JPH11221878A - Double-layer waterproof sheet for outdoor laying - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a double-layer waterproof sheet for outdoor laying good in mutual bonding properties at the time of execution, excellent in weatherability, mechanical characteristics, crack resistance or the like, not lowering its durability even in outdoor use over a long period of time and reduced in its interlaminar peel phenomenon. SOLUTION: A water-proof sheet 3a made of a soft synthetic resin used as a flat roofing material or the like has a double-layer structure wherein a surface layer 2 is provided on the single surface or both surfaces of a base layer 1 and both of the base layer 1 and the surface layer 2 are brought to a double-layer state while the compounded raw materials of the respective layers become a mutually heated and melted state before reaching the lip of a T-die in a coextrusion molding method. By this constitution, high durability and waterproof function can be held.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-layer waterproof sheet for outdoor laying comprising a base layer and a surface layer, which is used as a roofing material for a flat roof or the like.

[0002]

2. Description of the Related Art Conventionally, asphalt-based roofing materials, synthetic polymer-based roofing materials, and the like have been used for waterproofing general buildings and civil engineering structures.

[0003] Asphalt roofing materials have occupied the mainstream of waterproofing work for many years.
Because it is a hot construction method involving fire, there are many problems such as odor and fire safety work environment problems and many man-hours, difficult work on steep slopes, large changes in physical properties due to changes in outside air temperature, etc. In order to improve these problems, synthetic polymer roofing materials are being used frequently.

Since roofing materials are mainly used outdoors, they have good weather resistance and heat resistance, and have small expansion and contraction in a wide temperature range from low to high temperatures. It is required to be flexible and have mechanical strength and elongation properties. This is not an exception in a synthetic polymer roofing material (hereinafter referred to as a waterproof sheet). And when attaching a waterproof sheet, the joining property between waterproof sheets is also required.

In most cases, a single sheet of a thermoplastic resin is used as a waterproof sheet. This is, in addition to the thermoplastic resin which is the main component of the raw material components constituting the sheet, a plasticizer, a stabilizer, a lubricant,
Various other raw material components such as an ultraviolet absorber, an antioxidant, a colorant, and a filler are selected according to the purpose, and are mixed in a state of being evenly mixed in the thickness direction of the waterproof sheet. . From the point of ease of laying construction and economical points,
In particular, those having a single-layer structure made of polyvinyl chloride resin are often used. Recently, for the purpose of imparting durability, lamination by coating an acrylic resin film or the like on the surface of a single-layer flexible polyvinyl chloride resin sheet manufactured by a calendering method or an extrusion method, or waterproofing. There is a sheet obtained by laminating a thermoplastic resin sheet in which an ultraviolet absorber or an ultraviolet shielding agent is uniformly dispersed and mixed on the surface of the sheet by a lamination method.

[0006] In some cases, a composite sheet is used in which a net-like woven fabric or nonwoven fabric made of polyester synthetic fiber, glass fiber, or the like is sandwiched between two layers of thermoplastic resin and integrated. ing.

[0007] Composite and lamination of the waterproof sheet as described above is very important for improving the durability of the waterproof sheet itself against deterioration in physical properties due to sunlight, rainwater, changes in the outside air temperature, and deterioration due to cracks and the like. Which is a frequently applied convention.

In this type of waterproof sheet, the workability in the initial stage of construction, the elasticity due to changes in the outside temperature, the waterproof function, and the like often depend on the internal mechanical or physical properties that occupy most of the sheet. Environmental changes over time, especially sunlight,
Material deterioration phenomena due to aging such as rainwater, changes in outside temperature, etc., are often adopted from the viewpoint that the mechanical or physical properties of the sheet surface are changed. Taking an example of the composition of the agent, the UV absorber is uniformly mixed in the thickness direction of the sheet similarly to the plasticizer, and over time, the UV absorber on the surface portion is consumed, Although the UV absorber inside the sheet contributes to the prevention of deterioration due to light, most of the UV absorber inside the sheet remains without contributing to the deterioration prevention, and as a result, the expensive UV absorber This is extremely wasteful and extremely disadvantageous in terms of cost.

However, in either case of the above-mentioned complexing or laminating, disadvantages such as an increase in the number of materials to be handled and the number of steps and an increase in manufacturing cost are caused. Due to the low durability of the lamination strength at the interface, there is a problem that peeling occurs over time and the purpose of improving durability cannot be achieved.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the conventional waterproof sheet. The present invention has a multi-layer structure, and has good mutual bonding properties during construction. There is a multi-layer waterproof sheet for outdoor laying that has excellent weather resistance, mechanical properties, crack resistance, etc., and does not decrease its durability even for long-term outdoor use, especially with little interfacial delamination phenomenon. It is intended to provide.

[0011]

In order to achieve the above object, the present invention relates to a synthetic resin waterproof sheet used as a roofing material or the like, which has a multi-layer structure having a surface layer on one or both sides of a base layer. The above-mentioned surface layer is a multilayer waterproofing for outdoor laying, characterized in that, in the co-extrusion molding method, the compounding raw materials of the respective layers are made into a multilayer state under a heated and melted state before reaching the lip of the T-die. Make the sheet a gist.

In a preferred embodiment of the present invention, the base layer of the multilayer waterproof sheet for outdoor laying is made of a soft polyvinyl chloride resin, and the surface layer is made of a soft synthetic resin of the same kind as the base layer, or is compatible with the base layer. The multilayer waterproof sheet for outdoor laying according to claim 1, comprising a different kind of soft synthetic resin.

In the present invention, the synthetic resin used for the base layer of the multilayer waterproof sheet for outdoor laying is a soft thermoplastic resin having a degree of flexibility that does not impair the workability at the time of laying. Vinyl resin, chlorinated polyethylene resin, copolymer of ethylene or propylene with other α-olefin, or ethylene and vinyl acetate,
Copolymers with methacrylic acid, methacrylic acid esters and the like can be mentioned, and these can be used alone or as a mixture.
In particular, flexible polyvinyl chloride resin is excellent in flame retardancy, manufacturing processability, workability, etc., and is also advantageous in terms of cost,
It is suitably used as a base layer of a multilayer waterproof sheet for outdoor laying.

In this case, the polyvinyl chloride resin as the base layer is not particularly limited to a kind thereof, but may be a homopolymer of the vinyl chloride resin or a copolymer of the vinyl chloride resin and vinyl acetate, ethylene, propylene or the like. Alternatively, they can be used as a mixture of two or more.

The polyvinyl chloride resin as the base layer may be a plasticizer such as polyester, phthalate, adipic ester, trimellitate, pyromellitic ester or phosphate ester plasticizer. Agents are applicable.

Further, in addition to the above-mentioned plasticizer, the synthetic resin used for the base layer according to the present invention may further comprise, if necessary, a stabilizer, a lubricant, a coloring agent, a processing agent which is used for processing a usual thermoplastic resin composition. Auxiliaries, antioxidants, antistatic agents, fillers and the like can be added.

In the present invention, the synthetic resin used for the surface layer of the multilayer waterproof sheet for outdoor laying may be the same as the synthetic resin used for the base layer or a synthetic resin compatible with the synthetic resin. Can be used. Among them, a soft polyvinyl chloride resin, or a homopolymer of methacrylic acid or methacrylic acid ester, or a copolymer of these with ethylene, propylene, vinyl acetate, or the like can be used, and these can be used alone or as a mixture of two or more kinds. Can also be used as

Further, the synthetic resin used for the surface layer of the present invention may contain, if necessary, a stabilizer, a lubricant, an ultraviolet absorber, an ultraviolet absorber, a colorant, which are used for processing a usual thermoplastic resin composition. , A processing aid, an antioxidant, an antistatic agent and the like can be added.

Here, the case where the resin component of the surface layer is a polyvinyl chloride resin and a plasticizer is added to the resin component is described. As the plasticizer, a phthalate ester plasticizer is preferable. The amount is suitably from 40 to 100 parts by weight based on 100 parts by weight of the resin component.

The case where an ultraviolet ray shielding agent is added to the surface layer is described. Examples of the ultraviolet ray shielding agent include zinc oxide, titanium oxide, calcium carbonate, cerium oxide, silica, aluminum hydroxide, magnesium hydroxide, and hydroxide. Examples include calcium, carbon black, white carbon, zeolite, and graphite. In this case, the added amount of the ultraviolet shielding agent is 0.1 to 20 parts by weight based on 100 parts by weight of the resin component. If the amount is less than 0.1 part by weight, a sufficient ultraviolet shielding effect cannot be obtained. If it exceeds, no further effect can be obtained anymore, and it is rather uneconomical.

The thickness of the multilayer waterproof sheet for outdoor laying according to the present invention is, like the conventional waterproof sheet, the total thickness in the range of 1.0 to 3.0 mm. Here, of the total thickness, the thickness occupied by the surface layer is 0.01 to 0.
The range is 8 mm. In this case, the total thickness is 1.0 m
If it is less than m, the mechanical strength of the waterproof sheet is particularly insufficient and it is not suitable for use. If it exceeds 3.0 mm, not only the construction work becomes difficult, but there is no further effect on the function, and it is uneconomical. As described above, the thickness of the surface layer is set to 0.01 to 0.8 mm. However, if the thickness is less than 0.01 mm, the absolute amounts of various component materials added to the thermoplastic resin as a main component become insufficient. , Does not contribute to the expected improvement in properties such as weather resistance, and if it exceeds 0.8 mm, the amount of addition does not impair the thermal stability or mechanical properties of the surface layer itself and does not cause a bleed phenomenon. In the following, even if the absolute amount of each of the above-mentioned agents can be increased, a further effect of improving the weather resistance cannot be expected, and it is rather uneconomical. Therefore, in the present invention, the overall thickness of the multilayer waterproof sheet for outdoor laying is set to 1.0 to 3.0 mm, and the thickness of the surface layer is set to 0.0 to 3.0 mm.
1 to 0.8 mm.

Next, the means for forming the multi-layer waterproof sheet for outdoor laying of the present invention will be described. The sheet employs a known co-extrusion molding method which is usually used for producing a multilayer product made of a thermoplastic resin. It is formed by a flat T-die having a multilayer structure.

The T-die system in this case is preferably a feed block system in which a resin material in a heated and molten state is multi-layered before flowing into the T-die, or a multi-manifold system in which a resin material is multi-layered inside the T-die. Adopted to. Note that T
The dual-slot type, which is stacked immediately after the die flows out, is inferior in the bonding property between the respective layers, and is therefore excluded from the present invention. Therefore, in the present invention, the term "compounds formed in a heated and melted state" means that the compounded raw materials of the respective layers are integrated into a multi-layered state under a heated and melted state before reaching the lip of the T-die. Means something.

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a multilayer waterproof sheet for outdoor laying according to the present invention will be described with reference to the drawings showing examples.

FIGS. 1 and 2 are cross-sectional views showing the structure of a multilayer waterproof sheet for outdoor laying of the present invention. FIG. 1 shows a first embodiment of the present invention, in which a surface layer (2) is formed into a multi-layer state on one surface of a base layer (1) under a heated and molten state, and is integrated into a multi-layer waterproof sheet for outdoor laying. (3a) is shown. FIG. 2 shows a second embodiment of the present invention, in which surface layers (2) and (2) are made into a multi-layer state under a heat-melting state on both surfaces of a base layer (1), and are integrated into an outdoor laying. 2 shows a multi-layer waterproof sheet (3b).

It is of course possible to use the sheets of FIGS. 1 and 2 to form a composite sheet in which a net-like woven fabric or non-woven fabric is sandwiched and integrated like a conventional waterproof sheet.

[0027]

Next, the present invention will be described with reference to Examples and Comparative Examples. Examples and comparative examples described below were directed to the multilayer structure of the outdoor waterproof multilayer waterproof sheet of the first embodiment shown in FIG.

Examples 1 to 6 First, each of the components shown in Table 1 used for the base layer (1) and the surface layer (2) of the multilayer waterproof sheet (3a) for outdoor laying of the present invention was selected. 2 were blended in the ratio shown
Each compound was mixed with a Henschel mixer to obtain a mixed raw material for each example.

[0029]

[Table 1]

[0030]

[Table 2]

Next, each of the above mixtures was extruded into two extruders (one for the base layer: one with a diameter of 55 mm, and one for the surface layer: one with a diameter of 40 mm).
Melt and knead each other in a heated and melted state by means of a table), introduced into a multi-manifold type T-die (lip width 550 mm), extruded in a two-layered multi-layer state, and cooled and solidified into a sheet by a conventional method. Thus, a two-layer integrated sheet was obtained.
The thickness of each layer was 1.8 mm for the base layer and 0.2 mm for the surface layer.
mm, the sheet was finished into a two-layer multilayer sheet having an overall thickness of 2.0 mm.

Next, the two-layer multilayer sheet obtained above was tested according to the following test items, and evaluated as a multilayer waterproof sheet for outdoor laying. The results are shown in Table 3.

[Test Method and Evaluation Method] -Laminability- The two-layer multi-layer sheet was cut into a 50 × 50 mm square, left in a heating oven at 150 ° C. for 5 minutes, and then peeled off between the layers by hand. And visually observe the state at that time,
Those that did not peel were rated good (O) and those that peeled were poor (x).

-Weather resistance- Black panel temperature: 80 ° C.-Fluorescent ultraviolet ray irradiation: 4 hours, black panel temperature: 50 ° C., humidity: 90% RH, 4 hours using a Dew panel light control weather meter (DPWL-5R manufactured by Suga Test Instruments Co., Ltd.) Under the cycle conditions described above, a weather resistance promotion test was performed at two levels of 2000 hours and 4000 hours, and the area ratio (%) of cracks generated on the surface irradiated with ultraviolet rays was calculated for each sample after the test. In addition,
The crack area ratio was determined by binarizing an enlarged surface image of the sample after the test using an image processing apparatus (Luzex FS manufactured by Nireco Co., Ltd.), and measuring the proportion of the crack portion.

-Economics- The amount of the ultraviolet shielding agent added to the entire multilayer waterproof sheet for outdoor laying was shown by weight fraction (%).

Table 3 shows the results of each of the above examples relating to the lamination property, weather resistance and economy. According to Table 3, the lamination property is good (良) in all of the examples, the weather resistance is relatively low in the incidence of cracks as indicated by the crack area ratio (%), and the economical efficiency is also an ultraviolet shielding agent. The weight fraction (%) of the amount added was small relative to the entire waterproof sheet, and the economic efficiency was good.

[0037]

[Table 3]

Comparative Examples 1 to 4 First, Comparative Example 1 was prepared by calendering a mixture of the same components as those of the surface layer (2) of Example 2 in the same ratio and having a thickness of 0.2 mm. A soft polyvinyl chloride film was prepared, and then a mixture obtained by mixing the same components as in the base layer (1) of each example in the same ratio was mixed by a Henschel mixer, and the thickness was determined by a T-die method using a normal single extruder. While extruding a sheet having a thickness of 1.8 mm, the above-mentioned flexible polyvinyl chloride film was laminated on the sheet by a conventional method to obtain a sheet having a multilayer structure of two layers having a total thickness of 2.0 mm.

In Comparative Example 2, the base layer (1) of each Example was used.
While extruding a 2.0 mm thick sheet by a T-die method using a single extruder in the same manner as in Comparative Example 1, a 0.05 mm thick acrylic film was laminated on the sheet with the same composition as in Comparative Example 1. And it was set as the sheet-like thing of the multilayer structure laminated | stacked on two layers.

Further, Comparative Example 3 was a composition similar to the base layer (1) of each Example, and Comparative Example 4 was a composition obtained by further adding an ultraviolet shielding agent to the composition of Comparative Example 3. Was extruded by a T-die method using a single extruder to obtain a single-layered sheet having a thickness of 2.0 mm.

The proportions of the components in each layer of Comparative Examples 1 to 4 are also shown in Table 2.

Comparative Examples 1 and 2 obtained above
The same test and evaluation as in the example were performed for the sheet-like material. As shown in Table 3, the results of each test are good in the comparative example 1 in terms of the weather resistance in view of the relatively small crack area ratio (%), but in the softness of the comparative example 1 in the laminating property. Neither the polyvinyl chloride film nor the acrylic film of Comparative Example 2 was peeled off, and both were defective (x). Comparative Example 3 was a sheet-like material having a large crack area ratio (%) and clearly poor weather resistance. Further, in Comparative Example 4, the weight fraction (%) of the ultraviolet ray shielding agent was remarkably large as compared with each of the examples, and the added amount was obviously wasted.

[0043]

As described above, the multi-layer waterproof sheet for outdoor laying of the present invention is a synthetic resin waterproof sheet used as a roofing material or the like, and has a multi-layer structure having a surface layer on one or both sides of a base layer. In the co-extrusion method, the base layer and the surface layer are formed in a multi-layered state under a heated and melted state until the compounding raw materials of the respective layers reach the lip of the T-die. Not only has good bonding properties, but also has extremely good lamination properties between layers, and has excellent mechanical properties, crack resistance, etc., and does not deteriorate its durability even when used outdoors for a long time. .

In particular, it is possible to select the component blending and blending amounts of the surface layer and the base layer so that the initial functions required for each layer can be freely exhibited, and the surface layer can be combined with the base layer under the condition of heating and melting. As a result of being in a layered state, it can be a multilayer waterproof sheet for outdoor laying with little delamination between layers, so that the waterproof sheet having high durability and a sufficient waterproof function can be obtained. is there.

Further, the multilayer waterproof sheet for outdoor laying of the present invention can simultaneously exhibit the economic effect of being able to be manufactured at low cost by a conventional manufacturing method.

Further, since the surface layer is made smaller in thickness than the base layer, and it is possible to add a component material for improving the function intensively only to the surface layer, the thermal stability and mechanical physical properties of the surface layer itself are improved. And the like, and there is an advantage that the deterioration phenomenon of the surface layer can be stopped by the surface layer itself and does not affect the base layer.

Further, in the present invention, a soft polyvinyl chloride resin is used for the base layer, and the surface layer is made of the same kind of soft synthetic resin as the base layer, or a different kind of soft synthetic resin having compatibility with the base layer. Therefore, the workability of the construction of the multilayer waterproof sheet for outdoor laying can be maintained as before.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a structure of a multilayer waterproof sheet for outdoor laying of the present invention, showing a first embodiment.

FIG. 2 is a sectional view showing a structure of a multilayer waterproof sheet for outdoor laying of the present invention, showing a second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Base layer 2 ... Surface layer 3a ... Multilayer waterproof sheet for outdoor laying 3b ... Multilayer waterproof sheet for outdoor laying

Claims (2)

[Claims] 1. A synthetic resin waterproof sheet used as a roofing material or the like, having a multilayer structure having a surface layer on one or both sides of a base layer, wherein the base layer and the surface layer are formed by co-extrusion molding. A multi-layer waterproof sheet for outdoor laying, wherein the compounding raw materials are made into a multi-layer state under a molten state by heating each other before reaching a lip of a T-die. 2. The substrate according to claim 1, wherein the base layer is made of a soft polyvinyl chloride resin, and the surface layer is made of a soft synthetic resin of the same kind as the base layer or a soft synthetic resin of a different kind compatible with the base layer. Multi-layer waterproof sheet for outdoor laying.