Abstract

Provided is a thermosensitive grain-free printing plate. The thermosensitive grain-free printing plate consists of a support, a hydrophilic layer and a thermosensitive layer, with the hydrophilic layer and the thermosensitive layer being successively coated on the support. The presence of hydrophilic particles in nano scale and/or micron scale in the hydrophilic layer ensures that the hydrophilic layer has an appropriate roughness, which does not only meet the requirements of ink absorption but also improves the abrasive resistance of the surface of the plate base. Moreover, both the cohesive forces between the hydrophilic layer and the support and between the hydrophilic layer and the thermosensitive layer are good. This grain-free printing plate avoids the contamination caused by waste acid and waste base liquids produced by electrolysis and oxidation of aluminium plates in the existing thermosensitive plates.

IPC Classes  ?

• B41N 1/14 - Lithographic printing foils
• B41N 1/08 - Printing plates or foilsMaterials therefor metallic for lithographic printing
• G03F 7/004 - Photosensitive materials
• C09D 7/12 - Other additives

Abstract

A photosensitive grain-free printing plate, consisting of a plate base, a hydrophilic layer and a photosensitive layer, with the hydrophilic layer and the photosensitive layer being successively coated on the plate base. A hydrophilic coating is obtained by coating a composition of nano-scale and/or micron-scale particles or a composition containing nano-scale and/or micron-scale particles on the surface of the plate base. The hydrophilic coating thus obtained has an appropriate roughness, which imparts to the surface of the plate base hydrophilic and water-retaining properties. The presence of hydrophilic particles in nano scale and/or micron scale in the hydrophilic layer does not only ensure that the printing plate meets the requirements of ink absorption but also improves the abrasive resistance of the plate base surface, and furthermore maintains good cohesive forces between the hydrophilic layer and the printing base and between the hydrophilic layer and the photosensitive layer. In comparison with the existing photosensitive plates, the contamination caused by the waste acid and waste base liquids produced by electrolysis and oxidation of aluminium plates is avoided and the water and electricity consumption is reduced.

IPC Classes  ?

• B41N 1/08 - Printing plates or foilsMaterials therefor metallic for lithographic printing
• B41N 3/04 - Graining or abrasion by mechanical means
• B41C 1/10 - Forme preparation for lithographic printingMaster sheets for transferring a lithographic image to the forme

Abstract

A platemaking method is disclosed, which includes the following steps: screening inputted image-text information of the page to convert continuous tone image-text information to halftone image-text information; generating dot-matrix information of unit dots, which includes plurality of unit dot information consisting of the position and the size of every unit dot, wherein the position and the size of every unit dot correspond to the central position and the size of a screened dot of halftone image-text information respectively, the position of every unit dot indicates correspondingly an order position of an output dot, and the size value of each unit dot is two or more values each of which indicates correspondingly a physical dimension grade of an output dot; outputting the output dot at a corresponding actual position on a film or other printing plate according to the dot-matrix information of unit dots generated in the above step, wherein after reading the position and the size of every unit dot in the dot-matrix information of unit dots, outputting the output dot whose physical dimension corresponds to that indicated by the size of an unit dot at a corresponding order position on a film or other printing plate. The method greatly reduces the memory space required by screening and improves the output quality of platemaking. A platemaking device is also disclosed.

IPC Classes  ?

• H04N 1/405 - Halftoning, i.e. converting the picture signal of a continuous-tone original into a corresponding signal showing only two levels
• G06F 3/12 - Digital output to print unit
• G06F 3/13 - Digital output to plotter
• B41J 3/407 - Typewriters or selective printing or marking mechanisms characterised by the purpose for which they are constructed for marking on special material
• B41C 1/00 - Forme preparation
• B41M 1/26 - Printing on other surfaces than ordinary paper
• G03F 5/00 - Screening processesScreens therefor

Abstract

A monochrome inkjet printing device, a method thereof and a method for converting a color inkjet printing device into a monochrome inkjet printing device are provided. The monochrome inkjet printing device comprises a printing mechanism including a printhead assembly for ejecting ink and ink cartridges for storing monochrome ink, a carriage mechanism including a carriage assembly for mounting the printhead assembly and the ink cartridges, and a control device for controlling the printing of the printhead assembly. The printhead assembly has a nozzle group in the form of n*m arrays (n>1,m>1). During printing, the carriage assembly is driven to scan back and forth in the transverse direction of a print media and print in every scan zone simultaneously. After a single scan, the print media is moved relative to the carriage assembly so that a predefined longitudinal distance between them is shifted incrementally. Then the carriage asembly is driven to scan back and forth in the transverse direction again. The process is repeated until all the transverse scan zones have been scanned the predefined times set by the requirement of precision. The control device controls every array of nozzles to run during every transverse scan, and ink drops ejected from every nozzle to be located at different positions on the print media.

IPC Classes  ?

• B41J 2/14 - Structure thereof
• B41J 29/38 - Drives, motors, controls, or automatic cut-off devices for the entire printing mechanism

Abstract

A large- format inkjet printing apparatus includes multiple printing head units (11, 12, 13, 14). Each of the printing head units can intermittently and steppingly move in a first direction (Y) and has an inject print head which can move reciprocatingly in a second direction (X) perpendicular to the first direction within an interval between two steps and print sub-images (21, 22, 23, 24). Before printing starts, the printing head units are disposed at one end of a print medium, and arranged to seamlessly splice the sub-images printed by the printing head units into a complete large- format image.

IPC Classes  ?

• B41J 3/42 - Two or more complete typewriters coupled for simultaneous operation