JPS58110242A - Laminate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention relates to a novel laminate. Conventionally, in order to take advantage of the characteristics of various materials, there has been active research into composite laminates made of different materials to meet various required physical properties. is being carried out. There are sometimes strict requirements for food packaging materials, such as hygiene, moisture resistance, gas resistance, UV resistance, water resistance, chemical resistance, oil resistance, cold resistance, heat resistance, and aging resistance. Various functions are required depending on the purpose, such as flexibility, processing resistance, thermal adhesion, thermoformability, transparency, colorability, printability, flavor retention, strength, cost, and flexibility. .

These various demands? Since it is difficult to meet the requirements using the same material, it has become common to use a small layer of bebe material even in prize packaging materials. Methods for obtaining these laminates can be roughly divided into methods using an adhesive and methods using heat seal lamination, Ectrouge 1-N Lamination-7117, etc. without using an adhesive. Although the latter method is industrially useful, the former method currently predominates because there are restrictions on the combination of materials.

Conventional adhesives used in food packaging laminates include ld and polyurethane resins. Although polyurethane resins exhibit excellent adhesion performance, some problems remain, such as the possibility of transfer of low molecular weight compounds to foods and the need for aging after adhesion. For this reason polyurethane.

Carboxyl group-containing polyolefin resins are now being used in place of polyolefin resins. This modified polyolefin itself is a useful material because it has few problems in terms of hygiene and at the same time has good adhesion to polyolefin resins, aluminum foil, and the like.

However, these modified polyolefins include polyethylene terephthalate (PET), polyvinylidene chloride, poval, nylon, and hydrolysates of ethylene-vinyl acetate copolymers, which are commonly used as materials for plastic wrappers for packaging perforated products. However, there remained the problem that the adhesion to the material was low, and there were still restrictions on the combinations of materials.

The inventors of the present invention were made aware of the current situation as described above, and as a result of intensive research,
A plastic base material (A) and a polyolefin (B) containing a carboxyl group-containing polyolefin are mixed with a thin mixed layer (C ), the adhesive strength is sufficient for practical use, and even when used as a packaging material for retort pouches, the laminate has no practical problems in adhesive strength after retort. The samurai discovered this and completed the present invention.

Examples of the plastic base material (A) in the second invention include polyester, nylon, polyvinylidene,
Polyvinyl weir, poval, saponified ethylene-vinyl acetate co-electrolyte, polycarbonate, polystyrene, acrylic resin, epoxy resin, urethane resin, cellophane,
Modified polyolefin resins are available, and the surface of these base materials may be untreated, but physical surface treatments such as sandblasting, chemical treatments such as corona discharge or primer coating may be applied to improve the strength. It may also be one that has undergone surface treatment.

The metals and metal oxides used in the present invention include:
There are no particular restrictions as long as it is stable in air. For example, metals include A2, Zn, Sb, nX CdXA
gX Au, Or.

Si, Co, Zr, Sn, Fe, C! u, Ni.

Pt, Pd, Bi, Mg, TiXMn, Mo.

■ etc., and if it is 1, n-radical oxides can be mentioned, but it is limited to economic efficiency and use as prize packaging material.
For example, it is preferable to use SnX Ag, AJ, 203, Mgo, or the like.

The mixing ratio of these metals or metal oxides and tin oxide may be within a fairly wide range; for example, 10,000:1 to 1:10,000 contributes to adhesion, but 100:1 to 1:1: 1
It is preferably within about 00. Furthermore, it may be necessary to reduce the amount of metal in order to obtain a transparent laminate.

The thickness of the mixture thin layer <C> is preferably from a monomolecular layer to about 1,000A'; if it is too thick, no improvement in the effect can be expected. Usually, a thickness of several molecular layers to 5-500A@゛・ is sufficient. The thin mixture layer (C) is preferably formed on the plastic substrate (A) by vacuum deposition or vapor deposition such as block sputtering.

The carboxyl group-containing polyolefin used in the present invention is composed of olefinic monomers such as ethylene, propylene, butene, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, maleic anhydride, and α,β-amino acids. Akuorocarponba, and other (meth)acrylics ('
It is a copolymerized or grafted product of I ester, etc., and the amount of α, β-unsaturated) [1 carboxylic acid is preferably 0.01 to 30 parts by weight per 100 parts of the olefin component.

If it is too small, the effect on adhesion will be weak, and if it is too large, no improvement in the effect will be observed, resulting in poor alkaline water resistance. These carboxyl group-containing polyolefins may be used alone, or may be mixed with unmodified polyethylene, polypropylene, etc., and furthermore, metal compounds generally called 6-ionomers may be added. Metal compounds include modified products of sodium, potassium, zinc, iron, aluminum, copper, nickel, etc., hydroxides, carbonates, acetates, sulfates, etc., based on 100 parts by weight of carboxyl group-containing polyolefin. It can be blended up to about 20 parts by weight.

Further, the content of the qualitative polyolefin is preferably 5% by weight or more based on the unmodified polyolefin, since filtration is effective for adhesion.

A specific method for manufacturing the laminate according to the present invention is to form a thin layer (C) of the mixture on a plastic substrate (A) by e-evaporation, and then apply a thin layer of polyolefin (B) on top of this by e-evaporation. It is preferable to carry out extreme lamination or to form a polyolefin (B) film and to laminate it under heat and pressure. It is possible to further improve the adhesion of the polyolefin (B) film by subjecting it to corona discharge treatment.

The laminate according to the present invention includes 'y'J, P E'T / mixture thin layer / carboxyl group-containing polyolefin (hereinafter sometimes abbreviated as modified PO), pE'r, ' mixture thin layer / modified PO/polyolefin (hereinafter sometimes abbreviated as po), pgT/mixture thin layer/mixture of modified PO and PO, or nylon instead of PET can be used as a transparent packaging material, and is gas impermeable. sex,
If moisture-proof function is required, PET
(or nylon) / adhesive / Poval (and or saponified ethylene vinyl acetate copolymer, polyvinylidene chloride) / thin layer of mixture / modified PO (PO), PET (
or nylon)/mixture thin layer/modified po/A
It can be combined with other materials depending on the purpose, such as Q foil/modified po/(po), and has extremely high utility value as a composite material, and is used for a wide range of purposes. .

Example 1゜Metal aluminum and tin oxide were deposited on a biaxially stretched polyester film (12μ).The aluminum content in the film was 5'.
The base material was evaporated to about 300A' while adjusting the N content%, and a film (40μ) of maleated kraft polypropylene was deposited at 2000C and a linear pressure of 5 K'g/cm.
A laminate was obtained by pressure bonding. This term, beak adhesive strength k
15 mm Width: 1.5 as measured by T-type stripping method
K g/15 mm or more"t'f)0.

Furthermore, 50mJ of water can be stored in a 10100x150 bag made from this laminate! After boiling (retort treatment) in a high-pressure oven for 121°0130 minutes, the adhesive strength of the laminate k
15 mm width 500 g as measured by T-type peeling method
, /15 mm or more.

Example 2 Table 1 was used in place of the polyester film in Example 11C.
A similar test was conducted using the plastic substrate shown in . The peel strength was as shown in Table 1.

-〇- Table 1 Actual 7iii Example 3 In a certain excitation color 11, each of the following, ・f, as shown in Table 2, was used instead of the total aluminum that was choreographed to be vapor-deposited with monotin.
A similar test was carried out using Imaka, Kinsha, and Misaki Panazu. The results are shown in Figure 2.

2 When a corona discharge treated polypropylene film was used in place of the maleic acid kraft polypropylene film in Example 1, no adhesion occurred.

Comparative Example 2 When the same test as in Example 1 was carried out by depositing only tin oxide without any aluminum mixing, the contact frequency of the laminate before and after retort treatment was 1.54/l.
5 g714 width or more and 0.11 (p/15 word width).

Example 3 In Example 1, the vapor deposition thickness was set to 200 A0, and then an ionomer resin (Himilan, a product name manufactured by Mitsui Polychemical Networks) was laminated with Ectoriegin to a thickness of about 30 μm, and the peel strength was 1. .2 K? ,/
The peel strength after this retort treatment was 0.5 Kα/l 511' width.

Example 4 A test was conducted in the same manner as in Example 1 except that the surface of the polyester film to be deposited was subjected to corona discharge treatment in advance.
Even after retorting, the peel strength was 10/15.

patent applicant Toyo Ink Manufacturing Co., Ltd. 13-

Claims (1)

[Scope of Claims] 1. A plastic base material (A) and a polyolefin (B) containing a carboxyl group-containing polyolefin are combined with tin oxide and a metal oxide and/or a metal oxide.
Excludes tin oxide. ) through a thin layer of mixture (C). 2 A thin mixture of tin oxide and metal and/or a cap (excluding tin oxide) on the surface (C) Fully formed plastic base material ( A)
The laminate according to claim 1, characterized in that f is used.