US 6,641,760 B2Granted

Method of producing endless-belt-shaped film

AssigneeRicoh Company, Ltd.

InventorsMinoru Matsuo, Hideki Komatsu, Akiko Tanaka, Yuichi Jibiki

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Abstract

A film is made of an insulating matrix resin and an electroconductive material, in which the electroconductive material is dispersed in the insulating matrix resin in such a manner that a surface resistivity of A [Ω] of the film and a volume resistivity of B [Ω·cm] of the film in the direction of a thickness thereof normal to the surface of the film satisfy a relationship of: A>B, and when the film has a thickness of T [cm], the electroconductive material is dispersed in the insulating matrix resin in such a manner that the surface resistivity of A [Ω] of the film and the volume resistivity of B [Ω·cm] of the film satisfy a relationship of; A[Ω]'T [cm]>B [Ω·cm]. This film can be prepared by a centrifugal molding method.

Claims15

Dependent claims

A method of producing an endless-belt-shaped film with a single layer structure comprising an insulating matrix resin and an electroconductive material dispersed in the form of needles in said insulating matrix resin with a longitudinal side of said needles of said electroconductive material being oriented in the direction normal to an external surface of said film, wherein a cross section of each of said needles of said electroconductive material in the direction normal to said external surface of said film is in the shape of a quadrilateral with unequal diagonal lines, and wherein a longer diagonal line is oriented in the direction normal to said external surface of said film and a shorter diagonal line is oriented in the direction normal to said longer diagonal line, comprising the steps of:

dispersing said electroconductive material in a solution of said matrix resin in a solvent to form a dispersion of said electroconductive material in said solution of said matrix resin, and
subjecting said dispersion to centrifugal molding to orient a longitudinal side of said needles of said electroconductive material in the direction normal to an external surface of said film, wherein a cross section of each of said needles of said electroconductive material in the direction normal to said external surface of said film is in the shape of a quadrilateral with unequal diagonal lines, and wherein a longer diagonal line is oriented in the direction normal to said external surface of said film and a shorter diagonal line is oriented in the direction normal to said longer diagonal line,
and removing said solvent therefrom.

Dependencies are inferred from the claim text.

Facts

Application: 09/846,243Filed 2 May 2001 · division
Priority: JP 10-2705598 Sep 1998
Published: US 2001/0023015 A120 Sep 2001
Granted: 4 Nov 2003
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

C08J 5/18
Manufacture of articles or shaped materials containing macromolecular substances: manufacture of films or sheets
Y10T 428/24777
Structurally defined web or sheet [e.g., overall dimension, etc.]: edge feature
Y10T 428/24802
Structurally defined web or sheet [e.g., overall dimension, etc.]: discontinuous or differential coating, impregnation or bond [e.g., artwork,…
Y10T 428/24876
Translucent outer layer: intermediate layer contains particulate material [e.g., pigment, etc.]

Family

Application09/391,526Parent of this division · filed 8 Sep 1999
US 2001/0023015 A1Pre-grant publication · published 20 Sep 2001
US 2002/0172819 A1Published application
US 6,596,383 B2Related patent
US 6,641,760 B2This patent

From the US filing history. Foreign family members aren’t listed.