Abstract: In the present invention, the platen bar is compositely formed of three materials. For a sole layer, a material is used which has high hardness and strength, and has a property that the repulsion against the impact of the print wires is large. For an elastic layer, a material is used which transmits less vibration to the platen base in the print operation and absorbs the impact when the wires of a printhead strike the sole layer. For platen bases, a material is used which has a very high hardness, a high molding precision, and less dimensional change due to temperature change or change with time. The elastic layer is exposed on the surface and a gap roller is positioned at the exposure location. With this, the occurrence of the dent by the gap roller can be prevented when the printing on a copy form is performed.

Abstract: There is provided a paper feed roller capable of being used for delivering and feeding paper, which is high in coefficient of friction, has sufficient hardwearing properties with the coefficient of friction not affected by the change in environment of temperature and humidity, is low in ink transferability and is small in change in passage of year of the coefficient of friction of the surface.A coating layer 5 formed of an elastic material such as rubber is formed on an surface of a core material 4 molded of a foamed material such as sponge, and a bonding agent 6 having an elasticity such as denatured silicon is coated on the surface of the coating layer 5 so that ceramic particles 7 are fixed without clearance to provide a paper feed roller 1. Alternatively, the bonding agent 6 is directly coated on the surface of the core material 4 molded of a pliable material such as soft rubber and sponge so that the ceramic particles 7 are fixed without clearance to provide the paper feed roller 9.

Abstract: A paper feed roller for delivering and feeding paper, which has a high coefficient of friction that is not affected by changes in temperature or humidity, good hardwearing properties, and is low in ink transferability. The paper feed roller includes a coating layer formed of an elastic material such as rubber which is formed on a surface of a core material molded of a foamed material such as sponge. A bonding agent having an elasticity such as denatured silicon is coated on the surface of the coating layer. Ceramic particles are embedded and fixed in the bonding agent In an alternative embodiment the bonding agent is directly coated on the surface of core material which is molded from a pliable material such as soft rubber and sponge.