JP3126439B2 - Method for producing olefin-based tarpaulin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a tarpaulin of an ethylene copolymer having excellent heat resistance, and more particularly to a method of adding a specific polyolefin resin to a specific ethylene copolymer and heating the mixture. The present invention relates to a method for producing an olefin-based tarpaulin obtained by joining and kneading a sheet obtained by kneading on both sides of a coarse base fabric.

[0002]

2. Description of the Related Art Conventionally, a typical tarpaulin of an ethylene copolymer is a product obtained by bonding a sheet of ethylene vinyl acetate (EVA) to both surfaces of a base fabric and integrating the same. Such a material has good cold resistance at low temperatures, does not contain a plasticizer, has no liquid elution, and is excellent in safety as compared with tarpaulin made of polyvinyl chloride (PVC). However, problems have often been pointed out regarding the strength at high temperatures due to the characteristics of the material. In particular, there are many problems regarding the strength of the welded portion, and when filling a high-temperature material (for example, resin) into the tarpaulin, there is a problem that the resin is broken by its own weight. The present inventors have conducted intensive studies to provide a tarpaulin of an olefin copolymer having a high welder adhesive strength at a high temperature without impairing safety, and as a result, a specific polyolefin resin is used as an ethylene copolymer. The present invention was completed by the addition.

[0003]

Means for Solving the Problems The present invention has taken measures to solve the above-mentioned problems. One of them is ethylene vinyl acetate, ethylene methyl methacrylate, ethylene ethyl acrylate or ethylene methyl acrylate alone or a blend of two or more thereof. A composition in which a polyolefin-based resin is added to the ethylene-based copolymer resin composition so that the content of the polyolefin-based resin is 1 to 50% by weight, wherein vinyl acetate, methyl methacrylate, ethyl acrylate or methyl A resin composition in which the content of two or more of acrylates or these monomers is 10% or more is heated and kneaded to form a sheet, and the sheet is made of a polyester, nylon, vinylon, Glass cloth type, aramid type, 1
100 to 2000 denier yarn is bonded and integrated on both sides of a coarse base fabric knitted at a length of 60 yarns / inch or less and a width of 60 yarns / inch or less to enhance welder adhesive strength. The polymer resin is ethylene vinyl acetate, and the polyolefin resin is polypropylene or high density polyethylene.

[0004]

DESCRIPTION OF THE PREFERRED EMBODIMENTS To explain an embodiment of the present invention, a polyolefin-based resin is added to an ethylene-based copolymer resin composition so that a specific polyolefin-based resin is 1 to 50% by weight, and vinyl acetate, Methyl methacrylate, ethyl acrylate or methyl acrylate or a resin composition having a content of two or more of these monomers of 10% or more is heated and kneaded to form a sheet. It is to be joined and integrated on both sides.

[0005] The ethylene-based copolymer resin composition comprises ethylene vinyl acetate, ethylene methyl methacrylate,
Ethylene ethyl acrylate or ethylene methyl acrylate alone or as a blend of two or more thereof. A polyolefin resin is contained in the ethylene copolymer resin composition such that the specific polyolefin resin is 1 to 50% by weight. Add resin. The ethylene copolymer resin composition to which the polyolefin resin is added is a resin composition in which the content of vinyl acetate, methyl methacrylate, ethyl acrylate or methyl acrylate, or two or more of these monomers is 10% or more. .

Examples of the polyolefin resin used in the present invention include polymers such as polyethylene, polypropylene, butene-butene-1,3-methyl-butene-1, hexene-1, octene-1,4-methyl-pentene-1 and the like. And high-density polyethylene, medium- and low-density polyethylene, ultra-low-density polyethylene, crystalline polypropylene, polybutene, and other polyolefin resins composed of a mixture thereof.

These resin compositions contain an antistatic agent, an ultraviolet absorber, an antioxidant,
Pigments, lubricants, and antiblocking agents can be added as appropriate.

According to the present invention, the above resin composition is heated and kneaded to form a sheet, and this sheet is more specifically formed into a sheet extruded by an extruder equipped with a T-die or a calender roll. The melt-rolled sheet is
100-2000 denier yarns are joined and integrated on both sides of a coarse base fabric woven at a length of 60 yarns / inch or less and a width of 60 yarns / inch or less. As a joining method, for example, the base fabric can be directly joined to a heated sheet extruded from a T-die or rolled by a calender roll. Alternatively, the cooled and solidified sheet and the base fabric can be joined together. It can also be laminated with a laminating machine. It is also possible to coat a coarse base cloth with an appropriate adhesive and laminate the base cloth.

In addition, the strength of the tarpaulin is determined not only by the strength of the polyolefin resin layer but also by the adhesive strength between the olefin resin layer and the coarse base cloth. However, a specific polyolefin resin is added to the ethylene copolymer. It is not clear that the olefin-based tarpaulin improves the welder strength at high temperatures, but by adding a specific polyolefin-based resin to the ethylene-based copolymer, it is possible to increase the By lowering the viscoelasticity at the time of melting of the coalesced, the pressure at the time of bonding the base cloth, the base cloth is put into the resin, and the resin is sufficiently squeezed into the thread of the base cloth, and the resin layer and It is considered that a laminated product having high strength is obtained by integrating the coarse base fabric layer.

The amount of the polyolefin resin to be added is such that the polyolefin resin is from 1% by weight to 50% by weight.
If the amount is more than 10% by weight, the compatibility is reduced.
% By weight.

The reason why the coarse base fabric is used is that stronger strength can be obtained by bonding the olefin resin layers on both sides to each other through the rough surface interval. In this case, it is preferable to use a knitted woven fabric in which 100 to 2,000 denier yarns are woven at a length of 60 yarns / inch or less and a width of 60 yarns / inch or less.

If the thickness of the resin layer is 0.05 mm, the resin layer can be joined to the base cloth, but preferably 0.2 mm or more from the viewpoint of strength. The material of the thread is polyester,
Nylon type, vinylon type, glass cloth type, and aramid type. Further, if the content of vinyl acetate, methyl methacrylate, ethyl acrylate, methyl acrylate, or two or more of these monomers is less than 10%, the welder adhesion becomes poor, preferably 12%.
The above is good.

Next, specific examples and comparative examples of the present invention will be described. The resin composition shown in Table 1 was melt-extruded with an extruder having a T-die of 40 mm to form a 0.25 mm sheet, and 20 sheets of 750 denier polyester fiber were punched into the sheet, both vertically and horizontally, per inch. 0.25 m extruded from the T-die again so as to sandwich the base cloth
m to form a laminated sheet. After bonding these laminated sheets to each other to a width of 3 cm with a welder, they are punched into strips of 3 cm width and used as a sample for a heat resistance test. A load of 15 kg is applied under an environment of 50 ° C., and the time until destruction is confirmed. Heat resistance test. The results are as shown in the table.

[0014]

[Table 1]

According to the present invention, ethylene vinyl acetate, ethylene methyl methacrylate, ethylene ethyl acrylate,
Or a composition obtained by adding a polyolefin resin to an ethylene copolymer resin composition comprising ethylene methyl acrylate alone or a blend of two or more thereof, so that the polyolefin resin is 1 to 50% by weight;
In this composition, the content of vinyl acetate, methyl methacrylate, ethyl acrylate or methyl acrylate or a content of two or more of these monomers is 10% or less.
% Or more of the resin composition is heated and kneaded to form a sheet,
The sheet, the material of the yarn is polyester, nylon,
Vinylon, glass cloth, aramid, 100-
By joining and integrating 2,000 denier yarns on both sides of a coarse base fabric woven at a length of 60 threads / inch or less and a width of 60 threads / inch or less, it is possible to provide a material having high welder adhesion strength and excellent heat resistance. it can. Therefore, even if a container which has been welded using this tarpaulin is filled with a high-temperature resin and a load is applied, the welder portion does not break and there is no danger of bag breakage.

Continuation of the front page (56) References JP-A-52-142785 (JP, A) JP-A-50-158383 (JP, A) JP-A-49-85141 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) B32B 1/00-35/00 D06N 1/00-7/06

Claims (2)

(57) [Claims] 1. An ethylene vinyl acetate, ethylene methyl methacrylate, ethylene ethyl acrylate,
Or a composition obtained by adding a polyolefin resin to an ethylene copolymer resin composition comprising ethylene methyl acrylate alone or a blend of two or more thereof, such that the polyolefin resin is 1 to 50% by weight;
In this composition, the content of vinyl acetate, methyl methacrylate, ethyl acrylate or methyl acrylate or a content of two or more of these monomers is 10% or less.
% Or more of the resin composition is heated and kneaded to form a sheet,
The sheet, the material of the yarn is polyester, nylon,
Vinylon, glass cloth, aramid, 100-
A method for producing an olefin-based tarpaulin, wherein 2000 denier yarns are joined and integrated on both sides of a coarse base fabric knitted at a length of 60 yarns / inch or less and a width of 60 yarns / inch or less to increase welder adhesive strength. 2. A method for producing an olefin-based tarpaulin, wherein the ethylene-based copolymer resin according to claim 1 is ethylene vinyl acetate, and the polyolefin-based resin is polypropylene or high-density polyethylene.