Printing – Antismut device – Drying with fluid or by heating
Reexamination Certificate
2001-02-12
2004-08-31
Eickholt, Eugene H. (Department: 2854)
Printing
Antismut device
Drying with fluid or by heating
C347S102000
Reexamination Certificate
active
06782822
ABSTRACT:
DESCRIPTION
1. Field of the Invention
The present invention relates to an apparatus and a method for printing images; the invention especially concerns the printer configuration. The invention is particularly suitable for ink-jet printing. The invention is particularly suitable for duplex printing and may also be applied to simplex printing.
2. Background of the Invention
Whereas in simplex printing an image is printed on only a single side of a receiving substrate such as a sheet of paper, in duplex printing images are printed on both sides. When applying liquid ink to the receiving substrate in order to print the image, the wet receiving substrate first has to dry before it can be processed further; e.g. when printing on paper sheets, the printed sheet must be dry before the next sheet can be stacked on top of it.
U.S. Pat. No. 4,469,026 discloses a printer having a sheet fed and drum transport assembly. Ink is applied to a sheet while it is transported by the drum. Subsequently, the receiving substrate is detached from the drum and conveyed by a vacuum belt past a dryer.
U.S. Pat. No. 5,712,672 discloses a printer wherein sheets are transported by means of a vacuum belt past an ink-jet printhead and through a microwave dryer.
Patent application WO 99/11 551 discloses a printer wherein sheets are transported by a vacuum drum. A simplex printer has one vacuum drum, while a duplex printer uses two counter-rotating drums. In a duplex printer, a first image is printed on one side of a paper sheet while the sheet is on the first drum; then the paper is fed to the second drum so that the first printed image contacts the second drum, and a second image is printed on the opposite side of the paper. The printer can also be used to print on a continuous web instead of on separate sheets.
U.S. Pat. No. 4,609,517 discloses a printer having a device for flattening curled sheets subsequent to printing and at least partial drying thereof. The sheets are transported by a belt that has a straight portion along which a print module and a drying module are located.
U.S. Pat. No. 5,623,288 discloses several embodiments of a printer for making enlarged prints on a continuous web of receiving substrate. In a specific embodiment, the receiving substrate is passed around a first drive roller while ink is applied to the first side of the receiving substrate The receiving substrate is then dried along a straight portion of its path. Subsequently, the receiving substrate is passed around a second drive roller while ink is applied to the second side of the receiving substrate, opposite to the first side. Then, the receiving substrate is dried again, along another straight portion of its path.
U.S. Pat. No. 5,966,145 discloses a printer for textile printing on a cloth. A thin endless metallic belt transports the cloth past two printing units and a drying unit in-between that are all located along a straight portion of the belt. The cloth is separated from the belt and dried again by a post-drying unit located at another straight portion of the cloth path.
U.S. Pat. No. 4,566,014 discloses a sheet printer wherein the gap between successive sheets is adjusted for optimal drying of the sheets. The printer has a printing unit that is located along a straight portion of the sheet path. After printing, the sheet is dried in a drying unit along a straight portion of a first belt, a portion of a drum and a straight portion of a second belt. Optionally, the printed sheet may be re-fed to the printing unit and the drying unit for duplex printing.
A disadvantage of the printers described above is that they are not compact. This is especially the case in high speed printing, because at high speed the processing operations in the printer, such as drying the receiving substrate, require quite some space.
OBJECTS OF THE INVENTION
It is an object of the present invention to provide a printing apparatus that has a compact configuration.
It is an object of the present invention to provide a method for producing an image on a receiving substrate by means of a printer, so that the printer is compact.
DEFINITION OF TERMS
A “receiving substrate” may be a separate sheet or it may be a continuous web; it may be made of paper, of polyethylene coated paper, of plastic, of white poly(ethylene terephtalate), of another material as known in the art; it may be a laminate of two or more materials; it may comprise one or more special layers such as an image-receiving layer; it may be transparent or opaque. A receiving substrate has two sides opposite to each other; in simplex printing an image is printed on only a single side, in duplex printing images are printed on both sides.
“Liquid ink” is ink that is in the liquid state of aggregation when it is applied to the receiving substrate. Thus, liquid ink includes e.g. the following types of ink, known in the art: water based ink, oil based ink, solvent based ink, hot melt ink. Whereas the first three types of ink are liquid at room temperature, hot melt ink is solid at room temperature and is applied at a temperature higher than room temperature.
A “touch-dry” receiving substrate is a receiving substrate, or a portion thereof, that is substantially dry so that, after printing, mutual contact of the fresh prints is possible without causing smudges. Usually, after printing, separate sheets are stacked on top of each other, while a continuous web may be wound onto a roll or cut into sheets that are stacked, so that portions of the printed web contact each other.
A “drying section” is a section, or portion, of the apparatus wherein the receiving substrate, still containing wet ink originating from the ink application, is subjected to a drying process so that it becomes touch-dry. The drying process may be different, depending on the type of ink; e.g.:
for water based ink, the drying process involves absorption and penetration of the ink in the receiving substrate and evaporation of water from the ink;
for oil based ink, the drying process involves absorption and penetration;
for solvent based ink, the drying process primarily involves evaporation;
for hot melt ink, the drying process involves solidification of the ink.
The drying process can occur in a ‘passive’ way, or in an ‘active’ way by using drying means in order to accelerate the drying process. For water based ink, for instance, natural air drying is a ‘passive’ way of drying, whereas ‘active’ drying involves using drying means such as infrared lamps, microwave energy applicators, hot air applicators, or other drying means as known in the art; a combination of passive and active drying may also be used.
“Drying means” are discussed in the definition of a “drying section” above.
A “convex curve” along which a printed receiving substrate is transported is a curve that has its centres of curvature ‘CC’ further away from the printed side ‘PR’ of the receiving substrate than from the other side ‘OS’ of the receiving substrate; i.e. along a straight line starting at a centre of curvature CC of the curve and intersecting the receiving substrate, the order wherein the sides are encountered is: CC, OS, PR. The printed side PR of the receiving substrate is that side which was printed last; it may still contain wet ink.
FIG. 1
shows a convex curve
31
(ink is applied last by ink application means
11
) and a concave, i.e. non-convex curve
59
(ink is applied last by ink application means
21
).
FIG. 1
is further discussed below. A convex curve may be a circular curve or a non-circular curve. A circular curve has one centre of curvature, viz. the centre of the circle of which the curve forms a part. For a non-circular curve, each point P of the curve has a corresponding centre of curvature CC which is defined as the limiting position of the point of intersection of the normals at P and at a neighbouring point Q, as Q is made to approach P along the curve (see e.g. “Marks' Standard Handbook for Mechanical Engineers”, Baumeister et. al, ISBN 0-07-004123-7, McGraw-Hill, eighth edition, page 2-45). A “concave curve” along which a print
De Ruyter Dirk
Verhoest Bart
Verlinden Bart
Agfa-Gevaert
Eickholt Eugene H.
Hoffman, Warnick & D'Alessandro LLC
Merecki John A.
LandOfFree
Compact printing apparatus and method does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Compact printing apparatus and method, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Compact printing apparatus and method will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3298084