JPH0438573B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for film lamination on irregularly shaped extrusion molded products, and is applicable to molded products with complex cross-sectional shapes and In particular, it is possible to easily and inexpensively laminate a film even to a thin-walled hollow extrusion molded product.

The following techniques are generally known for film lamination on irregularly shaped extruded products.

(1) A method in which a laminating film is pressed onto the surface of the molded product using a roll that matches the shape of the molded product, either after the molded product leaves the sizing device or until it has cooled down.

(2) When the molded product comes out of the die and enters the sizing device, a laminate film is simultaneously inserted and bonded inside the sizing device.

These two methods are well known, but each has the following drawbacks.

In the case of method (1), it is easy to obtain uniform adhesive strength because the pressure is applied using rolls that match the shape of the molded product, but there are restrictions on the shape of the molded product to which this method can be applied. In other words, when the (cross-sectional) shape of a molded product becomes complex, it is often impossible to manufacture a pressure roll that matches that shape, and this method is not suitable for thin-walled hollow extrusion molded products. When applied, if the molded product is pressed before it has completely cooled, the molded product will be crushed, making it difficult to obtain a film-laminated molded product in the desired shape. In addition, many additional facilities are required, which tends to increase costs.

In the case of method (2), the (cross-sectional) shape of the molded product that can be film laminated has a much wider range of applicability than method (1). It is also advantageous from an equipment standpoint. However, fundamentally, the low pressure during close contact,
This method suffers from the problem of non-uniformity, and the resulting film laminate molded product has large variations in adhesive strength, and requires a step of pre-applying an adhesive to the laminating film. or,
In the case of hollow extrusion molded products, the compression force is significantly reduced, making it almost impossible to apply this method.

As described above, with regard to the film lamination method in profile extrusion molding, the current technology has considerable limitations in terms of the shape of the molded product.

The present invention overcomes the problems of current technology and reduces this limitation.

The mechanical method of film lamination in the present invention is similar to the method (2) of the prior art described above, in which a laminating film is inserted when the molded product comes out of the die and enters the sizing device. It is something to do. At this time, if a well-known vacuum sizing device is used as the sizing device, and a thermoplastic resin film that has been made breathable by an appropriate method such as drilling holes is used as the laminating film, the film will be plasticized in the sizing device. The molded product is crimped inside the sizing device by the degassing force of vacuum sizing (because the laminating film covering the molded product has air permeability). At this time, the thermoplastic resin film that covers the molded product as a laminating film is softened to some extent by the heat transmitted from the molded product, so the molded product is crimped into the sizing device by the force applied to it. Adhesively integrate with the molded product according to the internal shape of the sizing device.

By using this method, even if the shape of the extrusion molded product is quite complex, it is possible to easily laminate the product with high adhesion. Further, even for thin-walled hollow extrusion molded products, film lamination can be easily performed simultaneously with extrusion.

All extrusion equipment, raw materials, and laminating films that have been conventionally used in profile extrusion fall within the scope of the present invention. Further, as a method for imparting air permeability to a film for lamination, it is considered that the easiest and most common method is to use a perforation roll to make a large number of fine holes.

The breathability required in the present invention is as follows:
There is some variation depending on the shape of the molded product, the type of raw material, the type of laminating film, etc., but according to the inventors' experiments, it is 500 per 100 c.c. using the measurement method of JIS-P-8177. Good results were obtained with a material having an air permeability of 2 seconds or more.

Next, specific examples of the present invention will be described.
This example illustrates one embodiment of the present invention,
The present invention is not limited to the examples unless it departs from the spirit thereof.

Example In the usual profile extrusion molding of hard vinyl chloride resin, when extruding a hollow molded product as shown in Figure 1, a 0.1 mm thick polyvinyl chloride resin was coated on the back side as an adhesive in advance. It is a vinyl film and is JIS-P by a perforated roll.
-8177 measurement method to have an air permeability of 50 seconds per 100 c.c. When inserted into a vacuum sizing machine together with the hollow molded product, it was found that the product was completely sealed with no adhesion or lifting. An integrated film laminate molded article was obtained.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of a molded product obtained by the method of the present invention. 1...Hollow molded product, 2...Film for lamination.

Claims (1)

[Claims] 1. In profile extrusion molding, when surface decoration is applied to the molded product by film lamination, a known vacuum sizing device is used for the sizing part, and the film for lamination is made air permeable by an appropriate method such as drilling in advance. Immediately after extrusion molding, the thermoplastic resin film is inserted into the vacuum sizing device together with the molded product, and the molded product is vacuum sized and at the same time the molded product and the laminating film are brought into sufficient contact with each other. A film lamination method for irregularly shaped extrusion molded products.