JPH0516346B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a laminated film using a biaxially oriented poly-p-phenylene sulfide film. [Prior art] Conventional films include (1) biaxially oriented poly-p-
The use of phenylene sulfide film as an electrical insulating material is known from, for example, Japanese Patent Laid-Open No. 55-35459. Also (2) polyester film, (3)
It is also known to use polyimide films and the like for similar purposes. Also known are printed wiring boards in which electrical circuits made of conductive paint, resistive paint, metal foil, etc. are formed on these films. In addition, as a laminated film, (4) biaxially oriented poly-p-phenylene sulfide film is used as the center layer, and polyethylene terephthalate, polyethylene terephthalate,
Magnetic recording media are made by laminating biaxially oriented polyester films made of polyethylene 2.6 naphthalate, etc., fully aromatic polyamide films, fully aromatic polyimide films, etc., each with a thickness within 50% of the thickness of the center layer. It has been proposed in Japanese Patent Application Laid-Open No. 60-80125 to use it as a base film. [Problems to be Solved by the Invention] However, the above-mentioned conventional film has the following problems. Biaxially oriented poly-p-phenylene sulfide film lacks impact resistance, and when used as a slot liner or wedge for a motor, for example, two or more layers may peel off (delamination) inside the film. It is easy to get wet and tear. Polyester film has poor heat resistance. Although polyimide film has high heat resistance, it has a high water absorption rate and requires moisture management during use, or it is difficult to manufacture thick films exceeding 125 μm, making it difficult to automatically insert slot liners or wedges. There are some drawbacks. The film has a biaxially oriented poly-p-phenylene sulfide film as the center layer and polyester films are laminated on both sides.By using the biaxially oriented polyester film as the surface layer, the impact resistance can be improved to some extent. I can see it, but it's not enough. The object of the present invention is to solve these problems and provide a film that has excellent heat resistance and impact resistance. [Means for Solving the Problems] The present invention is a laminated film in which biaxially oriented poly-p-phenylene sulfide films are laminated on both sides of a biaxially oriented polyester film via an adhesive. , the hardness index of the adhesive layer is 1 to 3000
The thickness of one biaxially oriented poly-p-phenylene sulfide film is A, and the thickness of the other biaxially oriented poly-p-phenylene sulfide film is in the range of
A′ and thickness B of biaxially oriented polyester film
The invention relates to a laminated film characterized in that it satisfies 0.2≦(A+A′)/B≦3.6. In the present invention, biaxially oriented poly-p-phenylene sulfide film (hereinafter sometimes abbreviated as PPS-BO) refers to a resin composition containing poly-p-phenylene sulfide as a main component. This is a film obtained by melt-molding, forming into a sheet, biaxially stretching, and heat-treating. The degree of orientation of the film was determined by wide-angle X-ray diffraction as 2θ=20.
The degree of orientation OF obtained for the crystal peak at ~21 degrees is
It is preferably in the range of 0.07 to 0.50 in the End direction and Edge direction, and in the range of 0.60 to 1.00 in the Through direction. Further, the thickness of the film is preferably in the range of 3 to 200 microns. In the present invention, a resin composition containing poly-p-phenylene sulfide as a main component (hereinafter sometimes abbreviated as PPS-based composition) refers to a resin composition containing 90% by weight of poly-p-phenylene sulfide. Refers to a composition containing the above. If the content of PPS is less than 90% by weight, the crystallinity, thermal transition degree, etc. of the composition will be low, and the characteristics of the film made of the composition, such as heat resistance, dimensional stability, and mechanical properties, will be impaired. The remaining less than 10% by weight of the composition may contain additives such as polymers other than PPS, inorganic or organic fillers, lubricants, colorants, ultraviolet absorbers, etc., as long as they do not harm the purpose of the present invention. do not have. The melt viscosity of the resin composition is preferably in the range of 500 to 12,000 poise (more preferably 700 to 10,000 poise) at a temperature of 300 DEG C. and a shear rate of 200 l/sec from the viewpoint of film moldability. The melt viscosity of the resin composition is equal to the melt viscosity of the finally obtained biaxially oriented poly-p-phenylene sulfide film. In the present invention, poly-p-phenylene sulfide (hereinafter sometimes abbreviated as PPS) refers to 70 mol% or more (preferably 85 mol%) of repeating units.
above) is the structural formula

[Application]

The laminated film of the present invention is suitable for use as a general electrical insulating material, as well as printed wiring boards, sheet keyboard boards, acoustic diaphragms, and the like. It is especially suitable for applications that require a high-level balance between heat resistance and impact resistance, such as motor slot liners and wedges. Next, methods for measuring characteristics and evaluation criteria used in describing the present invention will be described. (1) Hardness index Hardness is the peel length (mm/min) per minute when a 10 mm wide laminated film is maintained at 180°C and a peel load of 80 g/cm is applied to the film layers on both sides of the adhesive layer. It was used as an index. A hot air oven was used to maintain the laminated film at 180°C. (2) Impact resistance Measured using a Scotto type fir tester (manufactured by Toyo Baldwin). It is expressed as the number of times the film is rubbed until delamination occurs when the sample is attached to the device and pressed and subjected to reciprocating motion. In addition, the sample was measured in the longitudinal direction of the laminated film, and the pressure bonding load was 0.5 kg. (3) Heat resistance A sample was exposed in an oven at 180°C, and the sample was taken out every 240 hours to measure the tensile elongation rate, which was expressed as the time it took to reach 1/2 of the initial value. In addition,
The tensile elongation rate was measured according to ASTM D882-61T. (4) Orientation degree of PPS-BO Align the stretching direction of each sample, thickness 1 mm, width 1
mm and length 10 mm (each film was fixed using a 5% amyl acetate solution of collodion during molding), and X-rays were incident along the film surface of the film (Edge and End directions). I took a photo of the plate. The X-ray generator used was a D-3F model made by Rigaku Denki, and the power was 40KV-20mA, passed through a Ni filter.
Cu-K rays were used as the X-ray source. The distance between the sample and the film was 41 mm, and a multiple exposure (15 and 30 minutes) method was used using Kodatsu non-screen type film. Next, the intensity of the (200) peak on the plate photo is φ = 0° (on the equator line) 10°,
Scan the densitometer in the radial direction from the center of the photograph at 20° and 30° positions, read the degree of blackening I, and calculate the degree of orientation (OF) of each sample as OF=I(φ=30°)/I(φ=0° ) was defined. Here, I (φ = 30°) is the maximum intensity of 30° scanning,
I (φ=0°) is the maximum intensity of the equatorial scan. In addition,
I(φ=0°) is φ=0° and φ=180°, I(φ=30°)
The average value of the intensity at φ=30° and φ=150° was used. The measurement conditions of the densitometer are as follows. The device used was Sakura Microdensitometer Model PDM-5 Type A manufactured by Roku Konishi Photo Industry.
Measurement concentration range is 0.0 to 4.0D (minimum measurement area 4μ ² conversion), optical system magnification 100x, slit width 1μ, height 10μ
using a film moving speed of 50 μ/sec and a chart speed of 1 mm/sec. [Example] Next, the present invention will be explained in detail by giving examples. Example 1 (1) PPS-BO adjustment used in the present invention. (a) Preparation of PPS polymer 32.6Kg (250kg) of sodium sulfide in an autoclave
mol, including 40% by weight of water of crystallization), 100 g of sodium hydroxide, 36.1 kg (250 mol) of sodium benzoate,
and N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) 79.2 kg were gradually added while stirring.
The temperature was raised to 205°C, and 7.0 kg of distillate containing 6.9 kg of water was removed. 1,4-dichlorobenzene in the residual mixture
Add 37.5Kg (255mol) and NMP20.0Kg, 265
Heated at ℃ for 4 hours. The reaction product was washed 8 times with boiling water, μ, 2900 poise, N, 1.17, Tg 91℃,
High polymerization degree PPS with Tm285℃21.1Kg (yield 78
%) was obtained. (b) Melt molding After drying the composition obtained in (a) above at 180°C for 2 hours under reduced pressure, 0.1% by weight of calcium stearate powder was added as a lubricant to the composition, and the mixture was stirred with a mixer. After mixing, put it into the hopper of a 40mmφ extruder. The composition melted at 310° C. was extruded from a die having a linear lip with a length of 250 mm and a gap of 1.5 mm, and was cast onto a metal drum whose surface temperature was maintained at 30° C. and solidified by cooling. The obtained film has a width of 230 mm, a thickness of 450 μm,
It was an unstretched film with a density of 1.315. (C) Biaxial stretching and heat treatment The film obtained in (b) above was stretched 3.9 times in the longitudinal direction of the film at a stretching temperature of 98°C using a longitudinal stretching device consisting of a group of rolls, and then the film was placed in a tenter. Supplied and stretched 3.7 times in the width direction at a stretching temperature of 98℃,
In addition, the temperature was increased to 270℃ in the subsequent heat treatment chamber in the same tenter.
A biaxially oriented film was obtained by heat treatment for 10 seconds. Further, the film was forcibly shrunk at 250°C for 2 minutes in a free state. Furthermore, on one side of the film
A corona discharge treatment of 6000 J/m ² was performed, and this film was designated as PPS-BO-1 (thickness: 30 μm). (2) Preparation of biaxially oriented polyester film used in the present invention Polyethylene terephthalate (hereinafter sometimes abbreviated as PET) with an intrinsic viscosity of 0.62, which is polymerized from dimethyl terephthalate and ethylene glycol.
After drying the resin raw material chips under reduced pressure, 0.1% of silica powder ("Syroid-150" (manufactured by Fuji Davison)) was
After adding % by weight and stirring and mixing with a mixer, 40
Pour into the hopper of the mmφ extruder. 290
The composition melted at ℃ was 250 mm in length and 1.0 mm in gap.
The film was extruded through a die having a linear lip, cast onto a metal drum whose surface temperature was maintained at 50°C, and cooled and solidified to obtain an unstretched film. The film was stretched 3.3 times in the longitudinal direction at a temperature of 90°C using a longitudinal stretching device consisting of a group of rolls, then the film was fed to a tenter, stretched 3.5 times in the width direction at a stretching temperature of 95°C, and further stretched in the same direction. In the heat treatment chamber following the tenter
A biaxially oriented film was obtained by heat treatment at 240°C for 10 seconds. Furthermore, the film was allowed to freely shrink at 200°C for 2 minutes. Further, one side of the film was subjected to corona discharge treatment at 6000 J/m ² to obtain a biaxially oriented polyester film with a thickness of 50 μm. (This film is PET
-BO-1). (3) Adjustment of adhesive The following commercially available heat-resistant polyurethane adhesive was used. “Adcoat” 76P1 manufactured by Toyo Morton Co., Ltd. (this adhesive is referred to as adhesive-1). The mixing ratio of the main agent and curing agent of the above adhesive is
The hardening agent was adjusted to 100/8 and the solid content concentration was adjusted to 32% by weight using ethyl acetate as a solvent. (4) Laminated film preparation The corona-treated surface of PPS-BO-1 was coated with the adhesive prepared previously using a gravure roll method.
The drying conditions for the solvent were 80° C. for 3 minutes, and the thickness of the adhesive was adjusted to 7 μm after curing. Subsequently, it was laminated with PET-BO-1 using a subsequent roll laminator. The bonding conditions were a temperature of 80℃ and a linear pressure of 3Kg/
cm. Next, the corona-treated surface of another layer of PPS-BO-1 is coated under the above conditions, and the PET-BO-1 side of the previously obtained two-layer body of PPS-BO-1/PET-BO-1 is coated. was bonded under the above conditions. The obtained laminated film was cured at 60°C for 50 hours, and further at 150°C for 10 hours. (Laminated film-1) The hardness index of the adhesive of the obtained laminated film is:
The number of layers stacked first was 547, and the number of layers stacked later was 519. (5) Evaluation The impact resistance and heat resistance of the laminated film produced above were measured. Also, for comparison, 125μm PPS−
BO made a similar evaluation. The results are shown in Table 1. From this result, the laminated film is PPS-BO
It is clearly seen that the impact resistance has been significantly improved without significantly reducing the excellent heat resistance of the material.

[Table] Example 2 (1) Creation of laminated film PPS with different thicknesses in the same manner as Example-1
Created a BO. The thickness of the film is 8μm,
There are six types: 12μm, 15μm, 30μm, 38μm, and 50μm. On the other hand, PET-BO is also 25μm,
Six different thicknesses were created: 38 μm, 50 μm, 75 μm, 100 μm, and 125 μm. Using the above films, nine types of laminated films of A/B/A' were prepared with different thickness configurations.
The lamination conditions were the same as in Example 1, and the thickness of each adhesive layer was 4% of the total thickness of the laminated film. (Laminated Films 2 to 10) The hardness index of each adhesive layer was measured and found to be in the range of 400 to 700. (2) Evaluation Table 2 shows the evaluation results of the produced laminated film.

[Table] Example 3 (1) Creation of laminated film The films used in Example 1 were used for PPS-BO and PET-BO. The adhesives used for lamination were Adhesive-1 (“Adcoat” 76P1 manufactured by Toyo Morton Co., Ltd.) used in Example 1 and “Liofol” 3600/6200 manufactured by Henkel Hakusuisha (this adhesive was used as Adhesive-2). ) were used. Nine types of Adhesive-1 were prepared with different mixing ratios of the main agent and the curing agent. Other conditions are as in Example 1.
The same conditions apply. On the other hand, three types of Adhesive-2 were prepared with different mixing ratios of the main agent and the curing agent. The solvent was methyl-ethyl-ketone and the solid content concentration was 45% by weight. The lamination conditions were the same as in Example 112
Created various types of laminated films (Laminated Film 11
~twenty two). (2) Evaluation Table 3 shows the evaluation results of the 12 types of laminated films created. This result shows that the hardness index of the adhesive that can be used in the laminated film of the present invention is in the range of 1 to 3000 mm/min. That is, the hardness index is 1
Even if it is less than mm/min or exceeds 3000 mm/min, there is no effect of improving impact resistance.

〔Effect of the invention〕

The present invention is a laminated film in which a biaxially oriented polyester film or/and PPS-BO is laminated on PPS-BO via an adhesive having a specific hardness, so that the film has excellent heat resistance and impact resistance. was completed.

Claims (1)

[Claims] 1. A laminated film in which biaxially oriented poly-p-phenylene sulfide films are laminated on both sides of a biaxially oriented polyester film via an adhesive, the hardness of the adhesive layer The index is in the range of 1 to 3000, the thickness A of the biaxially oriented poly-p-phenylene sulfide film on one side, and the thickness A of the biaxially oriented poly-p-phenylene sulfide film on the other side.
- A laminated film characterized in that the thickness A' of the phenylene sulfide film and the thickness B of the biaxially oriented polyester film satisfy 0.2≦(A+A′)/B≦3.6.