JPS6134981B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to vapor deposited polyester films.

Films made of polyester films such as polyethylene terephthalate with metals or metal oxides deposited on the surface have high tensile strength, impact strength,
It has high tear strength and extremely low permeability to gases such as oxygen and water vapor, making it suitable for insulation materials, metal threads,
It is widely used as a gas barrier packaging material, and is particularly suitable as a food preservation film. However, conventional metallized polyester films
The adhesive strength between the film and the metal or metal oxide is insufficient, and there are various problems depending on the application. For example, when used as a heat insulating material for building materials, organic solvents such as toluene and methyl ethyl ketone in the adhesive used when installing the heat insulating material reduce the adhesive strength at the interface between the film and the deposited metal, resulting in peeling. This results in a decline in its performance as a building material.
In addition, when used as a packaging material for food preservation, after packaging the food, heat treatment such as high temperature sterilization using boiling water, steam, high temperature heating, dielectric heating, microwave oven, etc. will cause the film and vapor-deposited metal to separate. This caused peeling at the interface, making it impractical for food packaging that requires boil sterilization or retort sterilization.

The present invention provides a vapor-deposited polyester film that solves the above-mentioned conventional problems.
That is, the present invention provides a film made of a modified polyester containing at least a portion of 5-hydroxyisophthalic acid residues, which has a metal or a metal on at least one side of the film.
This is a vapor-deposited polyester film characterized in that a metal oxide or silicon oxide is vapor-deposited.

The modified polyester containing at least a portion of 5-hydroxyisophthalic acid residues in this invention may be a copolymer alone, a polymer mixture of the copolymer and another polyester, or a polymer mixture of 5-hydroxyisophthalic acid and glycol. It may also be a polymer mixture of a polyester obtained from a polyester and another polyester.

The above-mentioned copolymer here is a copolymerized polyester having at least one component of 5-hydroxyisophthalic acid residues, and the other dibasic acid residues include terephthalic acid residues as the main component. Furthermore, as other dibasic acid residues, residues such as isophthalic acid, phthalic acid, sebacic acid, succinic acid, and oxalic acid may be included as constituent components. Some residues of oxyacids such as p-hydroxybenzoic acid can also be used. Examples of glycol residues include residues such as ethylene glycol, propylene glycol, tetramethylene glycol, polyethylene glycol, diethylene glycol, polypropylene glycol, polytetramethylene glycol, neopentyl glycol, and cyclohexanedimethanol. Typically, ethylene glycol or tetramethylene glycol residues are used. When the modified polyester constituting the film is only a copolyester containing at least one component of 5-hydroxyisophthalic acid residue, the copolymerization ratio of the component is usually 0.5.
~50 mol% (relative to total acid residues), preferably 1 to 20 mol%. Copolymerization in a small amount is generally carried out in a batch polymerization kettle, but it is of course possible to carry out the copolymerization continuously.

In addition, the modified polyester constituting the film is a polymer of a copolyester containing at least one component of 5-hydroxyisophthalic acid residues and another polyester (a polyester that does not contain 5-hydroxyisophthalic acid residues as a component). In the case of a mixture, a polyester that does not contain 5-hydroxyisophthalic acid residues as a component is a mixture of dibasic acid (however, 80 mol% or more of this dibasic acid is terephthalic acid) residue and glycol. It is a polyester (hereinafter abbreviated as terephthalic acid polyester) composed of residues. The dibasic acid residues are mainly terephthalic acid residues, but 20 mol% or less may be other dibasic acid residues. Examples of other dibasic acid residues include isophthalic acid, phthalic acid, adipic acid, sebacic acid, succinic acid, and oxalic acid residues.
Some residues of oxyacids such as p-hydroxybenzoic acid can also be used. Moreover, the glycol residue is the same as above. The polymer mixing ratio of copolyester containing at least one component of 5-hydroxyisophthalic acid residue and terephthalic acid-based polyester is such that the ratio of 5-hydroxyisophthalic acid residue to the total acid residues in the polymer mixture is as follows. Usually 0.5~
50 mol%, preferably 1 to 20 mol%
Make it so.

It may also be a polymer mixture of a polyester obtained from 5-hydroxyisophthalic acid and glycol and another polyester. The glycol to be polymerized with 5-hydroxyisophthalic acid can be arbitrarily selected from ethylene glycol, propylene glycol, tetramethylene glycol, neopentyl glycol, etc., and the degree of polymerization thereof may be small. The other polyesters mentioned above can be used as they are.

If necessary, auxiliary agents such as antistatic agents, lubricants, antiblocking agents, antifogging agents, and surfactants may be added to the modified polyester for forming the film.

Aromatic sodium sulfonate-based antistatic agents are effective, and lubricants include silica-based agents such as thyroid, talc, and kaolin, organic and inorganic calcium salts such as calcium terephthalate and calcium carbonate, and lithium acetate. Lithium salts are effective.

The film according to the present invention includes an unstretched film formed into a sheet shape, a stretched film stretched uniaxially or biaxially, and a film formed solely of the modified polyester described above, It includes a laminated film consisting of two or more layers of a polyester film and a normal polyester film. This laminated film consisting of two or more layers is produced by coextrusion, in-line lamination, extrusion lamination, dry lamination, or the like using the modified polyester and ordinary polyester. In the case of the above-mentioned dry lamination method, the normal polyester film is rolled, uniaxially stretched or biaxially stretched, and the modified polyester film may be unstretched, uniaxially stretched or biaxially stretched.

The surface of the film obtained as described above is subjected to corona discharge treatment, flame treatment,
Activation of the film surface can be further improved by optionally performing physical treatment using plasma, etc., chemical treatment using acids, alkalis, oxidizing agents, etc., and anchor coating treatment using adhesives such as isocyanate, ethyleneimine, alkyl titanate, etc. .

The metal or metal oxide deposited on the surface of the film includes metals such as gold, silver, aluminum, zinc, and tin, and their oxides, and also includes silicon oxide. Vapor deposition on the film surface can be performed by a conventional method.

The vapor-deposited polyester film of the present invention has excellent organic solvent resistance, water resistance, hot water resistance, and heat resistance. It never decreases. Further, the film of the present invention has antistatic properties.

Polyethylene, polypropylene, ionomer, ethylene,
Sheets or films of vinyl acetate copolymer, ethylene/ethyl acrylate copolymer, polyester, polyamide, etc. can be laminated and used.

Examples of the present invention will be described below.

Example 1 5-hydroxyisophthalic acid residues are composed of 5 mol% of 5-hydroxyisophthalic acid, 95 mol% of terephthalic acid as dicarboxylic acid residues, and 100 mol% of ethylene glycol as glycol residues. Copolymerized polyester containing mol% was melt extruded at a temperature of 295℃ to determine the thickness.
A 120μ unstretched film was obtained. Next, the film was stretched 3.5 times in the machine direction at 85°C, then stretched 3.2 times in the cross direction at 135°C, and further heat-set at 200°C for 10 seconds. The resulting film had a thickness of 12.2μ. One side of this polyester film was subjected to a corona discharge treatment, and then aluminum was vapor-deposited by a conventional method. This aluminum vapor-deposited film was immersed in boiling water for 3 minutes, then taken out and placed on the vapor-deposited surface.
When a test was repeated 10 times in which a 23 mm wide cellophane tape was crimped, one end of the cellophane tape was bent in a 180 degree direction, and the cellophane tape was rapidly peeled off. was 0 to 5% of the total area, and the vapor-deposited surface was hardly peeled off.

For comparison, the above peeling test was performed on an aluminum-deposited polyester film obtained in the same manner as in the above example using ordinary polyethylene terephthalate consisting of a terephthalic acid component and an ethylene glycol component without blending 5-hydroxyisophthalic acid. As a result, the area of the vapor-deposited metal that adhered to the cellophane tape and was peeled off was 70 to 100% of the total area, and was peeled off over almost the entire surface.

Example 2 Copolymerized polyester 50 composed of an acid component with 10 mol% of 5-hydroxyisophthalic acid residues and 90 mol% of terephthalic acid residues and an ethylene glycol component
and 50 parts of polyethylene terephthalate were melt-extruded in the same manner as in Example 1 above,
A biaxially stretched film was obtained by stretching and heat setting, and a peeling test of a film on which aluminum was deposited on the biaxially stretched film in the same manner as in Example 1 showed that the peeling rate was 0 to 5% of the total area, and the deposited surface was Almost no peeling occurred.

Claims (1)

[Claims] 1. A vapor-deposited polyester film, characterized in that a metal, metal oxide, or silicon oxide is vapor-deposited on at least one side of a film made of a modified polyester containing at least a portion of 5-hydroxyisophthalic acid residues.