PROCEDE D'IMPRESSION PAR JET D'ENCRE POUR LA PRODUCTION D'IMAGES

INK JET PRINTING PROCESS FOR THE PRODUCTION OF PICTURES

Abrégé anglais

In an ink jet printing process for the recording of image information onto an
especially sheet
carrier material, the carrier material (B) is held during the printing process
on a support (30)
having drainage means. In this manner one can print without margins, whereby
ink droplets
which fall beside the carrier material are removed through the support so that
the danger of
soilage of the printing mechanism or the subsequent pictures is avoided.

Revendications

Claims:
1. Ink jet printing apparatus for the recording of image information on a
carrier material,
comprising a support for supporting the carrier material during the printing
process, the
support having drainage means for removing ink deposited thereon.
2. Apparatus according to claim 1, wherein the support is a porous film.
3. Apparatus according to claim 1, wherein the support is constructed as one
of a porous
plate and a porous band.
4. Apparatus according to one of claims 1 and 2, characterized in that the
support has an
open celled honeycomb structure and a porous film.
5. Apparatus according to claim 1, wherein the support is provided with
throughgoing
openings.
6. Apparatus according to one of claims 1, 2 and 5, wherein the support is
provided at its
upper surface with a net shaped array of drainage channels.
7. Apparatus according to claim 1, wherein excess ink is drained through the
support, by
sucking it therethrough by a vacuum.
8. Support for the holding of a carrier material to be printed during a
printing process,
wherein the support is porous for draining away excess ink deposited thereon.
9. Process for ink printing, comprising the steps of providing a copy material
for recording
image information, providing a support for supporting the copy material during
printing, the support having a drainage means for draining ink deposited on
the support,
providing an ink jet printing means for depositing ink on the copy material,
operating
the printing means to record the image information on the copy material, and
operating
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the drainage means of the support to drain excess ink deposited on the support
beyond
the copy material.
6

Description

CA 02291925 1999-12-07
INK JET PRINTING PROCESS FOR THE PRODUCTION OF PICTURES
Field of the Invention
The invention relates to an ink jet printing process for the recording of
image information
especially on sheet type carrier material.
Background Art
In the conventional manufacture of photographic prints, the exposure is
typically without
margins, which means the region of exposure is of the same size as or somewhat
larger than
the copy material in sheet form. In the case of band-shaped copy material, the
region of
exposure is accordingly as wide as or somewhat wider than the copy material
band.
In the digital picture manufacture, ink jet printers are often used for the
recording of the image
information on the Garner material. However, one thereby always prints with
margins,
whereby the un-printed margin is possibly later also severed. The reason
herefor is that during
printing up to the edge of the carrier material and especially beyond the
edge, the print
mechanism and the rear face of the flowing prints would be soiled. However ,
when printing
with a margin, the printable surface is not completely used on one hand and
undesired waste
is generated on the other hand.
Summary of the Invention
With the present invention, an ink jet printing process of the generic type
shall now be
improved such that one can print without margin without soiling of printing
mechanism or
the downstream images.
The solution of the object which forms the basis for the invention results
from the features
described in the characterizing portion of the independent claim. Especially
advantageous
embodiments and improvements are the subject of the dependent claims.
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CA 02291925 1999-12-07
According to the principle idea of the invention, the Garner material is
supported during the
printing on a support provided with drainage means. Ink drops which hit the
support outside
the margins of the Garner material are thereby removed through the drainage
means and
therefore can neither soil the printing mechanism nor the downstream pictures.
As can be derived from the figures, the invention concerns an ink jet printing
process for the
recording of image information on a carrier especially in sheet form, wherein
the Garner
material B is supported during the printing process on a support having
drainage means.
According to a first variation the support is porous film, and according to a
further variation,
the support is constructed as a porous plate or a porous band. Additionally,
the support can
have an open celled honeycombed structure and/or a porous film and can be
provided with
passthrough openings. On the other hand, the support can be provided at its
upper surface with
a net shaped array of drainage channels.
Excess ink can be removed through the support, by sucking it there-through.
Brief Description of the Drawings
The invention will be further described in the following by way of the
drawing. It show:
Figure 1 a first embodiment of a support provided with drainage means,
Figure 2 a detailed section through the support of Figure 1,
Figures 3 to 5, three variants of a support provided with drainage means and
Figure 6 a support in the form of an endless band provided with drainage
means.
Detailed Description of the Preferred Embodiment
As is apparent from the full illustration in Figure 1, a sheet B of a carrier
material to be
printed is supported during the printing process on a support 20 which is
constructed as a
porous, air and liquid permeable plate. The drainage means are therefor formed
by the pores
21 in the blade ( Figure 2).
An only symbolically indicated aggregate 11 of ink jet printing heads is
positioned above the
support, which heads are controlled in a conventional manner by a not
illustrated computer.
The support 20 is at its underside connected with a vacuum source 12. By the
vacuum
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CA 02291925 1999-12-07
produced by the vacuum source 12, the sheet B is on the one hand held
steadfast during the
printing process on the one hand and on the other hand the ink droplets 13
(Figure 2) which
impact the support outside the sheet are sucked through the porous plate and
removed
downwardly.
The support 30 shown in Figure 3 is also constructed as a porous plate, has
however at its
upper side an additional mesh shaped arrangement of channels 3, the spacing of
which is
selected such that a fit for the common sheet formats. With this it is
achieved that the sheet
B is respectively directly surrounded by channels. Ink droplets which fall
beside therefor fall
directly into the channels and thereby cannot soil subsequent sheets. The
surplus ink droplets
are again sucked off through the porous plate. The drainage means are here
formed by the
pores of the plate as well as its channels 31.
Figure 4 shows a support 40 which consists of a porous foil 41 and an open
celled honeycomb
structure 42 located thereunder. This embodiment corresponds in its function
to the one of
Figure 1. The drainage means are here formed by the pores in the foil 41 as
well as the open
celled honeycomb structure 42.
The support 50 shown in Figure 5 consists of a nonporous solid material, but
is provided at
its upperside with a network of channels 51 similar to the embodiment of
Figure 3, whereby
pass-through openings 52 are provided in the raised portions between the
channels and if
required also in the channels themselves. The drainage means are thus here
also formed by
the pass-through openings 52 and the channels 51.
Figure 6 finally shows a support in the form of a endless band 60, which is
tightened around
2 rollers 61 and 62. The band 60 consists of an absorbent or porous material
which forms the
drainage means. The excess ink is either stored in the band 60 or, as in the
other
embodiments, sucked through the band 60. Of course, in the former case, the
band 60 must
be cleaned from time to time depending on the degree of soilage. If desired,
the band 60 can
also be used as a transport means for the sheet B.
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CA 02291925 1999-12-07
All aforedescribed embodiments of the support are accordingly also usable with
band-shaped
Garner material.

Dessin représentatif