JPS62202073A - Sliding member - Google Patents

Abstract

PURPOSE:To improve the wear resistance and surface lubricity of a sliding member by forming an i-carbon film on the sliding surface of the sliding member so as to provide surface lubricity. CONSTITUTION:A hard i-carbon film is formed on at least the sliding surface of the body of a sliding member by a process including a stage for producing ions contg. carbon, e.g., ionization and vapor deposition using hydrocarbon as starting material. The resulting sliding member is used as a heat sensitive head or the like and has improved wear resistance and surface lubricity.

Description

[Detailed Description of the Invention] CObject of the Invention] (Industrial Application Field) The present invention relates to a sliding member, and particularly to improving wear resistance and surface lubricity.

(Prior art) Conventionally, in order to improve the wear resistance of sliding members, hard materials such as titanium nitride or aluminum oxide have been applied to the sliding surface of the sliding member body by sputtering, chemical vapor deposition, or ion beam deposition. Coating is performed using a method such as a rating method. However, since these hard materials have poor surface lubricity, they have drawbacks such as adhesion and peeling during use.

On the other hand, in order to impart surface lubricity to sliding members, the sliding surface of the sliding member body is coated with a solid lubricating film such as molybdenum sulfide or tungsten sulfide using a method similar to the above. . However, since these solid lubricating films have low wear resistance, they wear out during use, causing problems such as decreased accuracy and decreased lifespan.

Further, the same problem as above has occurred not only in general sliding members but also in thermal heads, for example. Thermal heads currently in use are broadly classified into thick-film types and thin-film types, but since they can be considered structurally the same, the thick-film type will be explained below as an example. The conventional thick film type thermal head, as shown in Fig. 4,
For example, a pen-shaped insulating base material 1 made of aluminum oxide
An electrode 1 made of, for example, Pd-Ag, gold, etc.
2 has a structure in which a thick film resistor 13 made of, for example, ruthenium oxide is formed at the tip part by screen printing, and the outer periphery of the electrode 12 and the thick film resistor 3 is covered with, for example, high melting point crystallized glass 14. are doing. Note that the portion of the high melting point crystallized glass 14 provided on the outer periphery of the electrode 12 is an electrode protective layer for the purpose of insulating and protecting the electrode.
A portion provided on the outer periphery of the thick film resistor 13 is a wear-resistant layer intended to provide wear resistance. In this way, the electrode protective layer and the wear-resistant layer are usually formed of the same material, and there is no boundary between them.

The main characteristics required of the wear-resistant layer at the tip of the thick-film thermal head described above are: ■ electrical insulation, ■ high wear resistance, and ■ high adhesion to the thick-film resistor 13. ■It has high surface lubricity. The reason why these characteristics are required will be explained in detail below.

The electrical insulation property (2) is a property required from a safety standpoint, that is, to prevent an electric shock accident when the thick film resistor 13 is heated by electricity. The abrasion resistance (2) is a particularly required property, since it is desirable from the viewpoint of recording clarity that there should be as little abrasion as possible even during long-term sliding contact with heat-sensitive recording paper. Furthermore, when the wear-resistant layer is worn away and the thick-film resistor 13 is exposed, the thick-film resistor 13 generally has low wear resistance, so it wears out quickly, and the electrical resistance value and shape change, causing the thermal head It will no longer be able to perform its normal functions. The adhesion to the thick film resistor 13 described in (2) is a required characteristic because if the wear-resistant layer peels off from the thick film resistor 13 during use, it will cause the above-mentioned trouble. The lubricity described in (2) is a property required for smooth feeding of recording paper.

However, although high melting point crystallized glass 14, which has been conventionally used as a material for the wear-resistant layer, has good electrical insulation properties, it does not have sufficient wear resistance and surface lubricity, so it cannot be used for long periods of time or at high speeds. There was a risk that normal recording would not be possible.

Therefore, small lumps of wear-resistant ceramics such as diamonds and rubies are bonded as materials for the coating layer of sliding members and the wear-resistant layer of thermal heads.
These do not have sufficient adhesion and often have poor surface lubricity.

Further, for example, Japanese Patent Application Laid-Open No. 59-143656 discloses a thermal head in which a diamond thin film is formed as a wear-resistant layer, but although the diamond thin film has excellent wear resistance, it does not have sufficient surface lubricity.

Furthermore, for example, JP-A-60-71597 discloses a sliding member in which a hard carbon film made of a mixed crystal of diamond and graphite is formed on the sliding surface, but this hard carbon film also has wear resistance. Although it has excellent surface lubricity, it does not have sufficient surface lubricity.

Furthermore, since the electrical insulation property is not sufficient, it cannot be used as a wear-resistant layer of a thermal head, for example.

(Problems to be Solved by the Invention) The present invention has been made to solve the above-mentioned problems, and particularly aims to provide a sliding member that is excellent in both wear resistance and surface lubricity. It is something.

[Structure of the Invention] (Means and Effects for Solving the Problems) The sliding member of the present invention is characterized in that an i-carbon film is formed on at least the sliding surface of the sliding member main body. .

In the present invention, i-carbon is hard carbon obtained by a method including a process of generating carbon-containing ions. Specifically, it can be obtained by (a) ion beam evaporation using graphite as a raw material, (b) ionization vapor deposition using hydrocarbon as a raw material, (c) ion blating method using graphite as a raw material, and the like. This i-carbon has a Vickers hardness of 3000 to [)OOOHV, and has an amorphous structure or an amorphous structure with a slightly mixed crystalline structure. Moreover, the bonding mode between carbon and carbon is s p 3
Mainly bonds, but some sp 2 bonds and sp
It may contain one bond. Furthermore, it may contain a certain amount of hydrogen as an impurity. Such i-carbon is usually transparent and has excellent electrical insulation properties.

The sliding member in which the i-carbon film is formed on the sliding surface of the sliding member main body in this manner has excellent wear resistance and surface lubricity. It also has excellent adhesion and electrical insulation properties, and is suitable, for example, as an abrasion-resistant layer of a thermal head.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

Example 1 An example in which the present invention is applied to a general sliding member will be described.

As shown in FIG. 1, an i-carbon film 2 with a thickness of 5p is deposited on the sliding surface of a sliding member body 1 made of SUS 304 stainless steel by ion beam evaporation using graphite as a raw material.
was formed.

The above sliding member (Example 1), the sliding member made only of stainless steel without any coating layer (reference example), and the sliding member in which an aluminum oxide film with a thickness of 5p was formed instead of the i-carbon film 2. A sliding member (Comparative Example 1), a sliding member in which a molybdenum sulfide film with a thickness of 5p was formed in place of the i-carbon film 2 (Comparative Example 2), and a mixed crystal of diamond and graphite in place of the i-carbon film 2 Film thickness 5 consisting of
A sliding test was conducted using a sliding member (comparative example 3) on which a hard carbon film of P was formed, and wear resistance (evaluated by thinning of the sliding surface) and surface lubricity (evaluated by coefficient of friction) were investigated. Ta. The sliding test was conducted in the atmosphere by reciprocating the sliding surface while pressing the indenter against the sliding surface at a predetermined pressure. The results are shown in Table 1.

As is clear from Table 1, the sliding member of Example 1 has excellent wear resistance, a small coefficient of friction, and excellent surface lubricity.

Example 2 An example in which the present invention is applied to a thermal head will be described. Second
As shown in the figure, a pen-shaped insulating base material 11 made of aluminum oxide is prepared, and an electrode 12 made of Pd-Ag is formed on the circumferential surface of the insulating base material 11 by screen printing, and a thick film resistor made of ruthenium oxide is attached to the tip of the pen-shaped insulating base material 11 made of aluminum oxide. 13 were respectively formed, and high melting point crystallized glass 14 was further formed around the outer periphery of the electrode 12.

Next, the outer periphery of the thick film resistor 13 was coated with an i-carbon film 15 having a thickness of about 5p by an ion blating method.

In other words, graphite is heated and heated by irradiating it with an electron beam.
After being evaporated to form carbon particles, the carbon particles were ionized and accelerated by voltage and bombarded against a thick film resistor 13 to form a 1-carbon film 15.

The above thermal head (Example 2), the thermal head shown in FIG. 4 in which glass was formed in place of the i-carbon film 15 (comparative example 4), and a diamond thin film was formed in place of the i-carbon film 15. Regarding the thermal head (Comparative Example 5), surface lubricity to thermal recording paper (evaluated by coefficient of friction)
, indentation method (Thin 5 solid FilIIl
The adhesion and abrasion resistance (evaluated by thinning of the sliding surface) were investigated according to S, Vol. 79 (1981), p. 91).

The results are shown in Table 2.

As is clear from Table 2, the thermal head of Example 2 has good properties in terms of surface lubricity (coefficient of friction against thermal recording paper), adhesion, and abrasion resistance. Furthermore, the thermal head of Example 2 showed excellent performance in the mounting test.

In the thermal head shown in FIG. 2, the high melting point crystallized glass 14 was formed around the outer periphery of the electrode 12, and the i-carbon film 15 was formed only around the outer periphery of the thick film resistor 13. As in the conventional thermal head, a high melting point crystallized glass 14 is formed around the electrode 12 and the thick film resistor 13, and a wear-resistant layer part of the high melting point crystallized glass 14 and a part of the electrode protective layer ( Alternatively, the i-carbon film 15 may be formed on the outer periphery of the entire structure.

Table 1 Table 2 [Effects of the Invention] As detailed above, according to the present invention, a sliding member particularly excellent in wear resistance and surface lubricity can be provided.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a sliding member in Embodiment 1 of the present invention;
2 is a cross-sectional view of a thermal head according to a second embodiment of the present invention, FIG. 3 is a cross-sectional view of a thermal head according to another embodiment of the present invention, and FIG. 4 is a cross-sectional view of a conventional thermal head. DESCRIPTION OF SYMBOLS 1...Sliding member main body, 2...i-carbon film, 11
... Insulating base material, 12 ... Electrode, 13 ... Thick film resistor, 14 ... High melting point crystallized glass, 15.16.
. i-carbon film.

Claims (2)

[Claims] (1) A sliding member characterized in that an i-carbon film is formed on at least the sliding surface of the sliding member main body. (2) a rod-shaped insulating base material, an electrode formed on the circumferential surface of the base material, a resistor formed at the tip of the base material and connected to the electrode, and at least the outer periphery of the electrode covered The sliding member according to claim 1, characterized in that the sliding member has an insulating electrode protector and is used as a thermal head by forming an i-carbon film on at least the contact portion with thermal recording paper. .