JPH04123028A - Shutter blade with superior slidability - Google Patents

Abstract

PURPOSE:To improve the slidability and to reduce the light reflection factor by using a carbon fiber-reinforced resin(CFRP) sheet formed on a specific uneven surface as a base material and forming a resin film which contains a sliding agent on the uneven surface. CONSTITUTION:The surface of the CFRP sheet is made uneven (rough surface) and the sheet is used as the base material sheet. The center line mean roughness of the CFRP sheet is 0.4 - 2.0 mum and, preferably, 0.5 - 1.5 mum. Then the rough surface of the CFRP sheet is coated with resin paint which contains the sliding agent and a heat treatment is carried out to form a film which contains the sliding agent. Consequently, the low-light-resflection-factor shutter blade which has superior slidability and conductivity and can easily be put in fast operation and is hardly charged electrostatically is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a shutter blade made of carbon fiber reinforced resin (hereinafter also referred to as CFRP) and having excellent sliding properties.

(Prior art and its problems) Materials suitable for high-speed operation are strongly desired for camera shutter blades, and in order to meet this demand, materials that are lightweight,
Moreover, a material with high bending rigidity is required. CFRP sheet is an excellent material that meets this demand, and is disclosed in Japanese Patent Application Laid-open Nos. 59-61827 and 63-17435.
JP-A-1-316728 and the like propose a shutter blade made of a CFRP sheet.

In the case of CFRP sheets, it is difficult to obtain complete light-shielding properties using only carbon fibers, and areas with no light-shielding properties such as pinholes are likely to occur. ) is being dispersed to improve light-shielding properties.

Although such CFRP sheets have the advantages of high bending rigidity and light weight, they are not satisfactory as shutter blades as they are, and the surface has abrasion resistance, scratch resistance, lubricity, It has also been proposed to apply a lubricating black coating to improve properties such as light-shielding properties and aesthetic appearance.

However, such a shutter blade made of CFRP cannot be operated at high speed (for example, shutter speed 1/1).
8,000 seconds), and the reduction in light reflectance was also insufficient, so it was still not satisfactory.

(Invention Section M) The present invention provides carbon fibers having excellent sliding properties and low light reflectance.
The challenge is to make FRP Sharasha starter blades.

(Means for Solving the Problems) As a result of repeated research in order to solve the above problems, the present inventors used a CFRP sheet with a specific uneven surface as a shutter blade base material. It was discovered that the above problem could be solved by coating the uneven surface with a resin paint containing a sliding agent, and the present invention was completed.

That is, according to the present invention, a black light-shielding carbon fiber reinforced resin sheet formed on an uneven surface having a center line average roughness in the range of 0.4 to 2.0 pm is used as a base material, and the uneven surface is Provided is a shutter blade with excellent sliding properties formed by forming a resin coating containing a sliding agent.

In the present invention, CFRP is used as the jitter blade base material.
Use a sheet. CF as the base material for this shutter blade
RP sheets are conventionally known. A preferred CFRP sheet used in the present invention is a composite sheet formed by laminating a plurality of prepreg sheets formed by impregnating carbon fibers with a resin in which a black pigment (carbon black, aniline black, etc.) is dispersed, and heating and pressurizing the sheets. It is molded into. In this case, it is preferable to use prepreg sheets with a basis weight of 10 to 100 g/m, and the orientation direction of carbon fibers when laminating prepreg sheets is o°/9o.
Preferably, the angles are perpendicular to each other, such as at 10 degrees. As the matrix resin, thermosetting resins such as epoxy resins, unsaturated polyester resins, and phenol resins, and thermoplastic resins such as polyester resins and polyamide resins are used. The thickness of the CFRP sheet is 50 to 150. That's about it.

In the present invention, the surface of this CFRP sheet is an uneven surface (
It is formed into a rough surface and used as a base sheet for shutter blades. As a method for roughening the CFRP sheet, a sandblasting method can be applied, and preferably, the surface of the plurality of CFRP sheets can be roughened.
When RP sheets are laminated and heated under pressure to form an integral sheet, there is a method in which a press plate with an uneven surface is used as a press plate for applying pressure. The degree of roughening of the CFRP sheet surface is determined by the center line average roughness (JIS B
601) is 0.4-2.0, preferably 0.5-1
．． It is preferable to specify it within the range of 5-. Such a roughened CFRP sheet has a friction coefficient of 0.5 or less and a light reflectance of 10 or less, and itself has good sliding properties and low light reflectance.

Next, in the present invention, a resin paint containing a sliding agent is applied onto the rough surface of the CFRP sheet and heat-treated to form a coating film containing the sliding agent. As the sliding agent, fluororesin (for example, polytetrafluoroethylene, etc.),
Examples include graphite and molybdenum disulfide, and the average particle size thereof is 0.1 to 10 tones, preferably 0.2 to 54 tones. As the coating resin, a thermosetting resin or a thermoplastic resin is used, and thermosetting resins such as urethane-based, epoxy-based, phenol resin, and melamine resin are preferably used from the viewpoint of adhesive strength. In addition, if necessary, this paint liquid may be used to improve the light-shielding properties of the shutter blades.
Also, to improve the conductivity of the coating film.

A black conductive agent such as carbon black may also be mixed. The CFRP sheet used as a base material in the present invention is
Since it contains conductive carbon fibers, it has excellent conductivity in itself and is not easily charged by surface friction, so it is not necessary to add a conductive agent to the coating film. Depending on the thickness, it may be advantageous to add this. The thickness of the coating film is usually 0.1 to 20 μs, preferably 0.5 to 15 μs, and has an uneven surface corresponding to the uneven surface of the CFRP sheet using the surface of this coating film as a base material.

The CFRP sheet having the resin coating film containing the sliding agent thus obtained has a center line average roughness of 0.2 to 2.
．． 0, preferably 0.3 to 1.5, usually 0.5
It has the following coefficient of friction and has very good sliding properties, and also has a low light reflectance of 10% or less, making it extremely suitable as a material for high-speed shutter blades. The shutter blade of the present invention can be obtained by cutting this CFRP sheet into a desired shape.

(Effects of the Invention) The shutter blade of the present invention has a resin coating film containing a sliding agent formed on the rough surface of a roughened CFRP sheet, and has excellent sliding properties and conductivity. In addition to being easy to operate at high speed, it is also less likely to be charged. Furthermore, since the surface of the CFRP sheet base material is formed with an uneven surface and the coating film is also formed with a corresponding uneven surface, the light reflectance is extremely low.

(Example) Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Unidirectionally oriented carbon fibers were impregnated with an epoxy resin-based cured resin containing 5% by weight of carbon black with an average particle size of 0.03 to create a prepreg sheet with a carbon fiber basis weight of 27 g/m. . These 3 plies of prepreg sheets were stacked 0'/90"10' so that they were plane symmetrical, and mirror-finished stainless steel plates were placed on the top and bottom of the sheets. Using a hot press preheated to 130°C, the 3-ply prepreg sheets were stacked in a 0'/90"10' stack. cd
The resin was cured for 90 minutes. Thereafter, it was slowly cooled to room temperature to obtain a sheet of carbon fiber reinforced resin. The thickness of this molded sheet is 96. The carbon fiber-reinforced resin sheet was excellent, with little unevenness in thickness, no disorder in the orientation of carbon fibers, and no warpage.

Next, the surface of the carbon fiber reinforced resin sheet obtained above was roughened by sandblasting. As a result, the center line average roughness (Ra) of the surface was 1.3 degrees, and the surface resistance was 1.
It was less than 0x10'Ω/mouth. On the other hand, in a mixed solution of 34.1 parts by weight of water and 2.6 parts by weight of ethyl alcohol, (
a) Water-soluble melamine resin (methylolated melamine resin)
("Sumitex Resin 3", manufactured by Sumima Kagaku Kogyo Co., Ltd., solid content concentration = 80% by weight) 7.6 parts by weight and conductive carbon black (average particle size: 0.1-0.2.) are anionic. A liquid dispersed in a water-soluble acrylic resin aqueous solution containing a surfactant (carbon black concentration near 3% by weight, acrylic resin concentration: 4.2 weight 15.9 parts by weight, (b) polytetrafluoroethylene (prFE) (Average particle size: 0.3
After dispersing n) and polyurethane resin in water (polytetrafluoroethylene concentration: 218% by weight, polyurethane resin concentration: 10% by weight), 14.5 parts by weight and (c) ammonium chloride aqueous solution (ammonium chloride concentration = 20% by weight)
) 0.158 parts by weight was added and mixed uniformly to prepare a paint.

Next, this paint was applied to the surface of the carbon fiber reinforced resin sheet, which had been roughened by sandblasting, and heated to 100°C.
It was heat-treated for 10 minutes. The surface characteristics of the carbon fiber-reinforced resin sheet having the coating film thus obtained were investigated, and the results are shown in Table 1.

Comparative Example 1 A carbon fiber reinforced resin sheet having a coating film was obtained in the same manner as in Example 1 except that a carbon fiber reinforced resin sheet whose surface was not roughened was used. The surface characteristics of this material are shown in Table 1.

The method for measuring surface properties is as follows.

(1) Surface roughness (center line average roughness): JIS B 06
01(2) Surface light reflectance: JIS Z 8741(3)
Friction coefficient: ASTM D 1894 (4) Surface resistance: J
IS K 6911 Table-1 As can be seen from the results shown in Cloth-1 above, the product of the present invention has a low coefficient of friction, excellent sliding properties, low surface light reflectance, and low surface resistance. It has excellent properties as a high-speed shutter blade.

Claims (3)

[Claims] (1) A black light-shielding carbon fiber reinforced resin sheet formed on an uneven surface with a center line average roughness in the range of 0.4 to 2.0 μm is used as a base material, and a sliding agent is applied to the uneven surface. Shutter blades with excellent sliding properties are formed by forming a resin coating film containing the following. (2) The shutter blade according to claim 1, wherein the sliding agent is a fluororesin or graphite. (3) The shutter blade according to claim 1 or 2, wherein the coating film contains carbon black.