JPH0337944Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Technical Field] The present invention relates to a composite sheet that can be easily thermoformed and used as a material for bags, bags, and the like. [Prior art and its problems] Bags, bags, etc. are generally composed of three elements: an exterior material, a core material, and an interior material. Sometimes the core material also serves as the interior material, but in this case it has a two-element configuration. Natural leather, artificial leather, synthetic leather, etc. are used as the exterior material, plastic sheets, cardboard, etc. are used as the core material, and woven fabrics are often used as the interior material. These components are separate at the material stage, but are integrated through sewing and other processes during the finishing process of bags, bags, and other products. Products such as bags and bags are made by sewing, so when molding a three-dimensional shape such as a box, a seam must be placed at each corner, which requires a lot of man-hours. It has the disadvantage of requiring Another problem is that it is difficult to create complex shapes such as unevenness, which limits the design. [Means for solving the problems and their effects] In view of the problems of the prior art as described above, the present invention provides an easy-to-form composite sheet that integrates the constituent materials of bags, bags, etc. The structure consists of a cross-linked polyolefin foam sheet with an elongation rate of 100% or more in both the vertical and horizontal directions, and one side of which is laminated with synthetic leather based on woven fabric, which also has an elongation rate of 100% or more in both the vertical and horizontal directions. It is characterized by the fact that The basic structure of the composite sheet according to the present invention is illustrated in FIG. 1. That is, this composite sheet 1 is made by laminating a synthetic leather 5 consisting of a woven fabric 3 and a synthetic leather skin 4 on one side of a crosslinked polyolefin foam sheet 2.
Both of the synthetic leathers 5 and 5 have elongation rates of 100% or more in both the longitudinal and lateral directions. As shown in FIG. 2, the composite sheet of the present invention preferably has a woven fabric 6 laminated on the surface of the crosslinked polyolefin foam sheet 2 opposite to the synthetic leather 5. This woven fabric 6 also has the property of having an elongation rate of 100% or more in both the longitudinal and transverse directions. More preferably, in the composite sheet 1 as shown in FIG. 2, the tensile strength of the woven fabric 6 is greater than that of the synthetic leather 5. Such a composite sheet can be easily formed into a desired shape by thermoforming such as vacuum forming, and can be easily processed into bags, bags, and the like. The material of the crosslinked polyolefin foam sheet 2 is polyethylene, polypropylene, ethylene-
Vinyl acetate copolymer or the like is preferable. The crosslinking method includes a chemical crosslinking method and an electron beam crosslinking method, and either of them may be used, but a foam sheet using the chemical crosslinking method is more desirable. Further, the expansion ratio is in the range of 2 to 40 times, and most preferably in the range of 5 to 20 times. The thickness ranges from 2 to 15 mm, most preferably from 4 to 10 mm. The reason for using a crosslinked polyolefin foam sheet is that it has superior thermoformability compared to non-crosslinked products. It is also for the same reason that the above-mentioned materials and crosslinking methods are desirable. The reason why the expansion ratio and thickness are set within the above range is to exhibit more appropriate properties from the viewpoint of shape retention properties as a core material. Next, regarding the woven fabric 3 that constitutes the base fabric of the synthetic leather 5 and the woven fabric 6 that is laminated on the back side of the foam sheet 2, among the forms of fabrics such as paper, nonwoven fabric, and woven fabric, woven fabric is Refers to the form. Also, woven fabrics include woven fabrics and knitted fabrics, and although either one is acceptable, knitted fabrics are more desirable. The material of the woven fabric is
Natural fibers, synthetic fibers, or blended fibers thereof. Natural fibers include wool, cotton, linen, etc., and synthetic fibers include nylon, polyester, vinylon, acrylonitrile, etc. Further, the blended fiber may be a blend of natural fibers and synthetic fibers, a blend of nylon and polyester, a blend of wool and cotton, or a blend of synthetic fibers or natural fibers. Among these, it is preferable to use synthetic fibers, and it is preferable not to use blended fibers. Woven fabrics are used because they have a high elongation rate, which is necessary for thermoforming, and knitted fabrics have the best properties. Also, the reason why synthetic fibers are desirable is that they have excellent thermoforming processability, and the reason why it is better not to use blended fibers is because thermoforming conditions can be kept constant. Furthermore, the reason why it is desirable that the tensile strength of the woven fabric 6 is higher than that of the synthetic leather 5 is that during the thermoforming process, the synthetic leather 5 is formed on the outside, but at this time, the woven fabric 6 that is on the inside is This is because if the strength is high, the flat part of the finished product will curve slightly outward (the synthetic leather 5 side will swell slightly), improving the appearance of the bag or bag and increasing its commercial value. When the flat part curves inward,
It looks petty and doesn't give a good product image. Next, the outer skin 4 of the synthetic leather 5 includes all materials generally called synthetic leather, but polyurethane-based materials are particularly desirable. Although the thickness of the skin 4 is not particularly specified, it is preferably 20 to 100 μm. The reason for using the synthetic leather 5 is that it is suitable for thermoforming among exterior materials. Further, the reason why the elongation rate of each material constituting the composite sheet for molding is set to 100% or more in both the vertical and horizontal directions is as follows. The composite sheet of the present invention is mainly subjected to vacuum forming processing, and as shown in Fig. 3, the composite sheet 1 is surrounded by a frame 7.
After heating the composite sheet 1, a mold 8 is applied to the composite sheet 1, a vacuum is drawn between the mold 8 and the composite sheet 1, and the composite sheet 1 is adsorbed to the mold 8, thereby performing molding. Therefore, the material sheet is required to have a high elongation rate, and it is desirable that the material sheet can be elongated by at least twice as much in both the vertical and horizontal directions. An increase of more than 2 times is more than 100% in terms of growth rate. There are two methods for laminating each material: a method using heat fusion and a method using an adhesive; either method may be used. [Example] Table 1 shows Example 1 of the composite sheet according to the present invention.
The configurations of 4 to 4 and the results of thermoforming are shown below. Both are laminated using adhesive.

[Effect of idea]

As explained above, the composite sheet for molding of the present invention integrates the synthetic leather that serves as the exterior material and the crosslinked polyolefin foam sheet that serves as the core material.
By using this, a desired shape can be easily formed by thermoforming without sewing the corners, and the number of man-hours required for manufacturing bags, bags, etc. can be significantly reduced. It also has the advantage of being highly moldable, allowing for diversification of designs.

[Brief explanation of the drawing]

1 and 2 are cross-sectional views showing the structure of the composite sheet for molding according to the present invention, FIG. 3 is an explanatory diagram of the vacuum forming method, and FIGS. FIG. 2 is a cross-sectional view and a plan view of a molded product. 1...Composite sheet for molding, 2...Crosslinked polyolefin foam sheet, 3...Woven fabric, 4...Skin, 5
...Synthetic leather, 6...Woven fabric.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) On one side of a crosslinked polyolefin foam sheet with an elongation rate of 100% or more in both the longitudinal and transverse directions, a woven fabric with an elongation rate of 100% or more in both the longitudinal and transverse directions. A composite sheet for molding characterized by laminating synthetic leather as a base fabric. (2) In the composite sheet described in claim 1 of the utility model registration claim, the other side of the crosslinked polyolefin foam sheet has an elongation rate of 100 in both the vertical and horizontal directions.
% or more of woven fabric is laminated. (3) In the composite sheet described in claim 2 of the utility model registration, the woven fabric laminated on the other side of the crosslinked polyolefin foam sheet has a higher tensile strength than the synthetic leather laminated on one side. something with great strength.