JPH0642686U - Multi-layer bag - Google Patents

Abstract

(57) [Summary] [Purpose] A multi-layer bag that combines an outer layer made of plastic composite paper and an inner layer made of paper for containing milling and feed. [Composition] A plastic composite paper made by laminating a biaxially oriented polypropylene film and paper is used as the outer surface and the inner surface as the film surface to form an outer layer as a tubular body. In a bag in which an inner layer of a tubular body made of paper is internally provided to fix both tubular bodies, and further, the upper and lower mouths or the lower mouths are provided with both bottoms or one bottom by a conventional method such as sewing with a sewing machine or pasting glue, A multi-layer bag in which the joint portion of the body of the outer layer is attached with an adhesive such as an adhesive.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a multilayer bag having a double structure for carrying cement, fertilizer, feed and the like.

[0002]

[Prior art]

 Recently, as a bag material, a composite paper made by laminating a plastic film and paper is widely used. For example, a material made by laminating a plastic film on one side of kraft paper, a material made by slitting and stretching a plastic film and using woven fabric as a woven stretchable paper, such as so-called plastic composite paper. Since the bag has many features as compared to a simple paper bag due to its self-supporting property, high strength, elongation and suitability for bag making, its use is expanding year by year.

[0003]

[Problems to be solved by the device]

 However, among these composite materials, the material in which the stretched film is adhered to the paper has a large strength such as the strength and moisture resistance of the bag main body corresponding to 2 to 3 layers of kraft paper. For example, in the case of making heavy-duty bags for industrial use, when using a material in which biaxially stretched polypropylene film is attached to kraft paper, the shaping of the body of the bag is done by joining the kraft paper 1 The end portion is made longer than the end portion of the biaxially stretched polypropylene film 2 to form the kraft paper adhesive portion 3 (see FIG. 1), and is made into a bag shape by contacting with the film surface of the inner joint portion. In heat welding, the melting temperature range is small, which makes it difficult to control the temperature, and the strength is extremely weak even after heat welding. A shock is applied to the joint part of the body Barrel the like according becomes defective portion, breakage, a phenomenon such as peeling occurs. Therefore, there were various defects such as the phenomenon that the strength of the bag body and the body was extremely unbalanced, and the strength, which is the characteristic of the plastic composite paper, could not be fully exhibited. The present invention relates to a completely new technology for industrial heavy packaging bags developed in view of these problems in the past.

[0004]

[Means for solving the problem]

 The present invention was devised to solve the above-mentioned deficiencies. It uses a material made of a plastic composite paper that is a composite of biaxially oriented polypropylene film and paper. The outer layer has a paper surface on the outside and the film surface on the inside. This relates to a multi-layer bag having a double structure formed by combining inner layers made of kraft paper inside.

[0005]

EXAMPLES Now, an example of the implementation will be described in detail with reference to the drawings. FIG. 1 is an explanatory view of a splicing part of a body part when a plastic composite paper, which has been widely used in the past, is formed into a bag, and FIG. 2 is a lateral cross-sectional enlarged view of the plastic composite paper used in the present invention. Then, a biaxially stretched polypropylene film 5 is polymerized on a paper 4 such as kraft paper or stretchable paper and bonded with an adhesive 6. FIG. 3 is an enlarged cross-sectional view in the lateral direction of the kraft paper 7 or the like which forms an inner bag to be contained inside when the composite paper shown in FIG. 2 is used as an outer layer. An outer layer 8 is a tubular body made of plastic composite paper and having the paper 4 as an outer side, and an inner layer 9 of the tubular body made of kraft paper having almost the same size as the tubular body is internally provided inside the tubular body. Of the outer layer 8 of the outer layer 8 in a multilayer bag in which both bottoms or one bottom are provided by fixing the tubular body of The seamed portion is pasted with an adhesive 11 such as an adhesive adhesive to form a bag.

[0006]

[Effect of device]

 Therefore, in the present invention, the biaxially oriented polypropylene film is stuck inside the outer layer, and the joint part of the body is pasted with an adhesive such as an adhesive adhesive. Since the inner layer is contained inside the outer layer, the edge of the kraft paper, which is inside the spliced portion of the body that has been widely used in the past, is made longer than the edge of the film to form the kraft paper bond. However, in the bag-making industry, paper is paper, and film is the seam of the body part that sticks to the paper.In the case of so-called ear-sliding, it absorbs moisture from the gap between the paper and the film and has a perfect moisture-proof effect. However, in the present invention, since the biaxially stretched polypropylene film adhered to the inside of the outer layer is adhered with the adhesive adhesive of the same structure in the present invention, Film surface and adhesive DOO is more of also allowed to increase the 且防 humidity effect preventing deterioration in strength as well as preventing the combination phenomenon such as peeling. Further, since the inner layer is interposed inside the outer layer, the contents are not directly adhered to the biaxially stretched polypropylene film surface stuck to the inner side of the outer layer, so that the film surface is not weakened. . Furthermore, a biaxially oriented polypropylene film is interposed between the outer layer and the inner layer to form a three-layer structure, and the strength of the spliced part of the outer layer of the outer layer is increased. It is remarkably superior to the one using the plastic composite paper, and the filling work is easily performed. Therefore, it is possible to completely prevent the contents from leaking, and to provide a multi-ply bag of great practical value, which has many effects such as not breaking the bag during handling and storage of the bag. .

[0007]

[Brief description of drawings]

FIG. 1 is an explanatory view of a spliced part of a body part when a plastic composite paper, which has been widely used in the past, is formed into a bag as a single layer.

FIG. 2 is an enlarged cross sectional view of a plastic composite paper used in the present invention.

FIG. 3 is an enlarged lateral cross-sectional view of a paper that forms an inner layer to be included inside when the composite paper shown in FIG. 2 is used as an outer layer.

FIG. 4 is a plan view of the plastic composite paper according to the present invention.

5 is an enlarged cross-sectional view taken along line AA of FIG.

[Explanation of symbols] 1 is kraft paper 10 is crepe paper 2 is biaxially oriented polypropylene 11 is adhesive adhesive Pyrene film 3 is kraft paper adhesive 4 is paper 5 is biaxially oriented polypropylene film 6 is adhesive 7 Paper 8 is outer layer 9 is inner layer

Claims (1)

[Scope of utility model registration request] 1. A plastic composite paper obtained by laminating a biaxially oriented polypropylene film and paper with an adhesive, with an outer surface being the paper surface and an inner surface being the film surface in an outer layer which is a tubular body, and the inside of which is the cylinder. The inner layer of a tubular body made of kraft paper of almost the same size as that of the tubular body is provided internally, and both tubular bodies are fixed to each other. A multi-layered bag having a single-bottomed bag, wherein the spliced portion of the body of the outer layer is laminated with an adhesive such as an adhesive.