Electrophotographic recording apparatus using developing device with one-component type developer and having combination of charge injection effect and conductive contact type charger

An electrophotographic recording apparatus, comprising:

• a photosensitive body;
• a conductive contacting type charger for producing an electrically-charged area on said photosensitive body;
• an optical writer for forming an electrostatic latent image on the electrically-charged area of said body;
• a developer for electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• a transfer member for electrostatically transferring the charged visible image developed by said developer from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity,
• wherein the developer transfer efficiency is greater than about 80%,
• wherein said developer includes a conductive developing roller member for entraining the developer to form a developer layer therearound and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member,
• wherein said transfer member includes a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member, and
• wherein an optical density of the transferred image is greater than 1.2.

An electrophotographic recording apparatus, comprising:

• a photosensitive body;
• a conductive contacting type charger for producing an electrically-charged area on said photosensitive body;
• an optical writer for forming an electrostatic latent image on the electrically-charged area of said body;
• a developer for electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• a transfer member for electrostatically transferring the charged visible image developed by said developer from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity,
• wherein the developer transfer efficiency is greater than about 80%,
• wherein said developer includes a conductive developing roller member for entraining the developer to form a developer layer therearound and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member,
• wherein said transfer member includes a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member, and
• wherein an average charge density for the developer is in the range of 7-17 μC/g.

A method for operating an electrophotographic recording apparatus, comprising the steps of:

• providing a photosensitive body;
• using a conductive contacting type charger for electrically-charging an area on said photosensitive body;
• forming an electrostatic latent image on the electrically-charged area of said body;
• electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• electrostatically transferring the charged visible image from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity, so that the developer transfer efficiency is greater than about 80%,
• wherein the optical density of the transferred image is greater than 1.2,
• wherein said developing step includes using a conductive developing roller member for entraining the developer to form a developer layer around the body, and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member, and
• wherein said transferring step includes using a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member.

A method for operating an electrophotographic recording apparatus, comprising the steps of:

• providing a photosensitive body;
• using a conductive contacting type charger for electrically-charging an area on said photosensitive body;
• forming an electrostatic latent image on the electrically-charged area of said body;
• electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• electrostatically transferring the charged visible image from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity, so that the developer transfer efficiency is greater than about 80%,
• wherein said developing step includes using a conductive developing roller member for entraining the developer to form a developer layer around the body, and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member,
• wherein said transferring step includes using a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member, and
• wherein the electrostatic transferring step provides an optical density of the transferred image greater than 1.2.

A method for operating an electrophotographic recording apparatus, comprising the steps of:

• providing a photosensitive body;
• using a conductive contacting type charger for electrically-charging an area on said photosensitive body;
• forming an electrostatic latent image on the electrically-charged area of said body;
• electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• electrostatically transferring the charged visible image from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity, so that the developer transfer efficiency is greater than about 80%,
• wherein said developing step includes using a conductive developing roller member for entraining the developer to form a developer layer around the body, and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member,
• wherein said transferring step includes using a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member, and
• wherein an average charge density for the developer is in the range of 7-17 μC/g.

An electrophotographic recording apparatus, comprising:

• a photosensitive body means;
• conductive contacting type charger means for producing an electrically-charged area on said photosensitive body means;
• optical writing means for forming an electrostatic latent image on the electrically-charged area of said body means;
• developing means for electrostatically developing the electrostatic latent image of said body means in an environment of 20-80% (g/Kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• transferring means for electrostatically transferring the charged visible image developed by said developing means from said body means to a recording medium in an environment of 20-80% (g/Kg) relative humidity,
• wherein the developing means transfer efficiency is greater than about 80%,
• wherein said developing means includes a conductive developing roller member for entraining the developer to form a developer layer therearound and for bringing the developer layer to said body means for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect means for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member, and
• wherein said transferring means includes a conductive transfer roller member in contact with said body means, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body means and said conductive transfer roller member,
• wherein said developing roller member is formed as a conductive foam rubber roller member, and said regulating blade member is formed as a conductive stainless steel plate member,
• wherein said conductive transfer roller member is formed as a conductive foam rubber roller member,
• wherein said conductive contacting type charger means is formed as a conductive rotary brush type charger, and
• wherein an optical density of the transferred image is greater than 1.2.

An electrophotographic recording apparatus, comprising:

• a photosensitive body;
• a conductive contacting type charger for producing an electrically-charged area on said photosensitive body;
• an optical writer for forming an electrostatic latent image on the electrically-charged area of said body;
• a developer for electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• a transfer member for electrostatically transferring the charged visible image developed by said developer from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity
• wherein the optical density of the transferred image is greater than 1.2,
• wherein the developer transfer efficiency is greater than about 80%,
• wherein said developer includes a conductive developing roller member for entraining the developer to form a developer layer therearound and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member,
• wherein an average charge density for the developer is in the range of 7-17 μC/g, and
• wherein said transfer member includes a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member.

A method for operating an electrophotographic recording apparatus, comprising the steps of:

• providing a photosensitive body;
• using a conductive contacting type charger for electrically-charging an area on said photosensitive body;
• forming an electrostatic latent image on the electrically-charged area of said body;
• electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• electrostatically transferring the charged visible image from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity, so that the optical density of the transferred image is greater than 1.2, and so that the developer transfer efficiency is greater than about 80%,
• wherein said developing step includes using a conductive developing roller member for entraining the developer to form a developer layer around the body, and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member, so that the average charger density for the developer is in the range of 7-17 μC/g, and
• wherein said transferring step includes using a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member.

An electrophotographic recording apparatus, comprising:

• a photosensitive body;
• a conductive contacting type charger for producing an electrically-charged area on said photosensitive body;
• an optical writer for forming an electrostatic latent image on the electrically-charged area of said body;
• a developer for electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• a transfer member for electrostatically transferring the charged visible image developed by said developer from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity,
• wherein the developer transfer efficiency is greater than about 80%,
• wherein said developer includes a conductive developing roller member for entraining the developer to form a developer layer therearound and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member,
• wherein an average charge density for the developer is in the range of 7-17 μC/g, and
• wherein said transfer member includes a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member.

A method for operating an electrophotographic recording apparatus, comprising the steps of:

• providing a photosensitive body;
• using a conductive contacting type charger for electrically-charging an area on said photosensitive body;
• forming an electrostatic latent image on the electrically-charged area of said body;
• electrostatically developing the electrostatic latent image of said body in an environment of 20-80% (g/kg) relative humidity as a charged visible image with an electrostatically-charged one-component developer;
• and
• electrostatically transferring the charged visible image from said body to a recording medium in an environment of 20-80% (g/kg) relative humidity, so that the developer transfer efficiency is greater than about 80%,
• wherein said developing step includes using a conductive developing roller member for entraining the developer to form a developer layer around the body, and for bringing the developer layer to said body for the development of the latent image, a conductive regulating blade member resiliently engaged with said developing roller for uniformly regulating a thickness of the developer layer formed therearound, and a charge injection effect member for electrically charging the developer layer by applying a developer bias voltage to said conductive developing roller member and electric energy to said regulating blade member,
• wherein an average charge density for the developer is in the range of 7-17 μC/g, and
• wherein said transferring step includes using a conductive transfer roller member in contact with said body, and an electric source for applying an electric energy to said conductive transfer roller member to give the recording medium an electric charge having a polarity opposite to that of the charged visible image, during a passage of the recording medium through a nip between said body and said conductive transfer roller member.