JPH01150534A - Water-proof sheet - Google Patents

Abstract

PURPOSE:To obtain a water-proof sheet which is free from partial relief even during the use at high temperatures, by providing a foaming sheet layer at one surface of a vulcanized rubber sheet having weather resisting property, which sheet layer contains continuous cells and is provided with net-patterned grooves therein. CONSTITUTION:There is formed a foaming sheet layer 2 at one surface of a vulcanized rubber sheet 1 having resistance against the weather. The foaming sheet layer 2 contains continuous cells, and moreover it is provided with net-patterned grooves 3. The foaming sheet layer 2 at the lower side and adhered to a foundation may be formed of vulcanized rubber foaming material having resistance against the weather or a high-molecular foaming material. In this case, it is particularly desirable to use the same rubber as that of the vulcanized rubber sheet at the upper side from the viewpoints of the manufacturing process and strength. In other words, when the water- proof layer 1 and the foaming sheet layer 2 are made of the same material, it is convenient in that the water-proof layer 1 and the lower sheet 2 containing the foaming agent can be laminated while they are raw, and then moved into the vulcanizing process where they are integrally vulcanized and molded. The grooves 3 in the foaming sheet layer 2 which are in the form of a lattice, honeycomb or rhombus, etc. are continuously communicated to each other.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rubber waterproof sheet used for the roof of a building, the bottom of a water reservoir, or the like.

[Prior Art] Conventionally, when waterproofing the roof of a building or a water tank, etc., a construction method has been used in which a waterproof sheet is attached to a subsurface such as concrete with an adhesive.

In this case, the solvent contained in the adhesive or the moisture contained in the concrete slab evaporates, and since there is no place for this solvent gas to escape, it not only reduces the waterproof function due to blistering and peeling of the adhesive, but also damages the appearance. This has become a big problem.

This swelling caused by solvent gas can be caused by solvent gas and water vapor from the adhesive generated between the concrete base and the back of the tarpaulin sheet, or if the waterproof sheet has a multilayer structure, by solvent gas from the adhesive between each layer. There is.

On the other hand, the adhesive between the tarpaulin sheet and the substrate uses a pressure-sensitive adhesive, which is dried and then applied with pressure to prevent blistering caused by solvent gas between the waterproof sheet and the substrate. To deal with the solvent gas generated between each layer of a waterproof sheet, there is a method of sandwiching a mesh sheet to allow the gas to escape (Japanese Patent Laid-Open No. 58-541).
No. 51) has been proposed.

However, in the case of waterproof sheets installed on roofs, etc., the cause of the sheet's blistering is not only the adhesive solvent, but also water vapor that accumulates in cracks in the concrete that inevitably occur over a long period of time. The above-mentioned conventional methods are ineffective against lifting of the tarpaulin sheet due to such causes.

In other words, when exposed to direct sunlight, the temperature of the concrete surface often exceeds 100°C, and at this time, the water in the concrete cracks evaporates, and like with solvents, gas with no escape causes the blistering. This causes the tarpaulin sheet to partially lift up.

In response to this, a method was developed in which an open-cell foam sheet was provided on one side of a rubber tarpaulin sheet, and this foam sheet surface was attached to a roof etc. with adhesive to be used as a tarpaulin sheet, but the degassing performance was is still insufficient, and more effective solutions are desired.

[Problems to be Solved by the Invention] The object of the present invention is to provide a waterproof sheet with a simple structure that does not partially lift even when used on a roof or other high temperature environment. be.

[Means for Solving the Problems] The present inventors investigated in detail the method of using the open-cell foam sheet, and found that even though the cells in the foam sheet are composed of open cells, the base of the foam sheet It has been discovered that a thin film is formed on the surface of the bubbles in contact with the surface during molding, and this effectively seals the base.

However, this film on the surface of the foam also has the function of widening the adhesive area with the base and firmly adhering and fixing it to the base, and if this film is destroyed, the adhesive strength with the base will decrease.

In order to eliminate the sealed state of the base layer caused by the cell membrane on the back side without reducing adhesive strength and to provide deaeration performance, the present inventors created a net-like groove to aid ventilation in combination with the open cell structure. It has been discovered that by providing the foam sheet on the surface, the above problems can be solved without impairing the performance as a waterproof sheet, especially without reducing the adhesive area with the base, and without reducing waterproof performance, and the present invention. completed.

That is, the present invention provides a foamed sheet layer on one side of a weather-resistant vulcanized rubber sheet, the foamed sheet layer has open cells,
The waterproof sheet is characterized in that the foam sheet layer is provided with net-like grooves.

As the weather-resistant vulcanized rubber used for the waterproof layer of the waterproof sheet of the present invention, for example, a vulcanized sheet of a rubber with high aging resistance such as EPDM, IIR, chlorosulfonated polyethylene, or chlorobrene can be used.

The waterproof layer of the present invention may have any thickness as desired, but is usually 0.5 to 2.5 mm.

The lower foam degassing layer that adheres to the base of the present invention can be made of weather-resistant vulcanized rubber foam or foamed polymer material. In this case, it is particularly desirable to use the same rubber as the weather-resistant vulcanized rubber sheet on the top surface, both from the viewpoint of the manufacturing process and from the viewpoint of strength.

That is, when the waterproof layer and the foam degassing layer of the waterproof sheet of the present invention are made of the same material, the waterproof layer and the foaming agent-containing bottom sheet are laminated in the state of raw rubber and then put into a vulcanization process and vulcanized as one unit. It is convenient because it can be sulfur molded.

This foamed sheet layer consists of open cells with a foaming ratio of 150 to 300%, preferably 200 to 250%, and the degree of cell continuity is about 40 to 80%.

In the present invention, the degree of continuity of the bubbles is expressed in units of 1010×1
The ratio of the amount of permeated water to the amount of water used per 0 was fixed.

Although the foam layer of the waterproof sheet of the present invention can have any thickness as desired, a foam layer of 1 to 3 mm is usually used.

A mesh-like groove is provided in the foam layer of the waterproof sheet of the present invention. This net-like shape can be used in any pattern as long as the valleys and grooves are continuous.For example,
A lattice shape, honeycomb shape, rhombus shape, etc. can be adopted.

The spacing between the meshes of the foamed sheet layer of the present invention is not particularly limited, but can be set to 5 to 30 mm. Even if the spacing is less than 5 mm, the degassing effect will not be improved, and if the spacing exceeds 30 mm, the gas degassing performance will deteriorate and, in some cases, bulges will occur.

The grooves of the foam sheet layer of the present invention have a depth of 0.1 to 1 mm.

It is possible to provide one having a width of about 0.3 to 1 mm.

Such grooves can be easily formed, for example, by placing glass cloth or polyester liner cloth on the surface of the foam layer, forming a sheet together with the foam layer, and then peeling off the cloth from the foam layer after vulcanization. can do.

When forming grooves using this method, the width and depth of the grooves are
Both have the same fiber diameter.

The grooves provided in the foam sheet of the present invention can be forcibly peeled off after being molded using the method described above, as this will destroy the membrane on top of the foam bubbles in contact with the grooves. This is desirable because the air bubbles are released and the degassing performance as open cells becomes better.

[Example] The present invention will be explained in more detail with reference to Examples.

Examples: A waterproof layer sheet molded from an EPDM compound having the composition for a waterproof layer shown in Table 1, and two foamed degassing layer compositions using EPDM rubber and IIR rubber shown in Table 1. A deaeration layer sheet was molded.

In the waterproof layer sheet of the EPDM compound obtained in this way,
A foam degassing layer made of an EPDM rubber compound and a liner cloth made of polyester were laminated, heat-pressed, and integrally vulcanized to obtain a waterproof sheet.

Similarly, a foam degassing layer sheet made of 11R compound and a polyester liner cloth are laminated on a waterproof layer sheet made of EPDM compound, and the cloth is vulcanized by heat-pressing and then peeled off after molding. Got a tarpaulin.

The waterproof sheet of this example has a structure as shown in the explanatory perspective view of FIG. The widths of the layers are both 1200 mm, and as shown in the figure, the waterproof layer and the foam degassing layer are formed so as to be laterally shifted from each other by 100 mm. By bonding these misaligned portions with an adhesive, two or more waterproof sheets can be joined without any difference in level or deterioration of waterproof performance.

The length of the tarpaulin sheet can be manufactured to any desired length depending on the use and distribution form.

Such waterproof sheets were manufactured using various polyester liner cloths with different mesh groove widths, depths, and mesh spacings, and their degassing performance was tested.

Separately, as a comparative example, a waterproof sheet having the same shape and a foam degassing layer without only mesh grooves was manufactured and its degassing performance was tested.

The degassing performance of the example of the present invention is J1. SK63
It was measured by measuring the heating loss based on 2g and using this as a measure of degassing performance.

That is, as shown in Fig. 2, the inner diameter is 40 mm and the depth is 25 mm.
mm cylindrical container A with an outer diameter of 601111 mm on the top surface.
11% In a container having 7 rungs B with an inner diameter of 40 mm,
Pour 30 mQ of water at a temperature of 80°C, and add an outer diameter of 60 m to this.
A disk-shaped test tarpaulin sheet of m was manufactured as described above; cut it from the tarpaulin sheet, paste it with adhesive on the entire surface of the 7 rungs of the container, and keep the container at a temperature of 80 ° C.
The weight was kept constant and the relationship between the passage of time and the total weight loss of the container was measured.

The results are shown in Tables 2 and 3.

(Margin below) Table 2 Table 3 Note: The numbers in the table are the same as in Table 2.

Table 2 shows the case where the foam degassing layer is EPDM vulcanized rubber and II
For each case of R vulcanized rubber, the relationship between time and weight loss is shown when grooves in a lattice-like mesh with an interval of 10 mm are provided in the foam degassing layer, and the width and depth of the grooves are 0.5 mm and 1 mm. It is something that

Table 3 also shows the results of measuring the influence of the mesh spacing when the groove width and depth were set to 0.2 mm and 0.4 mm for the case where the deaeration layer was EPDM and IIR.

From these results, it can be seen that the foamed deaeration layer having the mesh grooves of this example has a high deaeration performance.

It was also found that the larger the groove width and depth, the greater the deaeration performance, and the narrower the mesh spacing, the greater the deaeration performance.

Practical test A Blistering test An EPDM rubber layer with the same composition as in the example and measuring 1 m in length and width was used as a waterproof layer, and this was divided into four quarters as shown in Figure 3, and the upper left part was filled with EPDM rubber having closed cells. foam layer,
The lower right part is an EPDM foam layer with open cells, and the upper right and lower left parts are EPDM continuous EPDM foam layers with grooves of width and depth of 0, 5 mm, and 1.0 mm, respectively, which were used in Table 2 of Examples. A product made of laminated foam layers.

A hole with a diameter of 40 mm was made in the center of this test sheet, and cotton soaked in 309 water was placed in the center of each of the four sections on a 1 m square slate board of the same size as this sheet. The above test sheet was attached using an adhesive.

As shown in the cross-sectional view of FIG. 4, the periphery of the laminated slate plate 8 and test sheet was completely sealed with sealing tape 9 to prevent air from escaping from the periphery. That is, in this test laminate, the only escape port for degassed gas from the back surface of the test sheet was the central hole 6.

i) Heating test The test laminate prepared above was heated to a waterproof rubber surface temperature of 7.
When heated to 5°C, blistering occurred in the center of the upper left and lower right parts.

No swelling was observed in the lower left and upper right parts.

(2) Decompression test The surface temperature of the same test specimen as above was maintained at 44°C, a decompression cover was brought into close contact with the surface, and the pressure was reduced to 850 mm of water column.

The adhesive started peeling off in the upper left and lower right parts after 10 minutes. There was no abnormality in the upper right and lower left parts of the waterproof sheet of the present invention.

Adhesive strength tests were conducted on the two types of waterproof sheets of the foam degassing layer EPDM of the present invention used in Table 2 of Adhesion Test Examples and the non-grooved waterproof sheet of Comparative Example. That is, a test piece was adhered to a concrete surface using a chloroprene adhesive, and after being left at room temperature, the adhesive strength in the direction perpendicular to the adhesive surface was measured using a Schopper type tensile tester.

For both grooved and non-grooved adhesive strength,
A value of 2.5 kg/inch was obtained, and no decrease in adhesive strength was observed even with the grooves.

[Effects of the Invention] The waterproof sheet of the present invention does not swell due to solvent gas in the adhesive after construction, and can also prevent bulges caused by water accumulated in cracks in concrete, so that adhesiveness is improved. It has the advantage that it can be firmly fixed forever, extending the service life of the tarpaulin sheet, and can be used without damaging the appearance, which is becoming more important these days.

Furthermore, the contact area between the waterproof sheet and the base remains almost the same, the adhesive strength with the base does not decrease, and blistering can be prevented regardless of the degree of drying of the adhesive solvent or the type of adhesive. There are advantages such as being able to

As a result, it has the advantage of being suitable for waterproofing construction on roofs and rooftops where the temperature rises and where appearance is important, and can be widely used as a useful waterproof sheet. .

[Brief explanation of the drawing]

FIG. 1 is a perspective explanatory view of a waterproof sheet according to an embodiment of the present invention, FIG. 2 is a sectional view showing a test method for testing the degassing performance of the waterproof sheet, and FIG. 3 is a cross-sectional view of the waterproof sheet. FIG.
The figure is a sectional view thereof. The symbols in the figure are: 1: waterproof layer, 2: foam degassing layer, 3: deaeration groove, 4: adhesive allowance for joining, 5: adhesive receiver for joining, 6: ventilation hole, 7: hydrated cotton, 8; Slate board, 9; Sealing tape,
A: metal container, B: flange, C: water phase. Patent applicant: Toyo Rubber Industries, Ltd. Agent: Mitsuru Uchiyama Figure 1 Figure 2

Claims (1)

[Claims] 1. A waterproof sheet, characterized in that a foam sheet layer is provided on one side of a weather-resistant vulcanized rubber sheet, the foam sheet layer has open cells, and a net-like groove is provided in the foam sheet layer.