JPS6063158A - 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 laminate mainly composed of biaxially oriented polyparaphenylene sulfide film.

[Prior art]

As electrical equipment, automobile parts, etc. become smaller and lighter and have higher performance, there is a strong demand for improvements in system reliability (especially thermal properties under high humidity), electrical properties, mechanical properties, flame retardance, etc. Furthermore, it has become necessary to have a well-balanced combination of these properties. Conventionally, the most commonly used material in this field is a laminate of polyester film and aromatic polyamide paper.

However, such conventional laminates have a serious drawback in that electrical insulation and mechanical strength rapidly decrease when used in a high temperature and high humidity atmosphere.

Furthermore, even in a dry atmosphere, conventional laminates
It is no longer possible to meet the demands for heat resistance of materials in recent high-performance equipment.

[Purpose of the invention]

An object of the present invention is to provide an electrically insulating laminate that can withstand long-term use in a high-temperature, high-humidity atmosphere and is far superior to conventional materials in terms of general properties as an electrically insulating material. It is something.

[Structure of the invention]

The present invention relates to a laminate comprising a biaxially oriented film in which 70 or more molar units of repeating units have the structural formula: and a fiber sheet of an aromatic polymer having no melting point.

Polyparaphenylene sulfide (hereinafter p) in the present invention
(referred to as ps) means metaphenylene for repeating units whose repeating units have a molar coefficient of 7D or more (preferably 90 molar or more) and a structural formula of
(selected from alkyl groups, alkoxy groups, nitro groups, phenyl groups, sulfonic acid groups), trifunctional phenyl sulfides, and these may be contained in either block copolymerization or random copolymerization. good. Further, the fact that the structural units are connected at or near the end of the polymer does not change the essence of the present invention.

Furthermore, other components such as polymers, additives, and inorganic fillers mixed for other purposes may be contained in the composition in an amount of 101% by weight or less, preferably 5% by weight or less.

A biaxially oriented PPB film is a film whose tensile strength at break is 15 kg 7 mm" or more obtained by melt-molding the above PPS, forming it into a sheet, biaxially stretching it, and heat-treating it. Its thickness is 2 A range of ~500 μm is preferred, but
The thickness is preferably in the range of 5 to 200 μm. Also, the p
ps Biaxially oriented films whose surfaces are subjected to surface modification treatments such as corona discharge treatment, plasma treatment, chemical treatment, or primer coating for the purpose of improving adhesion are also included in the present invention. Needless to say.

In the present invention, the aromatic polymer having no melting point means that the decomposition point of the main component constituting the polymer is lower than its theoretical melting point. It is a polymer that cannot be made into fibers by so-called melt spinning.

1. Aromatic polyamide [1] Polymer obtained by condensation of aromatic dicarboxylic acid and aromatic diamine For example, polymetaphenylene isophthalamide obtained by condensing isophthalic acid chloride and metaphenylene diamine in a polar solvent. (2) Polymer obtained by condensing aromatic aminocarboxylic acids (3) Copolymer 2 of (1) above, +21, aromatic polyamideimide 6, aromatic polyimide 4, aromatic polyesterimide 5, aromatic Polyamide imidazole 6 Examples include aromatic polyamide and hydrazide, but aromatic polyamide is most preferred.

The fiber sheet in the present invention is a thin sheet made of an aggregate of fibers of the above polymer.

It is a general term for 9 things that are usually called paper, non-woven fabric, woven fabric, felt, etc.

The thickness of the fiber sheet is preferably in the range of 10 to 1000 μm (preferably 20 to 200 μm), the thickness of the constituent fibers is 100 μm or less, and the basis weight is 2 to 600 μm.
g/m" (more preferably 5 to 150 g/m").

Further, there is no problem in the case that a small amount of 1' other than fibers, such as an adhesive, is included in the fiber sheet for the purpose of binding the fibers together.

The laminate in the present invention is composed of one or more layers of biaxially oriented PP5 film and one or more layers of fiber sheets of an aromatic polymer with no melting point, and its overall composition can vary depending on the purpose of use. It can be a laminate of layers, three layers or more. In many uses pps
A three-layer structure consisting of a biaxially oriented film and the above-mentioned fibers laminated on both sides is preferred, but for applications requiring a high dielectric breakdown voltage per unit thickness, the above-mentioned fiber sheet may be used. A three-layer structure in which pps biaxially oriented films are laminated on both sides is preferred. Moreover, the laminate is Pps
A biaxially oriented film and an aromatic polymer fiber sheet are laminated directly or via an adhesive or the like.

The thickness of the laminate is preferably in the range of 12 to 1500 μTn (more preferably 60 to 500 μm).

Moreover, as the most preferable example of the laminate, the thickness is 20 to 2
50 μm PPS biaxially oriented film and thickness 20-15
01im's aromatic polyamide vapor is polyamide-based, epoxy-based, polyester-based, polyester-imide-based, and polyamide-imide-based.

Examples include those laminated using a silicone-based adhesive or the like.

Next, a method for manufacturing the laminate of the present invention will be described.

First, pps used in the present invention is basically a mixture of a dihalogenated aromatic compound represented by p-dichlorobenzene and substantially the same molar amount of sodium sulfide or sodium hydrosulfide and caustic soda using N-methylpyrrolidone as a solvent. It is obtained by high-temperature reaction of sulfur-containing compounds represented by. Before starting the polymerization reaction, first add sodium sulfide (or a compound capable of synthesizing sodium sulfide) to N-methylpyrrolidone, and then add a polymerization auxiliary agent in an amount of 10 to 100 moles per sodium sulfide. Then, as a polymerization aid, an alkali metal carboxylate such as lithium benzoate is used.Next, as a monomer, a dihalogenated aromatic compound (of which 98 to 105 mol. Add p-dichlorobenzene (more than 70 mol of p-dichlorobenzene), seal the reaction system after sealing with nitrogen, and polymerize at 230 to 280°C for about 2 to 6 hours.After the reaction is complete, the cooled system has a sufficient amount. The polymer is obtained in powder or granule form, washed several times with water and then dried to provide the polymer used in the present invention.

This polymer can be formed into a biaxially oriented film by well known methods. That is, the resin melted by the extruder is
Quantitatively cast from the nozzle onto the cooling drum,
By rapid cooling, a non-oriented, amorphous sheet is formed. Next, this sheet is sequentially biaxially or simultaneously biaxially stretched, but generally, sequential biaxial stretching is performed in the longitudinal direction (longitudinal stretching) between rolls having different circumferential speeds, and then transverse stretching is performed in a tenter. . Next, the obtained biaxially stretched oriented film is heat-treated for a fixed length in the same tenter, and then relaxed as required. Relaxation is carried out in the lateral direction by reducing the distance between the rails at the rear of the tenter by a certain ratio, and in the longitudinal direction by reducing the peripheral speed of the roll by a certain ratio using a suitable device after leaving the tenter. In each case this ratio is within a few percent.

In order to produce the PPS biaxially oriented film used in the present invention in the process of manufacturing such a biaxially oriented film, longitudinal and lateral stretching conditions and heat treatment conditions are particularly important. That is, in the longitudinal stretching step, the stretching is carried out at a sufficiently large magnification within the range that allows transverse stretching, preferably so that the degree of optical orientation after stretching and immediately before transverse stretching is in the range of 0.10 to 0.20. Actual stretching temperature.

The stretching ratio varies depending on the polymer, but it is generally 90 to 1.
It is preferably within the range of 3.0 to 6.0 times at 10°C.

Next, in the transverse stretching step, it is desirable that the degree of optical orientation after stretching is within the range of 0.05 or more -1· in both the longitudinal and lateral directions. Actually, the temperature ratio for horizontal stretching is determined depending on the orientation strength of the longitudinally stretched film, but it is preferably 95 to 120°C.
in.

It is within the range of 2.0 to 5.0 times. The subsequent heat treatment is performed within the range of 200°C to 270°C.

The obtained film has excellent heat resistance and moist heat resistance.

It has electrical properties, flame retardancy, and chemical resistance.

Next, a method for manufacturing the fiber sheet used in the present invention will be described. First, the above-mentioned aromatic polymer is spun by a method such as a dry spinning method or a wet spinning method, and if necessary, stretching, heat treatment, etc. are performed to obtain fibers of the polymer.

A dry method or a wet method can be used to obtain a fiber sheet from the fibers thus obtained.

As a dry method, 9 is a method using a normal densification machine.

Examples include a needle punch method, a spunbond method, a method of opening a long fiber sheet, and a method of making a fiber sheet by applying an adhesive to short fibers. In the wet method, fibers or fibrids dispersed in water are bonded using heat or an adhesive using an ordinary paper machine or the like to form a fiber sheet. Further, depending on the purpose of use, the fibrous sheet may be calendered to change the porosity.

The most preferable aromatic polyamide-based heper for the fiber sheet is obtained by polymerizing metaphenylenecyaminte isophthalic acid chloride in a polar solvent and forming polymetaphenylene inphthalamide into short fibers by a dry spinning method.
Wet-formed paper and pear 1 are then obtained by thermal calendering, if necessary, for the purpose of improving mechanical properties and electrical insulation properties.

The PP5 biaxially oriented sheet and the fiber sheet thus produced are made into a laminate by direct thermocompression bonding or by using an adhesive. The adhesives used here are thermoplastic resins and thermosetting resins.

selected from polyamide, polyimide, polyamideimide, polyurethane, etc., and mixtures or alloys thereof.

Silicone-based, polyester-based, polyesterimide-based, epoxy-based and mixed adhesives thereof can provide preferred laminates. In practice, an adhesive is applied to one of the materials, and if necessary, a drying process is performed, and then the other material is stacked and hot pressed to form a laminate. For laminations of three or more layers, apply adhesive to one material or a laminate of two or more layers, dry if necessary, then stack the other materials (including laminates of two or more layers) and heat. created by pressing. The hot pressing method can be applied to a flat plate or between rolls. Further, it is preferable that the surface of the pps film or fiber sheet used in the present invention is subjected to surface modification treatment such as corona discharge treatment, plasma treatment, chemical treatment, or primer coating prior to lamination.

〔Effect of the invention〕

Since the laminate of the present invention is a laminate of a pps biaxially oriented film and a fiber sheet of an aromatic polymer having no melting point,
The result is an excellent electrically insulating thin film that can stably maintain its initial properties for a long period of time even under high temperature and high humidity conditions, where conventional laminates could not be used. In addition, regarding the combination of constituent materials, the conventional laminate consisting of a polyester film and a fiber sheet of polymetaphenylene isophthalamide improves the heat resistance of the polyester film alone by only about 10 times, whereas the present invention's PP52-axis orientation improves the heat resistance by only about 10 times. A laminate consisting of a film and the above-mentioned fiber sheet can improve the heat resistance of the PPS film alone by a factor of 20 or more.

A laminate with significantly improved moisture and heat resistance and heat resistance is useful for expanding the usage environment of electrical parts, automobile parts, etc., and promoting miniaturization and weight reduction.

[Method of measuring characteristics, evaluation criteria]

Note that the method for measuring characteristics and evaluation criteria in the present invention are as follows.

(1) Set the sample film in a polarizing microscope equipped with an optical orientation angle so that the film surface is perpendicular to the optical axis.

Furthermore, the sample is inserted so that it has an azimuth angle of 45° with respect to the analyzer axis. Next, the sample is rotated around the optical axis and placed at a phase reduction position (a position where the phase difference generated by the sample is reduced by the convencator) located in the direction of plus or minus 45 degrees from the extinction position. When the birefringence of the sample changes, the optical path difference Fo is calculated from the compensation value of the compensator.

Fo/d. The optical distribution nr nβ is defined as follows.

(Here d. represents the thickness of the sample). Note that the direction perpendicular to the rotation axis of the compensator on the sample is the γ direction of the sample, and the parallel direction is the β direction.

In the present invention.

Nippon Kogaku polarizing microscope POH type.

Leitz universal stage.

The measurement was carried out using a monochromatic light of sodium D line (wavelength: 0.589'3 μm) using a Leitz convencator.

(2) Dielectric breakdown voltage According to ASTM D-149.

(3) Tensile multi-property A S T M-D-882-64T in the longitudinal direction (
M D ) is defined as n+.

(4) Heat and humidity resistance Retention rate of dielectric breakdown voltage after 1000 hours of exposure to saturated steam at 200°C.

(5) Tensile elongation rate after exposure to a heat resistant 200'a oven until the tensile elongation becomes 1/2 of the initial value.

(6) Burning speed According to AS'I'M-D-635.

〔Example〕

Hereinafter, the present invention will be described in detail based on Examples.

Example 1 (1) Replenishment of biaxially stretched polyparaphenylene sulfide film 100! In an autoclave with a capacity of 100 mol of sodium sulfide nonahydrate, 45 mol of anhydrous sodium benzoate, 2
51 N-methylpyrrolidone was added and heated while stirring, and the water contained therein was removed by distillation. Water heated to an internal temperature of 220°C and containing a small amount of N-methylpyrrolidone 15.14
was removed. 99 mol of p-dichlorobenzene and 56 g of 1.2.4) dichlorobenzene were added to the dehydrated system together with 5 kg of N-methylpyrrolidone.
After pressurizing to 3 kg/- under nitrogen at 260 DEG C., the temperature was raised and polymerization was carried out at 260 DEG C. with stirring for 2 hours. After the polymerization was completed, the mixture was cooled, the hepolymer was precipitated in distilled water, and the pH was adjusted to 6.5 with hydrochloric acid. After that, the polymer was collected in small lumps using a wire mesh having 150 mesh openings.

After washing this polymer with distilled water under heating, it was dried at 120°C under reduced pressure, and the melt viscosity was 6 at 300°C.
A white polymer with 500 voids (shear rate 200 seconds) was obtained. This polymer was extruded into pellets at 620°C using a 30mmφ extruder, and then 180°
It was dried under reduced pressure at C for 2 hours.

A cap with a width of 220 mm and a 6μ
It is extruded from a 40 mm diameter extruder at 520°C through a sintered metal filter having a mesh size of about 1.5 mm, onto a metal drum with a surface temperature of 50°C. A nearly amorphous transparent film with a thickness of [10[]μ was obtained. This film was stretched 6 to 7 times in the longitudinal direction by a stretching method using a three-roll multi-idler roll whose surface temperature was maintained at 95°C.
Subsequently, the film was stretched 3.8 times in the width direction by a tenter method using clips.

Heat set at 240℃ for 60 seconds to create a biaxial i with a thickness of about 75μ.
A stretched polyethylene sulfide film was obtained. The tensile strength of the film at break is 23 kg/an'' in the longitudinal direction.
It was 21 kg/mm' in the width direction.

The film was also subjected to a corona discharge treatment prior to application of the adhesive.

(2) Preparation of aromatic polyamide fiber sheet Polymetaphenylene isophthalamide obtained by solution polymerization in a polar solvent using metaphenylene diamine and isophthalic acid chloride as raw materials is dry-spun into short fibers. Subsequently, the short fibers were dispersed in water and then made into paper to obtain a fiber sheet.

The fiber sheet has a basis weight of 20 g/m” (thickness of 50
μm).

(3) Preparation of adhesive The adhesives used here were: dimer acid polyamide (Henkel product) Salon 1165) 60% by weight, bisphenol A epoxy resin (Shell company Epicoat≠864) 60% by weight, Timer acid glycidyl ester modified product (Shell company product Epicoat +872) 8% by weight
This is a phenol prepared by mixing and dissolving 2 parts by weight of imidazole in dimethylformamide to give a concentration of 40% by weight and a viscosity of 2 poise.

(4) Creation of laminate The adhesive shown in (3) was applied to the pps film shown in (11) above, and dried at 110°C for 2 minutes and at 140°C for 1 minute.The thickness of the adhesive layer was This adhesive-coated film and the aromatic polyamide fiber sheet shown in (2) were then stacked so as to have a bonding strength of 20 μm and were continuously rolled using a roll simulator. A two-layer laminate film was obtained by thermocompression bonding.The roll temperature at this time was 120°C, the pressure was 3 kg/mm, and the time was 1 second.Furthermore, the Pr8 side of this two-layer laminate film was An adhesive was applied by the method described above, and the aromatic fiber sheets were thermocompression bonded to obtain a three-layer laminate (A of laminate 1).

For comparison, the ppS film constituting the laminate was replaced with a biaxially oriented film of polyethylene terephthalate (hereinafter referred to as PET) having an intrinsic viscosity of 0.61 (the above (1)).
The film was manufactured in the same state as the U.S.A., and the tensile strength at breakage was 24 kg/mm' in the longitudinal direction and 25 kg/mm' in the width direction.
A laminate was produced in the same manner as described above (referred to as B of laminate 1).

(51 Evaluation Table 1 shows the evaluation results of the obtained laminates and the films or fiber sheets that constitute these laminates.

It can be seen from Table 1 that the laminate of the present invention has significantly superior moisture and heat resistance compared to conventional laminates. In addition, in terms of normal heat resistance, the conventional &'f laminate has only a slight change in direction compared to the PET biaxially oriented film alone, which is its constituent material, whereas the laminate of the present invention has The heat resistance significantly exceeds that of the PP5 biaxially oriented film alone, which is the raw material, which shows the uniqueness of the combination of materials used in the present invention.

Note that the polyphenylene isophthalamide fiber sheet alone, which is the other material used in this example, has an extremely low dielectric breakdown voltage of approximately 1 kV, and therefore is not used alone, so no evaluation was performed.

Table 1 Example 2 A laminate in which the structure of Example 1 was replaced with two layers, that is, PPS
A two-layer laminate of a biaxially oriented film and an aromatic polyamide fiber sheet was prepared in the same manner as in Example 1 (laminate 20
A).

For comparison, the above PP52-axis film was used in Example 1.
A laminate was produced in the same manner except for the PET biaxially oriented film used for comparison (referred to as laminate 2 B).

Table 2 shows the evaluation results of the obtained laminates.

From Table 2, it can be seen that the two-layer structure has the same effect as the six-layer structure of Example 1.

Table 2 Example 6 A laminate having the same structure as in Example 1 except that the PPS film and the polymetaphenylene inphthalamide fiber sheet were replaced. That is, a three-layer laminate (A of laminate 3) consisting of a polymetaphenylene isophthalamide fiber sheet on both sides and a PPS film on both sides, and a laminate for comparison (laminate 3) consisting of a PNAT biaxially oriented film on both sides. 30B) was created.

Table 6 shows the evaluation results of the obtained laminates.

From Table 3, it can be seen that the above configuration also has the same effects as the configurations of Examples 1 and 2.

Table 6 Procedures Amendment Self-vomiting duck 12. 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000, Commissioner, Kazuo Wakasugi, Indication of the case, 1982 Patent Application No. 171096, 2, Name of the invention laminate 3, Person making the amendment, Relationship to the case Patent applicant address Nihonbashi Muromachi, Chuo-ku, Tokyo 2-2-4, date of amendment order spontaneous 5, number of inventions not increased by amendment 6, "Detailed description of the invention" column 7 of the specification subject to amendment, content of amendment (1) Description No. 2 On the 7th line of the page, "recently high" is corrected to "recently".

(2) Same page 4, line 2 ``No machining 111J is corrected to ``machining, inorganic''.

(3) Same page 4 line 18 Correct "to form" to "to form."

(4) On page 5, line 14, "polyamide and hydrazide" is corrected to "polyamide hydracite."

(5) Same, page 13, line 1 Correct "thin thallus" to "thin thallus".

(6) Same page 15, lines 7-8 Correct the "retention rate of tensile extension of time" to "time".

(7) Same page 15, line 12 Correct "doesn't explain clearly" with "doesn't explain".

(8) Same, page 15, line 16 Correct “Film Supplement” to “Film Preparation J”.

Claims (1)

[Claims] A laminate consisting of a biaxially oriented film and a fiber sheet of an aromatic polymer with no melting point.