Method of dot printing and corresponding ink jet print head
AssigneeOlivetti-Cannon Industriale S.p.A.
InventorsAlcide Clemente, Alessandro Scardovi
Life of this patent
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Abstract
A method of color printing with an ink jet printing head adapted to print one strip for each color and comprising nozzles disposed in distinct groups (22) for each color, with a different number of nozzles from group to group. Each group is separated from the subsequent group by intervals (DCM, DMY) of different magnitude. The method consists of printing strips of a subsequent color only after having printed at least two strips of a first color and superimposing each subsequent color on the first of the two strips printed previously.
Claims23
A method of printing an image on a printing medium with an ink jet printing head reciprocatable along a scanning direction substantially orthogonal to a feed direction of the printing medium in order to perform a sequence of passes, said head having groups of nozzles for printing strips with ink of correspondingly different colours on said printing medium during said passes, said different colours comprising a first colour and at least one subsequent colour, the method comprising the steps of:
- printing a first strip of said first colour during a first pass of the head across the printing medium;
- printing a second strip of said first colour adjacent to said first strip during a second pass of the head across the printing medium;
- printing a third strip of said first colour adjacent to said second strip during a third pass of the head across the printing medium and simultaneously printing a first strip of said at least one subsequent colour on said first strip of said first colour, said first strip of said at least one subsequent color having a greater width than a width of said first strip of said first color and overflowing on to said second strip of said first colour by a predetermined quantity (H), whereby shades of colour are formed in a substantially regular manner over said printing medium.
A method of colour printing with an ink jet printing head including separate groups of nozzles, in which each group of said groups of nozzles prints a strip of a different colour on a printing medium advanced intermittently in a feed direction by an interlinear spacing of predetermined magnitude, comprising the following steps:
- a) printing a first strip of a first colour;
- b) printing a second strip of said first colour adjacent to said first strip of said first colour;
- c) printing a third strip of said first colour adjacent to said second strip of said first color and a first strip of a second colour totally superimposed upon said first strip of said first colour and overflowing on to said second strip of said first colour by a first quantity (H);
- d) printing a fourth strip of said first colour adjacent to said third strip of said first color and a second strip of said second colour adjacent to said first strip of said second colour, superimposed upon said second strip of said first colour and overflowing on to said third strip of said first colour by said first quantity (H);
- e) printing a fifth strip of said first colour adjacent to said fourth strip of of said first colour, a third strip of said second colour adjacent to said second strip of said second colour and superimposed upon said third strip of said first colour and overflowing on to said adjacent fourth strip of said first colour by said first quantity (H), and a strip of a third colour totally superimposed upon said first strip of said second colour and overflowing on to said second adjacent strip of said second colour by a second quantity (K).
An ink jet dot printing head for printing data on a printing medium advanced intermittently in a feed direction by an interlinear spacing of predetermined magnitude, said head comprising a plurality of nozzles for ink emission, said nozzles being spaced in said feed direction by a pitch of constant magnitude, and disposed in groups arranged in colunms aligned along a common axis substantially parallel to said feed direction, wherein said groups are arranged at intervals of different magnitude from one another, and each of said groups comprises a different number of nozzles from one another.
Dependencies are inferred from the claim text.