JPH01101336A - Biaxially oriented polyether ether ketone film - Google Patents

Abstract

PURPOSE:To obtain the titled film outstanding in surface flatness, slipperiness, traveling durability, electrical insulating characteristics, heat resistance etc., to be used in e.g. capacitors, by incorporating a thermoplastic polyether ether ketone with specific silicone resin fine particles. CONSTITUTION:The objective film with low repeated coefficient of friction, thus excellent in slipperiness, can be obtained by incorporating (A) a thermoplastic polyether ether ketone with (B) 0.005-3.0wt.%, based on the component A, of silicone resin fine particles having constitution of formula RX(SiO2)X/2 (R is 1-7C hydrocarbon group; X is 1-1.2), with the f-value falling between 0.4 and pi/6 expressed by the equation; f=V/D<3> [V is average volume per particle (mum<3>); D is average maximum size (mum)] and average size of 0.01-4mum.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a biaxially oriented polyetheretherketone film, more specifically, it contains silicone resin fine particles, has a flat surface, has good slip properties, and has good running durability.

This invention relates to a biaxially oriented polyetheretherketone film that has excellent insulation properties and heat resistance.

[Prior Art] Biaxially oriented polyethylene terephthalate films have been widely used in industrial applications because of their excellent mechanical properties, electrical properties, heat resistance, chemical resistance, and the like.

However, in recent years, the required properties of films have increased depending on the application, and there are limits to the properties of biaxially oriented polyethylene terephthalate films, so there is a demand for films with even more excellent properties. For example, biaxially oriented polyethylene terephthalate film has a long-term heat resistance of class E (long-term heat resistance fl: 125°C) to class 8 (long-term heat resistance fl: 135°C).
0° C.), and when used as a motor insulation or disconnection covering material, there is a problem in that miniaturization of motors is restricted due to this long-term heat resistance. Furthermore, when the above film is used for capacitor applications, the dielectric loss tangent increases from around 85° C., which limits the operating temperature. Furthermore, when the above-mentioned film is used as a flexible printed circuit board, solder heat resistance becomes a problem, and its development is limited. For these reasons, there is a demand for films with even better heat resistance.

By the way, thermoplastic boriether ether ketone is known as a crystalline thermoplastic polymer having toughness and excellent heat resistance (Japanese Patent Publication No. 32642/1983, Japanese Patent Publication No. 61/1989).
No. 10486), the development of this film has been studied and proposed. For example, in JP-A-57-137116@publication,
Thermoplastic polyetheretherketone film is used in fields that take advantage of its heat resistance, namely insulating film for motors and insulating film for transformers.

The paper describes a method for producing a uniaxially oriented film using a rolling method, which is expected to be used in insulating films for capacitors, flexible printed circuit boards, etc.
It is explained that inorganic fillers such as talc, basic magnesium carbonate, alumina, alumina hydrate, barium sulfate, calcium sulfate, mica powder, zinc white, titanium 81ide, and carbon black may be added.

JP-A-58-63417 describes a method for producing an isotropic biaxially oriented polyetheretherketone film.

JP-A No. 60-93625 describes a polyetheretherketone film for perpendicular magnetization which is oriented in two wheels by a rolling method.

JP-A No. 60-187928 discloses that the stress at 5% elongation in both the longitudinal direction and the direction perpendicular thereto is 13? cy/
- or more, the initial elastic modulus in at least one direction is 60ONy/-
A magnetic recording material based on a biaxially oriented polyetherketone (or polyetheretherketone) film having a heat shrinkage rate of 4% or less in the longitudinal direction and perpendicular direction at 180° C. is described, and the polymer It is explained that a lubricant such as matting titanium dioxide, particulate silica, or china clay may be contained therein.

JP-A-60-189421 discloses a polyetherketone (or polyetheretherketone) containing inorganic particles, which has a surface roughness Ra of o, ooa~0.090 and a dynamic friction coefficient μd of 0.12~0.090. 0.50, the inorganic particles include magnesium oxide, zinc oxide, magnesium carbonate, magnesium phosphate, calcium sulfate, barium sulfate, aluminum oxide, silicon dioxide.

It is explained that inorganic oxides such as titanium oxide, kaolin, and diatomaceous earth, inorganic salts, aluminosilicates, and carbon black can be mentioned.

JP-A No. 61-37418 discloses that 100 parts of polyetheretherketone is mixed with 0.01 to 10 parts of an iridium-free filler.
A biaxially oriented easily slippery thermoplastic polyetheretherketone film is described, which is prepared by forming a biaxially oriented composition containing the following inorganic fillers: talc, silica, kaolin, calcined kaolin, mica, aerosil, thyroid, One or more types of fibers such as calcium carbonate and potassium titanate fibers are appropriately selected and used, and it is explained that fine particles with an average particle size of 5 μm or less are particularly preferable.

However, according to the research results of the present inventors, these biaxially oriented polyether ether ketone films have voids around the inorganic particles in the film, which improves running durability, insulation defect abnormality rate, and dielectric breakdown. It became clear that there were issues that needed to be improved, such as in terms of It was also revealed that inorganic particles were poorly dispersed in the film.

[Object of the Invention] An object of the present invention is to provide a two-wheel oriented polyetheretherketone film that has a flat surface, excellent slip properties, running durability, insulation properties, etc., and excellent heat resistance.

Another object of the present invention is to provide biaxially oriented polyether ether which has a large number of fine protrusions derived from silicone resin particles on the film surface, has a flat surface, and has excellent slip properties, running durability, insulation properties, etc. Our goal is to provide a ketone film.

Further objects and advantages of the present invention will become apparent from the description below.

[Structures and Effects of the Invention] According to the present invention, the above-mentioned objects and advantages of the present invention are firstly achieved by: (I) a thermoplastic polyetheretherketone; and (II) (a) the following formula (A) Rx St 02 -x/2...(A) Here,
R is a hydrocarbon group having 1 to 7 carbon atoms, and X is a number of 1 to 1.2, and has a composition represented by (b) the following formula (B) f = V/D3... (B) where ■ is the average volume of the particles (μm') and D is the average maximum diameter of the particles (μm')
(C) silicone resin fine particles having an average particle size of 0.01 to 4 μm; This is accomplished with a biaxially oriented polyetheretherketone film formed from an intimate mixture of ~3.0% by weight (based on thermoplastic polyetheretherketone).

The thermoplastic polyetheretherketone in the present invention is a polymer consisting of the above structural unit and other structural units.

Examples of other structural units include the following. In the above structural unit, A is a direct bond, oxygen, -8Oz +, -co- or a divalent lower aliphatic hydrocarbon group, and Q and Q' may be the same or different <-CO - or -802-, and n is O
Or 1. These polymers are
Publication No. 42, Japanese Patent Publication No. 61-10486, Japanese Patent Publication No. 5
7-tayttj publication etc.

Thermoplastic polyether ether ketone may be blended with resins such as polyarylene polyether, polysulfone, polyarylate, polyester, polycarbonate, etc. for the purpose of improving fluidity, and may also be blended with stabilizers, antioxidants, and ultraviolet absorbers. It may also contain additives such as.

As mentioned above, the thermoplastic polyetheretherketone is
They are known per se and can be produced by methods known per se.

The above thermoplastic polyether ether ketone has an apparent melt viscosity of 380° C. and an apparent shear rate of 200 se.
The condition c' is preferably in the range of 500 voids to 10000 voids, more preferably 1000 voids to 5000 voids, from the viewpoint of film formability and film properties.

The biaxially oriented polyetheretherketone film of the present invention has a large number of fine protrusions on the film surface, as is clear from the later explanation of Ra, which defines the flatness of the film surface.

According to the invention, these large numbers of microscopic protrusions originate from a large number of substantially inert solid fine particles dispersed in the thermoplastic polyetheretherketone.

In the present invention, the silicone resin fine particles (II) have the following formula (A> Rx Si 02-x /2 = (A), where R is a hydrocarbon group having 1 to 7 carbon atoms, and x is 1
It has a composition expressed as ~1.2.

R in the above two formulas (A) is a hydrocarbon group having 1 to 7 carbon atoms, such as an alkyl group having 1 to 7 carbon atoms.

A phenyl group or a tolyl group is preferred. Carbon number 1"~
The alkyl group of 7 may be linear or branched, such as methyl, ethyl, n-propyl, 1so
-propyl, n-butyl, 13o-butyl, tert
-butyl, n-pentyl, n-heptyl and the like.

Among these, R is preferably methyl and phenyl, with methyl being particularly preferred.

X in the above formula (A) is a number from 1 to 1.2.

When X is 1 in the above formula (A), the above formula (A)
can be represented by the following formula <A)-1 R3iO/, r...(A)-1 where the definition of R is the same as above.

The composition of the above formula (A>-1) originates from the following structural part: -0-8i -0- in the three-dimensional polymer chain structure of the silicone resin.

Moreover, when X is 1.2 in the above formula (A), the above formula<A) becomes the following formula<A) -2R7λ S f O/
, t...(A)-2 Here, the definition of R is the same as above.

The composition of the above formula (A)-2 is the structure 0.
8 mol and 0.2 mol of the structure represented by the following formula (A)' R2Si O...(A)' where the definition of R is the same as above.

The above formula (A) is derived from the following structural part in the three-dimensional polymer chain of silicone resin: -o-sr -o- (2).

As understood from the above explanation, the above formula (A
For example, the composition of > may consist essentially only of the structure of the above formula (A,)-1, or the structure of the above formula (A)-1 and the structure of the above formula (A>-2 may be randomly arranged in an appropriate ratio) It can be seen that the structure consists of a structure that coexists in a bonded state.

The silicone resin particles of the present invention preferably have the above formula (
A>, X has a value between 1 and 1.1.

Further, the silicone resin particles (n) of the present invention can be expressed by the following formula (B
) f = V/D3 (B) where ■ is the average volume per particle (μ7FL3), and D is the average maximum particle diameter (μm) of the particles.The volume defined by The shape factor <f 2 ) is thicker than 0.4 and less than or equal to π/6.

In the above definition, the average maximum particle diameter of the particles of D should be understood as the distance having the maximum length among the distances between two points where any straight line that crosses the particle intersects the circumference of the particle.

The preferred value of the silicone resin particles of the present invention is 0.44.
~π/6, and a more preferable value of f is 0.48~π/6.
It is 6. A particle whose value of f is π/6 is a true sphere. When silicone resin particles having an f value smaller than the lower limit are used, the film surface characteristics a and IIm become extremely difficult.

The silicone resin particles used in the present invention further have 0.
It has an average particle size of 0.01 to 4 μm. Average particle size is 0.
When particles smaller than 01μ tiles are used, the effect of improving slipperiness and abrasion resistance is insufficient;
If particles larger than μm are used, only a film with insufficient planar flatness can be obtained.

The average particle size preferably lies in a value of 0.05 to 3 μm.

It is understood that the old average particle size here is the diameter at the 50% point of integration of the isovalue particle size distribution calculated based on Stokes' equation.

The silicone resin particles used in the present invention can be prepared, for example, by the following formula (%), where R is a hydrocarbon group having 1 to 7 carbon atoms, and R
' is a lower alkyl group A trialkoxysilane or a partially hydrolyzed condensate thereof is treated in the presence of ammonia or an amine such as methylamine, dimethylamine, ethylenediamine, etc.
It can be produced by hydrolysis and condensation under stirring. According to the above method using the above starting material,
Silicone resin particles having the composition represented by the above formula (A)-1 can be manufactured.

R2S! (OR'>2 Here, the definitions of R and R' are the same as above. If dialkoxysilane represented by is used together with the above trialkoxysilane and the above method is followed, the above formula (A
)-2 can be produced.

The silicone resin particles used in the present invention are expressed by the following formula % where γ is the particle size ratio and 025 is the integrated fine particle ff
1ffi is the particle size when it is 25% of the total mold mouth, and Dye is the particle size when the integrated weight of fine particles is 15% of the total Ifli, however, the proportion of Jifeng heavy group is large. The particle size ratio (γ), which is measured from the particle size, is preferably in the range of 1 to 1.4. This particle size ratio is more preferably 1 to 1.
．． It is in the range of 3, particularly preferably in the range of 1 to 1.3, particularly preferably in the range of 1 to 1.15.

The intimate mixture of thermoplastic polyetheretherketone (I) and silicone resin microparticles (II) forming the film of the present invention comprises:
The fine particles (II) are contained in an amount of 0.005 to 3.0% by weight (based on the thermoplastic polyetheretherketone).

If the amount of the fine particles (II) is less than 0.005% by weight, the effect of improving the slipperiness and abrasion resistance of the film is insufficient,
On the other hand, if it exceeds 3.0% by weight, the flatness of the film decreases.

The fine particles (IF) (7) ffi 0.01 to 0.5
ff1m% (based on thermoplastic polyetheretherketone) is preferred.

As described above, the silicone resin fine particles used in the present invention impart surface flatness, WJ resistance, and abrasion resistance to the polyetheretherketone film. In particular, according to the research conducted by the present inventors, it is clear that the reason for the excellent abrasion resistance is that the silicone resin fine particles have a very high affinity with the polyetheretherketone in which they are mixed. It was done.

That is, when the surface of the film of the present invention containing the silicone resin fine particles was ion-etched to expose the silicone resin fine particles in the film and the surface was observed with a scanning electron microscope, it was found that the surrounding surface of the silicone resin fine particles was polyether ether. being in substantial contact with a ketone substrate;
In other words, little or no voids are observed between the surrounding surface and the polyetheretherketone matrix.

Furthermore, the fact that the silicone resin fine particles of the film of the present invention have a high affinity with the polyetheretherketone substrate can be evaluated using another measure, the void ratio (ratio of the long diameter of the particles to the long diameter of the voids), which will be defined later. Substantially all of the films of the present invention have a void ratio of 1.0 to 1.5, most of them have a void ratio of 1.0 to 1.3, and further have a void ratio of 1.0 to 1. It became clear that those with a value of .15 accounted for the main part.

The biaxially oriented polyetheretherketone film of the present invention, which has few voids and a void ratio close to 1.0, is particularly excellent in abrasion resistance and dielectric breakdown voltage.

In general, thermoplastic polyetheretherketones and inert particles (l-agents) have no affinity. Therefore, when an unstretched film of melt-formed polyetheretherketone is stretched with two wheels, peeling occurs at the boundary between the fine particles and the polyetheretherketone, and voids are usually formed around the fine particles.

The larger the particle size, the closer the shape is to a spherical shape, the more difficult the particle is to deform as a single particle, the larger the stretching area ratio when stretching an unstretched film, and the lower the temperature. It tends to get bigger the more you do it. The larger the voids become, the more gradual the shape of the protrusions becomes, increasing the coefficient of friction, which also causes the voids in the biaxially oriented polyetheretherketone film to fall off during repeated use. This reduces durability and causes shavings.

As described above, in the case of conventional inorganic inert lubricants, the voids around the lubricant are quite large, and in high-strength polyetheretherketone films, these voids become even larger, resulting in problems such as the calendering process of magnetic tape, etc. , the abrasion resistance is usually poor during the machining process. Also, in capacitors, disconnection leads to a decrease in breakdown voltage.

As mentioned above, the silicone resin fine particles used in the present invention have a high affinity with the polyetheretherketone substrate, and therefore voids are less likely to occur around the particles.

Therefore, when using the above-mentioned silicone resin fine particles, the frequency of generating voids, which generally becomes larger as the particles become larger, can be suppressed to a low level. At the same time, relatively small particles with a low rate of void generation are used, and while having the advantage of using two types of particles, it has excellent runnability, abrasion resistance, fatigue resistance, electrical insulation, and transparency. It has become clear that it is possible to provide an excellent film.

That is, such a biaxially oriented polyetheretherketone film comprises (I) a thermoplastic polyetheretherketone, (■
) (1) Having the composition represented by the above formula (A),
The volumetric shape factor (') defined by the above formula (B) is 0.4
0.005 to 1% by weight of silicone resin microparticles (based on thermoplastic polyetheretherketone) which are larger than π/6 and have an average particle size of +c+ 0.3 to 4 μm and (III) 0.01 0.005 to 1% by weight (based on thermoplastic polyetheretherketone) of inert microparticles having an average particle size of ~1 μm and whose average particle size is smaller than the average particle size of the silicone resin microparticles. It is a biaxially oriented film formed from a mixture of

The thermoplastic polyether ether ketone (I>) and the silicone resin fine particles (If, l are as described above.

However, as the silicone resin fine particles, relatively large particles with an average particle size of 0.3 to 4 μm are used in this case.

As the inert fine particles (III) whose average particle size is smaller than that of the silicone resin fine particles, those which are inert and insoluble in the thermoplastic polyetheretherketone and are solid at room temperature are used. These may be externally added particles or internally generated particles. Further, for example, a metal salt of an organic acid may be used, or an inorganic substance may be used. Preferred inert particles (A> include: 1) calcium carbonate, 2) silicon dioxide (hydrate,
(including diatomaceous earth, silica sand, 1 quartz, etc.), alumina, 081
Silicates (e.g. amorphous or crystalline clay minerals, aluminosilicate compounds) containing 30% by weight or more of
(including fired products and hydrated products), warm asbestos, zircon, fly ash, etc.), ■Mg, Zn.

Zr and T1 oxides, ■Ca and Ba sulfates, ■L
i, l'4a and Ca phosphates (including monohydrogen salts and dihydrogen salts), ■1-t, Na and K benzoates, ■
Terephthalates of Ca, Ba, Zn and Mn, @!
vlo, Ca, Ba, Zn, Cd,
Pb.

Sr, Mn, Fe, co and Ni titanates, QBa
and pb chromate, O carbon (e.g. carbon black, graphite, etc.), ■Glass (e.g. glass powder, glass beads, etc.), ■MoCO3, ■Fluorstone, and @Z
An example is nS.

Particularly preferred are anhydrous silicic acid, hydrated silicic acid, aluminum oxide, aluminum silicate (including fired products, hydrates, etc.), phosphorus R1 lithium, trilithium phosphate, sodium phosphate, and calcium phosphate.

Barium sulfate, titanium oxide, lithium benzoate.

Examples include double salts (including hydrates) of these compounds, glass powder, clay (including kaolin, bentonite, clay, etc.), talc, diatomaceous earth, and the like. Such inert fine particles (I
Among [[), externally added particles are particularly preferred.

The silicone resin fine particles (II) have an average particle size of 0.3 to 4 μm. Preferably 0.3 to 2 μm.

Particularly preferably, they have an average particle size of 0.5 to 1.5 μm.

In addition, the inert particles (1) have an average particle size of 0.01 to 1 μm, but are smaller than the average particle size of the silicone resin fine particles (It), and are used in combination with t1.

The inert fine particles (III) preferably have a particle size of 0.05 to 0.0.
Average particle size of 8 μm, more preferably 0.1-0.5 μm
It has an average particle size of

The content of the inert fine particles (1) is 0.005 to 1% by weight based on the thermoplastic polyetheretherketone, but
．． 01 to 1% by weight, more preferably 0.01 to 0.5% by weight, especially 0.05 to 0.3% by weight. - The content of silicone resin fine particles (n) is 0.005 to 1% by weight based on thermoplastic polyetheretherketone, but 0.0
1 to 1% by weight, more preferably 0.04 to 0.5, especially 0.1 to
0.5% by weight is preferred.

Inert fine particles (I[) or silicone resin fine particles (II)
If the content of - is too small, the synergistic effect of using two types of particles, large and small, cannot be obtained, and properties such as runnability, wear resistance, fatigue resistance, crushability, and end surface alignment are deteriorated, which is undesirable. On the other hand, if the content of inert particles (1) is too large, voids due to small particles in the polymer tend to occur more frequently, resulting in poor wear resistance, fatigue resistance, crushability,
insulation voltage.

Transparency etc. decreases.

Furthermore, if the content of silicone resin fine particles <II) is too large, the surface of the film becomes too rough and, for example, the electromagnetic conversion characteristics of a magnetic tape deteriorate, which is not preferable.

When producing the biaxially oriented film of the present invention, in order to intimately mix silicone resin fine particles or their inert fine particles with polyetheretherketone, these fine particles are
Before or during the polymerization of the polyether ether ketone, it is sufficiently kneaded with the polyether ether ketone in a polymerization kettle, in an extruder when polymerization is completed and pelletized, or in an extruder when melt extruding into a sheet. Bye.

The polyetheretherketone film of the present invention has, for example, a melting point (T+a: "C) +30°C or Ts +9
0) Melt extrude thermoplastic polyetheretherketone at a temperature of 'c to obtain an unstretched film.
~(Till +45) 'C temperature (Tg: glass transition temperature of polyetheretherketone) 1.5
Stretched by a factor of at least 2.5 times, especially 2.5 times or more, and then in a direction perpendicular to the above stretching direction (if the -th stage stretching is in the vertical direction, the second stage stretching is in the horizontal direction) (T(1+10)~ (T(1+
40) It can be produced by stretching at a temperature of 2.5 to 5.0 times. In this case, the area stretching ratio is preferably 4 times or more, more preferably 6 times or more. The stretching means may be either simultaneous two-wheel stretching or sequential two-wheel stretching.

Furthermore, the biaxially oriented film is ('l, +70)'C~To
It can be heat-set at a temperature of + ('C). For example, for polyetheretherketone film, 20
It is preferable to heat set at 0 to 350°C.

The heat setting time is, for example, 1 to 120 seconds.

The thickness of the polyetheretherketone film is 1 to 2
50 μm1, more preferably 1 to 125 μm1, particularly 1 to 75 μm.

The biaxially oriented polyether ether ketone film of the present invention has uniform uneven surface characteristics, excellent slipperiness, heat resistance, and abrasion resistance, and is characterized by significantly less generation of scratches, white powder, etc.

This biaxially oriented polyetheretherketone film can be widely used in various applications by taking advantage of these properties. For example, when used as electrical insulation materials, motor insulation, and wire coatings, excellent heat resistance and processability can be obtained. Furthermore, when used in capacitor applications, it is possible to obtain high-quality capacitors that can be used at high temperatures due to its low coefficient of friction, excellent winding properties, low crushing load, and excellent heat resistance. In addition, when used in FPC (flexible printed circuit) applications, FPC with excellent solder resistance
It is possible to obtain In addition, when used as a base film for magnetic recording such as video, audio, and computers, it has excellent electromagnetic conversion characteristics, slipperiness,
Driving durability etc. can be obtained. In particular, it is suitable as a base film for vacuum evaporation or sputtering, which is obtained by applying a metal thin film to a base film, due to its heat resistance.

Biaxially oriented polyetheretherketone film is preferable for use in electrical disconnections, capacitors, FPCs, and metal thin film magnetic recording media, but coating! For magnetic recording media, for vapor deposition,
It can also be widely applied as a base film for dry transfer, etc.

Note that various physical property values and characteristics in the present invention were measured and defined as follows.

(1) Average particle size (OP) Shimadzu CP-50 Centrifugal Particle Size Analyzer (CentrifugalP)
It was measured using an article tze analyzer).

The particle size corresponding to 50 mass percent was read from the integrated curve of particles of each particle size and their abundance calculated based on the obtained centrifugal sedimentation curve, and this value was taken as the above average particle size (8
00k "Particle size measurement technology" published by Nikkan Kogyo Shimbun, 197
5th Year 1, pp. 242-247).

(2) Particle size distribution ratio (γ) Based on the centrifugal sedimentation curve obtained in the measurement of the average particle size of particles, calculate and draw the product curve of particles of each particle size and their abundance, and W4 rods of particles integrated from the larger diameter! f
Particle size corresponding to fi of 257 percent (D25)
Then, read the particle diameter (D7?) whose cumulative weight corresponds to 75 mass percent, and divide the former value by the latter value (Dδ/D) to calculate the particle size distribution ratio (γ) of each particle. .

(3) Film friction coefficient (μk) In an environment of temperature 20°C and humidity 60%, a film cut to a width of 172 inches was held at an angle of θ-152/ by a fixed rod (surface roughness 0.3 μm).
20 per minute with contact at 180π radians (152°)
Move at a speed of 0α (rI!il). When the tension controller is adjusted so that the inlet tension T1 is 35 g, the exit tension (T+:g> is detected by the exit tension detector after the film has traveled 90 m. , calculate the running friction coefficient μk using the following formula.

μk = (2,303/θ) log (T2/
TI ) (4) Film surface flatness CLA (Center Line Averaa)
- Centerline average roughness) Measured according to JIS B 0601. Stylus type surface roughness meter (SUR) manufactured by Tokyo Seimitsu Co., Ltd.
FCOM3B), needle radius 2μ, load 0.07
A chart (film surface roughness curve) was drawn under the following conditions. A part of the measurement length is extracted from the film surface roughness curve in the direction of its center line, and the center line of this extracted part is taken as the X axis, and the direction of vertical magnification is taken as the Y axis, and the roughness curve Y=
When expressed as f(x), the value (Ra
: μm) is defined as the flatness of the film surface.

Ra - (1/L) fLIf (x) ldx In the present invention, eight measurements were taken with a reference length of 0.25 M, and Ra was expressed as the average value of five, excluding three from the largest value.

(5) Void ratio sample film small piece was fixed on a sample stage for a scanning electron microscope, and sputtering equipment ff (JF C-11 manufactured by JEOL Ltd.
The surface of the film was subjected to ion etching using a Model 00 ion sputtering apparatus under the following conditions. Place the sample stand in the Pelger and heat it to about 10' Torr.
The degree of vacuum was increased to a vacuum state of 0.25 KV and current i2. Ion etching was performed at smA for about 10 minutes. Furthermore, gold sputtering was performed on the film surface using the same apparatus to form a gold wJWA layer of approximately 200 layers, and measurement was performed using a scanning electron microscope at a magnification of 10,000 to 30,000 times. Note that voids were measured only for lubricants with a particle size of 0.3 μm or more.

(6) Haze (haze) The haze of the film was determined according to JIS-674 using an integrating sphere HTR meter manufactured by Nippon Seimitsu Kogaku Co., Ltd.

(7) Volume shape factor <f) Photographs of particles are taken with a scanning electron microscope in 10 fields of view at a magnification of, for example, 5000 times, and the average value of the maximum diameter is calculated using, for example, an image analysis processing device Luzex 500 (manufactured by Nippon Regi Nilator). Measurements were made for each visual field, and the average value of the 10 visual fields was determined and designated as D.

The average volume of the particles (■-(π/6) d3) was determined from the average particle diameter d of the particles determined in the above section (1) of the measurement method, and the shape factor f was calculated using the following formula.

f = V/D'' In the formula, ■ represents the average volume of the particles (μm'), and D represents the average maximum particle diameter (μm) of the particles.

(8) Dielectric breakdown voltage and dielectric breakdown abnormality rate Dielectric breakdown voltage is measured according to the method shown in JIS-C-2318. n-
An average value of 100 is adopted, and the ratio (%) of those exhibiting a value of 1/3 or less of this average value is defined as the dielectric breakdown abnormality rate.

(9) Evaluation of element end face irregularities and element end face shape after flattening A 10μ film was deposited with aluminum and 2G1111
The 1-width slit is wound around a core with an outer diameter of 3 g at a tension of 4.
09. An element was wound to a length of 4 m at a winding speed of 30c11/Sec. Regarding the unevenness of the element end faces, the end face was all perfectly aligned, and O was the end face. Some of the end faces were slightly uneven. A case where the degree of damage is small and causes no practical problem is marked as Δ, and a case where it cannot be used is marked as ×.

When the element is flattened by pressing, the shape of the end face of the element after flattening is evaluated as 0.0. A film in which a slight gap is observed in some parts but causes no practical problem is marked as Δ, and a case in which the film is unusable due to non-uniform crushing and gaps between the film layers is marked as ×.

(g)) The agglomerated film of the lubricant was magnified 20 times under polarized light, and the number of agglomerated lubricants of 25μ or more that glowed in the dark field with a polarizing plate orthogonally crossed was evaluated. The measurement area is 10ci, and the number of pieces per cd is 0.10 to 3.
0 items were evaluated as Δ, and 30 or more items were evaluated as ×.

Comprehensive evaluation of CIl+ capacitors Comprehensive evaluation of handling workability such as crushability, single-turning property, vapor deposition processability, electrical properties such as dielectric breakdown voltage and dielectric breakdown abnormality rate, and ◎ is good for all, and ◎ is slightly poor. Those that have a surface but have no practical problems are designated as O0, those that have practical problems are designated as Δ, and those that cannot withstand use are designated as ×.

[Example] The present invention will be further explained below with reference to Examples.

Examples 1 to 7 Thermoplastic polyetheretherketone (manufactured by IC1: Polyetheretherketone 380G) was mixed with silicone resin fine particles and inert particles in the proportions shown in Table 1, and after blending, it was extruded at 380°C. Extruded and cast onto a casting drum maintained at a temperature of 80°C.
Create an unstretched film of μ and stretch it in the longitudinal direction at 160℃
Stretch it 2.7 times, then feed it to a tenter and stretch it 16
It was stretched 3 degrees 5 times at 0°C and heat-set at 250°C for 30 seconds. Table 1 shows the properties of these films.

Comparative Examples 1 to 3 Comparative Examples 1 to 3 The same polymers as in Example 1 were used, except that only the lubricant was changed to those shown in Table 1.

The properties of these films are shown in Table-1.

The silicone resin fine particles shown in Table 1 have the average particle diameter shown in Table 1, and have a volume shape coefficient of 0.52 to 0.4.
8 and a particle size distribution ratio (γ) of 1.1 to 2.0. (Composition: CH3SiO)t) From the results in Table 1, it can be seen that the film of the present invention has a flat surface, a small coefficient of friction in repeated cycles, and excellent slipperiness. Furthermore, the film of the present invention has less agglomeration of lubricant, and is found to be very excellent when viewed as a film for capacitors.

Patent Applicant Teijin Ltd. Representative Patent Attorney 1) Jun Hirogo Par “5, Procedural Amendment January/θ, 1989

Claims (1)

[Claims] 1. (I) Thermoplastic polyether ether ketone, and (II) (a) the following formula (A) R_xSiO_2_-_x_/_2...(A) where R has 1 to 1 carbon atoms 7 hydrocarbon group, and x is a number from 1 to 1.2, and has a composition represented by (b) the following formula (B) f=V/D^3...(B) where where V is the average volume per particle (μm^3) and D is the average maximum particle diameter (μm) of the particles.The volume shape factor (f) defined by is greater than 0.4 and π /6 or less, and (c) from an intimate mixture consisting of 0.005 to 3.0% by weight (based on thermoplastic polyetheretherketone) of silicone resin microparticles having an average particle size of 0.01 to 4 μm. Biaxially oriented polyetheretherketone film formed. 2. The film according to claim 1, wherein in the above formula (A), R is a linear or branched alkyl group having 1 to 7 carbon atoms, a phenyl group, or a tolyl group. 3. The film according to claim 1, wherein in the above formula (A), x is a number from 1 to 1.1. 4. The film according to claim 1, having a volumetric shape factor (f) of between 0.44 and π/6. 5. The film according to claim 1, wherein the average particle size is between 0.05 and 3 μm. 6. The amount of silicone resin fine particles is 0.01 to 1.5% by weight
The film according to claim 1, which is (relative to thermoplastic polyetheretherketone). 7. The silicone resin fine particles have the following formula (C) γ=D_2
_5/D_7_5...(C) Here, D_2_5 is the average particle diameter (μm) when the cumulative weight of particles is 25%, and D_7_5 is the average particle diameter (μm) when the cumulative weight of particles is 75%. 2. A film according to claim 1, having a particle size distribution ratio (γ) of between 1 and 1.4. 8. (I) Thermoplastic polyetheretherketone, (II) (a) has a composition represented by the above formula (A), (b) has a volume shape factor (f) defined by the above formula (B) 0.005 to 3.0% by weight of silicone resin fine particles (based on thermoplastic polyetheretherketone) having an average particle size of greater than 0.4 and less than or equal to π/6, and (c) 0.3 to 4 μm. and (III) inert fine particles having an average particle size of 0.01 to 1 μm and smaller than the average particle size of the silicone resin fine particles.
．． Biaxially oriented polyetheretherketone film formed from an intimate mixture of 0% by weight (based on thermoplastic polyetheretherketone).