JPS5851262B2 - Silicone oil-added heat fixing roll for electronic copying machines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a toner heat fixing roll of a type in which silicone oil is added to the roll surface in an electronic copying machine, and in particular improves the clarity of a copied image by improving the elasticity of the roll surface. The purpose is to provide a means.

Conventionally, among the rolls used for toner heat fixing in electronic copying machines, the type of roll in which silicone oil is added to the roll surface from the outside to improve the toner release properties is
On the elastic layer made of heat-resistant silicone rubber fixed and laminated on the core metal, there is a 0.4
A cylinder with a relatively thin wall thickness of ~1.0 mm is adhered as a skin, or a similarly thin oil-resistant silicone rubber is also vulcanized as a skin together with an underlying heat-resistant silicone rubber layer. .

However, although the heat-resistant silicone rubber layer that is the lower layer has sufficient soft elasticity, the skin layer is hard, so
A sufficient nip width a between the pressure contact surfaces of the two rolls cannot be obtained.

The inventor's research has revealed that due to an insufficient nip width Iζ, the toner is incompletely melted and as a result, the copied image becomes unclear. It is the purpose of this invention to remove this, and this purpose has been achieved by constructing the roll as described below.

That is, the roll of the present invention has a 20 to 30% elastic layer made of heat-resistant silicone rubber that is laminated and fixed to a core metal, and then liquid fluorosilicone rubber or liquid fluororubber is baked on top of the elastic layer made of heat-resistant silicone rubber.
It has a skin layer with a thickness of 0μ.

Next, examples of manufacturing such rolls include aluminum (A5056) or stainless steel (SUS430).
) heat-resistant silicone rubber DY-3 made by Toshi on top of the core bar 1.
The cylinder 2 of 2 is fitted and fixed at the same time as vulcanization, and a polysiloxane oil-resistant primer XE manufactured by Toshiba Silicone is applied to the cylindrical surface.
Apply 9214, then pivot the core metal 1 and apply 1500~
While rotating at 2000 rpm, spray liquid fluororubber (Aflas 2323) manufactured by Asahi Glass at room temperature, and
After leaving it at room temperature for a minute, bake it at 150℃ for 15 minutes.

The hardness of the roll surface of the roll thus obtained is JIS hardness of 20 to 30 degrees, and the hardness of the roll surface of the above-mentioned conventional roll having a surface layer of fluororesin Teflon is JIS hardness of 70 to 80 degrees. Also, even those with a surface layer of fluorosilicone rubber are much softer than those with a JIS hardness of 50 to 70 degrees.

Therefore, even if the pressing force between the pair of rolls is small, an appropriate nip width can be obtained, and when the roll surface detaches from the pressing surface due to rotation and returns to its original arcuate shape, the return at the separation point is instantaneous. Therefore, the toner is completely melted and the copied image becomes clear.

Note that instead of liquid fluororubber for forming the skin layer, liquid fluorosilicone rubber (for example, 5E1550 manufactured by Hatoshi Co., Ltd.) is used.
The above-mentioned results are the same when using .

Thus, according to the present invention, it is possible to provide a silicone oil-added heat fixing roll that can provide copied images with much higher definition than conventional ones.

[Brief explanation of drawings]

FIG. 1 is an axial sectional view of a heat fixing roll according to the present invention, and FIG.
Each of the figures shows the manner in which a pair of heat fixing rolls having an elastic layer are brought into contact with each other, and FIG. 3 is a diagram showing the manner in which a roll having an elastic layer and a metal roll are brought into contact with each other. 1 is a core metal, 2 is a heat-resistant silicone rubber layer, 3 is a layer of polysiloxane oil-resistant primer, 4 is a skin layer, 5 is a roll with an elastic layer, 6 is a metal roll, a is the nip width, and b is the breakaway point It is.

Claims (1)

[Claims] 1. An electronic copying machine having a skin layer with a thickness of 20 to 300 μm, in which liquid fluorosilicone rubber or liquid fluororubber is baked on an elastic layer made of heat-resistant silicone rubber that is laminated and adhered to a core metal. Heat fixing roll with silicone oil added.