JPH04259547A - Composite film for deep-drawn molding - Google Patents

Abstract

PURPOSE:To obtain composite film for deep-drawn molding which can be used for steam shrink-type wrapping and has an exceedingly good appearance. CONSTITUTION:The composite film consists of a nylon outer layer 6, a polyolefin inner layer and an intermediate layer of nylon 6 or nylon 6/66 between both layers through an adhesive layer in a laminated formation. In addition, the nylon outer layer 6 is thinner than the intermediate layer, and the total thickness of the outer layer and the intermediate layer ranges from 30 to 100mum as a composite film. This composite film consisting of a combination of the nylon 6 layer (outer layer) and the nylon 6 or nylon 6/66 intermediate layer, is molded satisfactorily and makes a wrapped product with an extremely good appearance.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a composite film, which
In particular, after filling a bottom material container obtained by deep drawing with irregularly shaped processed meat products such as handmade ham, water vapor is blown from the outside to shrink the bottom material container to improve its adhesion to the filled contents. The present invention relates to a composite film for deep drawing that can be suitably used in a so-called steam shrink type packaging method that can be improved.

0002

[Prior Art and its Problems] The bottom material used in the above-mentioned steam shrink type packaging method includes composite films of various compositions, for example, those made of polyolefin/gas barrier resin/polyolefin using polyolefin resin for the inner and outer layers. It is used. However, depending on the resin used, there are problems in terms of appearance, such as deterioration of gloss due to spraying of water vapor or whitening of the sealing part of the lid material.

0003

[Means for Solving the Problems] The present invention has discovered a composite film for deep drawing that can be suitably used in steam shrink type packaging methods and has excellent appearance characteristics. The outer layer is a nylon 6 layer, the inner layer is a polyolefin layer, and an intermediate layer made of nylon 6 or nylon 6/66 is laminated between the two layers with an adhesive layer interposed therebetween, and the outer layer is a nylon 6 layer. The composite film for deep drawing is characterized in that the thickness of the composite film is equal to or less than the thickness of the intermediate layer, and the total thickness of the outer layer and the intermediate layer is in the range of 30 to 100 μm.

The polyamide resin used for the intermediate layer of the composite film of the present invention includes nylon 6 or nylon 6/66.
need to be used. 66 as nylon 6/66
A copolymer having a component content of 15 to 20 mol % can be suitably used. By using nylon 6 or nylon 6/66 for the intermediate layer, the film strength such as pinhole resistance can be improved, and the film and label can be easily bonded during boil sterilization, especially in systems where labels are attached and boil sterilized after steam shrinking. It has the advantage of preventing wrinkles. The thickness of the intermediate layer is preferably in the range of about 30 to 60 μm.

[0005] Furthermore, it is necessary to use nylon 6 for the outer layer, which has the effect of imparting gloss to the film surface, preventing moist heat blocking and whitening of the sealing portion of the lid material. The thickness of the outer layer made of nylon 6 must be less than or equal to the thickness of the intermediate layer, and the total thickness of the outer layer and the intermediate layer must be in the range of 30 to 100 μm. If the thickness of the outer layer exceeds 1/2 of the thickness of the intermediate layer, the formability during deep drawing will be poor, and the total thickness of the outer layer and the intermediate layer will be 30%.
If it is less than 10 μm, pinholes are likely to occur in the film.
If the thickness exceeds 0 μm, there is a problem that the film itself becomes too hard and difficult to handle. The thickness of the outer layer is 15-40μ
A range of about m is preferable.

Furthermore, the inner layer (sealing material layer) is a layer of polyolefin, and the polyolefin resin includes low density polyethylene, linear low density polyethylene, and ethylene-
Vinyl acetate copolymers, particularly those with a vinyl acetate content in the range of 3 to 8 mol %, are preferred because they have good sealing properties and the lid material is difficult to peel off during boil sterilization. The thickness range of the inner layer is 50-1
A material having a diameter of about 0.00 μm can be suitably used. An adhesive layer such as carboxylic acid-modified polyolefin is interposed between each of the resin layers mentioned above to improve the adhesion between the layers, but the adhesive layer on the inner layer (sealant layer) side may be omitted depending on the resin used for the inner layer. It is also possible to do so.

[0007] Here, since the above-mentioned outer layer of nylon 6 tends to be easily affected by water vapor, the water repellency can be improved by overcoating the outer layer surface with a surface coating agent, such as a nitrified cotton-based material, if necessary. After steam shrink packaging,
It has the advantage that the label is difficult to peel off during the labeling process. For water repellency, the contact angle with distilled water should be in the range of about 70° to 105°; if the contact angle is less than 70°, water will not be repelled properly and water will be interposed between the film and the label, resulting in decreased adhesion. Moreover, if the angle exceeds 105°, there is a problem that the adhesiveness decreases regardless of the presence or absence of water.

[0008]

[Effects of the Invention] The composite film of the present invention can be used in a steam shrink type packaging method to provide a packaged product with excellent appearance, and is extremely useful as a packaging material for irregularly shaped processed meat products such as handmade ham.

Claims (1)

[Claims] Claim 1: The outer layer is a nylon 6 layer, the inner layer is a polyolefin layer, and an intermediate layer made of nylon 6 or nylon 6/66 is laminated between both layers with an adhesive layer interposed therebetween, and the outer layer is made of nylon. The thickness of layer 6 is less than or equal to the thickness of the intermediate layer, and the total thickness of the outer layer and the intermediate layer is 30 to 10
A composite film for deep drawing forming, characterized in that the thickness is in the range of 0 μm.