Image forming apparatus

Claim 2

An image forming apparatus employing image-forming signals for forming an image on a sheet, comprising: a transfer medium having four regions coated with ink arranged serially along the length of said transfer medium, said four regions respectively comprising coatings of yellow, magenta, cyan and black inks, said yellow, magenta and cyan ink regions having substantially the same sizes, said black ink region being different in size from each of said three other regions; holding means for holding said transfer medium; and image forming means for forming an image by applying said cyan, magenta and yellow inks one over another in accordance with color signals representing a color image and for transferring black ink in response to a black-color signal.

Claim 3

An apparatus as claimed in claim 1, wherein the size of said black ink region is greater than the size of any of said yellow, magenta or cyan ink regions.

Claim 4

An apparatus as claimed in claim 2, wherein the size of said black ink region is substantially equal to the size of legal-size paper and the size of each of said yellow, magenta and cyan ink regions is substantially equal to the size of letter-size paper.

Claim 5

An apparatus as claimed in claim 1, wherein the size of said black ink region is less than the size of any of said yellow, magenta or cyan ink regions.

Claim 6

An apparatus as claimed in claim 4, wherein the size of each of said yellow, magenta and cyan ink regions is substantially equal to the size of legal-size paper and the size of said black ink region is substantially equal to the difference between the sizes of legal-size paper and letter-size paper.

Claim 7

A line printer responsive to image-forming signals to form an image on a sheet, comprising: a transfer medium having regions coated with different color inks arranged serially along the length of said transfer medium, there being a region of black ink that is different in size from the other regions, said regions including yellow, magenta and cyan ink regions of substantially the same sizes; holding means for holding said transfer medium; and head means extending transversely of said transfer medium for transferring said yellow, magenta and cyan inks, one over the other, from said transfer medium to the sheet in accordance with color signals representing a color image and for transferring black ink in response to a black-color signal, said head means comprising means for accomplishing said transferring on a line-by-line basis in accordance with the image-forming signals.

Claim 8

A line printer responsive to image-forming signals to form an image on a sheet, comprising: a transfer medium having regions coated with different color inks arranged serially along the length of said transfer medium, there being a region of black ink that is different in size from the other regions, said regions including yellow, magenta and cyan ink regions of substantially the same sizes; holding means for holding said transfer medium; and head means extending transversely of said transfer medium for transferring said yellow, magenta and cyan inks, one over the other, from said transfer medium to the sheet in accordance with color signals representing a color image and for transferring black ink in response to a black-color signal, said head means comprising means for accomplishing said transferring on a line-by-line basis in accordance with the image-forming signals.

Claim 9

An apparatus as claimed in claim 6, wherein the size of said black ink region is greater than the size of any of said yellow, magenta or cyan ink regions.

Claim 10

An apparatus as claimed in claim 7, wherein the size of said black ink region is substantially equal to the size of a larger first size of paper and the size of each of said yellow, magenta and cyan ink regions is substantially equal to the size of a smaller second size of paper.

Claim 11

An apparatus as claimed in claim 6, wherein the size of said black ink region is less than the size of any of said yellow, magenta or cyan ink regions.

Claim 12

An apparatus as claimed in claim 9, wherein the size of each of said yellow, magenta and cyan ink regions is substantially equal to the size of a larger first size of paper and the size of said black ink region is substantially equal to the difference between the sizes of said first size of paper and a smaller second size of paper.

Claim 13

An image forming apparatus for forming an image on a sheet, comprising a transfer apparatus for transferring a color agent to the sheet in accordance with a latent image to form an image on the sheet and a transfer material feeding device receivable by said transfer apparatus, said transfer material feeding device comprising: a transfer material in the form of a sheet having two ends; said color agent being coated on said transfer material and comprising four regions arranged serially along said transfer material, said four regions respectively comprising yellow, magenta, cyan and black inks, said yellow, magenta and cyan ink regions having substantially the same sizes, said black ink region being different in size from each of the other three regions; a pair of roll shafts respectively windingly engaging said two ends of said transfer material, wherein said transfer material may be fed therebetween, a case integrally enclosing said pair of roll shafts and said transfer material, said case having an opening on one side thereof for exposing a portion of said transfer material disposed between said roll shafts, wherein said transfer apparatus comprises a holder and said case further comprises a slit in a surface thereof other than said one side, said slit and said holder comprising means for guiding said transfer material feeding device onto said holder to be held thereby when said transfer material feeding device is set in said transfer apparatus; and image forming means for forming an image by applying said cyan, magenta and yellow inks one over another in accordance with color signals representing a color image and for transferring black ink in response to a black-color signal.

Claim 14

An image forming apparatus for forming an image on a sheet, comprising a transfer apparatus for transferring a color agent to the sheet in accordance with a latent image to form an image on the sheet and a transfer material feeding device receivable by said transfer apparatus, said transfer material feeding device comprising: a transfer material in the form of a sheet having two ends; said color agent being coated on said transfer material and comprising four regions arranged serially along said transfer material, said four regions respectively comprising yellow, magenta, cyan and black inks, said yellow, magenta and cyan ink regions having substantially the same sizes, said black ink region being different in size from each of the other three regions; a pair of roll shafts respectively windingly engaging said two ends of said transfer material, wherein said transfer material may be fed therebetween, a case integrally enclosing said pair of roll shafts and said transfer material, said case having an opening on one side thereof for exposing a portion of said transfer material disposed between said roll shafts, wherein said transfer apparatus comprises a holder and said case further comprises a slit in a surface thereof other than said one side, said slit and said holder comprising means for guiding said transfer material feeding device onto said holder to be held thereby when said transfer material feeding device is set in said transfer apparatus; and image forming means for forming an image by applying said cyan, magenta and yellow inks one over another in accordance with color signals representing a color image and for transferring black ink in response to a black-color signal.

Claim 15

An apparatus as claimed in claim 11, wherein the size of said black ink region is greater than the size of any of said yellow, magenta or cyan ink regions.

Claim 16

An apparatus as claimed in claim 12, wherein the size of said black ink region is substantially equal to the size of a larger first size of paper and the size of each of said yellow, magenta and cyan ink regions is substantially equal to the size of a smaller second size of paper.

Claim 17

An apparatus as claimed in claim 11, wherein the size of said black ink region is less than the size of any said yellow, magenta or cyan ink regions.

Claim 18

An apparatus as claimed in claim 14, wherein the size of each of said yellow, magenta and cyan ink regions is substantially equal to the size of a larger first size of paper and the size of said black ink region is substantially equal to the different between the sizes of said first size of paper and a smaller second size of paper.

Claim 19

In combination: an ink ribbon comprising a continuous medium and discrete regions of ink arranged serially along the length of said continuous medium, each region being spaced from its neighboring regions at substantially equal distances, there being groups of said regions repeatingly spaced along said continuous medium, each said group comprising regions of yellow, magenta, cyan and black inks, the size of one region in each group being different from the size of at least one other region in said group; and an image forming apparatus responsive to image-forming signals for forming a multi-color image on a sheet, said apparatus comprising holding means for holding said ink ribbon and ink transfer means for forming an image by applying said cyan, magenta and yellow inks, one over the other, to the sheet to form an image in accordance with color signals representing a color image and for transferring black ink in response to a black-color signal.

Claim 20

In combination: an ink ribbon comprising a continuous medium and discrete regions of ink arranged serially along the length of said continuous medium, each region being spaced from its neighboring regions at substantially equal distances, there being groups of said regions repeatingly spaced along said continuous medium, each said group comprising regions of yellow, magenta, cyan and black inks, the size of one region in each group being different from the size of at least one other region in said group; and an image forming apparatus responsive to image-forming signals for forming a multi-color image on a sheet, said apparatus comprising holding means for holding said ink ribbon and ink transfer means for forming an image by applying said cyan, magenta and yellow inks, one over the other, to the sheet to form an image in accordance with color signals representing a color image and for transferring black ink in response to a black-color signal.

Claim 21

The combination of claim 16, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area equal to substantially all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover substantially all of a face of a sheet of said first size of paper; and transferring said black ink to cover substantially all of a face of a sheet of said second size of paper.

Claim 22

The combination of claim 16, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area to substantially all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover an area substantially equal to the difference between the sizes of said first and second sizes.

Claim 23

Apparatus as claimed in claim 2, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area equal to substantialy all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover substantially all of a face of a sheet of said first size of paper; and transferring said black ink to cover substantially all of a face of a sheet of said second size of paper.

Claim 24

Apparatus as claimed in claim 4, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area equal to substantialy all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover an area substantially equal to the difference between the sizes of said first and second sizes.

Claim 25

Apparatus as claimed in claim 7, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area equal to substantialy all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover substantially all of a face of a sheet of said first size of paper; and transferring said black ink to cover substantially all of a face of a sheet of said second size of paper.

Claim 26

Apparatus as claimed in claim 9, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area equal to substantialy all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover an area substantially equal to the difference between the sizes of said first and second sizes.

Claim 27

Apparatus as claimed in claim 12, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area equal to substantialy all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover substantially all of a face of a sheet of said first size of paper; and transferring said black ink to cover substantially all of a face of a sheet of said second size of paper.

Claim 28

Apparatus as claimed in claim 14, wherein said apparatus comprises means for: transferring said yellow, magenta and cyan inks to cover an area equal to substantialy all of a face of a sheet of a smaller, first size of paper; transferring said yellow, magenta and cyan inks to cover the same area of a face of a second, larger size of paper; transferring said black ink to cover an area substantially equal to the difference between the sizes of said first and second sizes.