JPH06313065A - Sealing material for exterior wall plate - Google Patents

Abstract

PURPOSE:To obtain a sealing material for exterior wall plate absolutely free from bleeding of mineral oil, etc., caused by the deterioration of the sealing material and usable over a long period without causing the staining of the joint part of the wall plate. CONSTITUTION:This sealing material is produced by compounding 100wt.% of a styrene-based synthetic rubber, preferably a styrene-ethylene-butylene-styrene synthetic rubber with 30-70wt.% of one or more kinds of resins selected from amorphous ethylene-propylene copolymer, low-molecular propylene resin, polybutene resin, butadiene resin and polyisoprene resin and incorporating the obtained elastomer with necessary amounts of a tackifier, a wax and a stabilizer. The use of the amorphous ethylene-propylene copolymer, etc., as a substitute for mineral oil is effective for imparting the sealing material with viscoelasticity and completely eliminating the bleeding of the additives.

Description

Detailed Description of the Invention [Industrial applications]

The present invention relates to a sealing material for exterior wall plates.

[0002]

2. Description of the Related Art Conventionally, an inorganic wall board made of fiber reinforced cement board has been widely used as a building board material. This seed wall plate is made of the same material and can be mass-produced industrially, and since it does not consume natural resources such as wood, it has a favorable advantage in terms of resource protection.

However, since these inorganic wallboards have a characteristic that they have no compressive elasticity and are hard and easily cracked, it is difficult to fix them by nailing, and the adhesion between the wallboards at the joint cannot be sufficiently obtained. In order to solve such a problem, these wall plates are usually engaged with each other at an engaging step portion AB which is mated with each other as shown in FIG.
Is provided, the wall plates are connected to each other at this portion, and a sealing material C made of synthetic rubber or the like is inserted in order to prevent rainwater from penetrating from the joint step.

By the way, this sealing material made of synthetic rubber has a property that it is easily compressed and deformed by the pressure P applied between the wall plates W between the joint steps, and at the same time, the joint steps A and B are closely adhered to each other without a gap. Must have,
In order to impart these properties, conventionally, styrene-butadiene-styrene copolymer (SBS) or styrene
A sealing agent C was used in which an elastomer obtained by adding mineral oil or the like as a softening agent to a styrene synthetic rubber such as isoprene-styrene copolymer (SIS) was further added with a tackifier.

[0005]

However, although the above-mentioned sealing agent C has no problem at the beginning of use, when the rubber component deteriorates with age due to contact with ultraviolet rays, oxygen, water, etc., the additive carrying ability of the synthetic rubber becomes poor. As a result, the mineral oil oozes out as shown by D in FIG. 2, and there is a problem that the mineral oil may leach out to the surface of the wall plate. When the mineral oil is leached to the surface of the wall plate in this way, there is a drawback that suspended dust and sand particles in the atmosphere adhere to it and the wall surface, especially the part along the joint, becomes very unsightly.

Moreover, since these inorganic wallboards have hygroscopicity, once the mineral oil permeates, the oil permeates into the interior of the wallboard tissue, so even if the surface is wiped and cleaned, it is not possible to completely dispel the leached oil. It was almost impossible, and if the harmful effect of mineral oil leaching occurred, it would be impossible to completely remove it.

[0007]

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a sealing material for exterior wallboard, which is free from leaching of mineral oil and the like and has no stain on the wallboard joint portion even after long-term use. It was made for the purpose.

[0008]

[Means for Solving the Problems] That is, the sealing material for exterior wall plates of the present invention is a low molecular weight propylene resin, polybutene resin, butadiene resin or polyisoprene resin based on 100% by weight of styrene synthetic rubber. One or more or an ethylene / propylene non-crystalline copolymer is added to the elastomer in an amount of 30 to 70% by weight, and a tackifier, a wax, and a stabilizer are added in the required amounts, and further. It is characterized in that styrene / ethylene / butylene / styrene synthetic rubber (SEBS) is used as the styrene-based synthetic rubber.

[0009]

In the present invention, the rubber component which is the basic compound of the sealant is styrene synthetic rubber or styrene / ethylene / butylene / styrene synthetic rubber (hereinafter abbreviated as "SEBS") different from these styrene synthetic rubbers. Styrene synthetic rubber is used. Among them, SEBS has good weather resistance and heat stability as compared with styrene / butadiene / styrene synthetic rubber (SBS) and styrene / isoprene / styrene synthetic rubber (SIS).

In order to impart the elasticity and tackiness required to this styrene synthetic rubber, the use of mineral oil is completely abolished in the present invention, and one kind selected from low molecular weight propylene resin, polybutene resin, butadiene resin and polyisoprene resin. The above or an ethylene / propylene amorphous copolymer is used. Due to their molecular structure, these impart viscoelasticity-rich properties to the above-mentioned styrene-based synthetic rubber as a base material. Although it is possible to add an ethylene / propylene amorphous copolymer to SBS and SIS for the above purpose,
The compatibility is poorer than that of SEBS, and it is rather unsuitable as the material of the sealing material.

The amount of one or more of the low-molecular-weight propylene resin, polybutene resin, butadiene resin and polyisoprene resin added or the amount of the ethylene-propylene amorphous copolymer added is 100% by weight of the styrene synthetic rubber. The reason why 30 to 70% by weight is added is that if it is less than 30% by weight, sufficient viscoelasticity, particularly elasticity, cannot be imparted, and it will not be easily deformed even if it is inserted between the joint steps of the wall plates. %, The viscoelasticity of the styrene-based synthetic rubber, particularly the viscosity becomes too low, and when inserted and compressed between the joint steps of the wall plates, it easily deforms and flows, and it becomes impossible to exert a sufficient sealing effect. is there. It exhibits appropriate viscoelasticity in the above range of 30 to 70% by weight. Further, since the ethylene-propylene amorphous copolymer has a high molecular structure, it has no fluidity, and as a result, it does not leach out even if the styrene synthetic rubber deteriorates.

Then, a necessary tackifier such as tackifier or paraffin is added to the elastomer. These are added in order to impart the tackiness of the sealing material between the joining step surfaces of the wall plate, and are appropriately added in consideration of the surface condition of the wall plate. Wax is added to help discharge from the nozzle of the seal material discharge gun, and C ₅ petroleum resin is preferably used. In addition, stabilizers are added to prevent oxidation of the sealing material, and the amount added is a necessary amount according to the purpose.

[0013]

EXAMPLES Next, examples of the present invention will be described.

[Examples 1 to 9] SEBS was used as a synthetic rubber component which is a basic composition of the sealing material, and an ethylene / propylene amorphous copolymer was added thereto as a composition shown in Examples 1 to 9 of Table 1. After uniform mixing with a mixing roll,
As shown in FIG. 1, width 2 to 3 is formed on the surface of the joining step portion 2A of the wall plate 1.
A sealing material 3 was obtained by extruding beads having a size of mm and a height of 1 to 1.5 mm. Then, the wall plate 1 was placed in a dryer at 60 ° C., and the exuding state of the additives was observed daily for one week. The results shown in the lower column of Table 1 were obtained.

Further, another wall plate 1 manufactured at the same time was fitted to the joining step portion 2B as shown in FIG. 2, and the deformed state of the sealing material 3 between the step surfaces was observed. It was found that the products had a small amount of deformation and required a pressure contact pressure, and the products of Examples 8 to 9 were easily flow-deformed even with a slight pressure, so that the so-called "stiffness" could not be obtained and a sealing effect could not be obtained.

[0016]

[Table 1]

Next, SEBS was used as a synthetic rubber component which is the basic composition of the sealing material, and an ethylene / propylene amorphous copolymer was added thereto in the same compounding amount as shown in Examples 1 to 9 in Table 1. Then, after uniformly mixing with a mixing roll, the mixture was heated and discharged from a nozzle while mixing nitrogen gas into a foamed state, and thereafter, the same tests as in Examples 1 to 9 were performed. The leaching test results for this example are Example 1
Although it was the same as -9, a fitting test was performed as shown in FIG.
It has been found that the one with 50% by weight shows very good viscoelasticity.

Next, a low molecular weight propylene resin, a polybutene resin, a butadiene resin and a polyisoprene resin were used in place of the ethylene / propylene amorphous copolymers of Examples 1 to 9 in the same manner as in the sealing material 3 and The foam sealing material 3 was obtained, and the same leaching test and sealing effect test were carried out on these, but the leaching amount and the viscoelastic effect were almost the same as in Examples 1-9.

As a comparative example, a styrene-butadiene-styrene copolymer (SBS) was used as a synthetic rubber component which is the basic composition of the sealing material, and 100% by weight of this synthetic rubber was used.
When a conventional sealing material with 30% by weight of mineral oil added and tackifier added to give tackiness was tested under the same conditions as in the example, 0.5 mm of mineral oil leaching was observed on the first day. After 1 week, the circumference of the sealing material is 2-3 mm
The mineral oil that had leached all over looked shining.

[0020]

As described above, according to the sealing material for exterior wall plates of the present invention, a low molecular weight propylene resin, polybutene resin, which does not leach as a member that imparts the necessary viscoelasticity to the sealing material, Since butadiene resin, polyisoprene resin or ethylene / propylene non-crystalline copolymer is used, even if the synthetic rubber as a carrier deteriorates, the surface of the wallboard will not be contaminated by the leaching substance and will be good for a long time. The appearance of the wallboard can be maintained. Furthermore, the low-molecular-weight propylene resin, polybutene resin, butadiene resin, polyisoprene resin, ethylene / propylene amorphous copolymer, and the like used in the sealing material for exterior wall plate of the present invention are inexpensive and therefore the sealing material for exterior wall plate. It also has various effects such that it can be manufactured and provided at low cost.

[Brief description of drawings]

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

FIG. 2 is a sectional view showing an example of a usage state of the embodiment of the present invention.

FIG. 3 is a fragmentary perspective view of a conventional example. [Brief Description of Drawings] 1 ... Wall plate 2A ... Joining step 2B ... Joining step 3 ... Sealing material

Claims (3)

[Claims] 1. A styrene-based synthetic rubber based on 100% by weight,
30-70% or more of low molecular weight propylene resin, polybutene resin, butadiene resin, polyisoprene resin
A sealant for exterior wallboard, which comprises a tackifier, a wax, and a stabilizer in necessary amounts with respect to an elastomer obtained by adding weight%. 2. With respect to 100% by weight of styrene synthetic rubber,
A sealant for exterior wallboard, which comprises an elastomer obtained by adding 30 to 70% by weight of an amorphous ethylene / propylene copolymer, and a tackifier, a wax and a stabilizer in required amounts. 3. The sealing material for exterior wall board according to claim 1, wherein the styrene synthetic rubber is styrene / ethylene / butylene / styrene synthetic rubber.