JPH05208436A - Manufacture of continuous length molded product - Google Patents

Abstract

PURPOSE:To provide a manufacture of a continuous length molded product having a few deformation by residual strain, by a method wherein the continuous length molded product is coated with a coating sheet is capable of performing desirous decoration. CONSTITUTION:Molten resin 2 is extruded through a mold 12 of an extruding machine 11 using vinyl chloride resin. The temperature of the molten resin 2 on a sticking roll 8 is made 170 deg.C. A vinyl chloride resin sheet on the surface of which the grain of wood is printed is drawn out as a coating sheet 6 and heated by a heater 9 so that the temperature of the sheet becomes 125 deg.C. The coating sheet 6 is stuck to the surface of the molten resin 2 by the sticking roll 8, cooled by a sizing device 13, received by a receiving roll 14, cut off by a cutting device and a coated continuous length molded product is manufactured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a long molded product having a small residual stress in which a covering sheet is coated and laminated on the surface of a long molded product such as a corrugated sheet, a deck material, a pipe and a window frame. The present invention relates to a manufacturing method.

[0002]

2. Description of the Related Art Elongated moldings of thermoplastic resin or thermosetting resin moldings such as corrugated sheets, deck materials, pipes and window frames are generally manufactured by extrusion molding.

For decoration of these long molded products, conventionally, a pigment is mixed in advance with a resin composition for molding to give a single-color decoration, or a long molded product is once produced and then the long molded product is molded. Methods such as printing on the surface of the product in a separate process have been adopted. However, in recent years, these long molded products have become more complex in shape and are more colorful and have a high added value, such as wood patterns and polka dots in their decorated state. The demand for is increasing. In order to manufacture such a long molded product, it has become impossible to deal with the above-mentioned conventional methods.

However, in order to deal with such a point,
It has been proposed to attach a decorative sheet (marking sheet) composed of a thermoplastic resin and an adhesive to the surface of a molded article and a method of attaching the sheet. As an example of the former, for example, as described in JP-A-57-21473, a thin layer of a colored pressure-sensitive adhesive obtained by kneading and dispersing an acrylic pressure-sensitive adhesive and pigment particles, a transparent film having good weather resistance and a release paper are used. A colored pressure-sensitive adhesive sheet sandwiched between and having excellent weather resistance has been proposed.
As an example of the latter, for example, as described in Japanese Patent Publication No. 62-25107, a base material having a sharp recess or drop in the cross-sectional shape of the base material is coated with a synthetic resin such as polyvinyl chloride by mechanical means. A method of attaching a cover sheet such as paper has been proposed.

[0005]

However, JP-A-57-57
When this sheet is applied to a high-temperature base resin using the sheet of 21473, residual stress occurs in the coated product after cooling, and there is a problem that deformation easily occurs during heating or long-term use. is there. Also, Japanese Examined Japanese Patent Publication 62-2510
The method of sticking a sheet as disclosed in Japanese Patent Publication No. 7 requires a large number of man-hours for the sticking step, and if a sheet having high surface hardness is used, this sticking method cannot be adopted.

It is an object of the present invention to solve the above-mentioned conventional problems and to provide a method for producing a long molded product having a desired coating film coated on the surface and having a small residual stress.

[0007]

The present invention is a method for producing a long molded article in which a molten resin is extruded from an extruder and a coating sheet is attached to the surface of the molten resin during or immediately after extrusion molding. The temperature of the coating sheet immediately before being attached to the molten resin is lower than that of the molten resin and the temperature difference is kept within 50 ° C., which is a method for producing a long molded product.

The molding resin used for extrusion molding is
Any commonly used material can be used, for example, polystyrene, acrylic resin, polycarbonate, vinyl chloride resin, polyolefin such as polyethylene and polypropylene, acrylonitrile-butadiene-styrene copolymer (ABS), modified Polyphenylene oxide, polyphenylene sulfide, polyether ether ketone, etc. are used.

Examples of the resin used for the covering molding sheet include vinyl chloride resin, fluorine resin, acrylic resin, polyolefin and the like, which are excellent in surface hardness, surface decoration and weather resistance. Resins that form coatings are preferred.

As the combination of the molding resin and the covering sheet, those which are good in heat fusion or adhesion to each other are appropriately selected. For example, vinyl chloride resin and vinyl chloride resin sheet, acrylic resin and fluorine resin sheet or styrene resin sheet, acrylonitrile-butadiene-
Examples thereof include a combination of a styrene copolymer (ABS) and a vinyl chloride resin sheet, but are not particularly limited. When the heat fusion properties of both are poor, for example, it is preferable to apply a hot melt adhesive to the sheet side in advance.

In the present invention, it is necessary to preheat the coating sheet immediately before being attached to the molten resin so that the temperature is lower than that of the molten resin and the temperature difference is within 50 ° C. If the temperature difference exceeds 50 ° C, the residual stress of the coated long molded product caused by the difference in thermodynamic characteristics between the two cannot be sufficiently removed, and the long-term use or high temperature environment When using, the long molded product may be deformed such as warp due to the difference in shrinkage between the molten resin and the covering sheet.

The method for heating the coating sheet in advance is not particularly limited, such as hot air, infrared rays, and heating rolls, and any method can be appropriately used as long as the coating sheet can be uniformly heated in the width direction.

[0013]

According to the invention of the method for producing a long molded article of the present invention, the temperature of the coating sheet immediately before being attached to the molten resin is lower than that of the molten resin and the temperature difference is within 50 ° C. By applying the heated coating sheet to the surface of the molten resin, the residual stress on both sides can be extremely small, and the difference in shrinkage between the molten resin and the coating sheet is small even after long-term use. Almost no deformation such as warpage.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view illustrating an embodiment of a method for manufacturing a long molded product of the present invention.

Reference numeral 1 is an extrusion molding apparatus, and a die 12 is provided at the tip of an extruder 11. The molten resin 2 continuously extruded from the mold 12 is cooled by a cooling sizing device 13, taken by a take-up roll 14 and cut into an appropriate length to obtain a long molded product.

A coating sheet feeding machine 5 has a coating sheet 6 set therein. The coating sheet 6 continuously fed from the feeding machine 5 passes through the turn roll 7 and is between the die 12 and the cooling sizing device 13, and the die 1
2 is guided to a sticking roll 8 provided so as to come into contact with the molten resin 2 extruded from 2, and is continuously stuck to the surface of the molten resin 2 extruded continuously, as shown in FIG.
The coated long molded product 4 has the coating layer 42 formed on the surface of the molded product body 41.

A heating device 9 is provided between the turn roll 7 and the sticking roll 8 so that the sticking surface of the covering sheet 6 before sticking which is continuously fed can be heated. There is.

In the embodiment shown in FIG. 1, the covering sheet 6 is attached to the surface of the molten resin 2 extruded from the mold 12, but the covering sheet is introduced into the mold during extrusion molding. Alternatively, a coating sheet may be attached to the surface of the molten resin.

In the above embodiment, the molten resin 2
Although the case where the covering sheet 6 is attached to the surface of the molten resin 2 has been described, the shape of the molten resin 2 is not particularly limited as long as the covering sheet 6 can be attached to the surface.
It is also possible to use a molten resin (not shown) having a modified cross-sectional shape such as a U-shaped vertical cross-section, and coat the surface with a coating sheet.

Example 1 By using the apparatus and method shown in FIG. 1, a coating sheet was attached to the surface of a molten resin to produce a coated long molded product.

From the die 12 of the extruder 11, using a vinyl chloride resin as a molding resin, a width of 50 mm and a thickness of 2 mm
The plate-shaped molten resin 2 containing no plasticizer was extruded. The temperature when the molten resin 2 passed through the portion of the sticking roll 8 was 170 ° C.

As the covering sheet 6, a plasticizer-containing vinyl chloride resin sheet having a wood grain printed on the front surface and a polyester hot melt adhesive applied on the back surface is used, and the covering sheet 6 is fed out and heated by a heating device 9. The back surface was heated to a sheet temperature of 125 ° C. still,
The temperature of the heated coating sheet 6 when passing through the portion of the sticking roll 8 was 125 ° C., which was different from the temperature of the molten resin 2 of 170 ° C. by 45 ° C., which was within 50 ° C.

The coating sheet 6 is attached to the surface of the molten resin 2 by the application roll 8, cooled by the cooling sizing device 13, taken by the take-up roll 14 and cut to form the coated long molded product 4. Manufactured.

The obtained coated long molded product 4 is 10 cm in length.
A test piece was prepared by cutting into pieces, and after heating in an oven at 100 ° C. for 1 hour, the heat shrinkage rate was measured and the appearance was observed. As a result, the heat shrinkage rate of the test piece was 0.8%, and as far as the appearance was visible, no deformation such as warpage was observed.

Comparative Example 1 A coated long molded product 4 was produced in the same manner as in Example 1 except that the coating sheet 6 was not preheated by a heating device and was stuck at room temperature (25 ° C.). It was

With respect to the obtained coated long-sized molded product 4, a test piece prepared in the same manner as in Example 1 was measured for heat shrinkage and the appearance was observed. As a result, the heat shrinkage ratio of the test piece was 2.1%, and it was observed that the appearance had warp visually.

Comparative Example 2 A coated long molded product 4 was produced in the same manner as in Example 1 except that the coating sheet was heated to about 100 ° C. by an infrared heating device and attached to the molten resin.

With respect to the obtained coated long molded product 4, a test piece prepared in the same manner as in Example 1 was measured for heat shrinkage and the appearance was observed. As a result, the heat shrinkage rate of the test piece was 1.4%, and it was observed that the appearance had warp visually.

[0029]

[Effect] Since the method for producing a long molded product of the present invention is configured as described above, a coating sheet capable of desired decoration is coated / laminated on the surface of the molded product, It is possible to manufacture a long molded product that is less likely to be deformed due to residual stress.

[Brief description of drawings]

FIG. 1 is a perspective view illustrating an embodiment of the present invention.

FIG. 2 is a partially cutaway perspective view of a coated long molded product manufactured by the method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Extrusion molding apparatus 2 Melt resin 4 Long molded product 5 Feeder 6 Covering sheet 7 Turn roll 8 Adhesion roll 9 Heating device 11 Extruder 12 Mold 13 Cooling sizing device 14 Take-up roll 41 Molded product body 42 Coating layer

Claims (1)

[Claims] 1. A method for producing a long molded product, which comprises extruding a molten resin from an extruder and pasting a coating sheet on the surface of the molten resin during or immediately after extrusion molding, which is pasted onto the molten resin. A method for producing a long molded article, characterized in that the temperature of the immediately preceding covering sheet is lower than that of the molten resin and the temperature difference is kept within 50 ° C.