JPS63254035A - Film for printed 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 Technical Field of the Invention The present invention relates to a novel print laminating film.

[Prior art and its problems]

Traditionally, it has been used to protect, preserve, and protect various paper products such as covers of publications such as magazines and books, printed materials such as posters and cards, paper containers such as various food containers, and even handbags. Plastic films that are highly water-resistant, oil-resistant, weather-resistant, etc. are used on the surface to maintain their aesthetic appearance, and these films are used to coat such printed materials and paper products (hereinafter simply referred to as printing paper, but also includes plain paper). Laminating is generally called print lamination or print lamination.

In the conventional print lamination method, a two-component adhesive made by dissolving an adhesive resin in an organic solvent is applied to a polypropylene film, this is dried to scatter the organic solvent, and then this adhesive-coated surface is printed. This is done by thermo-compression bonding with paper.

However, when using adhesives in which organic solvents have been dissolved in this way, it requires a lot of processing during work, and there is a risk of fire as well as the problem of air pollution due to the scattering of the organic solvent gas or the problem of the gas. There were occupational health problems due to inhalation of the substances into the body.

In addition, the resulting product had problems such as low adhesive strength, poor solvent resistance, and the presence of fumes.

Therefore, in recent years, methods of print lamination without using such organic solvents have been proposed. For example, films have been developed in which the above-mentioned polypropylene film is laminated with a heat-sensitive adhesive resin made of polyethylene or a copolymer containing at least 80% polyethylene and external propylene, butene-1, etc., as well as films that are improved from this. . When using these, prints can be laminated without using solvents or adhesives, so
The above-mentioned problems such as processing time, fire, air pollution, and occupational health can be solved.

However, these films have problems such as adhesion to printed paper, lack of gloss after adhesion, and crushing, depending on the print lamination conditions. Also, special processing equipment or conditions had to be used. Note that "soaked" here refers to the surface condition of the film after adhesion.

[Object and structure of the invention]

Thus, it is an object of the present invention to provide a film for print lamination that solves problems such as disaster prevention during print lamination, as well as problems such as adhesion to printing paper and subsequent gloss. .

Accordingly, the present invention provides a film for print lamination, which is formed by fusion coating a temperature-sensitive adhesive resin made of an acrylic acid-modified ethylene-vinyl acetate resin onto a polypropylene film.

[Detailed description of the invention]

In the present invention, a polypropylene film is used as the base film. This may be biaxial stretching, -axial stretching, or non-axial stretching, and it is desirable that one or both sides of the film be subjected to corona treatment.

This film may be plain or may be printed on one side.

This film is coated with a temperature-sensitive adhesive resin made of acrylic acid-modified ethylene-vinyl acetate resin.

The temperature during painting is 80 to 120°C, and the thickness is in the range of 10 to 20 microns. When one side of the film is printed, the printed side may be coated, or the unprinted side may be coated. An example of the acrylic acid-modified ethylene-vinyl acetate resin used here is Mitsui Polychemical Evaflex #40. It may be used as is or some additives may be added.

An example of a method of print lamination using the film obtained in this way will be explained with reference to a drawing.
1 is a rolled film for print lamination obtained as described above, which is usually 15 microns thick and 780 mm thick.
It is rolled with a width of 3000m. The film 2 is fed by a feed roll 3 and passes through a preheating zone 4 maintained at about 50 to 60° C. at a speed of, for example, 30 m/min. Then, it is sent between a metal heat roll 5 and a heat-resistant rubber pressure roll 6, which rotate in opposite directions while contacting each other. Printed paper 7 to be processed is sequentially fed here from a paper feeder 8, and the film 2 and printed paper 7 are bonded and laminated between both rolls. The print lamination conditions at that time are usually a temperature of 80 to 100°C, a pressure of 200 to 250 kg/cd, and a speed of 20 to 30 m/min, especially a temperature of 90°C, a pressure of 220 cg/cd,
A speed of 30 m/min is preferred. Here, the print-laminated product 9 is further sent by a feed roll 3 and taken out.

In the past, laminating work required paint machines, dryers, etc., as well as measures against hazardous materials and gas poisoning.
According to the present invention, such devices and measures are not required, and the number of processing steps and costs can be reduced.

〔Example〕

A film according to the present invention and other films were made and comparatively tested.

The base films used were polypropylene films with a thickness of 15 microns that had been subjected to two-wheel stretching and corona treatment, and various temperature-sensitive adhesive resins having the following formulations were fusion-coated onto these films to a thickness of 15 microns.

Blend 1: Copolymer resin of 80 ethylene and 200 vinyl acetate Blend 2: Copolymer resin of 60 ethylene and 40 vinyl acetate Blend 3 Niacrylic acid-modified ethylene-vinyl acetate resin Among these, No. 3 is the present invention. This is a film that covers

These films were laminated with printing paper under the following two lamination conditions. The printing paper used in this case is tsubo ff1120.
g/rr? It was an art paper.

Condition 1: 90℃ - 220kg/cd - 30m/min Condition 2: 100℃ - 220kg/cd - 30m/min Measurements were taken when the materials were laminated together.

Gloss and collapse were also measured.

The results are shown in the table below. Regarding gloss and crushing, ◎ indicates very good, ◯ indicates good, and Δ indicates slightly good.

Compound composition and properties From this table it is clear that:

When processed under the laminating condition ■, the composition ■ lacks luster and has poor crushing as a result of insufficient heat. Adhesion on white background is good. Adhesion to the printed surface deteriorates.

Formulation (2) gives a brighter gloss and improves pickling, but as with formulation (2), the adhesion to a white background is strong enough to tear the paper, but the adhesion to the printed surface is weak.

Formula ■ has good crushability, clear luster, and adhesion on white areas.
Strong adhesion across printed areas.

When processed under lamination conditions ■, For combination ■, the crushing was improved and the gloss appeared.

The adhesion on the white background part is good, but the printed part There is insufficient adhesion.

With formulation ■, the crushing improved and the gloss became clearer.

The adhesion of the white background part is good, and the printed part is It got a little better.

Formula ■ has good crushability, clear luster, and adhesion on white areas.
The printed part is firmly adhered to the average.

Therefore, with the combination (■), sufficient adhesive strength can be obtained under the conditions (■■), and it can be applied to the current machines.

Other than this, there was no abnormality in the degree of curl, the surface was smooth, and the solvent resistance was good. Of course, there was no fumarole or flammability.

〔Effect of the invention〕

Thus, when using a print laminating film made by fusion-coating a temperature-sensitive adhesive resin made of acrylic acid-modified ethylene-vinyl acetate resin onto a polypropylene film as in the present invention, it can be used under various laminating conditions compared to conventional films. Compared to other products, we have replaced the product with superior adhesive strength, gloss, and crushability, and of course there are no problems in terms of disaster prevention or environmental hygiene, so it is truly a blind move.

[Brief explanation of drawings]

The drawings are explanatory drawings for explaining a method of print lamination using the film according to the present invention. 2... Film for print lamination, 5... Heat roll, 6... Pressure roll, 7... Printing paper.

Claims (1)

[Claims] A print laminating film made by fusion-coating a temperature-sensitive adhesive resin made of acrylic acid-modified ethylene vinyl acetate resin onto a polypropylene film.