, an angle, and other building materials. Although the above example uses an extrusion molded product as the molded product, the present invention is also applicable to thermoplastic resin molded products made by immersion baking. Further details will be given below with reference to Examples.

Example 1 (a) Paper base material...Two sheets of kraft paper with a thickness of 0.2 mm were impregnated in a melamine resin liquid and aged, and two sheets of glass nonwoven fabric with a thickness of 0.2 mm were placed vertically in the wrong direction with the above kraft paper. They were laminated so as to have the following properties, and were preheated and preformed at 120 to 160°C.

(b) Thermoplastic resin extrusion material...The paper base material of (a) is continuously introduced at a slow speed into a normal cross die for molding rain gutters, and the polyvinyl chloride resin is heated to a melting temperature of 180~180°C in this die. Extrusion molding was carried out at 200°C, and the mixture was combined on both sides of the paper base material to a thickness of 0.7 mm. The resulting rain gutter had a total thickness of 1.3 mm, with a 0.6 mm thick melamine resin layer integrated into the center.

Example 2 (a) Paper base material...4 sheets of kraft paper with a thickness of 0.15 mm were impregnated in a melamine resin liquid and aged, and one sheet of glass matte with a thickness of 0.2 mm was laminated between the kraft papers. Preheating and preforming were performed at 120 to 160°C.

(b) Thermoplastic resin material...After immersing the paper base material in (a) into a polyvinyl chloride resin liquid (paste) while continuously molding it into a rain gutter using a molding machine,
Heated at 200℃ and coated both sides of the paper base with a thickness of 0.4
Combined to make mm. The resulting rain gutter had a total thickness of 1.3 mm, with a 0.8 mm thick melamine resin layer integrated into the center.

Example 3 (a) Paper base material: Two sheets of kraft paper with a thickness of 0.2 mm were laminated on top and bottom (similar to Example 1), impregnated with melamine resin and dried, preheated at 120 to 160°C, and then subjected to wave treatment. It was preformed into a plate shape.

(b) Thermoplastic resin extrusion material: Thickness is applied to both sides of the above pre-formed paper base material using acrylic resin.
0.25mm extrusions are merged to create a total thickness of 1.0mm.
An acrylic resin plate of mm was obtained. This product is optically unique because it contains melamine resin layers with different refractive indexes inside the transparent corrugated plate.

[Brief explanation of drawings]

Fig. 1 is a flowchart showing an example of the manufacturing process of the molded product of the present invention for a rain gutter, Fig. 2 is a schematic diagram of the same flowchart, and Fig. 3 is a flowchart showing an example of the manufacturing process of the molded product of the present invention, using a rain gutter as an example. FIG. 4 is an enlarged view of the portion shown in FIG. 3. (Explanation of symbols), 1, 11, 12...Paper base material,
10... Thermosetting resin layer, 2... Thermoplastic resin extrusion molding material, G... Rain gutter, P... Molded product.

Claims (1)

[Scope of Claims] 1. A building material in which a thermosetting synthetic resin reinforcing layer supported on a paper base material mainly made of vegetable paper is integrally integrated in a sandwich-like manner within the thickness of a thermoplastic synthetic resin molded product. Reinforced synthetic resin molded product. 2. The molded product according to claim 1, wherein the paper is mainly kraft paper or paperboard. 3. The molded product according to claim 1, wherein the paper base material further contains a chop of either inorganic fiber or organic fiber or a processed product thereof. 4 The processed products of the above fibers are nonwoven fabrics, woven fabrics, nets,
The molded product according to claim 3, which is any one of matte.