Incremental printing of symbolic information – Ink jet – Medium and processing means
Reexamination Certificate
2000-05-26
2002-08-06
Hess, Bruce H. (Department: 1774)
Incremental printing of symbolic information
Ink jet
Medium and processing means
C428S195100, C428S323000
Reexamination Certificate
active
06428164
ABSTRACT:
Reference is made to commonly-assigned, copending U.S. Patent Applications:
Ser. No. 09/579,591, filed of even date herewith, of Missell et al., entitled “Ink Jet Printing Process”;
Ser. No. 09/579,635, filed of even date herewith, of Missell et al., entitled “Ink Jet Recording Element”; and
Ser. No. 09/580,184, filed of even date herewith, of Missell et al., entitled “Ink Jet Recording Element”;
the teachings of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates to an ink jet printing method which uses an ink jet recording element which contains certain cellulosic fibers.
BACKGROUND OF THE INVENTION
In a typical ink jet recording or printing system, ink droplets are ejected from a nozzle at high speed towards a recording element or medium to produce an image on the medium. The ink droplets, or recording liquid, generally comprise a recording agent, such as a dye or pigment, and a large amount of solvent. The solvent, or carrier liquid, typically is made up of water, an organic material such as a monohydric alcohol, a polyhydric alcohol or mixtures thereof.
An ink jet recording element typically comprises a support having thereon a base layer for absorbing fluid and an ink-receiving or image-forming layer. The recording element may be porous or non-porous.
Many porous ink jet receivers consist of organic or inorganic particles that form pores by the spacing between the particles, The ink and solvents are pulled into this structure by capillary forces. In order to have enough pore volume or capacity to absorb heavy ink lay downs, these coatings are usually coated to a dry thickness on the order of 40 &mgr;m to 60 &mgr;m, which can be costly because of the layer thickness.
To form a porous ink receiving layer, a binder is added to hold the particles together. However, to maintain a high pore volume, the amount of binder should be as low as possible. Too much binder would start to fill the pores between the particles or beads, which will reduce ink absorption. Too little binder will reduce the integrity of the coating causing cracking.
U.S. Pat. Nos. 5,522,968 and 5,635,297 relate to ink jet receiver elements comprising a support containing cellulose or wood pulp. There is a problem with these elements, however, in that ink jet inks printed on them would tend to bleed through the paper causing paper cockle and low optical density. It is an object of this invention to provide an ink jet printing method which uses an ink jet receiver element which has fast dry times, no paper cockle, high optical density and a lower tendency to crack.
SUMMARY OF THE INVENTION
This and other objects are provided by the present invention comprising an ink jet printing method, comprising the steps of:
A) providing an ink jet printer that is responsive to digital data signals;
B) loading the printer with an ink jet recording element comprising a resin-coated paper support having thereon an ink-retaining layer comprising voided cellulosic fibers and organic or inorganic particles in a polymeric binder, the length of the voided cellulosic fibers being from about 10 &mgr;m to about 50 &mgr;m, the ratio of the voided cellulosic fibers to the organic or inorganic particles being from about 90:10 to about 60:40 and the ratio of the combination of voided cellulosic fibers and the organic or inorganic particles to the polymeric binder being from about 90:10 to about 50:50;
C) loading the printer with an ink jet ink composition; and
D) printing on the ink jet recording element using the ink jet ink in response to the digital data signals.
Using the method of the invention, an ink jet receiver element is obtained which has less cracking than prior art elements.
DETAILED DESCRIPTION OF THE INVENTION
The voided cellulosic fibers used in the ink-retaining layer of the ink jet recording element employed in the process of the invention have greatly increased porosity over organic or inorganic particles usually used in porous layers of many ink jet recording elements. In addition, these voided cellulosic fibers have an internal voided structure that allows them to act as “micro-straws” to further assist in absorbing fluids. This voided cellulosic fiber structure provides very fast dry times with very heavy ink lay volumes. In addition, the images obtained using the voided cellulosic fiber layer also have high optical density.
Examples of voided cellulosic fibers which can be used in the invention include Arbocel® alpha cellulose fibers, manufactured by Rettenmaier of Germany. These cellulosic fibers are made of different woods such as beech, maple or pine, preferably beech. The fibers also vary in length from about 10 &mgr;m to about 50 &mgr;m, with the preferred length of less than about 30 &mgr;m. The width of the fibers is about 18 &mgr;m.
Any polymeric binder may be used in the ink-retaining layer of the ink jet recording element employed in the process of the invention. In general, good results have been obtained with gelatin, a polyurethane, a vinyl acetate-ethylene copolymer, an ethylene-vinyl chloride copolymer, a vinyl acetate-vinyl chloride-ethylene terpolymer, all acrylic polymer or a polyvinyl alcohol.
The organic or inorganic particles used in the ink-retaining layer may be, for example, alumina particles, silica particles or polymer beads, such as methyl methacrylate or styrene.
Any resin-coated paper support may be used in the process of the invention, such as, for example, Kodak photo grade Edge Paper®, Kodak Royal® Paper and Kodak D'Lite® Paper.
If desired, in order to improve the adhesion of the fiber layer to the support, the surface of the support may be corona discharge-treated prior to coating.
The layers described above may be coated by conventional coating means onto a support material commonly used in this art. Coating methods may include, but are not limited to, wound wire rod coating, slot coating, slide hopper coating, gravure, curtain coating and the like.
Ink jet inks used to image the recording elements employed in the process of the present invention are well-known in the art. The ink compositions used in ink jet printing typically are liquid compositions comprising a solvent or carrier liquid, dyes or pigments, humectants, organic solvents, detergents, is thickeners, preservatives, and the like. The solvent or carrier liquid can be solely water or can be water mixed with other water-miscible solvents such as polyhydric alcohols. Inks in which organic materials such as polyhydric alcohols are the predominant carrier or solvent liquid may also be used. Particularly useful are mixed solvents of water and polyhydric alcohols. The dyes used in such compositions are typically water-soluble direct or acid type dyes. Such liquid compositions have been described extensively in the prior art including, for example, U.S. Pat. Nos. 4,381,946; 4,239,543 and 4,781,758, the disclosures of which are hereby incorporated by reference.
The following example further illustrates the invention.
REFERENCES:
patent: 5522968 (1996-06-01), Kuroyama et al.
patent: 5605750 (1997-02-01), Romano et al.
patent: 5635297 (1997-06-01), Ogawa et al.
Missell Gregory E.
Suminski Christine
Cole Harold E.
Eastman Kodak Company
Grendzynski Michael
Hess Bruce H.
LandOfFree
Ink jet printing process does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Ink jet printing process, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink jet printing process will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2920149