JPH06316020A - Waterproof sheet - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an improved waterproof sheet for use in a waterproofing method applied to the roof of a concrete building, for example. A rubber sheet and a chemically crosslinked polyolefin resin foam sheet are heat-sealed together via a non-crosslinked thermoplastic resin film containing no crosslinking agent. [Effect] At the time of waterproof construction, the rubber sheet of the waterproof sheet can be exposed by peeling off the foam sheet of the required portion without leaving the foam pieces remaining due to material destruction, and after the waterproof construction, the foam sheet can be exposed. The adhesion between the sheet and the rubber sheet is maintained and the waterproof function can be maintained for a long time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved waterproof sheet used in a sheet waterproofing method for waterproofing, insulating and protecting from impacts on rooftop concrete of buildings and the like. .

[0002]

2. Description of the Related Art A sheet waterproofing method is a method of waterproofing and insulating a building by attaching a rubber sheet to the roof of a concrete building with an adhesive. To explain this construction method in detail, first, as shown in FIG.
About 200 g / m ² of chloroprene-based primer is applied to the concrete base 1 on the roof of the building and dried. Next, a polyethylene resin foam sheet 2 having a thickness of about 10 mm and a foaming degree of about 20 to 30 is adhered to this using a chloroprene adhesive of about 150 g / m ² , and a joint-attaching rubber tape 3 is applied to a joint. wear. Then, apply a chloroprene adhesive on top of this with a roll brush.
The rubber sheet 4 having a thickness of about 2 mm is attached after applying about 00 g / m ^{2 and} allowing sufficient open time.

In this conventional sheet waterproofing method, as described above, a primer is applied to the concrete foundation 1 on the roof of the building and dried, then an adhesive is applied and the polyethylene resin foam sheet 2 is attached, and thereafter, The work was complicated when an adhesive was applied on the polyethylene resin foam sheet 2 that was pasted and the rubber sheet 4 was pasted. For this reason, in recent years, a waterproof sheet in which a rubber sheet 4 and a polyethylene resin foam sheet 2 are integrally heat-bonded to each other is previously made in a factory, and this is brought to a construction site and is bonded to one surface of a concrete base. The method has become popular.

By the way, in this construction method, the waterproof sheet used is a rubber sheet 4 and a polyethylene resin foam sheet 2 which are previously heat-bonded integrally at a factory. When it is attached to the base 1, at a place where there is a construction site, a part 2A of the polyethylene resin foam sheet 2 constituting the waterproof sheet is peeled off to expose the rubber sheet, and the exposed rubber sheet 4B (see FIG. 3). Put the parts together. Alternatively, it is necessary to peel off a part of the polyethylene resin foam sheet 2 and attach the exposed end 4B of the rubber sheet to the concrete wall 5.
(See FIG. 4) When the need arises for such work, when the part 2A of the polyethylene resin foam sheet 2 is peeled off from the conventional waterproof sheet, polyethylene is formed on the exposed surface of the rubber sheet 4B that is peeled and exposed. When the resin foam sheet piece remains, when it is attached to the concrete wall 5,
Since a gap will be generated in the pasted portion, a material that does not have such a problem is required.

With respect to such requirements, a waterproof sheet obtained by laminating a rubber sheet with a polyethylene resin foam sheet (hereinafter referred to as electron beam crosslinked polyethylene foam sheet) crosslinked and foamed by electron beam irradiation is a chemical crosslinking agent. Polyethylene resin foam sheet that has been crosslinked and foamed by using (hereinafter referred to as chemically crosslinked polyethylene foam sheet)
Since the amount of the polyethylene resin foam sheet debris adhered to the rubber sheet surface is smaller when the polyethylene resin foam sheet is peeled off than the waterproof sheet obtained by bonding the above-mentioned waterproof sheet, the above-mentioned waterproof sheet is preferably used. Although the exact reason why the adhesion amount is small in the former waterproof sheet is not known, the chemically cross-linked polyethylene foam sheet has a lower melting point because the degree of cross-linking on the foam sheet surface is lower than that of the electron beam cross-linked polyethylene foam sheet. The reason is considered to be that the adhesive strength at the time of heat bonding with the rubber sheet becomes stronger, the material destruction of the foam sheet occurs at the time of peeling, and the debris remains attached to the rubber sheet.

[0006] However, in the sheet waterproof portion constructed by using a waterproof sheet obtained by laminating this electron beam crosslinked polyethylene foam sheet on a rubber sheet, the rubber sheet and the polyethylene foam sheet are easily separated from each other by some impact after construction. Peels off. This tendency is even more pronounced under hot weather in summer. In this way, when a part where the rubber sheet and the polyethylene foam sheet are separated occurs in the waterproof part of the sheet,
Rainwater will start to infiltrate from this part, which will result in cracking of the concrete and impair the function of the waterproof sheet.

[0007]

In the present invention, as a result of intensive investigations focusing on such points, the adhesive force between the rubber sheet and the polyethylene foam sheet is better than that using the electron beam crosslinked polyethylene foam sheet. It is possible to develop a waterproof sheet that does not remain in the rubber sheet due to material destruction of the polyethylene foam sheet when the polyethylene foam sheet is peeled from the rubber sheet. That is, in the waterproof sheet of the present invention, as shown in FIG. 1, the rubber sheet 4 and the chemically crosslinked polyolefin foam sheet 7 are heat-sealed via a non-crosslinked thermoplastic resin film 6 containing no crosslinking agent. It is characterized by.

The waterproof sheet of the present invention is preferably manufactured by any of the following methods. In the first method, a mixture is prepared by mixing a polyolefin resin such as polyethylene resin with a thermal decomposition type chemical foaming agent such as azodicarbonamide and a chemical crosslinking agent such as dicumyl peroxide. Next, the above mixture is extruded into a sheet to form a foam mother board sheet, and one surface of the foam mother board sheet is, for example, a non-crosslinked non-crosslinked agent such as a high-pressure polyethylene resin film. A thermoplastic resin film (hereinafter referred to as a non-crosslinked thermoplastic resin film) is laminated. This laminate is heated and blown with hot air in a heating furnace having a wire mesh conveyor, for example, to produce a chemically crosslinked polyolefin resin foam sheet having a non-crosslinked thermoplastic resin film laminated on one side. Next, the non-crosslinked thermoplastic resin film laminated on one surface produced as described above of the non-crosslinked thermoplastic resin film surface of the chemically crosslinked polyolefin resin foam sheet and the surface of the rubber sheet, with an infrared heater or the like. Heated well,
This is a method of heat-bonding integrally by pressurizing this with a roll.

Another method is a mixture of a polyolefin resin such as polyethylene resin, a thermal decomposition type chemical foaming agent such as azodicarbonamide and a chemical crosslinking agent such as dicumyl peroxide. create. This mixture is extruded into a sheet to form a foam base plate sheet, and the foam base plate sheet is heated by hot air in a heating furnace having, for example, a wire mesh conveyor to be foamed to form a chemically crosslinked polyolefin resin foam. Make a sheet. Next, on one side of the chemically crosslinked polyolefin resin foam sheet, for example, a non-crosslinked thermoplastic resin film such as a high-pressure polyethylene resin film is heated with an infrared heater or the like and then laminated, and the non-crosslinked thermoplastic resin on one side. Make a chemically crosslinked polyolefin resin foam sheet laminated with the film. Next, the surface of the non-crosslinked thermoplastic resin film and the surface of the rubber sheet of the chemically crosslinked polyolefin resin foam sheet in which the non-crosslinked thermoplastic resin film is laminated on one side manufactured as described above are sufficiently heated with an infrared heater or the like. It is a method of heating and pressurizing this with a roll to integrally heat-bond.

[0010]

The waterproof sheet of the present invention is a chemically crosslinked polyolefin foam sheet laminated with a non-crosslinked thermoplastic resin film, and the rubber sheet is heat-sealed on the non-crosslinked thermoplastic resin film surface. The non-crosslinked thermoplastic resin film in the waterproof sheet of the present invention has a low melting point because it is a non-crosslinked material, and due to factors such as the difference in the surface state, the adhesive force with the rubber sheet is not different from that of the chemically crosslinked polyolefin foam sheet. It is far superior to the adhesive strength. Therefore, in the waterproof sheet of the finished product, the adhesive force of the rubber sheet to the non-crosslinked thermoplastic resin film is larger than the adhesive force of the chemically crosslinked polyolefin foam sheet to the film, causing the material destruction of the chemically crosslinked polyolefin foam sheet. The foam sheet can be peeled off without leaving, that is, without leaving debris deposits on the foam sheet.

[0011]

【Example】

Example 1 15 parts by weight of azodicarbonamide and 1 part by weight of dicumyl peroxide were mixed with 100 parts by weight of a high-pressure polyethylene resin and mixed uniformly, and the mixture was extruded with a width of 350 mm and a thickness of 350 mm. A 1.4 mm foam mother sheet was produced. Next, a 0.3 mm thick high-pressure polyethylene resin film was laminated on the upper and lower surfaces of the foam mother sheet by heat, and the laminated product was placed on a wire mesh conveyor and heated in a heating furnace at 220 ° C. Was sent for 5 minutes to heat and foam. As a result, width 1000 mm, thickness 6
An extremely good double-sided laminated chemically crosslinked polyethylene foam sheet having a thickness of mm and a density of 0.03 g / cc was obtained.
One side of this double-sided laminated chemically crosslinked polyethylene foam sheet and the surface of the polychloroprene rubber sheet are sufficiently heated by an infrared heater, and both heating surfaces are pressed against each other with a roll to fuse them to form a waterproof sheet. Obtained.
In the obtained waterproof sheet, the polyethylene resin film layer was firmly fused with the chemically crosslinked polyethylene foam sheet and the polychloroprene rubber sheet. When the chemically crosslinked polyethylene foam sheet was peeled off from the obtained waterproof sheet, only the foam sheet was peeled off, and the high-pressure polyethylene resin film remained fused to the polychloroprene rubber sheet surface.

Example 2 15 parts by weight of azodicarbonamide and 1 part by weight of dicumyl peroxide were mixed with 100 parts by weight of a high-pressure polyethylene resin, and the mixture was uniformly mixed. , A 1.4 mm thick foam base sheet was produced. This foam mother board sheet was placed on a wire mesh conveyor and heated at 220 ° C. for 5 minutes in a heating furnace to heat and foam. As a result, width 1000 mm, thickness 6 m
A very good chemically crosslinked polyethylene foam sheet having m and a density of 0.03 g / cc was obtained. Next, one side of this chemically crosslinked polyethylene foam sheet has a thickness of 0.3 mm.
The high-pressure polyethylene resin film was heated with an infrared heater and then laminated. After that, the film surface of the obtained one-side laminated chemically crosslinked polyethylene foam sheet and the surface of the polychloroprene rubber sheet were sufficiently heated by an infrared heater, and both heating surfaces were pressed together by a roll to fuse them. To obtain a waterproof sheet. In the obtained waterproof sheet, the polyethylene resin film layer was firmly fused with the chemically crosslinked polyethylene foam sheet and the polychloroprene rubber sheet. When the chemically crosslinked polyethylene foam sheet was peeled off from the obtained waterproof sheet, only the foam sheet was peeled off, and the high-pressure polyethylene resin film remained fused to the polychloroprene rubber sheet surface.

Comparative Example 1 In the same manner as in Example 2, width 1000 mm, thickness 6 mm,
A very good chemically crosslinked polyethylene foam sheet with a density of 0.03 g / cc was produced. One side of this chemically crosslinked polyethylene foam sheet and the surface of the same polychloroprene rubber sheet as used in Example 1 were sufficiently heated by an infrared heater, and both heating surfaces were pressed against each other with a roll and fused. To obtain a waterproof sheet. In the obtained waterproof sheet, the chemically crosslinked polyethylene foam sheet and the polychloroprene rubber sheet were directly and firmly fused. When the chemically crosslinked polyethylene foam sheet was peeled off from the obtained waterproof sheet in the same manner as in Example 1, the foam sheet caused material destruction on the surface of the polychloroprene rubber sheet, and the fractured pieces of the foam were polychloroprene. A large amount adhered and remained on the surface of the rubber sheet.

COMPARATIVE EXAMPLE 2 15 parts by weight of azodicarbonamide and 1 part by weight of dicumyl peroxide were mixed with 100 parts by weight of high-pressure polyethylene and mixed evenly. , A 1.4 mm thick foam base sheet was produced. This foam mother board sheet was cross-linked by irradiating it with an electron beam by an electron beam irradiator, and then this foam mother board sheet was placed on a wire mesh conveyor and placed in a heating furnace.
Hot air at 0 ° C. was sent for 5 minutes to heat and foam. As a result, the width is 1000 mm, the thickness is 6 mm, and the density is 0.03 g /
An electron beam crosslinked polyethylene foam sheet having a very good cc was obtained. After that, one side of the obtained electron beam crosslinked polyethylene foam sheet and the surface of the polychloroprene rubber sheet were sufficiently heated by an infrared heater, and both heating surfaces were pressed together by a roll to fuse them. I got a tarpaulin. In the obtained waterproof sheet, the electron beam crosslinked polyethylene foam sheet and the polychloroprene rubber sheet were directly fused. When the electron beam crosslinked polyethylene foam sheet was peeled off from the obtained waterproof sheet,
The foam sheet could be peeled off more easily than in the case of the product of the present invention.

[0015]

According to the waterproof sheet of the present invention, at the time of waterproofing, the foam sheet at a required portion can be uniformly peeled off, that is, the foam sheet can be peeled off without leaving residual adhesion of the foam piece due to material destruction of the foam sheet. The rubber surface of the waterproof sheet can be exposed, and after waterproofing, the adhesion between the foam sheet and the rubber sheet can be maintained and the waterproof function can be maintained for a long time.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a waterproof sheet of the present invention.

FIG. 2 is an explanatory view of a sheet waterproofing method.

FIG. 3 is an explanatory view when a part of the polyethylene resin foam sheet of the waterproof sheet is peeled off.

FIG. 4 is an explanatory view showing how a part of the polyethylene resin foam sheet of the waterproof sheet is peeled off and the exposed rubber sheet portion is attached to a concrete wall.

[Explanation of symbols]

 1 ... Concrete substrate 2 ... Polyethylene resin foam sheet 2A ... Part where polyethylene resin foam sheet is peeled off 3 ... Joint-attached rubber tape 4 ... Rubber sheet 4B ... Part where rubber sheet is exposed 5 ... Concrete wall 6 ... Thermoplastic resin film 7 ... Chemically cross-linked polyolefin foam sheet

Claims (1)

[Claims] 1. A waterproof sheet, characterized in that a rubber sheet and a chemically crosslinked polyolefin resin foam sheet are heat-sealed via a non-crosslinked thermoplastic resin film containing no crosslinking agent.