JP2001287845A - Surface coating layer forming method for sheet feed roller and sheet feed roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve friction characteristics and durability by enlarging hard particles in a surface coating layer of a sheet feed roller and increasing a film thickness of a surface coating layer. SOLUTION: A surface coating layer 12 including hard particles 11 of particle diameters 60-150 μm and having a film thickness 40-75 μm is formed on a surface of a sheet feed roller 9 by electrostatic powder painting to increase a friction coefficient and to make the hard particles 11 hard to be separated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a surface coat layer of a paper feed roller of an OA apparatus, a printing machine, and the like, and a paper feed roller. .

[0002]

2. Description of the Related Art In order to improve the paper feed performance of paper feed rollers of office automation equipment such as printers, facsimile machines, copiers and printing machines, the surface of recent paper feed rollers is made of synthetic resin containing hard particles such as ceramics. The coat layer is formed by spray coating, and the hard particles increase the coefficient of friction to enhance the paper feeding performance. In a conventional paper feed roller, the average particle size of the hard particles is about 20 to 50 μm, and the thickness of the synthetic resin coating layer is about 20 to 40 μm. Conventionally, as a method of forming the synthetic resin coat layer, a liquid paint obtained by mixing a ceramic powder having a particle size of 30 to 40 μm into a paint such as an epoxy resin is used. To form a synthetic resin coat layer.

Here, Japanese Patent Application Laid-Open No. 9-249326 proposes a paper feed roll in which a plating layer containing abrasive grains having a particle size of 10 to 80 μm is formed on the surface of a metal core roll. JP-A-249327 proposes a paper feed roll in which a resin coat layer containing particles having a particle size of 10 to 80 μm is formed on the surface of a metal core roll.

[0004]

[Problems to be solved by the invention] As in the prior art,
When the surface coat layer is formed by spray coating, since the thickness of the synthetic resin coat layer is about 20 to 40 μm and the average particle size of the hard particles is 20 to 50 μm, the hard particles are easily buried in the paint. There is a limit to increasing the friction coefficient of the surface coat layer. Therefore, the particle size of the hard particles is set to 1
If it is increased to about 00 μm, hard particles are less likely to be buried in the paint. However, when the particle size of the hard particles is increased, the thickness of the surface coat layer is small, and the surface coat layer cannot exert sufficient holding power to hold the hard particles, so that the hard particles of the surface coat layer are easily peeled off, Peripheral parts may be damaged or the friction characteristics during long-term use may be reduced.

Therefore, it is desirable to increase the thickness of the surface coat layer as a countermeasure. However, when the coating is applied to a thickness of about 40 μm or more in the case of spray coating, the coating is liable to drips during spray coating, resulting in high quality. Cannot form a surface coat layer. In addition, when the particle size of the hard particles is increased, the hard particles tend to precipitate in the paint, and it is difficult to form a surface coat layer in which the hard particles are uniformly distributed.

An object of the present invention is to provide a method of forming a surface coat layer having excellent friction characteristics and durability in a metal paper feed roller or a paper feed roller made of synthetic resin, and a metal or synthetic resin paper feed having excellent friction characteristics. Is to provide rollers.

[0007]

According to a first aspect of the present invention, there is provided a method of forming a surface coat layer for a paper feed roller, comprising: applying a synthetic resin powder containing hard particles having a particle size of 60 to 150 μm to a surface of a metal roller member; A first step of powder coating; and a second step of baking the synthetic resin powder on the surface of a roller member to form a synthetic resin coat layer having a thickness of 40 to 75 μm containing the hard particles. It is characterized by having.

In a first step, a synthetic resin powder containing hard particles having a particle diameter of 60 to 150 μm is electrostatically powder-coated on the surface of a metal roller member, and then in a second step, the synthetic resin powder is coated. Is baked on the surface of the roller member to form a synthetic resin coat layer containing the hard particles and having a thickness of 40 to 75 μm.

When the particle size of the hard particles is smaller than 60 μm, the lower limit of the particle size is set to 60 μm because the hard particles are easily buried in the synthetic resin coating layer. When the particle size of the hard particles is larger than 150 μm, it becomes difficult to uniformly distribute the hard particles during electrostatic powder coating due to the influence of gravity acting on the hard particles.
And The thickness of the surface coat layer is set to about 1 /
If it is set to about 2, the hard particles are hardly peeled off, and sufficient durability can be secured.

In addition, in electrostatic powder coating, the film thickness tends to be large, and it is difficult to form a surface coat layer having a film thickness of less than 40 μm. Therefore, the lower limit of the film thickness is set to 40 μm. In addition, if the hard particles are embedded in the surface coat layer in a state in which about 1/2 of the hard particles are embedded, the maximum particle size of the hard particles is 150 μm in view of the fact that the hard particles do not peel off and the durability can be secured. The upper limit of the thickness of the coat layer is set to 75 μm.

According to a second aspect of the present invention, there is provided a method for forming a surface coat layer on a paper feed roller, comprising: a first step of forming a conductive film on the surface of a synthetic resin roller member; A second step of electrostatic powder coating of a synthetic resin powder containing hard particles having a thickness of about 150 μm, and then baking the synthetic resin powder on the surface of the roller member so that the film thickness containing the hard particles is 3
A third step of forming a synthetic resin coat layer having a thickness of 0 to 75 μm.

According to the second aspect of the present invention, since the surface of the synthetic resin roller member is formed by electrostatic powder coating on the surface thereof, in the first step, the surface of the synthetic resin roller member is electrically conductive. Form a coating. After forming the conductive film in this manner, a surface coat layer is formed in the same manner as a metal roller member (that is, in the same manner as in claim 1). That is, in the second step, a synthetic resin powder containing hard particles having a particle diameter of 60 to 150 μm is electrostatically powder-coated on the surface of the roller member on which the conductive film is formed, and then the synthetic resin is coated in the third step. The powder is baked on the surface of the roller member to form a synthetic resin coat layer containing the hard particles and having a thickness of 30 to 75 μm. The particle size of the hard particles and the thickness of the surface coat layer are the same as those described in the first aspect.

According to a third aspect of the present invention, in the paper feed roller for feeding paper, the surface of the metal roller member contains hard particles having a particle diameter of 60 to 150 μm and a film thickness of 40 to 75 μm.
It is characterized in that a synthetic resin coating layer of μm is formed.

As in the first aspect, the hard particles have a particle size of 60
If it is less than μm, the hard particles are likely to be buried in the synthetic resin coating layer, so the lower limit of the particle size is set to 60 μm. When the particle size of the hard particles is larger than 150 μm, it becomes difficult to uniformly distribute the hard particles due to the influence of gravity acting on the hard particles. Therefore, the upper limit of the particle size is set to 150 μm.
When the thickness of the surface coat layer is set to about 1/2 of the particle diameter of the hard particles, the hard particles are hardly peeled off, and sufficient durability can be secured.

Therefore, the surface coat layer is formed by electrostatic powder coating. However, in the case of electrostatic powder coating, the film thickness tends to be large, and the film thickness is reduced to 40 μm.
Since it is difficult to form a surface coat layer having a thickness of less than m, the lower limit of the film thickness is set to 40 μm. When about half of the hard particles are buried in the surface coat layer, the maximum particle size of the hard particles is 150 μm in view of the fact that the hard particles do not peel and the durability can be ensured. Is set to 75 μm.

According to a fourth aspect of the present invention, in the paper feed roller for feeding paper, the surface of the synthetic resin roller member contains hard particles having a particle size of 60 to 150 μm and a film thickness of 40 to 150 μm.
A 75 μm synthetic resin coating layer is formed. Except that the paper feed roller is made of a roller member made of synthetic resin, it is the same as claim 3. Since it is composed of a synthetic resin roller member, it can be manufactured at a significantly lower cost than a paper feed roller composed of a metal roller member. Note that a structure in which a metal pipe material is incorporated inside a roller member made of synthetic resin may be used.

[0017]

Next, an embodiment of the present invention will be described with reference to the drawings. As shown in FIG.
The printer 1 is an ink jet printer, and a space for moving the carriage 3 is provided on the upper surface side portion of the main body case 2.
And the carriage 3 is reciprocally movable left and right. The carriage 3 is moved and driven by a stepping motor via a pair of pulleys and a timing belt having both ends connected to the carriage 3. For example, four color ink cassettes 7a to 7d are detachably mounted on the carriage 3. The sheet P is supplied from a tray 8, is fed by a sheet feed roller 9 and a pressing roller above the sheet feed roller 9, and printing is performed from a print head of the carriage 3 reciprocating on the sheet.

Next, the structure of the paper feed roller 9 will be described. As shown in FIGS. 2 and 3, the paper feed roller 9 includes a metal roller member 10 and a surface coat layer 12 including hard particles 11 formed on the surface of the roller member 10. The hard particles 11 for increasing the friction coefficient of the paper feed roller 9 are made of, for example, alumina, and the particle size of the hard particles 11 is 60 to 150 μm. However, hard particles 11
May be hard particles of various ceramics other than alumina, glass particles, diamond particles, or hard abrasive grains.

The surface coating layer 12 is a coating layer of a synthetic resin (for example, an epoxy resin or an acrylic resin) having excellent rigidity, and has a thickness of 40 to 75 μm. However, in order to prevent the hard particles 11 from peeling off from the surface coat layer 12 during use of the paper feed roller 9, the thickness of the surface coat layer 12 should be set to about １ ／ of the particle diameter of the hard particles 11. desirable. When the thickness of the surface coat layer 12 is significantly larger than about 1/2 of the particle size of the hard particles 11,
The powder of the electrostatic powder coating described later also adheres to the outer surfaces of the hard particles 11 and is baked, which undesirably causes a reduction in friction coefficient.

Here, a method of forming the surface coat layer 12 will be described. In a first step, a roller member 10 is manufactured by cutting and polishing a steel roller material. In the next second step, the roller member 10 is grounded (grounded) while the roller member 10 is set on a rotating device and rotated at a predetermined low speed.
The electrostatic powder coating is performed using an electrostatic powder coating device.

In this electrostatic powder coating, powder for electrostatic powder coating in which about 15 to 20% by weight of alumina fine powder is blended with fine powder of the above-mentioned synthetic resin paint is used for several thousand to While being charged to 10,000 volts, the powder is discharged from the mouse for electrostatic powder coating toward the roller member 10, and the coating powder is discharged by the electrostatic attraction force acting between the roller member 10 and the powder.
Is adsorbed on all surfaces of At this time, the amount of powder supplied per unit time from the mouse, the voltage applied to the powder,
The film thickness of the surface coat layer 12 can be set to a desired thickness of 40 μm or more using the processing time for performing the electrostatic powder coating as a parameter.

In the next third step, the roller member 10 on which the electrostatic powder coating has been performed is placed in a heating furnace, and the roller member 10 is left for about 20 minutes.
The powder is heated to a temperature of 80 to 200 [deg.] C. and the powder is baked on the surface of the roller member to form a surface coat layer 12 having a thickness of 40 to 75 [mu] m including hard particles 11 of 60 to 150 [mu] m in diameter.

When the particle size of the hard particles 11 is less than 60 μm, the lower limit of the particle size is set to 60 μm because the hard particles 11 are easily buried in the surface coat layer 12. When the particle size of the hard particles 11 is larger than 150 μm, the hard particles 11
Is difficult to distribute uniformly, so the upper limit of the particle size is set to 150 μm. If the thickness of the surface coat layer 12 is set to about 1/2 of the particle size of the hard particles 11, the hard particles 11
Is difficult to peel off and sufficient durability can be secured.
It is desirable that the film thickness be about 1/2 of the particle diameter of the hard particles 11.

In addition, in electrostatic powder coating, the film thickness tends to be large, and it is difficult to form the surface coat layer 12 having a film thickness of less than 40 μm. Therefore, the lower limit of the film thickness is set to 40 μm.
Also, about a half of the hard particles 11 are
In the state where the hard particles 11 are embedded, since the maximum particle diameter of the hard particles 11 is 150 μm in view of the fact that the hard particles do not peel off and the durability can be secured, the upper limit of the thickness of the surface coat layer 12 is set to 75 μm. .

Here, a supplementary explanation will be given. Although the particle size of the hard particles 11 is set to 60 to 150 μm,
Instead of using the powder for electrostatic powder coating in which the hard particles 11 having a particle size of m are mixed, the hard particles 11 having a substantially predetermined particle size in the range of 60 to 150 μm (for example, 90 to 100 μm). This also applies to the thickness of the surface coat layer 12 of 40 to 75 μm, which does not mean that the thicknesses of 40 to 75 μm are mixed, but a substantially predetermined thickness within the range of 40 to 75 μm (for example, , 45 to 50 μm), and preferably has a predetermined thickness equal to about 約 of the particle diameter of the hard particles 11.

Since the lower limit of the thickness of the surface coat layer 12 is about 40 μm, when the particle size of the hard particles 11 is 60 μm, more than half of the hard particles 11 are covered by the surface coat layer 12. Less preferred, hard particles 11
Is more desirably 80 μm or more. In the paper feed roller 9 described above, the paper feed roller 9
The hard coat 11 having a particle diameter of 60 to 150 μm is contained in the surface coat layer 12 of
5 μm and a thickness of about ５ of the particle size of the hard particles 11, so that the hard particles 11 are not covered with the coating film,
In addition, since the protrusion amount of the hard particles 11 from the surface coat layer 12 also increases, the surface coat layer 1 having a large friction coefficient
It becomes 2.

Moreover, since the thickness of the surface coat layer 12 is large, about a half of the hard particles 11
The hard particles 11 are hardly peeled off even when the paper feed roller 9 is used for a long time, and the durability is excellent, and the paper feed performance is improved. Dramatically improved. In the method for forming the surface coat layer of the paper feed roller 9, the surface of the metal roller member 10 is electrostatic powder-coated with a synthetic resin powder containing hard particles 11 having a particle size of 60 to 150 μm, Since the synthetic resin powder is baked on the surface of the roller member 10 to form the synthetic resin coat layer 12 including the hard particles 11 and having a thickness of 40 to 75 μm, the following effects can be obtained.

That is, the particle size of the hard particles 11 is 60 to 150.
μm, the hard particles 11 are not buried in the surface coat layer 12 and the surface coat layer 1 having a large friction coefficient
2 can be reliably formed. The surface coating layer 1 is formed by electrostatic powder coating of a synthetic resin powder containing hard particles 11.
2, the surface coat layer 12 having a large thickness can be formed, and about half of the hard particles 11 on the roller side are covered with the surface coat layer 12, so that the hard particles 11
Is increased, and the hard coat 11 is hardly peeled off, and the surface coat layer 12 having excellent durability can be formed.

Next, a description will be given of an experiment conducted for examining the friction characteristics of the paper feed roller manufactured as described above and the paper feed roller according to the comparative example, and the results thereof. Regarding the experimental device used for measuring the friction coefficient of the paper feed roller 9, as shown in FIG.
, A weight 22 of 50 gw, and a paper material P are set as shown in the figure, and the load is measured by the force gauge 20 while rotating the paper feed roller 21 in a counterclockwise direction by a rotary driving device (not shown). Paper feed roller 21 based on load data
Was measured for friction coefficient. The friction coefficient of the surface coat layer of the paper feed roller 21 obtained from the experimental results is as shown in FIGS.

The paper materials used in the experiment were special paper, which is ordinary high-quality paper, a film made of synthetic resin, and bond paper. Sample A in the figure has a particle size of 20 to
This is a paper feed roller having a surface coat layer (thickness: 30 to 40 μm) formed by spray coating an epoxy-based paint containing 40 μm abrasive grains. Sample B has a particle size of 20-4.
This is a paper feed roller having a surface coat layer (thickness: 30 to 40 μm) in which a powder of an epoxy paint containing 0 μm abrasive grains is formed by a special coating method substantially similar to electrostatic powder coating.
Sample C is a surface coating layer (film thickness of 60 to 80 μm) formed by applying an epoxy-based coating powder containing abrasive grains having a particle size of 80 to 90 μm by a special coating method substantially similar to electrostatic powder coating.
Paper feed roller.

In the experiment before the endurance, the load data was measured 10 times for the special paper, and then the load was measured for the film.
The measurement of the load data was performed twice. In the durability test, the dedicated paper was rubbed and slid for 90 seconds before measuring the load data, then rubbed against the bond paper for 90 s and then the load data was measured. Load data was measured after friction sliding. In the post-durability experiment, the load data was measured ten times for the specialty paper, and then the load data was measured ten times for the film.

FIGS. 5 and 6 show the data of the coefficient of friction of the special paper before and after endurance, and FIGS. 7 and 8 show the data of the coefficient of friction of the film before and after endurance. As can be seen from FIGS.
(Corresponding to the paper feed roller of claim 3 of the present application)
Compared with the samples A and B according to the comparative example, a significantly larger friction coefficient is realized.

Next, a modified embodiment in which the above-described embodiment is partially modified will be described. The metal roller member 10
Instead of using a roller member made of a synthetic resin (for example, an epoxy resin, an acrylic resin, or another hard synthetic resin), a method of forming a surface coat layer containing hard particles on the surface thereof, and manufacturing by the method The paper feed roller described above will be described.

As shown in FIGS. 9 and 10, the paper feed roller 9A includes a roller member 10A made of synthetic resin, a conductive film 13 formed on the entire surface thereof,
3 is a surface coat layer 12 formed on the entire surface and is composed of a surface coat layer 12 containing hard particles 11.
The hard particles 11 have a particle size of 60 to 1 similar to that of the embodiment.
The surface coat layer 12 is formed of alumina having a thickness of 50 μm and a thickness of 40 to 75 μm. This paper feed roller 9
The operation and effect of A are the same as the operation and effect of the paper feed roller 9 of the above embodiment. In addition, since the roller member 10A made of synthetic resin is used, the manufacturing cost of the roller member 10A can be significantly reduced.

In manufacturing the paper feed roller 9A, in the first step, a roller member 10A made of synthetic resin is manufactured by injection molding, and in the next step, a predetermined conductive paint is applied to the entire surface of the roller member 10A. The conductive film 13 having a predetermined thickness is formed by applying the film having a thickness of and drying the film. In this way, in a state where the conductive film 13 is formed on the entire surface of the roller member 10A, electrostatic powder coating can be performed in the same manner as in the case of the metal roller member 10,
Similarly to the above embodiment, the surface of the roller member 10A is electrostatically coated with a synthetic resin powder containing hard particles 11 having a particle size of 60 to 150 μm, and then the synthetic resin powder is coated on the surface of the roller member 10A. To a thickness of 4 including the hard particles 11
The synthetic resin coat layer 12 having a thickness of 0 to 75 μm is formed. According to this method, by applying electrostatic powder coating to the roller member 10A made of synthetic resin, the paper feed roller 9 having a large friction coefficient can be obtained.
A can be manufactured.

Here, the above-described embodiments and modifications are merely examples of the present invention, and various modifications can be made without departing from the spirit of the present invention.

[0037]

According to the first aspect of the present invention, the surface of the metal roller member is electrostatically powder-coated with a synthetic resin powder containing hard particles having a particle size of 60 to 150 μm, and then the synthetic resin powder is coated. Since the body is baked on the surface of the roller member to form a synthetic resin coating layer containing hard particles and having a thickness of 40 to 75 μm, the following effects can be obtained.

Since the hard particles have a large particle size of 60 to 150 μm, the hard particles are not buried in the surface coat layer, and a surface coat layer having a large friction coefficient can be formed. Since the surface coat layer is formed by electrostatic powder coating of synthetic resin powder containing hard particles, it is possible to form a surface coat layer with a large thickness, and about half of the hard particles on the roller side are surface coated. With the structure covered with the layer, the holding force for holding the hard particles is increased, and the surface coat layer having excellent durability, in which the hard particles are hardly peeled off, can be formed.

According to the second aspect of the present invention, after the conductive film is formed on the surface of the synthetic resin roller member, the synthetic resin powder containing hard particles having a particle size of 60 to 150 μm is formed on the surface of the roller member. The body is subjected to electrostatic powder coating, and then a synthetic resin powder is baked on the surface of the roller member so that the film thickness including the hard particles is 4
Since the synthetic resin coating layer having a thickness of 0 to 75 μm is formed, the same effect as that of claim 1 is obtained, and a paper feed roller made of an inexpensive synthetic resin and having excellent friction characteristics and durability is manufactured. be able to.

According to the third aspect of the present invention, since the hard particles have a large particle size of 60 to 150 μm, the hard particles are not buried in the surface coat layer, and the paper feed having the surface coat layer having a large friction coefficient is prevented. Become a roller. Since the surface coat layer has a thickness of 40 to 75 μm and is a large surface coat layer, it becomes a surface coat layer that covers about half of the hard particles on the roller side, and the holding force for holding the hard particles increases.
A paper feed roller having a surface coat layer with excellent durability, in which hard particles are hardly peeled off, is obtained.

According to the fourth aspect of the present invention, the only difference from the paper feed roller of the third aspect is that a roller member made of synthetic resin is used instead of the metal roller member. In addition to the effect similar to that of the item 3, since the roller member made of synthetic resin is used, it can be manufactured at a much lower cost than the paper feed roller composed of a metal roller member.

[Brief description of the drawings]

FIG. 1 is a perspective view of a printer according to an embodiment of the present invention.

FIG. 2 is a perspective view of a paper feed roller.

FIG. 3 is an enlarged sectional view of a main part of a paper feed roller.

FIG. 4 is a configuration diagram of an experimental apparatus used for friction coefficient measurement.

FIG. 5 is a table of a coefficient of friction for a special paper for a plurality of samples.

FIG. 6 is a diagram showing a coefficient of friction of a plurality of samples with respect to special paper.

FIG. 7 is a chart of the coefficient of friction for a film for a plurality of samples.

FIG. 8 is a diagram showing a coefficient of friction with respect to a film for a plurality of samples.

FIG. 9 is a perspective view of a paper feed roller according to a modified embodiment.

FIG. 10 is an enlarged sectional view of a main part of the paper feed roller of FIG. 9;

[Explanation of symbols]

 9, 9A paper feed roller 10, 10A roller member 11 hard particles 12 surface coat layer 13 conductive film

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3F049 AA10 CA12 CA13 CA14 LA02 LA05 LA06 LA07 LB03 4D075 AA09 AB09 CA22 DA15 DB01 DC18 DC27 EA02 EB11 EB31 EB57

Claims (4)

[Claims] 1. A metal roller member having a particle diameter of 60 on its surface.
A first step of electrostatic powder coating of a synthetic resin powder containing hard particles of about 150 μm, and then baking the synthetic resin powder on the surface of the roller member;
A second step of forming a synthetic resin coat layer containing the hard particles and having a thickness of 40 to 75 μm, and a method of forming a surface coat layer of a paper feed roller. 2. A first step of forming a conductive film on the surface of a synthetic resin roller member. Next, a synthetic resin powder containing hard particles having a particle size of 60 to 150 μm is formed on the surface of the roller member. A second step of applying an electric powder coating; and a third step of baking the synthetic resin powder on the surface of the roller member to form a synthetic resin coat layer having a thickness of 40 to 75 μm containing the hard particles. A method for forming a surface coat layer of a paper feed roller, comprising: 3. A paper feeding roller for feeding paper, characterized in that a synthetic resin coating layer containing hard particles having a particle size of 60 to 150 μm and having a thickness of 40 to 75 μm is formed on a surface of a metal roller member. And a paper feed roller. 4. A paper feed roller for feeding paper, wherein a particle diameter of the synthetic resin roller member is 60 to 150 μm.
A paper feed roller comprising a synthetic resin coat layer having a thickness of 40 to 75 μm containing m hard particles.