JPH05104683A - Manufacture of olefin-based trapaulin - Google Patents

Abstract

PURPOSE:To provide olefin-based tarpaulin, which has strong welder bonded strength at elevated temperature without impairing safety. CONSTITUTION:Composition prepared by adding 1-50 pts.wt. of polyolefin-based resin to ethylene-based copolymer resin composition, which is made of single ethylene vinyl acetate, ethylene methyl methacrylate, ethylene ethyl acrylate or ethylene methyl acrylate or lbende of two or more different above-mentioned substances. The resin composition having the content of vinyl acetate, methyl methacrylate, ethyl acrylate or methyl acrylate or the sum of two or more different monomers just mentioned above of 10% or more, is kneaded under heat into the form of sheet so as to integrally join the resultant sheet onto both the sides of wide-meshed ground fabric woven by threads having the finess of 100-2,000 denier under the condition that the mesh of warp of 60 thread/inch or less and that of woof of 60 thread/inch or less in order to produce the tarpaulin concerned.

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-based copolymer having excellent heat resistance, and more specifically, it is prepared by adding a specific polyolefin-based resin to a specific ethylene-based copolymer and heating it. The present invention relates to a method for producing an olefin-based tarpaulin, which is obtained by joining and kneading sheets obtained by kneading on both sides of a coarse base cloth.

[0002]

2. Description of the Related Art A typical tarpaulin of an ethylene-based copolymer is a sheet of ethylene vinyl acetate (EVA) which is joined and integrated on both sides of a base cloth. Such a material also has good cold resistance at low temperatures, has no plasticizer as compared with polyvinyl chloride (PVC) tarpaulins, and is excellent in safety without elution of liquid components. However, problems were often pointed out regarding the strength at high temperature due to the characteristics of the material. In particular, there are many problems with respect to the strength of the welder adhesion part, and when filling a high temperature material (for example, resin) into the tarpaulin, there is a problem that the self-weight of the resin breaks the bag. The present inventors have conducted extensive studies to provide a olefin copolymer tarpaulin having a high welder adhesive strength at high temperature without impairing safety, and as a result, a specific polyolefin resin was added to the ethylene copolymer. The present invention has been completed by the addition.

[0003]

[Means for Solving the Problems] Means taken by the present invention to solve the above problems are as follows: ethylene vinyl acetate, ethylene methyl methacrylate, ethylene ethyl acrylate, or ethylene methyl acrylate, or a mixture of two or more thereof. A composition obtained by adding 1 to 50 parts by weight of a polyolefin resin to an ethylene-based copolymer resin composition obtained by the method, wherein vinyl acetate, methyl methacrylate, ethyl acrylate or methyl acrylate or a monomer thereof is used in the composition. Of two or more types of the resin composition having a content of 10% or more are kneaded by heating to form a sheet,
A 0 denier yarn is bonded and integrated on both sides of a coarse base fabric knitted with 60 warps / inch or less and 60 wefts / inch or less, and the ethylene-based copolymer resin is ethylene vinyl acetate. That is, the polyolefin resin is polypropylene or high density polyethylene.

[0004]

EXAMPLES To explain one example of the present invention, 1 to 50 parts by weight of a specific polyolefin resin is added to an ethylene copolymer resin composition, and vinyl acetate, methyl methacrylate, ethyl acrylate or methyl A resin composition containing 10% or more of acrylate or two or more of these monomers is kneaded by heating to form a sheet, and the sheet is joined and integrated on both sides of a coarse base cloth. Is.

The ethylene-based copolymer resin composition includes ethylene vinyl acetate, ethylene methyl methacrylate,
It is made of ethylene ethyl acrylate or ethylene methyl acrylate alone or a blend of two or more kinds thereof, and 1 to 50 parts by weight of a specific polyolefin resin is added to the ethylene copolymer resin composition. The ethylene copolymer resin composition to which the polyolefin resin is added is a vinyl acetate, methyl methacrylate, ethyl acrylate or methyl acrylate or a resin composition containing 10% or more of two or more of these monomers. ..

The polyolefin resin used in the present invention is a polymer such as polyethylene, polypropylene, butene butene-1,3-methyl-butene-1, hexene-1, octene-1,4-methyl-pentene-1. And a polymer mainly composed of a copolymer, which is a high density polyethylene, a medium low density polyethylene, an ultra low density polyethylene, a crystalline polypropylene, a polybutene, or another polyolefin resin composed of a mixture thereof.

These resin compositions include antistatic agents, ultraviolet absorbers, antioxidants, which are well known in the technical field of this type,
A pigment, a lubricant, and an antiblocking agent can be added as appropriate.

In the present invention, the above resin composition is kneaded by heating to form a sheet, and more specifically, the sheet is melt-extruded by an extruder equipped with a T-type die or a calendar roll. Melt rolled sheet,
A 100 to 2000 denier yarn is bonded and integrated on both sides of a coarse base fabric knitted with 60 warps / inch or less and 60 wefts / inch or less. As a joining method, for example, it is possible to directly join the base fabric to a heated sheet extruded from a T-die or rolled by a calender roll, or to cool and solidify the sheet and the base fabric. It can also be laminated with a laminating machine. It is also possible to coat the rough base cloth with an appropriate adhesive and laminate it.

Regarding the strength as a tarpaulin, the strength of the polyolefin resin layer and the adhesive strength between the olefin resin layer and the rough base cloth are problems at the same time. However, a specific polyolefin resin is added to the ethylene copolymer. Therefore, it is not clear that the welder strength of olefinic tarpaulin at high temperature is improved.However, by adding a specific polyolefin resin to the ethylene copolymer, the olefin copolymer Due to the decrease in viscoelasticity of the coalesced material when melted, the base cloth is sufficiently sunk into the resin and the resin is sufficiently squeezed into the threads of the base cloth due to the pressure applied when the base cloth is attached. It is considered that a laminate having a high strength is obtained by integrating the coarse base fabric layer.

The addition amount of the polyolefin resin is 1
The amount is from 50 parts by weight to 50 parts by weight, and if it is less than 1 part by weight, the heat resistance is not effective, and if it exceeds 50 parts by weight, the compatibility is lowered, preferably 3 to 20 parts by weight.

The reason why the rough base cloth is used is that the olefin resin layers on both sides are bonded to each other through the rough surface intervals, whereby stronger strength can be obtained. In this case, it is preferable to use, as the base fabric, a knitted fabric in which 100 to 2000 denier yarns are knitted at a length of 60 threads / inch or less and a weft of 60 threads / inch or less.

If the thickness of the resin layer is 0.05 mm, it can be joined to the base cloth, but it is preferably 0.2 mm or more in terms of strength. Also, as the material of the thread, polyester type,
Nylon type, vinylon type, glass cloth type and aramid type are listed. 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 will be 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 by an extruder with a T-die of 40φ mm to form a sheet of 0.25 mm, and 750 denier polyester fiber was punched into this sheet with 20 lengths and 20 widths per inch. After the base fabric is laminated at the same time, it is laminated again with the 0.25 mm sheet extruded from the T-type die so as to sandwich the base fabric to form a laminated sheet. After laminating the laminated sheets with a width of 3 cm with a welder, 3
A sample with a width of cm was punched out and used as a sample for heat resistance test.
A load of 15 kg was applied under an environment of 0 ° C., and a heat resistance test was performed to confirm the time until destruction. The results are shown in the table.

[0014]

[Table 1]

[Effect] The present invention applies ethylene vinyl acetate, ethylene methyl methacrylate, ethylene ethyl acrylate,
Alternatively, a composition obtained by adding 1 to 50 parts by weight of a polyolefin resin to an ethylene copolymer resin composition which is a mixture of ethylene methyl acrylate alone or two or more kinds thereof, and vinyl acetate in the composition, A resin composition containing 10% or more of methyl methacrylate, ethyl acrylate, or methyl acrylate, or two or more of these monomers is kneaded by heating to form a sheet, and the sheet is formed into a yarn of 100 to 2000 denier. It is possible to provide a product having a high welder adhesive strength and excellent heat resistance by integrally bonding to both sides of a rough base fabric knitted and woven at 60 vertical lines / inch or less and 60 horizontal lines / inch or less. Therefore, even if a container that has been welded using this tarpaulin is filled with high temperature resin and a load is applied, the welder does not break and there is no risk of bag breakage.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location C08L 23/08 LDJ 7107-4J

Claims (2)

[Claims] 1. Ethylene vinyl acetate, ethylene methyl methacrylate, ethylene ethyl acrylate,
Alternatively, a composition obtained by adding 1 to 50 parts by weight of a polyolefin resin to an ethylene copolymer resin composition which is a mixture of ethylene methyl acrylate alone or two or more kinds thereof, and vinyl acetate in the composition, A resin composition containing 10% or more of methyl methacrylate, ethyl acrylate, or methyl acrylate, or two or more of these monomers is kneaded by heating to form a sheet, and the sheet is formed into a yarn of 100 to 2000 denier. The method for producing an olefinic tarpaulin is characterized in that the woven tarpaulin is bonded and integrated on both sides of a coarse base fabric knitted at a length of 60 pieces / inch or less and a width of 60 pieces / inch or less. 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.