Device for fixing an image on a recording medium
AssigneeRicoh Company, Ltd.
InventorTakeo Tsukamoto
Life of this patent
Estimating the term…
Abstract
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in the solvent is disclosed. A potential difference is set up between the surface of a contact member and that of a pressing member via a recording medium in order to fix the colored particles on the recording medium. The device has a simple, miniature configuration and a high fixing ability.
Claims38
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- said contact member comprising a heat roller made up of a conductive roller serving as a conductive portion, and a high resistance, ceramic thin film formed on a surface of said conductive roller;
- said pressing member being formed of an at least semiconductive material;
- wherein a current is caused to flow between said conductive roller and said pressing member via the recording medium.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member including a high resistance, ceramic thin film on its surface for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- wherein a potential difference is set up between a surface of said contact member and a surface of said pressing member via the recording medium.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- wherein a potential difference is set up between a surface of said contact member and a surface of said pressing member via the recording medium, and
- wherein before the image carried on the recording medium contacts said contact member, discharge is caused to occur between the surface of said contact member and the surface of said pressing member for feeding a charge to the colored particles forming said image.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- and
- heating means for heating the surface of said contact member;
- wherein a potential difference is set up between a surface of said contact member and a surface of said pressing member via the recording medium, and
- wherein the potential difference above a discharge start voltage is set up between the surface of said contact member and the surface of said pressing member to thereby cause discharge to occur, and wherein when the recording medium is absent and when said contact member is warmed up to a fixing temperature, a value produced by differentiating said potential difference for a unit axial length by a current is selected to be greater than 1.times.10.sup.-7 A.V.sup.-1.m.sup.-1 inclusive, but smaller than 1.times.10.sup.-4 A.V.sup.-1.m.sup.-1 inclusive.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- wherein a potential difference is set up between a surface of said contact member and a surface of said pressing member via the recording medium, and
- wherein an anode oxide film of aluminum is formed on a surface layer of said contact member.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member including a high resistance, ceramic thin film on its surface for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- wherein a current is caused to flow between a surface of said contact member and a surface of said pressing member via the recording member.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- wherein a current is caused to flow between a surface of said contact member and a surface of said pressing member via the recording medium, and
- wherein the current is caused to flow by use of a constant current power source.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- wherein a current is caused to flow between a surface of said contact member and a surface of said pressing member via the recording medium, and
- wherein before the image carried on the recording medium contacts said contact member, discharge is caused to occur between the surface of said contact member and the surface of said pressing member for feeding a charge to the colored particles forming said image.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- and
- heating means for heating the surface of said contact member;
- wherein a current is caused to flow between a surface of said contact member and a surface of said pressing member via the recording medium, and
- wherein a potential difference above a discharge start voltage is set up between the surface of said contact member and the surface of said pressing member to thereby cause discharge to occur, and wherein when the recording medium is absent and when said contact member is warmed up to a fixing temperature, a value produced by differentiating said potential difference for a unit axial length by the current is selected to be greater than 1.times.10.sup.-7 A.V.sup.-1.m.sup.-1 inclusive, but smaller than 1.times.10.sup.-4 A.V.sup.-1.m.sup.-1 inclusive.
A device for fixing an image formed on a recording medium by fine colored particles dispersed in a solvent and capable of at least temporarily holding a charge in said solvent, said device comprising:
- a contact member for contacting a first surface of the recording medium carrying the image;
- and
- a pressing member for pressing the recording medium against said contact member via a second surface of said recording medium opposite to the first surface to thereby press the image;
- wherein a current is caused to flow between a surface of said contact member and a surface of said pressing member via the recording medium, and
- wherein an anode oxide film of aluminum is formed on a surface layer of said contact member.
A device for fixing an image formed on a recording medium by a developing liquid in which a carrier is partly or entirely implemented by a nonvolatile solvent, said device comprising:
- a heat roller;
- heat roller drive means for driving said heat roller;
- and
- a plurality of backup rollers sequentially arranged along a circumference of said heat roller;
- wherein said plurality of backup rollers each press the recording medium toward said heat roller with a force which is less than 50 g/cm inclusive for a unit axial length of the backup roller.
Dependencies are inferred from the claim text.