JPH0212122Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a synthetic resin molding having a foamed layer inside and a non-foamed layer on the outer surface.

[Prior art]

Long synthetic resin moldings having a foam layer inside and a non-foam layer on the outer surface are used in side moldings for automobiles and the like. This kind of molding is manufactured by double extrusion molding, but in order to prevent deformation such as blistering on the outer surface due to gas collection in the non-foamed layer immediately after extrusion, the foamed layer and It has been proposed to provide a gas-impermeable sheet material near the boundary of the non-foamed layer (Utility Model Application Publication No. 164737/1982).

Fig. 1 is a perspective view showing an example of a molding for a vehicle, and Fig. 2 is an A-A showing a conventional molding.
The sectional view, FIG. 3, is a BB sectional view. In the drawing, 1 is a molding, which includes a foam layer 2 formed inside, a non-foam layer 3 provided outside to cover this, and aluminum foil, resin film, etc. provided near the boundary between the two. An end cap 6 is formed at the end of a long material 5 made of a gas-impermeable sheet-like material 4.

However, although such conventional molding 1 is used by being attached to the car body with double-sided adhesive tape or adhesive, the sheet material 4 must be strong enough to prevent deformation due to gas collection in a short period of time immediately after extrusion. is used, so if it is left in extremely hot conditions (e.g. 80 to 90 degrees Celsius) for a long time,
As the gas stored in the foam layer 2 expands,
Since the external non-foamed layer 3 softens, it is pushed up together with the sheet-like material 4 toward the outer surface due to the gas pressure, causing deformation such as blisters 7 as shown in FIG. 4, which impairs the aesthetic appearance. The dot was hot.

It has also been proposed to form a hollow part at the boundary in place of the sheet-like material 4 (Utility Model No. 58).
-164738), this hollow part is formed over the entire area of the non-foamed layer 3, so the molding 1
When attaching to the vehicle body, the outer surface is deformed by crimping, making it impossible to apply a uniform crimping force, and since the hollow part is sealed by the end cap 6, the entire body expands and swells under extremely hot conditions. There was a problem.

[Purpose of invention]

This idea is intended to solve the above problems, and includes providing a gas-impermeable sheet material near the boundary between the foamed layer and the non-foamed layer, as well as forming a ventilation path on the foamed layer side of the sheet material. According to
The purpose is to provide a molding that does not deform even under extremely hot conditions by discharging gas within the foam layer.

[Structure of the idea]

This idea consists of a foam layer formed inside, a non-foam layer formed outside to cover the foam layer, and a gas-impermeable layer provided near the boundary between the foam layer and the non-foam layer. A synthetic resin molding having a foam layer characterized by comprising a sheet material, a ventilation path formed on the foam layer side of the sheet material, and a communication path that communicates the ventilation path to the outside. .

[Example of idea]

Hereinafter, embodiments of this invention will be described with reference to the drawings. FIG. 5 is a partially cutaway perspective view from the back of a molding according to an embodiment of the invention, FIG. 6 is a perspective view showing a part of the sheet-like material, and FIG. 7 is the same as FIG. 1. It is a BB sectional view of the first
The same reference numerals as those in the figures to FIG. 4 indicate the same or corresponding parts.

The molding 1 has almost the same structure as that in FIGS. 1 to 4, but the sheet material 4 provided near the boundary between the foam layer 2 and the non-foam layer 3 is made of aluminum with a thickness of about 0.08 to 0.15 mm. It consists of a gas-impermeable sheet 8 such as foil, and adhesive layers 9 made of vinyl acetate or the like are formed on both sides thereof. Fine grooves 1 are formed on the surface of the sheet material 4 on the foam layer 2 side.
A plurality of grooves 10 are formed in an intersecting manner.
are formed continuously in the longitudinal direction of the molding 1. When such a sheet material 4 is supplied to an extrusion mold and a long material 5 is formed by double extrusion molding of foamed resin and non-foamed resin, the kerf 1
The portion marked 0 remains as a space, and a ventilation path 11 is formed between the foamed layer 2 and the foamed layer 2. This ventilation path 11 is continuous over the entire length of the elongated material 5 and communicates with the outside via a communication path 12 formed between the elongated material 5 and the end cap 6.

Molding 1 configured as above is
The sheet-like material 4 is fed into an extrusion mold, and a long material 5 is formed by double extrusion molding of foamed resin and non-foamed resin. After cutting to a predetermined size, an end cap 6 is formed at the end by injection molding. However, during extrusion molding, a ventilation passage 11 is formed, and the gas that collects near the ventilation passage 11 and the communication passage 1
2 to the outside, deformation such as blistering due to gas collection immediately after molding is prevented.

Furthermore, the molding 1 is used by being attached to a mounting surface such as a car body panel using double-sided adhesive tape or adhesive on the back side, but even when used under extremely hot conditions, the foam layer 2 and non-foam layer 3 Since the gas in the vicinity is discharged to the outside from the ventilation path 11 through the communication path 12, deformation such as blistering due to gas expansion does not occur, and an excellent appearance is maintained. In addition, the strength of the gas-impermeable sheet material 4 is increased, and deformation due to gas expansion in the vicinity is suppressed, so the discharge of the expanded gas from the ventilation path 11 is promoted, and the occurrence of deformation is further reduced. .

FIG. 8 is a perspective view of a portion of a sheet material in another embodiment. In this embodiment, the sheet-like material 4 has an adhesive layer 9 formed on both sides of the sheet 8,
A woven fabric 13 in which fine threads are woven into a mesh or cloth shape is laminated on the surface of the foam layer 2, and when extrusion molding is performed, the fine threads of the woven fabric 13 are interposed between the foam layer 2 and the foam layer 2. to form a ventilation path 11.

FIG. 9 is a cross-sectional view of a sheet-like material in yet another embodiment, in which a plurality of woven fabrics 13 are laminated on one side of the sheet 8, and the air passage 11 formed thereby is large, ensuring reliable exhaust air. As the temperature increases, the strength of the molding 1 also increases.

In the above description, the structure, material, etc. of the sheet-like material 4 are not limited to those in the examples, and the structure, forming means, etc. of the ventilation passage 11 formed on the foam layer 2 side are also limited to those shown in the drawings. However, it can be changed. The shapes, structures, etc. of the molding 1, foam layer 2, non-foam layer 3, end cap 6, etc. are not limited to those shown in the drawings. Further, in the embodiment described above, the ventilation passage 12 is formed between the elongated member 5 and the end cap 6, but it may be provided in other parts. Furthermore, the present invention is applicable not only to side moldings but also to other vehicle moldings having a foam layer.

[Effect of idea]

According to this invention, a sheet-like material is provided near the foamed layer and the non-foamed layer, a ventilation path is formed on the foamed layer side of the sheet-like material, and it is communicated with the outside through a communication path. As the strength increases, the gas inside the foam layer is discharged to the outside, preventing a local increase in gas pressure in the foam layer, and preventing deformation such as blistering on the outer surface of the molding even under extremely hot conditions. and can maintain an excellent appearance.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a molding for a vehicle, Fig. 2 is a sectional view taken along line A-A showing a conventional molding, Fig. 3 is a sectional view taken along line B-B, and Fig. 4 is a perspective view showing a state in which a problem occurs. , FIG. 5 is a perspective view of an embodiment of this invention cut away from the back side, FIG. 6 is a perspective view of the sheet-like material, and FIG. 7 is taken along B-B of FIG. 1.
8 is a perspective view of a sheet material according to another embodiment, and FIG. 9 is a sectional view of a sheet material according to another embodiment. In each figure, the same reference numerals indicate the same or corresponding parts, 1 is the molding, 2 is the foam layer, 3 is the non-foam layer, 4 is the sheet material, 6 is the end cap,
8 is a sheet, 9 is an adhesive layer, 10 is a cut groove, 11 is a ventilation path, 12 is a communication path, and 13 is a woven fabric.

Claims (1)

[Claims for Utility Model Registration] (1) A foamed layer formed inside, a non-foamed layer formed outside to cover this foamed layer, and a foamed layer provided near the boundary between the foamed layer and the non-foamed layer. A foamed layer comprising: a gas-impermeable sheet-like material; a ventilation path formed on the foamed layer side of the sheet-like material; and a communication path that communicates the ventilation path with the outside. Synthetic resin molding with. (2) A synthetic resin molding having a foam layer according to claim 1, wherein the ventilation passages are formed by grooves provided in a sheet-like material. (3) A synthetic resin molding having a foam layer according to claim 1, wherein the ventilation passage is formed by one or more woven fabrics laminated on a sheet-like material. (4) A synthetic resin mold having a foam layer according to any one of claims 1 to 3 of the utility model registration claim, in which the ventilation passage communicates with the outside through a communication path formed at the end of the foam layer. Deing.