JPS62207646A - Flame-retardant polyester film - 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 (Industrial Field of Application) The present invention relates to a polyester film having excellent flame retardancy.

(Prior art) (Problem to be solved by the invention) Conventionally, as a method for making polyester film flame retardant, (
1) A method of incorporating a flame retardant during polymerization, (2)
) A method in which a flame retardant is added during the melt extrusion process of the film and then melt-extruded, and (3) a method in which the surface of the film is coated with a flame retardant composition are known. However, (1)
In the polyester film obtained in (2), the flame retardant was thermally decomposed during the melt extrusion process, so deterioration of the physical properties of the film was unavoidable.

On the other hand, method (3) is considered to be an excellent method in that it avoids deterioration of physical properties due to thermal decomposition.

As an example of this, JP-A No. 51-24676 describes a thermosetting epoxy resin as the first component, a liquid phosphoric acid compound or a halogen compound as the second component, and a material insoluble in general organic solvents as the third component. JP-A-52-150474 discloses a method of obtaining a flame-retardant polyester film by dispersing a mixed composition containing a powder filler etc. in an organic solvent and applying the mixture to a polyester film. Tetrabromobisphenol A is applied to the surface of a polyester film with a surface average roughness of 0.3 to 0.8 μm.
A thermosetting acrylic resin or other flame retardant is applied as a binder, and then a resin such as vinyl chloride/vinyl acetate copolymer is coated on top of the flame retardant.

A method for obtaining a flame retardant polyester film is disclosed.

However, since all of these methods involve separately coating the flame retardant and thermosetting resin binder on the polyester film, the flame retardant precipitates on the polyester film obtained by these methods, resulting in white powder. There is a problem in that this causes an undesirable appearance. Furthermore, if the amount of flame retardant is reduced in order to avoid such a problem, there is a problem that the flame retardant effect becomes insufficient.

The present inventors have discovered that the problems of conventional flame-retardant polyester films, such as 3 or more, can be solved by laminating a cured phenolaldehyde resin or a cured halogenated phenolaldehyde resin on a polyester film. I applied.

For such flame retardant polyester film.

Not only is there no problem with flame retardant leaching.

It has the advantage that the excellent physical properties of polyester film are maintained.

However, phenolaldehyde resins have poor alkali resistance even if they have been cured, and therefore polyester films laminated with such cured phenolaldehyde resin layers also have poor alkali resistance. There was a problem with sexuality, and it was hoped that it would be improved.

The present invention aims to solve the problem of the alkali resistance of a polyester film laminated with such a cured phenolaldehyde resin.

In other words, 1 object of the present invention is to prevent leaching of the flame retardant and 1
The purpose of the present invention is to provide a flame-retardant polyester film with excellent surface appearance and alkali resistance.

Another object of the present invention is to provide a flame-retardant polyester film that does not suffer from deterioration of physical properties due to thermal decomposition and has excellent alkali resistance.

(Means for Solving the Problems) In order to solve these problems, the inventors of the present invention have made extensive studies and found that the object of the present invention is achieved by laminating cured products made of epoxy resin and halogenated phenol resin. The present invention was achieved by discovering that the following can be achieved.

That is, one aspect of the present invention is a flame-retardant polyester film characterized in that a cured product made of a halogenated phenolaldehyde resin and an epoxy resin is laminated on a polyester film.

Next, nine aspects of the present invention will be described in detail.

The polyester film used in the flame-retardant polyester film of the present invention is a polyester film obtained by a polycondensation reaction of a dicarboxylic acid component and a glycol component, but it may also be a film of a composition of these polyesters. .

Examples of the dicarboxylic acid component constituting the polyester include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalene dicarboxylic acid, as well as aliphatic dicarboxylic acids such as adipic acid and sebacic acid, and mixtures thereof. But that's fine.

Examples of glycol components include aliphatic alkylene glycols such as ethylene glycol and tetramethylene glycol, diglycidyl ether of bisphenol A, glycols of polyalkylene ether, and aromatic diols such as bisphenol and hydroquinone. It may be a mixture of

In addition to dicarboxylic acid components and glycol components, paraoxybenzoic acid, lactones, carbonic acid derivatives, and the like may also be used.

Examples of films of polyester compositions are:

For example, there may be mentioned a film made of a composition in which two or more of polyethylene terephthalate, polybutylene terephthalate, polyarylate polycarbonate, polyester carbonate, etc. are combined.

Furthermore, polyamides such as nylon 6, polystyrene, ABS, and AS may be added to the polyester obtained from the dicarboxylic acid component and glycol component, as long as the properties of the polyester film are not impaired.

Polyolefins such as polyethylene, polypropylene, polymethyl acrylate and polyvinyl alcohol, thermoplastic resins such as polysulfone, polysulfide, polyacecool and polyketone can also be blended.

The polyester used in the polyester film of the present invention contains stabilizers and additives as necessary.

Extending agents, dyes and pigments, crosslinking agents, etc. may be added. In addition, it has a functional group that can be crosslinked, allowing it to withstand light and heat.

Crosslinking can also be carried out by radiation or the like.

As the polyester film in the present invention.

Examples include films obtained by various manufacturing methods such as melt extrusion, calendering, and casting.

Further, as the polyester film in the present invention,
Examples include not only unstretched films but also films stretched in the -axial or biaxial direction.

As the polyester film in the present invention.

It also includes those subjected to surface treatment using physical or chemical means such as corona discharge treatment, matting treatment, steam treatment, and alkali treatment, as required.

Furthermore, on the surface of the polyester film.

A surface modification layer may be provided, or one letter, two figures, a pattern, etc. may be provided.

The thickness of the polyester film in the present invention is as follows:
There is no particular limitation, and it may be of any thickness, from an extremely thin film to a sheet-like thickness.

The cured product made of a halogenated phenolaldehyde resin and an epoxy resin that is laminated on the surface of the polyester film 11 in the present invention is a cured product of a halogenated phenolaldehyde resin and an epoxy resin.

This halogenated phenolaldehyde resin is one in which some or all of the protons of the phenol nucleus are substituted with halogen atoms.

The halogenated phenolaldehyde resin may be produced by any method, and examples include the following.

1) Thermosetting halogenated phenol aldehyde resin obtained from halogenated phenols and aldehydes.

2) Thermosetting halogenated phenol aldehyde resin obtained from halogenated phenols, non-halogenated phenols, and aldehydes.

3) A thermosetting halogenated phenolaldehyde resin obtained by allowing a halogenating agent to act on a liquid or solid thermosetting phenolaldehyde resin obtained from a non-halogenated phenol and an aldehyde. Note that the halogenating agent in this case includes bromine, chlorine, sulfuryl chloride, sulfuryl bromide, etc., and bromine is particularly preferred.

Phenols constituting the halogenated phenolic aldehyde resin in the present invention include phenol and phenol derivatives. Examples of this phenol derivative include m-alkylphenol substituted with an alkyl group having 1 to 9 carbon atoms, 0-alkylphenol,
p-alkylphenol, specifically 2m-cresol, p-ter-butylphenol, 0-propylphenol.

Examples include resorcinol, bisphenol A, and halogenated derivatives thereof.

Examples of the halogenated derivatives include those in which part or all of the protons of the benzene nucleus of the phenols are halogenated, such as monobromophenol, dibromophenol, tribromophenol, and tetrabromobisphenol A.

Note that the phenols are not limited to these, and any other compound containing a phenolic hydroxyl group may be used.

Alternatively, a mixture of two or more of these may be used.

The halogen content of the halogenated phenolaldehyde resin is preferably 1 to 30% by weight, particularly 3 to 15% by weight.

Examples of the aldehydes constituting the halogenated phenolic aldehyde resin in the present invention include compounds having an aldehyde group such as formaldehyde, acetaldehyde, and benzaldehyde, as well as compounds that can be decomposed to generate aldehydes.

The components constituting the halogenated phenolic aldehyde resin in the present invention include not only phenols and aldehydes but also other components.

Examples of such other components include, for example, aqueous alumonia, hexamethylenetetramine, and dimethylamine, which are used as necessary in the production of halogenated phenolaldehyde resins.

Examples include alkylamines such as diethylenetriamine and polyethyleneimine.

As the epoxy resin used in the present invention, any type of epoxy resin available as a general commercial product may be used, but it is preferable to use an Epivis type epoxy resin (for example, Epicoat 82B, 1001, 1 manufactured by Yuka Shell Epoxy Co., Ltd.).
004. Or Ebikuron 840 manufactured by Dainippon Ink Co., Ltd.
．． 1050.7050).

Novolak type epoxy resin (for example, Epicoat 152, 154 manufactured by Yuka Shell Epoxy Co., Ltd.) or.

Examples include Evicron N-730, N-740, N-665, N-670) manufactured by Dainippon Ink.

These epoxy resins have an epoxy equivalent of 150
An epoxy resin having an epoxy equivalent weight of 170 to 250 is preferred, and an epoxy resin having an epoxy equivalent of 170 to 250 is particularly preferred.

The flame-retardant polyester film of the present invention is obtained by laminating a cured product made of a halogenated phenolaldehyde resin and an epoxy resin on the surface of a polyester film. The proportion of epoxy resin in the product is 10% of halogenated phenolaldehyde resin.
10-150 parts by weight, especially 30-120 parts by weight
Parts by weight are preferred; if it is less than 10 parts by weight, the alkali resistance of the flame-retardant polyester film of the present invention will be insufficient, and if it exceeds 150 parts by weight, the flame retardance will decrease.

The flame-retardant polyester film of the present invention is obtained by laminating a cured product made of a halogenated phenolaldehyde resin and an epoxy resin on the surface of a polyester film. The layer of the cured product may be a single layer or a multilayer.

Further, the cured product made of the halogenated phenolaldehyde resin and the epoxy resin may be laminated on either one side or both sides of the polyester film. When laminated on one side, a polymer layer or a metal film may be laminated on the other side.

In the flame retardant polyester film of the present invention.

The thickness of the cured product made of halogenated phenolaldehyde resin and epoxy resin to be laminated on the polyester film layer may be selected from any desired thickness as long as it can impart flame retardancy, but is preferably 0.01 to 50 μm, particularly 0.01 to 50 μm. The thickness is preferably 0.1 to 20 μm. If it is less than 0.01 μm, it will be difficult to form a continuous film, and if it exceeds 50 μm, the flexibility of the flame-retardant polyester film will be impaired or cracks will easily appear on the surface.

There are two different methods that can be used to laminate a cured product made of a halogenated phenolaldehyde resin and an epoxy resin on the surface of a polyester film.
As one of the preferred methods.

Examples include a method in which an uncured halogenated phenolaldehyde resin and an uncured epoxy resin are dissolved in an organic solvent together with a curing agent if necessary, and then applied, and then the organic solvent is removed and a curing treatment is performed.

As the organic solvent, any solvent can be used as long as it can dissolve the uncured halogenated phenol aldehyde resin and the uncured epoxy resin and can be easily removed from the solvent after coating. For example, methyl ethyl ketone,
Examples include acetone and methanol.

The organic solvent solution containing the halogenated phenolic aldehyde resin and the epoxy resin may contain a curing catalyst and
Adhesion promoters, wetting modifiers, plasticizers.

Additives such as stabilizers, antioxidants, lubricants, antifoaming agents, extenders, dyes and pigments can be dissolved and included in the cured product made of the halogenated phenolic aldehyde resin and the epoxy resin.

As a curing catalyst, for example, diethylene triamiso. Triethylenetetramine, diethylaminopropylamine, meta-aminoethylpiperazine.

meta-xylylene diamine, meta-phenylene diamine, 4
．． Amine compounds such as 4'-methylene dianiline,
Acid anhydrides such as phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylnadic anhydride, dodecenyl succinic anhydride, trimellitic anhydride, pyromellitic anhydride, maleic anhydride, or 2-methyl Imidazole, 2-ethyl-4-methylimidazole.

Examples include imidazole compounds such as 2-phenylimidazole, which may be used alone, and
They may be mixed and used as appropriate.

The amount of curing catalyst used is preferably 0.5 to 30 parts by weight, particularly 2 to 10 parts by weight, based on 100 parts by weight of the epoxy resin.

As a method for applying an organic solvent solution consisting of a halogenated phenolaldehyde resin and an epoxy resin to the surface of a polyester film, known coating methods such as a doctor knife, bar coater, gravure roll coater, curtain coater, knife coater, and spinner can be used. In addition to application methods using equipment, spray methods, dipping methods, etc. may be used.

After coating, a halogenation treatment is performed as necessary, and then the solvent is evaporated, and the coating is dried and cured.

The drying and curing treatment not only avoids the blocking phenomenon when the flame-retardant polyester films of the present invention are stacked or rolled, but also improves flame retardancy and alkali resistance.

One of the reasons for the improved alkali resistance is that during the curing process, some of the epoxy groups of the epoxy resin react with the phenolic hydroxyl groups of the halogenated phenolaldehyde resin, reducing the content of phenolic hydroxyl groups in the cured product. This can be mentioned.

The drying and curing conditions are selected within an appropriate range as long as the above effects are obtained. For example, the drying conditions are 4
Preferably, the temperature is 0 to 100°C for 1 to 20 minutes. Further, the curing conditions are 1 second to 20 minutes at a temperature of 100 to 300°C, particularly 150 to 200°C.

Particularly preferred is 5 seconds to 3 minutes.

The flame-retardant polyester film of the present invention can be used in electrical and electronic fields such as membrane stitches, flexible printed circuit (FPC) boards used in automobiles, OA equipment, etc., agricultural greenhouses, etc. This includes the building materials field.

(Example) The present invention will be specifically explained below with reference to two examples. .

Example 1 Add 200 g of phenol to the No. 11 Mitsuro flask.

200 g of 37-t% formalin, 120 g of water, 18 g of hexamethylenetetramine, and 8.4 g of calcium chloride were added with stirring to make a homogeneous solution.
40 g of a 10 wt % aqueous solution of 1-lium fluoride was added, and the temperature was raised to 85° C. for 60 minutes.

The reaction was carried out at the same temperature for 90 minutes to obtain an emulsion of microspherical resol resin.

The flask contents were then allowed to cool to 30°C.

0.5j! After adding 570 g of 3.5 wt % bromine water with stirring, the liquid color changed from reddish brown to colorless, then stirred for 5 minutes, the supernatant liquid was removed, and the microspheroidized resin in the lower layer was removed. The particles were washed with water and air dried.

Next, this was heated under reduced pressure (5 mm/1 g or less) to 50 to 6
It was dried at 0° C. to obtain a brominated phenol formaldehyde resin with an average particle size of about 50 μm.

The bromine content of this resin was 4.5 wt%.

This resin is called resin A.

8 g of this resin A, 3 g of Epicoat 828 (manufactured by Yuka Shell Co., Ltd.), which is an Epibis type epoxy resin, and 0.06 g of 2-methylimidazole were combined with 32 g of methyl ethyl ketone.
1 g, coated on one side of a 75 μm polyethylene terephthalate film, dried at 50°C for 10 minutes, cured at 160°C for 2 minutes,
A polyester film having a thickness of μm and having a Mi layer of a cured product made of a brominated phenolaldehyde resin and an epoxy resin was obtained.

This film is called Film A.

Example 2 8 g of resin A obtained in Example 1, 3 g of novolac type epoxy resin and 0.06 g of phthalic anhydride were dissolved in a mixed solvent consisting of 15 g of methyl ethyl ketone and 15 g of methanol, and the same procedure as in Example 1 was carried out. Coated on one side of 75 μm polyethylene terephthalate and dried.
Perform heat treatment.

A polyester film having a thickness of 10 μm and laminated with a cured product made of a brominated phenolaldehyde resin and an epoxy resin was obtained.

This film is called Film B.

Comparative Example 1 8 g of resin A obtained in Example 1 was mixed with 3 methyl ethyl ketone.
2 g of polyethylene terephthalate, coated on one side of 75 μm polyethylene terephthalate in the same manner as in Example 1, dried, and heat-treated to form a polyester film laminated with a 10 μm thick cured product of brominated phenolaldehyde resin. Obtained.

This film is called Film C.

Films A-C obtained in Examples 1 and 2 and Comparative Example 1 above
For comparison, the 75 μm polyethylene terephthalate film (film D) used in the example was
Flammability was evaluated according to the 94VTM method.

In addition, the surface appearance after being immersed in a 5 wt % aqueous sodium hydroxide solution at 70° C. for 10 minutes and the presence or absence of separation using Sellotape were examined.

Furthermore, the appearance of the film surface was observed after one week at 200°C.

The flame-retardant polyester film of the present invention has excellent flammability and alkali resistance. Furthermore, there is no leakage of flame retardant onto the 2nd surface.

(Effects of the Invention) The flame retardant polyester film of the present invention is imparted with flame retardancy without impairing the properties of the polyester film. Furthermore, since there is no bleed-out of the flame retardant, the two-surface appearance is excellent.

Furthermore, since the laminated cured resin layers have excellent alkali resistance, the flame-retardant polyester film of the present invention also has excellent alkali resistance.

Claims (1)

[Claims] (1) A flame-retardant polyester film characterized in that a cured product made of a halogenated phenolaldehyde resin and an epoxy resin is laminated onto a polyester film.