JPH065439Y2 - Heat-sealable waterproof sheet - Google Patents

Description

[Detailed Description of the Invention] (Industrial field of application) The present invention relates to a heat-sealable waterproof sheet. More specifically, it has excellent workability such as laying in complex places, joining sheets together, and after installation. Relates to a heat-sealable waterproof sheet that naturally crosslinks a rubber component by a large positive heat to improve the strength of a sheet joint portion and does not easily peel off from a base surface.

(Prior Art) As a heat-sealable waterproof sheet, a sheet-like polyolefin resin such as polyethylene, polypropylene, and ethylene-vinyl acetate (EVA), or a monoolefin-based copolymer partially or completely cross-linked to the above resin. A polymer rubber blended with flexibility, heat resistance, and impact resilience has begun to attract attention.

For example, a thermoplastic elastomer obtained by dynamically heat-treating a monoolefin copolymer rubber and a polyolefin plastic in advance and partially cross-linking the same has a density of 0.910 to 0.940 g.
Japanese Patent Laid-Open No. 59-18741 discloses a waterproof sheet formed by mixing ethylene polymer of 1 cm ³ / cm ³ and forming it into a sheet.

(Problems to be solved by the invention) However, in the conventional waterproof sheet of this type, first, a partially cross-linked or completely cross-linked product of a monoolefin copolymer rubber such as ethylene-propylene terpolymer is converted into a polyolefin plastic (for example, atactic PP). Mixing, preferably mixed under a nitrogen atmosphere, and then mixed with a polyolefin plastic into a sheet, so that if the degree of crosslinking of the partially crosslinked rubber is too small, heat resistance of the waterproof sheet, tensile properties, elastic recovery, It lacks rubber properties such as impact resilience. On the other hand, if the degree of cross-linking of the partially cross-linked rubber is too large, the flowability of the waterproof sheet is lowered and the formability is impaired.

In addition, when laying and installing a conventional heat-sealable waterproof sheet to a complicated part of the base, the waterproof sheet originally mixed with partially crosslinked rubber may lack flexibility,
There was also a drawback that it was difficult to come into close contact with the lower ground. Particularly in the winter, this tendency is remarkable, and a waterproof sheet having improved workability has been desired.

Moreover, the conventional waterproof sheet has a drawback that it is easily peeled off from the underlying surface due to contraction deformation of the waterproof sheet after being laid on the underlying surface.

The present invention solves these drawbacks, and it can be easily laid even in complicated places such as corners, and after the construction, it has sufficient trauma resistance by allowing natural crosslinking of the rubber component by the large positive heat. Another object of the present invention is to provide a heat-sealable waterproof sheet which prevents deformation of the sheet due to natural cross-linking and is resistant to peeling from the underlying surface.

(Means for Solving the Problems) That is, a feature of the present invention is that a vulcanizing agent and a vulcanization assistant are added to a mixture of a rubber component and a polyolefin resin, which are ethylene-propylene terpolymer, butyl rubber or a blend thereof. A heat-sealable waterproof sheet in which a reinforcing fiber member is embedded in a spontaneously crosslinkable thermoplastic elastomer layer containing.

(Function) That is, the waterproof sheet of the present invention is a thermoplastic elastomer containing a rubber component made of ethylene-propylene terpolymer, butyl rubber or a blend thereof and a polyolefin resin, and the rubber component is naturally cross-linked in the elastomer. It contains a vulcanizing agent and a vulcanization aid. Therefore, at the time of sheet molding, the rubber component is not cross-linked, so it has a high fluidity and is easy to mold, and the sheets can be joined by thermal cross-linking, and the sheet itself is also highly flexible, so that it does not come out It is excellent for sticking and mounting on complicated places such as corners and around drain pipes. In addition, after construction, the rubber layer naturally crosslinks due to the heat of the sun, which improves the adhesive strength at the joints of the sheets, and the strength of the sheets themselves also develops rubber-like properties, increasing external damage resistance and protecting the base. Can be done enough. Not only that, even if the thermoplastic elastomer layer tries to shrink and deform due to natural crosslinking of the rubber component, the reinforcing fiber member prevents this, so that the waterproof sheet laid on the base surface cannot be easily peeled off from the base surface. Absent.

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a longitudinal sectional view of a heat-sealing waterproof sheet according to the present invention. A heat-sealing waterproof sheet (1) has a reinforcing fiber member (3) embedded in a thermoplastic elastomer layer (2). The thermoplastic elastomer layer (2) is composed of ethylene-propylene terpolymer, butyl rubber or a blend thereof, and a natural vulcanization agent containing a vulcanizing agent and a vulcanization aid in a mixture containing a rubber component and a polyolefin resin. However, the polyolefin resin is ethylene, propylene, 1-butene, 3-methyl-1-butene, 1-
Hexane, 3-methyl-1-pentene, 4-methyl-1
A homopolymer or copolymer of α-olefin such as pentene or 1-octene, or a copolymer of α-olefin with a small amount (for example, 10 mol% or less) of another polymerizable monomer, for example, ethylene-acetic acid A vinyl copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-methacrylic acid copolymer, etc. are referred to, but an ethylene-vinyl acetate copolymer is preferable in order to improve flexibility.

The above-mentioned polyolefin resin has fluidity during molding of the thermoplastic elastomer, and enables heat fusion of the sheet joint portion during construction.

In the present invention, the addition amount of the rubber component and the polyolefin resin is 10 to 90 parts by weight of the rubber component and 9 parts by weight of the polyolefin resin.
It is 0 to 10 parts by weight, preferably 80 to 20 parts by weight of polyolefin resin with respect to 20 to 80 parts by weight of rubber content. If the rubber component is less than 10 parts by weight, the properties of the polyolefin resin dominate, resulting in lack of flexibility. or,
If the rubber component is 90 parts by weight or more, the heat fusion property will be poor.

Sulfur-based vulcanizing agent, P-quinone dioxime (GH
F) type, resin type, for example, olefin type, phenol type,
Examples include xylene type. Generally sulfur type, GHF
It is a system.

Further, the vulcanization aid mainly includes a vulcanization accelerator, such as tetramethyl thiuram monosulfide (TMTM), dipentamethylene thiuram tetrasulfide (DPTT),
Known vulcanization accelerators such as lead peroxide and trimene base are included. When the vulcanization agent is a sulfur-based vulcanization accelerator, super accelerators such as zinc di-n-butylthiocarbamate (ZnBDC) and dipentamethylene thiuram tetrasulfide ( DPTT)
However, the low-temperature vulcanizability is excellent and is particularly preferable.

A typical blending ratio of the thermoplastic elastomer of the waterproof sheet of the present invention is 1 to 6 parts by weight of a vulcanizing agent and 1 to 10 parts by weight of a vulcanization aid with respect to 100 parts by weight of a mixture of a polyolefin resin and a rubber component. And is appropriately used within this range.

In addition to vulcanizing agents and vulcanization aids, these may be stearic acid, ZnO, carbon black, inorganic pigments, organic pigments, inorganic fillers, tackifiers, and softeners used in ordinary rubber compounding, if necessary. It is mixed and mixed.

The rubber component, the polyolefin resin, the vulcanizing agent, the vulcanization aid, and the other fillers are mixed with a conventionally known kneading device such as a Banbury mixer, an internal mixer, or a kneader at a temperature not lower than the melting point of the polyolefin resin for about 1 to 15 minutes. The materials are melt-mixed to some extent, but the order of mixing is not particularly limited.

The mixture thus obtained can be formed into a sheet by molding with a calendar roll or an extruder for resin or rubber.

Further, the reinforcing fiber member (3) used in the present invention has a thickness of about 0.05 to 0.50 mm, and is made of inorganic fibers such as glass fiber and carbon fiber, or polyester, polyamide, polyolefin, polyvinyl alcohol and aromatic fiber. The organic fiber is a material such as polyamide and may be woven or non-woven fabric. The flexural rigidity (Kg / cm ² :
Adjusting ASTM D747). The flexural rigidity (Kg / cm ² : ASTM D747) of the waterproof sheet of the present invention is preferably 40 to 700. If it is less than 40 Kg / cm ^2, there is a necking phenomenon, that is, there is a risk of cutting the rubber sheet from a crack in the base. It becomes an area where the physical properties of the sheet are poor, and 700 Kg / cm ² or more is an area where the repulsion elasticity is large and it is difficult to fit in each part of the complicated part or the lower ground of the recess.

(Effect) Since the rubber sheet of the present invention is not cross-linked, the sheet itself is flexible, and it is possible to easily soften it by heating it during construction even in a compounded area where the relatively hard polyolefin resin is rich. , It also fits well on the ground below complex areas.

Then, particularly after sticking and applying on the base surface, the crosslinking of the rubber component progresses due to the heat of the sun and the high strength progresses to form a waterproof layer having high strength and scratch resistance.

In addition, the waterproof sheet of the present invention can be heat-sealed by using a hot air blower when joining the sheets together, and then naturally cross-linking with a large positive heat to further strengthen the joint portion. Will be possible.

Further, since the reinforcing fiber member laminated on the waterproof sheet of the present invention prevents the sheet from contracting and deforming due to natural crosslinking of the rubber component of the thermoplastic elastomer layer, peeling of the waterproof sheet from the lower ground occurs. Hateful.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of a heat-sealable waterproof sheet according to the present invention. (1) …… Waterproof sheet (2) …… Thermoplastic elastomer layer (3) …… Reinforcing fiber member

Claims (1)

[Scope of utility model registration request] 1. A spontaneously crosslinkable thermoplastic elastomer layer comprising a mixture of a rubber component consisting of ethylene-propylene terpolymer, butyl rubber or a blend thereof and a polyolefin resin, a vulcanizing agent and a vulcanization aid. A heat-sealable waterproof sheet comprising a reinforcing fiber member embedded therein.