JPH11236552A - Waterproof seal material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively use a closed structure or a foamed structure having both closed cells and open cells as a fixed watertight seal material. SOLUTION: At least one surface of a foamed structure having closed cells or both closed cells and open cells has a storage modulus at room temperature [G '] of 2 × 10 ⁶ dyne / cm ² or more,
A layer made of an adhesive composition having an adhesive strength at room temperature of 500 g / 20 mm width or more is provided to constitute a water-sealing seal material A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixed watertight seal material using a foamed structure having closed cells or both closed cells and open cells.

[0002]

2. Description of the Related Art Rubber foams have excellent cushioning properties and are useful for applications such as cushioning materials and padding materials. Comparing closed cells and open cells in the foamed structure, the former has a structure in which the cells are separated by partitions in a three-dimensional lattice, whereas the latter removes the partitions between the series of separated cells. The latter is easier to deform mechanically. However, open cells cannot expect a water-stopping effect at all, whereas closed cells can expect a water-stopping effect due to the partition between the cells.

A foamed structure having both closed cells and open cells (hereinafter sometimes referred to as a semi-semi-open cell structure) is used to fill complicated gaps due to easy deformation based on open cells. It is suitable as a standard waterproof sealing material to be used by filling in complicated gaps because it can be expected to have both easy easiness and waterproofness based on closed cells.

[0004]

However, according to the results of tests conducted by the present inventors, it has been found that a closed-cell foamed structure or a half-semi-sealed foamed structure is used as a water-sealing material. With the passage of time, the repulsive stress of the foamed structure is relieved, and accordingly, the contact surface pressure between the foamed structure and the adherend interface decreases, and water leakage occurs along this interface,
It was found that it could not be used effectively as a waterproof sealing material.

[0005] To solve this problem, a method of providing an adhesive layer on both sides of the foamed structure and sealing the interface of the adherend with an adhesive is considered. However, if general acrylic or rubber-based pressure-sensitive adhesives are used as the pressure-sensitive adhesive layer, these pressure-sensitive adhesives will develop an adhesive force at the same time as assembly, which will hinder sealing work such as positioning and repositioning. Cheap.

In view of such circumstances, the present invention provides a fixed waterproof seal material by providing a specific pressure-sensitive adhesive layer on a closed cell or a foamed structure having both closed cells and open cells. The purpose is to enable it to be used effectively.

[0007]

Means for Solving the Problems The present inventors have conducted intensive studies on the above objects and found that the storage elastic modulus at room temperature on the surface of a closed-cell foamed structure or a half-semi-sealed foamed structure was obtained. And when a layer made of a pressure-sensitive adhesive composition having a specific adhesive strength is provided, when the layer is assembled to a portion where water is stopped, the above layer does not have tackiness, so that it does not immediately adhere, but It is easy to align and reposition, and sealing work can be performed without hindrance.Furthermore, after assembling, it gradually adheres due to the repulsive force of the foam structure, and the interface between the surface of the foam structure and the part where water is stopped Knowing that the sealing property is improved, the present invention was completed.

That is, according to the present invention, at least one surface of a foamed structure having closed cells or both closed cells and open cells has a storage elastic modulus [G '] at room temperature of 2 × 1.
0 ⁶ dyne / cm ² or more, adhesive strength at room temperature is 500 g / 20 m
The present invention relates to a water-sealing material (Claim 1) characterized in that a layer made of an adhesive composition having a width of not less than m is provided. Further, according to the present invention, a storage elastic modulus [G '] at room temperature on one surface of the foamed structure is 2 × 10 ⁶ dyne / cm ^2.
As described above, a layer made of an adhesive composition having an adhesive force at room temperature of 500 g / 20 mm or more is provided, and an adhesive layer different from the above-mentioned adhesive composition is provided on the opposite surface. The present invention relates to a water-sealing material having the above configuration.

In this specification, the storage elastic modulus [G '] of the pressure-sensitive adhesive composition refers to the shear storage elastic modulus of the above-mentioned composition, which is the storage of energy using external stress as strain. It is what should be called an elastic component, using a dynamic viscoelasticity measurement device RDS-II manufactured by Rheometrics,
The value is measured at a frequency of 1 Hz using a parallel plate jig having a sample thickness of about 1.5 mm and a diameter of 7.9 mm.

In the present specification, the adhesive strength of the pressure-sensitive adhesive composition is determined by attaching a sample (adhesive tape) to an acrylic plate (polymethyl methacrylate) as an adherend,
Atmospheric temperature 23 ° C, sticking time 30 minutes, peeling speed 30
It means 180 ° peel adhesion measured under the condition of 0 mm / min.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The pressure-sensitive adhesive composition used in the present invention has a storage elastic modulus [G '] at room temperature of 2 × 10 ⁶ dy.
ne / cm ² or more, preferably 5 × 10 ⁶ dyne / cm ² or more (usually 5 × 10 ⁷ dyne / cm ² or less), and an adhesive force at room temperature of 500 g / 20 mm or more, Preferably about 1 kg / 20 mm width or more (usually 10 kg
/ 20 mm width or less). Such a pressure-sensitive adhesive composition does not show tack and can be re-peeled without damaging the adherend if it is a short time of about several seconds after application, and thus alignment and repositioning are easy. On the other hand, it has a unique and useful characteristic of exhibiting high adhesive strength without requiring complicated steps such as heat treatment.

The pressure-sensitive adhesive composition having such properties is as follows:
The composition is not particularly limited as long as it has the above storage elastic modulus [G '] and the above adhesive strength. In general, a crosslinking agent such as a polyisocyanate compound is added to a polymer for forming the pressure-sensitive adhesive to carry out a crosslinking treatment, and the above-mentioned storage modulus [G '] and the above-mentioned storage modulus [G'] are selected depending on the selection of the polymer and the degree of the crosslinking treatment. Those set to the adhesive strength are preferably used.

As the polymer for forming the pressure-sensitive adhesive, an aliphatic polyester having a carbonate bond, that is, the following formula: (Wherein R is a linear or branched hydrocarbon group having 2 to 20 carbon atoms), particularly a polymer having a repeating unit represented by the following formula: The polyester to be synthesized is preferably used. The glass transition temperature (loss modulus; G "peak) is -3.
Polyester having a temperature of 5 ° C. or lower is also preferably used. Further, in addition to such aliphatic polyesters, acrylic polymers and the like can also be used.

The pressure-sensitive adhesive composition of the present invention may contain various conventionally known tackifiers. The blending of the tackifier may make it easier to balance tackiness and heat resistance. In addition, various conventionally known additives such as inorganic or organic fillers, powders such as metal powders and pigments, particles, and foils can be arbitrarily added. Furthermore, the durability may be further improved by blending various antioxidants.

The foamed structure used in the present invention comprises:
Various known cells can be used as long as they have closed cells or both open and closed cells. For the production of this foamed structure, natural rubber or synthetic rubber (chloroprene rubber, ethylene propylene terpolymer, etc.), vulcanizing agents, foaming agents, fillers, etc. are used in Banbury mixers and pressure kneaders. After kneading with a kneading machine, it is continuously kneaded by a calendar, an extruder, a conveyor belt casting, etc., and formed into a sheet shape and rod shape.
This is heated to be vulcanized and foamed, and if necessary, the vulcanized foam is cut into a predetermined shape, or natural rubber or synthetic rubber, a vulcanizing agent, a foaming agent, a filler, etc. are mixed in a mixture. For example, a method of vulcanizing, foaming, and molding the kneaded composition in a mold by a batching method can be used.

[0016] The waterproof sealing material of the present invention comprises a layer comprising the above-mentioned pressure-sensitive adhesive composition on such a foamed structure.
It is provided with a thickness of 100 μm. How to set
A direct coating method may be used, or a method in which the sheet is provided on release paper and then bonded thereto. The layer composed of the above-mentioned pressure-sensitive adhesive composition may be provided not only on one side but also on both sides of the foamed structure. Further, in providing a layer made of the above-mentioned pressure-sensitive adhesive composition, a composite layer may be provided, such as providing another pressure-sensitive adhesive layer or a substrate as a lower layer.

When a layer comprising the above-mentioned pressure-sensitive adhesive composition is provided only on one side of the foamed structure, a pressure-sensitive adhesive layer different from the above-mentioned pressure-sensitive adhesive composition, for example, The acrylic pressure-sensitive adhesive layer or the rubber-based pressure-sensitive adhesive layer may be provided. In this case, it is possible to easily perform positioning and positioning by using a layer made of the above-mentioned pressure-sensitive adhesive composition having no tack provided on one surface side, and to perform the characteristics of the general-purpose pressure-sensitive adhesive layer on the opposite side. Can also be demonstrated.

[0018]

EXAMPLES Next, examples of the present invention will be described in more detail. In the following, “parts” means “parts by weight”.

Example 1 The following composition was kneaded with a mixture of mixins, and the kneaded product was heated in an oven at 160 ° C. for 30 minutes to form a vulcanized foam, taken out of the oven, and After cooling, some of the air bubbles were broken by a pressurization method to obtain a half-semi-half-cell foamed structure. The specific gravity of this foamed structure was 0.11 g / ml.

<Blending composition of foamed structure> Ethylene propylene terpolymer 100 parts Zinc flower 5 parts Stearic acid 1 part Carbon 40 parts Polyethylene 20 parts Heavy calcium carbonate 180 parts Polybutene 40 parts Sulfur 2 parts Mercapto Benzothiazole 1 part Zinc diethyldithiocarbamate 2 parts Azodicarboxylic acid amide 13 parts

On the other hand, in a four-necked separable flask equipped with a stirrer, a thermometer and a water separation tube, a liquid polycarbonate diole [PLA manufactured by Daicel Chemical Industries, Ltd.
CCEL CD210PL ", hydroxyl value 115KOHmg
/ G] 250 g (hydroxyl group: 0.512 equivalents), 51.8 g sebacic acid (acid group: 0.512 equivalents), dibutyltin oxide (hereinafter referred to as DBTO) 12 as a catalyst
7 mg was charged, the temperature was raised to 180 ° C. while stirring was started in the presence of a small amount of toluene as a reaction water discharge solvent, and the temperature was maintained. After a while, effluent separation of water was observed, and the reaction began to proceed. The reaction was continued for about 24 hours to obtain a polyester having a weight average molecular weight of 55,000.

After diluting the polyester with toluene to a solid concentration of 40% by weight, a trimer adduct of hexamethylene diisocyanate of trimethylolpropane is used as a crosslinking agent per 100 parts (solid content) of the polyester [Nippon Polyurethane "Coronate HL" manufactured by K.K.) was added to prepare a pressure-sensitive adhesive composition.

The pressure-sensitive adhesive composition thus prepared is applied to one surface of the above-mentioned semi-semi-continuous foam structure by an applicator, and dried at 130 ° C. for 5 minutes to form a 30 μm-thick pressure-sensitive adhesive. A layer composed of the agent composition was formed. Further, an acrylic pressure-sensitive adhesive layer having a thickness of 150 μm was provided on the opposite side of this layer to obtain a waterproof sealing material.

For measuring the adhesive strength, the above-mentioned pressure-sensitive adhesive composition was applied on a 38 μm-thick polyethylene terephthalate film (hereinafter referred to as PET film) by an applicator, After drying for 30 minutes, a layer composed of a pressure-sensitive adhesive composition having a thickness of 30 μm was formed, and aging was carried out in an atmosphere at 50 ° C. for 5 days to prepare a pressure-sensitive adhesive tape. Further, in the same manner as described above, a thickness of 50 μm
A μm pressure-sensitive adhesive layer was formed.

Example 2 A four-necked separable flask equipped with a stirrer, a thermometer and a water separation tube was charged with a liquid polycarbonate dial [PLACCELCD 220 manufactured by Daicel Chemical Industries, Ltd.].
PL ", hydroxyl value 56.1 KOH mg / g] 250 g (hydroxyl group: 0.25 equivalent), azelaic acid 23.5 g (acid group: 0.25 equivalent), 62 mg of DBTO as a catalyst, and a reaction water discharge solvent In the presence of a small amount of toluene, the temperature was raised to 180 ° C. while stirring was started, and maintained at this temperature. After a while, effluent separation of water was observed, and the reaction began to proceed. The reaction was continued for about 25 hours to obtain a polyester having a weight average molecular weight of 78,000.

After diluting the polyester with toluene to a solid content concentration of 40% by weight, per 100 parts (solid content) of the polyester, as a crosslinking agent, an adduct of a trimethylolpropane tolylene diisocyanate trimer [Nihon Polyurethane ( "Coronate L" manufactured by K.K.) 1.5 parts (solid content)
Was added to prepare a pressure-sensitive adhesive composition. A water-blocking seal material was obtained in the same manner as in Example 1 except that this pressure-sensitive adhesive composition was used. In the same manner as in Example 1, an adhesive tape for measuring adhesive strength was prepared. Further, a pressure-sensitive adhesive layer for storage elastic modulus measurement was formed in the same manner as in Example 1.

Example 3 The following composition was kneaded with a mixture of mixin, and the kneaded product was heated in an oven at 160 ° C. for 30 minutes to be vulcanized and foamed to form a closed-cell foamed structure. Obtained. The specific gravity of this foamed structure was 0.10 g / ml.

<Composition of foamed structure> Ethylene / propylene / terpolymer 40 parts Butyl rubber 60 parts Zinc white 5 parts Stearic acid 3 parts Carbon 50 parts Heavy calcium carbonate 50 parts Process oil 20 parts Sulfur 0. 5 parts Mercaptobenzothiazole 1 part Zinc diethyldithiocarbamate 1 part Quinone dioxime 0.5 parts Quinone monooxime 0.5 parts Azodicarboxylic acid amide 20 parts

The adhesive composition prepared in Example 1 was applied to one side of the closed-cell foamed structure using an applicator and dried at 130 ° C. for 5 minutes to form a 30 μm thick adhesive composition. A layer made of the material was formed. Further, an acrylic pressure-sensitive adhesive layer having a thickness of 150 μm was provided on the opposite side of this layer to obtain a waterproof sealing material.

Comparative Example 1 Acrylic acid n was placed in a reaction vessel equipped with a stirrer and a thermometer.
-95 parts of butyl, 5 parts of acrylic acid, 150 parts of toluene,
0.1 part of azobisisobutyronitrile was added, and solution polymerization was performed at 60 ° C. for about 7 hours in a nitrogen gas atmosphere to obtain a polymer solution. Per 100 parts (solids) of this polymer, 2 parts (solids) of a tolylene diisocyanate trimer adduct of trimethylolpropane ["Coronate L" manufactured by Nippon Polyurethane Co.] as a crosslinking agent Was added to prepare a pressure-sensitive adhesive composition. A water-blocking seal material was obtained in the same manner as in Example 1 except that this pressure-sensitive adhesive composition was used. In the same manner as in Example 1, an adhesive tape for measuring adhesive strength was prepared. Further, a pressure-sensitive adhesive layer for storage elastic modulus measurement was formed in the same manner as in Example 1.

Comparative Example 2 Acrylic acid 2 was added to a reaction vessel equipped with a stirrer and a thermometer.
-80 parts of ethylhexyl, 20 parts of acrylic acid, Irgakiure-184 (manufactured by Ciba-Geigy) as a photopolymerization initiator
After adding 0.6 part and sufficiently replacing with nitrogen gas, the mixture was irradiated with ultraviolet rays by a high-pressure mercury lamp at an irradiation amount of about 100 mj / cm ² . To the viscous material obtained by this irradiation, trimethylolpropane triacrylate was used as an internal crosslinking agent.
And a polymerizable composition was prepared.

The polymerizable composition thus prepared is coated on a release paper with an applicator so as to have a thickness of 30 μm, and then coated with a release paper to eliminate polymerization inhibition by oxygen. About 1,400m by mercury lamp
The adhesive layer was formed by irradiating ultraviolet rays at an irradiation amount of j / cm ² . This pressure-sensitive adhesive layer was adhered to both sides of the half-semi- and semi-continuous foamed structure obtained in Example 1, and the release paper was removed to obtain a waterproof sealing material.

For the measurement of adhesive strength, the above polymerizable composition was coated with a 30 μm-thick PE by an applicator.
After being coated on a T film so as to have a thickness of 30 μm, in order to eliminate polymerization inhibition by oxygen, the film is covered with release paper, and irradiated with ultraviolet rays by a high pressure mercury lamp at an irradiation amount of about 1,400 mj / cm ^2. Thus, an adhesive layer was formed to prepare an adhesive tape. In the same manner as above, a pressure-sensitive adhesive layer having a thickness of 50 μm was formed on release paper for storage elastic modulus measurement.

In Examples 1 and 2 and Comparative Examples 1 and 2, the pressure-sensitive adhesive layer formed for measuring the storage elastic modulus
The storage elastic modulus and adhesive strength at room temperature were measured using an adhesive tape prepared for measuring adhesive strength. The results were as shown in Table 1.

[0035]

Next, for each of the water-sealing materials of Examples 1 to 3 and Comparative Examples 1 and 2, as a water-stop test, a U-shaped water-stop test and a high-pressure water-stop were performed by the following method. The test was performed. The results were as shown in Table 2 below.

<U-shaped water stoppage test>
Sample A was formed into a cord having a rectangular cross section of 0 mm and a width of 10 mm. This sample A is U-shaped as shown in FIGS. 1 and 2 and is sandwiched between two acrylic plates 1 and 1. Fastened with bolts and nuts 3. The compressibility in the thickness direction of the sample A was adjusted by the thickness of the spacer 2.
After the bolts and nuts 3 have been fastened in this way, as shown in FIG.
Was put. As a U-shaped water stoppage test, it was examined whether the water stoppage was possible when the compression ratio in the thickness direction of sample A was set to what percentage.

<High-pressure running water stoppage test> A water-stop seal material was processed into a donut shape having a thickness of 10 mm, an outer diameter of 100 mm, and an inner diameter of 80 mm to obtain a sample B. This sample B was prepared as shown in FIGS.
As shown in (1), the acrylic plate 1 and the acrylic molded body 5 were fastened with bolts and nuts 3 while being held between the acrylic plate 1 and the acrylic molded body 5 and maintaining the space by the spacer 2 passed through the bolt portion. . The compressibility in the thickness direction of the sample B was adjusted by the thickness of the spacer 2. After fastening with bolts and nuts 3 in this manner, 80 kgf /
Water was applied for 3 minutes at the pressure of cm ^{2 to} the portion of the waterproof seal material. When the compression ratio in the thickness direction of the sample B was set to what percentage, whether or not the water could be stopped was examined.

[0039]

As is evident from the results of Tables 1 and 2, each of the waterproof sealing materials of Examples 1 to 3 of the present invention is made of a polyester provided on one surface of a foamed structure. Since the layer made of the adhesive composition does not show tack at room temperature, it is easy to perform alignment and repositioning at the time of assembling and has excellent sealing workability. It can be seen that a very good water-stopping property was obtained even at a compressibility, and that the water-stopping property did not decrease even if the repulsion stress was relaxed over time, and that the water-stopping property was high even with high-pressure running water.

On the other hand, in the water-sealing material of Comparative Example 1 in which an adhesive layer different from that of the present invention was provided on the foamed structure, good water-stopping property was obtained due to the large adhesive strength of the above-mentioned adhesive layer. However, since the pressure-sensitive adhesive layer shows tack at room temperature, it is difficult to perform positioning and repositioning at the time of assembly.
Low workability. In the water-sealing seal material of Comparative Example 2, contrary to the above, alignment and repositioning are easy, but since the adhesive force of the adhesive layer is small, it is difficult to obtain good water-tightness. .

[0042]

As described above, the present invention provides a structure in which a layer made of a specific adhesive composition is provided on at least one surface of a closed cell or a foamed structure having both open cells and closed cells. In addition, it is possible to provide a fixed waterproof seal material which can easily perform the sealing work and exhibits high sealing properties after assembling. Also, by providing a layer made of the above-mentioned pressure-sensitive adhesive composition on one surface and providing a general-purpose pressure-sensitive adhesive layer such as an acrylic or rubber-based material on the other side, the characteristics of the general-purpose pressure-sensitive adhesive layer are also provided. It is possible to provide a fixed water seal material that can be used effectively.

[Brief description of the drawings]

FIG. 1 is a side view showing an apparatus configuration of a U-shaped water stop test of a water stop seal material.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a cross-sectional view showing a state in which water is poured into a U-shaped sample (water-blocking seal material) in the apparatus configuration of FIGS. 1 and 2;

FIG. 4 is a side view showing an apparatus for a high-pressure running water stoppage test of the watertight seal material.

FIG. 5 is a sectional view taken along line VV in FIG. 4;

[Explanation of symbols]

 A and B samples (water seal material) 1 Acrylic plate 2 Spacer 3 Bolt and nut 4 Water 5 Acrylic molded body

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09J 175/06 C09J 175/06

Claims (2)

[Claims] 1. A storage structure having a storage elastic modulus [G '] of at least 2 × 10 ⁶ dyne / cm ² at room temperature on at least one surface of a foamed structure having closed cells or both closed and open cells. A water-blocking sealant comprising a layer made of an adhesive composition having an adhesive strength at room temperature of 500 g / 20 mm width or more. 2. An adhesive composition having a storage elastic modulus [G '] of at least 2 × 10 ⁶ dyne / cm ² at room temperature and an adhesive strength at room temperature of at least 500 g / 20 mm width on one surface of the foamed structure. 2. The waterproof sealing material according to claim 1, wherein a layer made of a material is provided, and an adhesive layer different from the adhesive composition is provided on the opposite surface.