JPH05474A - Composite sheet - Google Patents

Abstract

PURPOSE:To provide a composite sheet in which a foamed sheet and a reinforcing or stretching film or sheet are uniformly laminated on each other over the entire surfaces thereof without allowing gas such as air to infiltrate therebetween. CONSTITUTION:The title sheet is formed by sticking an unwoven cloth 2 consisting of 70% of rayon and 30% of polyethylene terephthalate (PET) on a radiation-corsslinked polyethylene foamed sheet 1 and laminating an ethylenic thermoplastic elastomer film 3 thereon by an extrusion laminating process.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite sheet that is used as a ground preventive base material and a waterproof heat insulating material when forming a waterproof layer for a flat roof, for example.

[0002]

2. Description of the Related Art Foamed sheets such as polyethylene crosslinked foamed sheets have various fine characteristics such as having uniform and fine closed cells, excellent heat insulating property, excellent buffering property and withstanding load capacity. It is used for various purposes.

For example, such a polyethylene crosslinked foamed sheet is preferably used as a waterproofing base sheet such as a non-terrain-preventing base material when forming a waterproof layer of a flat roof or a roof heat insulating and waterproof insulating material.

In Japanese Utility Model Publication No. 52-37449, by providing a groove on the lower surface which is continuous to the edge, it is possible to discharge air when adhering to a leveling mortar surface, etc., and ensure the entire surface. A foamed sheet that can be attached has been proposed.

In such a closed-cell foam sheet, in order to more reliably prevent the occurrence of cracks or breaks, a reinforcing resin film or sheet may be bonded to the upper surface thereof, or if cracks or breaks occur. It is possible to attach a film or sheet that is easily stretchable so that water will not leak even if it occurs.

[0006]

By the way, when a reinforcing or stretchable film or sheet is joined and laminated to a closed cell foam sheet, air is often entrapped between the two, though a slight amount. Therefore, air remains between layers in the joined composite sheet, and the entire surface of the sheet is not joined sufficiently, and the part where the air remains becomes blistered, and the function as a waterproof base sheet is fully exerted. There was a problem that was not done.

According to the present invention, in order to solve the above problems, a gas such as air is not caught between the foamed sheet and the reinforcing or stretchable film or sheet, and the both are evenly bonded over the entire surface. The purpose is to provide a composite sheet.

[0008]

The composite sheet of the present invention is characterized in that a closed cell foam sheet and a non-foamed film or sheet are laminated with a continuous porous material layer interposed therebetween.

In the present invention, as the closed-cell foam sheet, for example, a foaming agent-containing polyethylene is extruded into a sheet shape, which is crosslinked by radiation irradiation or a crosslinking agent and then heat-foamed to obtain a foaming ratio of 10 to 40 times. Polyethylene crosslinked foamed sheets of the order of magnitude are preferably used. Also,
In addition to the above-mentioned polyethylene, polypropylene, an olefin-based copolymer such as an ethylene-vinyl acetate copolymer or an ethylene-propylene copolymer, or another thermoplastic polymer may be used as a raw material resin. The side surface of the closed-cell foam sheet opposite to the surface to which the non-foamed film or sheet is joined is described in the above-mentioned Japanese Utility Model Publication No. 52-37449.
It goes without saying that the groove as described in the publication may be provided.

The non-foamed film or sheet is not particularly limited and may be appropriately selected depending on the bondability with the closed-cell foamed sheet and the application. For example, polyethylene, polypropylene, polyvinyl chloride,
Examples thereof include a film or sheet containing a thermoplastic resin such as polyester, nylon or polyurethane as a main component, and a film or sheet containing a thermoplastic elastomer such as an olefin-based thermoplastic elastomer or a urethane-based thermoplastic elastomer as a main component. In particular, when a thermoplastic elastomer film or sheet is used as a base material in the rooftop waterproofing method, even if the closed-cell foam sheet of the main body breaks or cracks, the film or sheet will grow without breaking. It is preferable because it can prevent water leakage.

Examples of the open-pore porous material include porous materials such as polyurethane foam, open-cell foam such as rubber foam, and non-woven fabric. The non-foamed film or sheet is generally attached to the porous material by a heat fusion method, an extrusion lamination method, or the like.

[0012]

In the composite sheet of the present invention, since the non-foamed film or sheet is laminated on the closed-cell foam sheet through the continuous porous material layer,
The air entrapped during lamination is diffused from the pores of the porous material, air remains at the joints, and the entire surface is joined.

[0013]

Embodiments of the composite sheet of the present invention will be described below with reference to the embodiments of the drawings. FIG. 1 is a cross-sectional view of a composite sheet when a nonwoven fabric is used as a porous material, and FIG. 2 is a cross-sectional view of a composite sheet using an open-cell foam sheet as a porous material.

The composite sheet shown in FIG. 1 is suitable as a base material for preventing unevenness especially in a rooftop waterproofing method.
This composite sheet has a thickness of 3 as a closed cell foam sheet.
mm, and a foaming ratio of 20 times, a radiation-crosslinked polyethylene foam sheet 1 is used.
A non-woven fabric 2 having a basis weight of 90 g / m ² consisting of 0% and 30% polyethylene terephthalate (PET) is attached, and 0.3 mm of an ethylene-based thermoplastic elastomer (T
PO # 8032, manufactured by Mitsui Petrochemical Industry Co., Ltd.) is laminated by an extrusion lamination method.

In this embodiment, the foamed sheet 1 is provided with grooves 11, 11 ... Continuing to the edge on the lower surface thereof, so that gas such as air is not entrained in the surface to be adhered such as leveling mortar. It is supposed to be attached.

FIG. 2 shows a composite sheet used as a waterproof heat insulating material in a waterproof method, for example. This composite sheet has a thickness of 3 m as a closed-cell foam sheet.
m, a radiation-crosslinked polyethylene foam sheet 1a having a foaming ratio of 20 times is used, and a specific gravity of 0.0 on the foam sheet 1.
3. A polyurethane foam sheet, which is an open-cell foam having a thickness of 1 mm, is adhered, and 0.3 mm of an ethylene-based thermoplastic elastomer (TPO # 8032, manufactured by Mitsui Petrochemical Industry Co., Ltd.) is applied by an extrusion lamination method. It is formed by stacking.

The above two composite sheets did not show any air entrapment in appearance, and when they were heated in a constant temperature bath at 70 ° C. for 1 hour, so-called blistering did not occur. On the other hand, the composite sheet obtained by directly adhering the ethylene-based thermoplastic elastomer 3 to the foam sheets 1 and 1a without interposing the non-woven fabric 2 and the open-cell foam sheet 2a has air entrapped therein, and a constant temperature bath at 70 ° C. When heated for 1 hour, the swelling phenomenon appeared remarkably.

[0018]

INDUSTRIAL APPLICABILITY As described above, the composite sheet of the present invention is one in which air does not remain at the joint portion of the laminated surface and is uniformly joined over the entire surface, the joint portion does not swell, and the waterproof sheet. The function as a base material or a heat insulating sheet is sufficiently exhibited.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a composite sheet of the present invention.

FIG. 2 is a sectional view of another embodiment of the present invention.

[Explanation of symbols]

 1, 1a Closed-cell foam sheet 2, 2a Open-cell porous material 3 Non-foaming film

Claims (1)

Claim: What is claimed is: 1. A composite sheet comprising a closed cell foam sheet and a non-foamed film or sheet, which are laminated via a porous layer having continuous pores.