JPH0548203Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a release agent coating device used in fixing devices such as PPC copiers, facsimile machines, and laminators.

(Prior art) In a fixing device such as a PPC copying machine that burns the copy paper by passing the toner transferred to the copy paper between a heating fixing roller and a pressurized elastic roller, the toner and the copy paper are transferred to the rollers of the fixing device such as a PPC copying machine. In order to prevent adhesion, a mold release agent (usually silicone oil) is generally applied (for example, see FIG. 4 below).

It is difficult to uniformly apply this mold release agent to the roller in an appropriate amount, so there is a mold release agent application device as shown in Fig. 5 that uses a porous polytetrafluoroethylene resin for which the applicant has previously applied for a patent. According to this method, it is possible to apply a mold release agent in small amounts of 0.several milligrams per copy, and moreover, over tens of thousands of copies. In this case, the porosity of the tetrafluoroethylene resin porous body is 50%.
~90% is good, and the viscosity of silicone oil is 1000~
Use one with a value of 100,000 cs. The release agent coating device shown in FIG. 5 is used by being attached to either or both of a heating roller and a pressure roller. In FIG. 5, 1 is a housing, and 2 is a porous tetrafluoroethylene resin impregnated with a mold release agent.

(Problems that the device aims to solve) However, the above still has the following problems.

Since the release agent applicator is used in a fixed manner, the load placed on the rollers is large. Also, the surface of the roller may be damaged by toner or paper dust that accumulates on the coating surface.

If a certain amount of toner or paper dust accumulates on the coated surface, it will slip through and the image on the copy paper will become smudged (the cleaning effect is small).

In view of the above, the present invention has been developed in order to solve these problems and to provide a mold release agent application device that can uniformly apply a mold release agent and is easy to manufacture.

The present invention will be explained below in an easy-to-understand manner with reference to illustrative drawings.

(Means for solving the problem) As shown in Fig. 1, the release agent coating device of the present invention has the following features:
It is characterized in that a core bar 4 having a circular cross section is inserted inside a porous tube of tetrafluoroethylene resin, and the porous portions of the tetrafluoroethylene resin are further impregnated with silicone oil as a mold release agent. Note that 3 in FIG. 1 is a porous tube of tetrafluoroethylene resin impregnated with a mold release agent.

In this case, the porous tube 3 and the core bar 4 can be fixed using silicon adhesive or meltable fluororesin, or by cutting a thin groove 5 in the core bar 4 as shown in Fig. 2 from this diameter. It may also be fixed by forcibly inserting a porous tube with a small inner diameter into the groove.

In the above, the porosity of the tetrafluoroethylene resin porous tube and the viscosity of the silicone oil are preferably the same as those described in the prior art section at the beginning.

This is used by being pressed against a heating roller or a pressure roller and being driven by the roller, or by being rotated in the opposite direction to the roller.

(Function) With the above structure, the release agent applicator becomes roller-shaped and can be rotatably supported instead of fixedly supported. Further, toner and paper dust adhering to the coated surface can be easily removed with a blade on the roller-like surface.

(Example) Examples will be described below to help understand the present invention.

The core metal 4 is made of aluminum, L = 340 mm in Fig. 3,
The dimensions were D=14 mm, d=8 mm, W=2 mm, and t=1 mm.

A polytetrafluoroethylene resin porous tube 3 having an inner diameter of 13 mm, an outer diameter of 20 mm, a length of 300 mm and a porosity of 75% was inserted into this to form a roller as shown in FIG. 1. The porous portion of this porous tube was impregnated with 30 g of 30,000 cs of silicone oil (manufactured by Shin-Etsu Chemical: KF#96H) to form a roller-shaped mold release agent coating device as shown in FIG.

This was set on the fixing roller 10 as shown in FIG. 4, and the fixing roller was driven. The speed of the fixing roller surface at this time is 250 mm/sec.

The amount of release agent applied at this time is 0.1 per sheet of copy paper.
It was a small amount of ~0.3 mg, and a stable coating amount was obtained up to 50,000 sheets, with almost no staining on copy paper.

In FIG. 4, 11 is a pressure elastic roller, 12 is copy paper, 13 is a toner, 14 is a heater, and 15 is a separation claw.

(Effects of the invention) As explained above, the invention has the following effects.

The frictional resistance against the fixing roller and pressure roller is small, so the surface of the roller is less likely to be damaged.

The application area is large and the cleaning effect is also great.

The mold release agent can be applied stably over a long period of time.

Since a porous material of tetrafluoroethylene resin is used,
The thickness and pore size distribution of the layer can be made uniform, and the release agent can be applied uniformly.

It is easy to manufacture because a core metal having a circular cross section is inserted into a porous tube of tetrafluoroethylene resin.

[Brief explanation of the drawing]

Figure 1 is a front view (Figure a) and cross-sectional view (Figure b) of the mold release agent applicator of the present invention, and Figure 2 is one shape for fixing the porous membrane and the core metal in the present invention. A front view (Figure a) and a cross-sectional view (Figure b) of the core metal in the example shown in Fig. 3, and a front view (Figure a) and a cross-sectional view (Figure Figure b), Figure 4 is a front view of a fixing device illustrating an embodiment of the present invention;
FIG. 5 illustrates a front view (Fig. a) and a cross-sectional view (Fig. b) of a mold release agent application device previously filed by the present applicant. 3... Release agent-impregnated tetrafluoroethylene resin porous tube, 4... Circular cross-section core bar, 5... Thin groove,
9...Roller-like release agent coating device, 10...Heat fixing roller, 11...Pressure elastic roller, 12...Copy paper, 13...Tonner.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) In a fixing device that prints toner transferred onto copy paper by passing it between a heat fixing roller and a pressure elastic roller, It is a roller-like device that applies a mold release agent to an elastic roller, and a core bar with a circular cross section is inserted into a porous tube of tetrafluoroethylene resin, and the mold is released into the porous portion of the porous tube of tetrafluoroethylene resin. A mold release agent coating device impregnated with a mold release agent. (2) The porosity of the tetrafluoroethylene resin porous tube is 50% to 85%, and the viscosity of the mold release agent is 1000 c.s.
Utility model registration claim number (1) which is 100000c.s.
The mold release agent coating device described in Section 1. (3) The mold release agent coating device according to claim 1, in which a porous tetrafluoroethylene resin tube and a core metal are fixed by adhering them using a silicone adhesive. (4) The mold release agent applicator according to claim (1) of the utility model registration, in which a porous tetrafluoroethylene resin tube and a core are fixed by adhesion using a meltable fluororesin. (5) Connect the polyfluoroethylene resin porous tube and the core metal by using a core metal with a thin groove cut into the core metal, and forcefully insert the porous tube with an inner diameter smaller than the outer diameter of the core metal. The release agent applicator according to claim 1, which is fixed by being inserted into a narrow groove.