JP2000301044A - Sintered hard alloy made coating utensil for coating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the non-uniformity of bonding phase distribution, to enhance the strength, hardness, toughness, wear resistance, lubricity and to improve impact resistance and the resistance to fine clipping by uniformizing the particle size distribution of tungsten carbide and uniformly dispersing and incorporating tungsten carbide and the bonding phase. SOLUTION: At least the tip part of a coating utensil is composed of the sintered hard alloy and the sintered hard alloy contains 2-16 wt.% bonding phase consisting essentially of cobalt and the balance a hard phase consisting essentially of tungsten carbide and has the hardness of 90.0 (HRA)-93.0 (HRA) in scale A of Rockwell hardness and the coercive force satisfying the relation 50X-4320>Y<=35X-3035 when the hardness is expressed by X (HRA), the coercive force of the sintered hard alloy is expressed by Y (ersted).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plastic,
Coating device for applying a coating liquid consisting of a liquid material containing an inorganic substance and an organic substance to the surface of an object to be coated represented by a support such as paper, metal foil, metal plate, and glass. And a cemented carbide coating tool typified by a die coater, a coater die, and a coating tool called a doctor edge, from which the coating liquid is discharged. A solution containing magnetic particles such as ferrite, a solution containing particles of photographic photosensitive material such as silver halide, a solution coated on the surface of paper such as copy paper, etc. A coating made of cemented carbide for a coating apparatus, which is provided in an apparatus for applying a coating liquid represented by formula (1) to form a coating film, and which is formed in a structure such that the coating film is coated. It relates to a tool attached.

[0002]

2. Description of the Related Art Conventionally, a heat-sensitive film,
2. Description of the Related Art Various kinds of coatings represented by a conductive film, a low-reflection conductive film, an ultraviolet ray preventing film, an electromagnetic wave preventing film, a protective film, and a magnetic film have been used. Among them, for video,
Audio film, disk, sheet, tape,
2. Description of the Related Art In a magnetic recording medium represented by a drum, a coating apparatus of various types is used for coating a coating film containing magnetic particles on a surface of an object to be coated such as plastic. There is a coating tool installed in these coating devices and formed in a structure such that a coating liquid for forming a coating film flows out.

[0003] Among the coating tools, the coating liquid is applied to a continuously running object to be coated with a uniform thickness while adjusting and controlling the amount of the coating liquid flowing out mainly by a coating tip. There is a coating tool to be applied. The coating tip of this coating tool is
Shape accuracy, surface accuracy, sharp edges without blade spills are required, and at the same time wear due to hard dispersed particles consisting of inorganic substances in the coating liquid and corrosion due to various additives such as resins and solvents are remarkable. , Corrosion resistance against chemical corrosion (corrosion) and electrical corrosion (erosion),
Improvement in lubricity is desired.

[0004] In recent years, the use of cemented carbide at the coating tip or proposals related thereto have been made. However, even when the conventional cemented carbide was used for the coating tip, the transition to high-speed coating and the transition of various additives such as resins and solvents and hard dispersed particles from the beginning of development were made. In addition, with the transition of the coating configuration in which the coating is coated on the laminate, the configuration with multiple slits or the configuration in which multiple application tools are used in one process has been adopted. There is a problem in that the abrasion and corrosion resistance are not satisfactory, and the life is short.
Representative examples proposed to improve this problem include Japanese Patent Application Laid-Open Nos. 57-84771 and 2-26.
No. 5,673, Japanese Unexamined Patent Application Publication No. 2-265679, and Japanese Unexamined Patent Application Publication No. 6-114316.

[0005]

Among the prior arts in which a cemented carbide is applied to a coating tool, Japanese Unexamined Patent Publication No. 57-84771 discloses a cemented carbide having a hardness of 88 or more on a Rockwell A scale. There is disclosed a coating apparatus provided with a coating tool comprising a doctor edge (a portion corresponding to a coating tip). Also, Japanese Patent Application Laid-Open No. Hei 2-265677 discloses Co.
Content is 15% by weight or less and hardness is 83HRA-89H
A coating apparatus provided with a coating tool using a cemented carbide as RA as a doctor edge is disclosed. When the cemented carbide disclosed in these two publications is used for the coating tip, abrasion resistance and corrosion resistance are improved as compared with the conventional steel coating tip, but the coating speed and the coating solution are improved. In particular, when the coating liquid contains high-hard materials such as magnetic powder, hard ceramic powder, and diamond-like carbon in the coating liquid, the coating liquid flows out from the coating tip. , Abrasion wear caused by high-hardness substances in the coating solution and corrosion wear caused by fatty acids and sulfur-containing organic substances cause slight damage to the tip of the coating, resulting in the smoothness of the coating surface coated on the object to be coated. Is reduced, which makes it impractical.

[0006] Japanese Patent Application Laid-Open No. 2-265673, which is cited as a prior art of the present invention, discloses that W having an average particle size of 1.5 μm or less is used.
There is disclosed a coating apparatus having a doctor edge made of a cemented carbide made of C and Co, or a cemented carbide to which carbides of Ti, Ta, and Nb having an average particle size of 5 μm or less are added as necessary. I have. The cemented carbide disclosed in this publication is good in surface accuracy, sharpness, etc., but does not satisfy corrosion resistance and has slipperiness with an object to be coated or a coating liquid as described above ( Lubricity), resulting in a short life. Further, JP-A-6-114316 discloses that C
A coating apparatus provided with a doctor edge of a cemented carbide made of a binder phase containing 0.5 to 1.0% Cr in o is disclosed. The corrosion resistant cemented carbide disclosed in the publication is Co
Although the corrosion resistance is improved by the binder phase to which Cr is added, there is a problem that the life is short due to the synergistic effect of corrosion and friction wear and abrasion wear, and a stable life cannot be obtained.

The present invention has solved the above-mentioned problems. More specifically, the present invention makes uniform the particle size distribution of tungsten carbide and uniformly disperses and mixes tungsten carbide and a binder phase. It eliminates uneven distribution of the binder phase, improves strength, hardness, toughness, abrasion resistance, lubricity, and improves impact resistance and micro-breakage resistance. Further, if necessary, Ni, Cr, V, Cr ₃ C ₂ , V
By forming at least one of C in solid solution, the corrosion resistance, abrasion resistance and lubricity against chemical and electrical corrosion due to the coating liquid are greatly improved, and formed on the object to be coated. It is an object of the present invention to provide a cemented carbide coating tool for a coating apparatus which increases the surface roughness of a coating film to be formed, suppresses streak-like defects generated on the coating surface as much as possible, and achieves a long service life. .

[0008]

Means for Solving the Problems The inventors of the present invention have studied the extension of the life of a cemented carbide coating tool provided in a coating apparatus. Uniform particle size distribution of the hard phase in the cemented carbide that forms the binder phase, especially adjusting the particle size of tungsten carbide to enhance micro-breakage resistance, and making the particle size distribution uniform, and bonding with the hard phase When the phase is uniformly dispersed and uniformly mixed, the uneven distribution of the hard phase and the binder phase is eliminated,
The corrosion resistance to the resin and organic solution in the coating liquid is improved, and the particle size distribution of the hard phase, especially the particle size and particle size distribution of tungsten carbide, are almost affected by the coercive force of the cemented carbide. Tungsten particle size distribution and particle size are converted as the relationship between coercive force and hardness of cemented carbide considering the amount of binder phase, etc., keep the value of coercive force and hardness of cemented carbide constant It has been found that the strength, hardness, toughness, abrasion resistance, and lubricity can be improved, and that the object is achieved, and the present invention has been completed.

That is, a cemented carbide coating tool for a coating apparatus according to the present invention is provided in a coating apparatus and designed so that a coating film is coated on a surface of an object to be coated. A tool having a coating tip for applying the coating film, wherein at least the coating tip of the coating tool is made of a cemented carbide; The hard alloy is composed of 2 to 16% by weight of a binder phase containing cobalt as a main component and a hard phase containing tungsten carbide as a main component and inevitable impurities,
The cemented carbide has a hardness of 90.0 (HRA) or more and 93.0 (HRA) or less on an A scale of Rockwell hardness, and the hardness is represented by X (unit: HRA). Is expressed as Y (unit: Oersted),
The coercive force (Y) is 50X-4320> Y ≧ 35X-30
35 is within the range satisfying the expression (35).

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A coating apparatus on which a coating tool of the present invention is installed is attached to a coating apparatus for coating a glass surface such as a CRT panel, an audio apparatus, a video apparatus, a computer apparatus, and the like. Coating equipment for producing magnetic recording media in which a magnetic film is coated on the surface of films, disks, sheets, tapes, drums, etc. used for magnetic recording, or the surface of fax paper, copy paper, photographic film, etc. Coating device for coating, etc.
The apparatus is not particularly limited as long as the apparatus is applied with a coating liquid containing an inorganic substance and an organic substance.

[0011] The coating tool of the present invention provided in the coating device has at least a coating tip, and the coating tip is formed in a state in which the coating liquid flows out. In particular, at least one hole-shaped outlet is formed on the end face on the side where the coating liquid flows out, so that the coating liquid can be sprayed out, or A typical example is a case in which a slit-shaped outlet is formed on the same end surface to allow the coating liquid to flow out linearly to planarly. If the coating tip has a slit-shaped coating liquid outlet formed on the end face on the side where the coating liquid flows out, the coating liquid flowing out of the slit-shaped coating liquid outlet is formed. Is preferable because it facilitates adjustment of the film thickness and film area on the surface of the film-shaped coated object that moves at a constant speed, and facilitates production of a tape-shaped coated object such as a magnetic recording medium. is there. In the case of a coating tool provided in a coating apparatus for producing a magnetic recording medium, the slit-shaped coating liquid outlet needs to be adjusted according to the target film thickness, and in particular, 10 μm ~ 1m
It is preferable that the slit width is m.

This cemented carbide is substantially composed of a binder phase and a hard phase. Among these, the binder phase is specifically, for example, a metal of Co, Ni, Co—Ni, Co—C
r, Co-Cr-C, Co-V, Co-VC, Co-
Cr-V, Co-W, Ni-Cr, Ni-Cr-V, N
i-W, Co-Ni-Cr, Co-Ni-W, Co-W
-M, Ni-WM or Co-Ni-WM (however,
M represents two or more elements of Cr, Mo, and V).

Of these binder phases, 7
In the case of a binder phase in which 5% by weight or more of Co and at least 25% by weight of one or more solid solution elements of chromium, molybdenum, vanadium, tungsten, chromium carbide, and vanadium carbide form a solid phase, It is preferable because the diameter and the particle size distribution can be easily adjusted. Particularly, when it is composed of one or more solid-solution binder phases of chromium, vanadium, chromium carbide, and vanadium carbide, the effect of suppressing the particle growth of the hard phase in the alloy is improved. Is preferred because of high corrosion resistance and particularly excellent corrosion resistance and wear resistance as alloy characteristics. If the amount of the binder phase is less than 2% by weight with respect to the entire alloy, the strength and toughness are reduced, so that the grinding becomes difficult. Conversely, when the content exceeds 16% by weight, wear resistance deterioration due to a decrease in hardness becomes remarkable, so that the content is set to 2 to 16% by weight. This binder phase is contained in an amount of 3 to 12% by weight based on the entire cemented carbide in view of abrasion wear resistance, corrosion wear resistance, friction wear resistance, micro edge damage resistance and micro chipping resistance. Is preferable.

In addition to the binder phase, the hard phase constituting the cemented carbide as the coating tool of the present invention is substantially composed of only tungsten carbide, or is composed of tungsten carbide as a main component and other periodic phases. There may be mentioned a case of a hard phase comprising at least one cubic structure compound among carbides, nitrides, carbonates, nitrides of the metals belonging to groups 4a, 5a and 6a of the table and their mutual solid solutions. it can. Among them, a hard phase consisting essentially of tungsten carbide is preferred because of its excellent toughness and strength. Tungsten carbide is 98% by weight or more based on the hard phase, and 4a, 5a, In the case of a hard phase composed of at least one cubic structure compound among carbides, nitrides, carbonates, nitrides of group 6a metals and their mutual solid solutions, it is easy to adjust the particle size of tungsten carbide. , And tend to increase hardness and wear resistance.

Among these hard phases, the hard phase of the cubic structure compound is a compound crystallographically having a cubic structure, and specifically, for example, TiC, ZrC, HfC, Ta
C, NbC, VC, (W, Ti) C, (W, Ti, T
a) C, (W, Ti, Ta, Nb) C, Ti (C,
N), Zr (C, N), (W, Ti) (C, N),
(W, Ti, Ta) (C, O), (W, Ti, Ta)
At least one of (N, O) and (W, Ti, Ta) (C, N, O) can be mentioned as a representative example. This cubic structure compound tends to decrease the strength of the cemented carbide, and preferably has an average particle size of 1 μm or less to suppress the strength, and has a particle size as uniform as possible.
It is preferable that the particles are uniformly dispersed because they have excellent strength and toughness.

Tungsten carbide present as a main component of the hard phase has an average particle size of 1.5 μm or less, preferably 1.0 μm or less, and 90% or more has an average particle size of ± 0.5 μm. If it is in the range, especially the average particle size + 1μ
When the particle diameter of m is 5% or less based on the whole tungsten carbide, it is preferable because it has the effect of improving the surface accuracy and the sharpness of the coated tip.

The coating tool of the present invention comprising a cemented carbide having the above composition has a hardness as an alloy property of 90.0 HRA on an A scale of Rockwell hardness.
If less, the wear resistance is significantly reduced, and conversely 93.0H
If the RA is higher than RA, minute damage and minute deficiency are likely to occur in the edge portion, and the manufacturing method becomes difficult. Therefore, the value is set to 90.0 to 93.0 HRA. When this hardness is represented by X (unit: HRA) and the coercive force of the coating tool of the present invention is represented by Y (unit: Oersted), if Y <35X-3035, then abrasion-resistant wear is obtained. The resistance, corrosion wear resistance and friction wear resistance are remarkably reduced, and the balance of all properties including edge micro damage resistance, micro chipping resistance and plastic deformation damage resistance is poor, and stable life Is difficult to obtain.

The coating tool of the present invention is not particularly limited in terms of shape, and may be made of a cemented carbide having the above-described composition, and is a typical example of a coating tip for a die coater. , FIG. 1, FIG. 2 and FIG. 1 is a schematic perspective view exemplifying a coating tool of the present invention, and FIG. 2 is a schematic vertical sectional view taken in a direction parallel to a slot width of a coating tip portion in FIG. FIG.
FIG. 3 is a schematic longitudinal sectional view shown as a modification of FIG. 2.
1, 2 and 3, reference numeral 1 denotes a coating tip, reference numeral 2 denotes a slot portion (discharge port) through which the coating liquid is extruded, and reference numeral 3 denotes a coating liquid. It is a pocket to store. Further, in these FIGS. 1 to 3, the outlet portion is made of cemented carbide, and the other base portions are made of steel,
It is also preferable from the viewpoint of cost to adopt a structure in which both are joined.

The application tool of the present invention can be manufactured by applying a conventional powder metallurgy method using commercially available starting material powders as described in detail in the following test. The important point in the production method is, specifically, first, using a tungsten carbide powder having as fine and uniform particle size distribution as a starting material, the other starting material powder has the same tendency, and has a small number of unavoidable impurities. Select starting material powder. Next, the important points in the manufacturing process are to set the low carbon region in the composition, to strengthen the mixing and pulverization in the mixing process and to avoid mixing of impurities during mixing, and in the sintering process to The temperature can be as low as possible.

[0020]

According to the coating tool of the present invention, the particle size of tungsten carbide in the alloy is determined by the relationship between the content of the binder phase constituting the cemented carbide and the hardness and coercive force which are the characteristics of the alloy. Determined, and the particle size distribution is maintained uniformly. As a result, it has the effect of increasing the abrasion resistance, the resistance to micro-damage, and the resistance to micro-breakage. Further, the surface accuracy of the alloy is easily increased, and the alloy has an indirect action of improving the sharpness and lubricity of the alloy. In addition, the coating tool of the present invention has the above-described functions if at least one of chromium, chromium carbide, vanadium, and vanadium carbide is dissolved in the binder phase constituting the cemented carbide. In addition, the effect of suppressing the grain growth of the hard phase, increasing the fineness of the hard phase and increasing the uniformity of the particle size distribution, and the effect of significantly increasing the corrosion resistance are added, and a large amount of W is dissolved in the binder phase. Has the effect of improving strength, toughness, and corrosion resistance, and has the effect of increasing lubrication, abrasion resistance, surface accuracy, cutting edge, and corrosion resistance to chemical and electrical corrosion. Is what it is.

[0021]

First, a tungsten carbide powder having an average particle size of 1.5 μm (hereinafter referred to as “f-WC”) and a tungsten carbide powder having an average particle size of 3.0 μm (hereinafter, referred to as “f-WC”) were used as starting material powders. m-WC ”) and the average particle size is 1.2
Co, Cr ₃ C ₂ , VC, Ta in the range of μ1.8 μm
Using the powders of C, TiC, NbC, and Ni, weigh the blending components for the products 1 to 7 of the present invention shown in Table 1 and charge them into a stainless steel pot together with an acetone solvent and a cemented carbide ball. After mixing and grinding for 72 hours, the mixture was dried to obtain a mixed powder. A mold is filled with these mixed powders and 2 ton / c
With a pressure of m ^2, a compact was prepared from a cemented carbide having a diameter of about 10 mm × a height of 30 mm and a cemented carbide of about 13 mm × 13 mm × 5 mm, and this compact was formed from alumina and carbon fiber. The sheet was heated and held for 1 hour at a temperature shown in Table 1 in a vacuum at an atmospheric pressure of 10 Pa to obtain cemented carbides of the present invention products 1 to 7.

In addition to the starting material powders used in the products 1 to 7 of the present invention, WC having an average particle size of 4.5 μm (hereinafter referred to as “L-WC”)
), F-WC, m-WC and L-WC are 1: 1:
Starting material powder with WC (hereinafter, referred to as “mx-WC”) mixed in No. 3 was added to obtain the composition components for Comparative Products 1 to 4 shown in Table 1. Among the other manufacturing steps, the same as the products 1 to 7 of the present invention except that the mixing and pulverizing time was set to 24 hours, the sintering temperature was set to the conditions described in Table 1,
Was obtained.

The thus-obtained cemented carbide samples of the present invention products 1 to 7 and comparative products 1 to 4 were wet-ground with a # 230 diamond grindstone to obtain a shape of about 10 mm diameter × 30 mm height and about 13 mm × 13 mm. It was manufactured into a cemented carbide having a shape of 5 mm. Of these samples, 13 mm x 13 mm x 5
The hardness (HRA) using a Rockwell hardness tester and the coercive force (unit: Oersted) using a coercivity meter made in Germany were determined for each sample of the mm-shaped cemented carbide, and the results are shown in Table 2.

Further, one end face of 13 mm × 5 mm of the sample having the same shape was lapped, the structure was observed with a metallographic microscope and a scanning electron microscope, and the average particle size of tungsten carbide of each sample was also shown in Table 2. In addition, among these samples, the present invention products 1 to 7 have a uniform tungsten carbide particle size,
While the dispersion of the binder phase was good, the comparative products 1-4
In Example 1, the tungsten carbide had a non-uniform particle size, poor dispersion of the binder phase, and a pool of the binder phase was observed. Further, each sample of the same shape is used as a magnetic film constituting the surface film of the recording medium in a solution containing dibenzyl dibenzo, benzothiazole, higher fatty acid, a binder resin, etc. which have been conventionally used at room temperature. After immersion for 30 days, the state of corrosion was observed with an optical microscope, and the results of the corrosion test are shown in Table 3. The corrosion test results at this time are indicated by the following symbols. ｛Notation sign and corrosion status are as follows: ：: no corrosion, ○: slight corrosion (slightly cloudy), △: corrosion (cloudy), ×: significant corrosion (color change)｝

Next, the outer periphery and one end surface of a cemented carbide sample having a shape of 10 mm in diameter × 30 mm in height are wrapped, and these are used as pins, and a disk in which a polyethylene phthalate thick film is coated on a steel plate is used. Then, a simple test corresponding to the preparation of a coating film on a recording medium was performed using a pin-disk friction and wear tester. The simple test conditions are as follows: a clearance of 1 mm is provided between the pin and the disc, and during this clearance, molybdenum powder, alumina powder, ferrite powder, dibenzyl dibenzyl, benzothiazole, higher fatty acid and binder resin are constantly used. Rotate the pin on the disk in the presence of a solution containing
After a lapse of time, the end face corrosion and the friction and wear state of the pin were observed, and the results are also shown in Table 3. The pin-disk test results at this time are indicated by the following symbols. ｛Notation symbols and damage status are as follows: ◎: No damage at all, ○: Slight damage,
△: Damaged, ×: Significant damage △

On the basis of the above simple test results, for the products 2, 3, and 4 of the present invention and the comparative products 2 and 3, using mixed powders having the same composition as those of each of the products, press forming, preforming, sintering, and grinding. Through the process, a coating tool including a coating tip for a coating device shown as a schematic diagram in FIG. 1 was produced. These coating tools are mounted on a magnetic tape coating apparatus that has been conventionally used, a coating test including a magnetic film of a magnetic recording medium is performed, and the coating tool is coated on a magnetic tape as an object to be coated. The life evaluation determined from the occurrence of streaks in the coated film and the state of minute damage to the edge at the coating tip of the coating tool is as follows.
Was about 1.3 times, the invention product 5 was about 2.1 times, the invention product 4 was about 2.5 times, and the invention product 3 was about 3.0 times.

[0027]

[Table 1]

[0028]

[Table 2]

[0029]

[Table 3]

[0030]

According to the present invention, the coating tool of the present invention is more resistant to corrosion by fatty acids, extreme pressure additives, rust inhibitors and the like contained in the coating liquid than conventional coating tools made of cemented carbide. Excellent abrasion resistance due to chemical and electrical corrosion, especially excellent abrasion resistance due to magnetic powder, hard ceramic powder, etc. contained in the coating solution. It has excellent micro-damage resistance at the edge of the coating at the coating tip at the outlet of the liquid, and the properties of the combined alloy are excellent in a well-balanced manner. Since the surface roughness can be suppressed and the generation of streaks on the surface of the object to be coated can be suppressed, it has an excellent effect of long life.

[Brief description of the drawings]

FIG. 1 is a perspective view schematically illustrating a coating tool when a practical test is attempted in a practical test.

FIG. 2 is a longitudinal sectional view from a direction parallel to a slit width in FIG.

FIG. 3 is a longitudinal sectional view shown as a modification of FIG. 2;

[Explanation of symbols]

 Reference numeral 1 is a coating tip. Reference numeral 2 denotes a slot (discharge port) through which the coating liquid is extruded. Reference numeral 3 denotes a pocket for storing a coating liquid.

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[Procedure amendment]

[Submission date] October 7, 1999 (1999.10.
7)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0007

[Correction method] Change

[Correction contents]

The present invention has solved the above-mentioned problems. More specifically, the present invention makes uniform the particle size distribution of tungsten carbide and uniformly disperses and mixes tungsten carbide and a binder phase. It eliminates uneven distribution of the binder phase, improves strength, hardness, toughness, abrasion resistance, lubricity, and improves impact resistance and micro-breakage resistance. Further, if necessary, Ni, Cr, V, Cr ₃ C ₂ , V
By forming at least one of C in solid solution, the corrosion resistance, abrasion resistance and lubricity against chemical and electrical corrosion due to the coating liquid are greatly improved, and formed on the object to be coated. It is an object of the present invention to provide a cemented carbide coating tool for a coating apparatus, which has improved surface accuracy of a coating film surface, suppresses streak-like defects generated on the coating surface as much as possible, and achieves a long service life.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0013

[Correction method] Change

[Correction contents]

Of these binder phases, 7
In the case of a binder phase in which 5% by weight or more of Co and at least 25% by weight of one or more solid solution elements of chromium, molybdenum, vanadium, tungsten, chromium carbide, and vanadium carbide form a solid phase, It is preferable because the diameter and the particle size distribution can be easily adjusted. Particularly, when it is composed of one or more solid-solution binder phases of chromium, vanadium, chromium carbide, and vanadium carbide, the effect of suppressing the particle growth of the hard phase in the alloy is improved. Is preferred because of high corrosion resistance and particularly excellent corrosion resistance and wear resistance as alloy characteristics. If the amount of the binder phase is less than 2% by weight with respect to the entire alloy, the strength and toughness are reduced, so that the grinding becomes difficult. Conversely, if the content exceeds 16% by weight, the wear resistance is significantly deteriorated due to a decrease in hardness. Therefore, the content is set to 2 to 16% by weight. This binder phase is contained in an amount of 3 to 12% by weight based on the entire cemented carbide in view of abrasion wear resistance, corrosion wear resistance, friction wear resistance, micro edge damage resistance and micro chipping resistance. Is preferable.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction contents]

Further, one end face of 13 mm × 5 mm of the sample having the same shape was lapped, the structure was observed with a metallographic microscope and a scanning electron microscope, and the average particle size of tungsten carbide of each sample was also shown in Table 2. In addition, among these samples, the present invention products 1 to 7 have a uniform tungsten carbide particle size,
While the dispersion of the binder phase was good, the comparative products 1-4
In Example 1, the tungsten carbide had a non-uniform particle size, poor dispersion of the binder phase, and a pool of the binder phase was observed. Further, each sample of the same shape is used as a magnetic film constituting a surface film of a recording medium in a solution containing dibenzyl disulfide, benzothiazole, higher fatty acid, a binder resin, and the like which have been conventionally used at room temperature. After immersion for 30 days, the state of corrosion was observed with an optical microscope, and the results of the corrosion test are shown in Table 3. The corrosion test results at this time are indicated by the following symbols. ｛Notation sign and corrosion status are as follows: ：: no corrosion, ○: slight corrosion (slightly cloudy), △: corrosion (cloudy), ×: significant corrosion (color change)｝

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0025

[Correction method] Change

[Correction contents]

Next, the outer periphery and one end surface of a cemented carbide sample having a shape of 10 mm in diameter × 30 mm in height are wrapped, and these are used as pins, and a disk in which a polyethylene phthalate thick film is coated on a steel plate is used. Then, a simple test corresponding to the preparation of a coating film on a recording medium was performed using a pin-disk friction and wear tester. The simple test conditions are as follows: a clearance of 1 mm is provided between the pin and the disc, and during this clearance, molybdenum disulfide powder, alumina powder, ferrite powder, dibenzyl disulfide, benzothiazole, higher fatty acid and binder resin Rotate the pin on the disk in the presence of a solution containing
After a lapse of time, the end face corrosion and the friction and wear state of the pin were observed, and the results are also shown in Table 3. The pin-disk test results at this time are indicated by the following symbols. ｛Notation symbols and damage status are as follows: ◎: No damage at all, ○: Slight damage,
△: Damaged, ×: Significant damage △

Claims (8)

[Claims] 1. A coating tool provided in a coating device and designed so that a coating film is coated on a surface of an object to be coated, wherein the coating tool removes the coating film. The coating tool is provided with a coating tip, and at least the coating tip of the coating tool is made of a cemented carbide, and the cemented carbide contains a cobalt-based binder phase of 2 to 16%. Wt.% And the balance of a hard phase containing tungsten carbide as a main component. The cemented carbide has a hardness of 90.000 A on a Rockwell hardness scale.
0 (HRA) or more and 93.0 (HRA) or less,
When the hardness is represented by X (unit: HRA) and the coercive force of the cemented carbide is represented by Y (unit: Oersted), the coercive force satisfies the range of 50X-4320> Y ≧ 35X-3035. Cemented carbide coating tool for coating equipment. 2. A cemented carbide coating tool for a coating apparatus according to claim 1, wherein said coating tip has a slit-shaped outlet at which a coating liquid flows out. 3. The binder phase contains at least 75% by weight of cobalt in the binder phase, and the balance contains one or more binder phase strengthening substances of tungsten, chromium, vanadium, chromium carbide, and vanadium carbide. The coating tool made of a cemented carbide for a coating device according to claim 1 or 2, which is applied. 4. The coating tool according to claim 1, wherein the hard phase is substantially made of tungsten carbide. 5. The hard phase contains tungsten carbide in an amount of 98% by weight or more of the hard phase, and the balance is 4a or 4a in the periodic table.
4. The composition according to claim 1, comprising at least one cubic structure compound selected from carbides, carbonitrides, carbonates, and mutual solid solutions of metals belonging to the group 5a and 6a. 5. Cemented carbide coating tool for coating equipment. 6. The compound having a cubic structure having an average particle size of 1 μm.
The cemented carbide coating tool for a coating device according to claim 5, which is not more than m. 7. The tungsten carbide has an average particle size of 1.
5 μm or less, and 90% or more has an average particle size of ± 0.5.
The cemented carbide coating tool for a coating apparatus according to any one of claims 1 to 6, comprising a uniform particle diameter in a range of μm. 8. A coating tool made of a cemented carbide for a coating apparatus according to claim 1, wherein said coating tool is used for producing a film on a magnetic recording medium.