JPS63242626A - Biaxially oriented poly-p-phenylenesulfide film - Google Patents

Abstract

PURPOSE:To obtain a biaxially oriented poly-p-phenylenesulfide film, which has favorable slip properties and a few bulking projections and insulation defects, by a structure wherein the film contains the specified weight of inactive inorganic particles and has the internal haze per unit thickness and external haze of specified values. CONSTITUTION:The film concerned is a biaxially oriented poly-p- phenylenesulfide film, which contains 0.3-1.5wt.% of inactive inorganic particles and the internal haze per unit thickness of which is 1-3%/mum, and the external haze of which is 5-20%. If the content of the inactive inorganic particle is below 0.3wt.%, the slip properties of the film become poor. If said content exceeds 1.5wt.% insulation defect increases. If the internal haze per unit thickness is below 1%/mum, the slip properties of the film become poor. If said internal haze exceeds 3%/mum, insulation defect increase. If the external haze is below 5%, the slip properties become poor. If said external haze exceeds 20%, the mechanical characteristics of the film become inferior and brittle.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] This invention relates to biaxially oriented poly-p-phenylene sulfide films.

[Prior art and its drawbacks] Biaxially oriented poly-p-phenylene sulfide film is
It has extremely excellent performance in terms of heat resistance, chemical resistance, electrical insulation, dielectric properties, mechanical properties, etc., and is attracting attention as a heat-resistant electrical insulating material.

It has been known that in order to improve the properties of a biaxially oriented poly-p-phenylene sulfite film, inert *a particles are added thereto.

For example, JP-A-55-14968 discloses that inert inorganic particles are added to the polymer during or at the end of the polymerization to adjust the surface roughness of the film, or that insoluble particles used for the polymerization are added to the polymer to adjust the surface roughness of the film. It is disclosed that a certain amount of salt remains. Furthermore, in JP-A No. 60-257510, when a biaxially oriented poly-p-phenylene sulfide film is used as a dielectric of a capacitor, in order to reduce variations in capacitance and dielectric breakdown voltage, and biaxially oriented poly-p with coarse protrusion density adjusted within a certain range.
- A phenylene sulfite film is disclosed, and in order to adjust the fine protrusion density and the coarse protrusion density, if necessary, at any stage before the melt extrusion process, the average particle size of the resin composition is set to 0. 1-1. It is disclosed that s-terminated fine particles are uniformly dispersed. In addition, the special public
-5101 contains inert inorganic particles and its I
T! A biaxially oriented poly-p-phenylene sulfide film is disclosed that has a friction coefficient of 0.75 or less and an average surface roughness of 0.09 pm15+sm or less.

However, when a relatively large amount of inorganic particles are added to a biaxially oriented poly-p-phenylene sulfide film, coarse protrusions are likely to occur in the film due to the inclusion of coarse substances in the particles and coarse particles due to poor dispersion. This results in an insulation defect. Further, a poly-p-phenylene sulfite film containing inorganic particles generates voids around the particles during stretching, resulting in insulation defects. If the amount added is increased in order to increase the protrusion density and improve the slipperiness of the film, insulation defects will further increase due to these voids. Furthermore, if the amount of inorganic particles added is reduced to about 1.5% by weight or less,
Generally, the PJm coefficient increases, making it difficult to handle the film, and when the film is used as a dielectric for a capacitor, insulation defects increase in the pressing process after winding the element.

[Problems to be Solved by the Invention] An object of the present invention is to provide a biaxially oriented poly-p-phenylene sulfide film that has good slip properties but has few coarse protrusions and insulation defects.

[Means for Solving the Problems] As a result of intensive research, the inventors of the present application found that if the internal haze and external haze per film thickness are within a specific range,
This invention was completed by discovering that good slipperiness can be obtained even if the amount of inert inorganic particles is reduced.

That is, this invention contains 0.3% by weight of inert inorganic particles.
Contains 1.5% by weight, internal haze per thickness of 1
%/P garden to 3%/#L Peng, and its external haze is 5
% to 20% biaxially oriented poly-p-phenylene sulfide film.

[Effects of the Invention] Since the biaxially oriented poly-p-phenylene sulfite film of the present invention has a relatively small amount of inert inorganic particles, it has few coarse protrusions and insulation defects, and has good slip properties. The film of the present invention has good slip properties, making it easy to handle, and has few insulation defects, so it exhibits excellent performance when used as a dielectric material for capacitors.

[Specific Description of the Invention] In this specification, poly-p-phenylene sulfite refers to 70 mol% or more (preferably 85 mol%) of repeating units.
If the content of such components is less than 70 mol %, the polymer will be crystalline.

The heat transition temperature, etc. is lowered, and the heat resistance of the resulting film is improved.
Impairs dimensional stability and mechanical properties.

Less than 30 mol% (preferably 15 mol%) of repeating units
(less than), there is no problem even if a unit containing a copolymerizable sulfide bond is included. Examples of such units include (R represents -COOH or -503H, X represents CHl -CHx-1-CHt CH2-1 or -〇- as H3).

This biaxially oriented poly-p-phenylene sulfide film of 1 contains inert inorganic particles of 0.311! presentation% to 1
．． 5% by weight, preferably 0.3% to 1.2% by weight
include. If the content of inert inorganic particles is less than 0.3% by weight, the slipperiness of the film will be poor, and if it exceeds 1.5% by weight, insulation defects will increase. The average particle size of the inert inorganic particles is preferably 0. It is 5JL11 from low, more preferably 0.05p, m to 2 pus. As the inert inorganic particles, any inorganic particles can be used as long as they do not substantially react with poly-p-phenylene sulfide; for example, calcium chloride, silica, kaolin, talc, sulfuric acid. barium, alumina, zinc oxide,
Titanium oxide can be mentioned.

The internal haze per thickness of the biaxially oriented poly-p-phenylene sulfide film of the present invention (internal haze H)/thickness (L) is 1%/final to 3%/final. If the internal haze per thickness is less than 1%/ps, the slipperiness of the film will be poor, and if it exceeds 3%/ps, insulation defects will increase.

Further, the external haze of the biaxially oriented poly-p-phenylene sulfide film of the present invention is from 5% to 20%. External haze is the total haze minus internal haze, and if this is less than 5%, the slipperiness will be poor.
If it exceeds 20%, the mechanical properties of the film will be poor and it will become brittle.

The thickness of the film is preferably 0.3 μl or 6150 M, more preferably 0.3 μl to 25 μl, and more preferably 0.3 μl to 25 μl. S 74m to 10μ garden.

The film may also contain less than 10% by weight of other additives such as other polymers, lubricants, young agents and/or UV absorbers.

The biaxially oriented poly-p-phenylene sulfide film of this invention can be produced as follows.

First, poly-p-phenylene sulfide resin powder produced by a conventional method and inert inorganic particles are mixed at a weight ratio of L, and this resin composition is melted by a conventional method using an extruder such as an extruder. This is extruded and solidified by cooling to obtain an amorphous film. At this time, if desired,
Less than 10% by weight of other polymers, lubricants, R colorants, ultraviolet absorbers, etc. may be added to the resin composition.

Next, this amorphous film is stretched in the longitudinal direction (MD) and the transverse direction (TD). Stretching can be carried out by either sequential biaxial stretching or simultaneous two-machine stretching, but sequential biaxial stretching is preferable.

Film temperature during longitudinal stretching is 97°C to 120°C
The temperature range is preferably from 100°C to 110°C, particularly preferably from 100°C to 110°C. If it is less than 97°C, the resulting film will have insufficient slipperiness, and if it exceeds 120°C, the film formability will deteriorate. The heating time is preferably from 0.2 seconds to 20 seconds, and from 0.2 seconds to 10 seconds.
A range of seconds is particularly preferred.

The heating method is not particularly limited, and any known heating method such as heating rolls, hot air, and radiation heaters can be employed. There are no particular limitations on the stretching method, and it is usually
Performed using multiple rolls. The stretching ratio is not particularly limited, but is 1, for example, from 3.2 times to 4.5 times. The external haze of the biaxially oriented poly-p-phenylene sulfide film can be adjusted by adjusting the temperature and heating time in the f-direction stretching process, and the external haze can be adjusted so that the external haze falls within the range indicated by L. There are 31 conditions.

The stretching ratio is not particularly limited, but for example, 3.0.
It is from 3.8 times to 3.8 times.

Next, the thus stretched film is heat-treated in a conventional manner at, for example, 240°C to 290''C for 1 to 50 seconds to obtain a biaxially stretched poly-p-phenylene sulfite film of the present invention. .

Note that the internal haze depends on the amount of inert inorganic particles added, the particle size, and the degree of dispersion thereof, so these should be adjusted as appropriate within the above range so that the internal haze per thickness is within the range of this invention. select.

[Example] Next, Examples and Comparative Examples of the present invention will be shown.
] The effect of this will be explained in detail.

For each piece, haze, insulation defects, coefficient of friction, strength and elongation were measured as follows.

Haze was measured according to JIS K-6714. Incidentally, the total haze was measured by measuring the test piece in the atmosphere, and the internal haze was measured by immersing the test piece in a Tetralin's quartz cell. Moreover, the external haze was calculated by subtracting the internal haze from the total haze.

Aluminum is vapor-deposited on one side so that the surface resistance of the insulation defective film is about 3 ohms, and the non-evaporated side is placed on a metal mirror plate facing down, and the film thickness is 15 ohms per end of the film between the metal plate and the vapor-deposited surface.
Apply a DC voltage of 0v.

The number of locations where dielectric breakdown occurred was counted, and the number was converted to the number per area of the film, which was used as an index of insulation defects.

Coefficient of Friction According to the ASTM D-113948 method, the coefficient of static friction between film surfaces was measured in an environment of 20°C and 65$RI+.

Strength and elongation JIS C-2318 method, 20°C, 65! R1+
The "t' measurement was carried out under the following environment.

Example 1, Comparative Examples 1 and 2 Average particle size 1. OJLll calcium carbonate, respectively.
, t, o, s, or 2.0% by weight added poly-p
- A phenylene sulfide composition was melt-extruded and cooled and solidified in a cast drum E to obtain an amorphous film.
After being brought into contact with rolls heated to 105°C, it was stretched 3.6 times in the machine direction (MO) between rolls with two different circumferential speeds, and stretched 3.4 times in the width direction (TD) at 100°C with a tenter. ,2
A constant length heat treatment was performed at 60° C. for 5 seconds to obtain a biaxially oriented poly-p-phenylene sulfite film having a thickness of 2 mm. This film was measured for internal haze, external haze, coefficient of friction, and insulation defects. The results are shown in Table 1.

1.5% by weight of silica with different average particle sizes by the method of Example 1
3.5 µm thick films with different internal hazes were prepared, and their friction coefficients and insulation defects were measured. The results are shown in Table 2.

By the method of Example 1, films with different external hazes and thicknesses of 6-6 were produced by changing the MD stretching temperature, and their friction coefficients, strength, and elongation were measured. The results are shown in Table 3.

Table 3

Claims (1)

[Claims] Contains 0.3% to 1.5% by weight of inert inorganic particles,
Internal haze per thickness is 1%/μm to 3%/μm
A biaxially oriented poly-p-phenylene sulfide film having an external haze of from 5% to 20%.