Incremental printing of symbolic information – Ink jet – Medium and processing means
Reexamination Certificate
2002-09-30
2004-02-24
Meier, Stephen D. (Department: 2853)
Incremental printing of symbolic information
Ink jet
Medium and processing means
C428S032100
Reexamination Certificate
active
06695447
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a porous ink jet recording element.
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 on at least one surface thereof at least one ink-receiving layer. The ink-receiving layer is typically either a porous layer that imbibes the ink via capillary action, or a polymer layer that swells to absorb the ink. Transparent swellable hydrophilic polymer layers do not scatter light and therefore afford optimal image density and gamut, but take an undesirably long time to dry. Porous ink-receiving layers are usually composed of inorganic or organic particles bonded together by a binder. During the ink jet printing process, ink droplets are rapidly absorbed into the coating through capillary action and the image is dry-to-touch right after it comes out of the printer. Therefore, porous coatings allow a fast “drying” of the ink and produce a smear-resistant image. However porous layers, by virtue of the large number of air particle interfaces, scatter light which results in lower densities of printed images.
Elements which comprise two distinct layers have been constructed which have an uppermost porous layer and an underlying swellable polymer layer. Such constructions suffer from poor image quality, as the rate of ink absorption in the upper porous layer via capillary action is orders of magnitude faster than absorption by ink diffusion into the swellable layer. This difference in absorption rates leads to unwanted lateral diffusion of ink at the interface between the layers, a phenomenon termed bleed in the art.
Ink jet prints, prepared by printing onto ink jet recording elements, are subject to environmental degradation. They are especially vulnerable to damage resulting from contact with water and atmospheric gases such as ozone. The damage resulting from the post imaging contact with water can take the form of water spots resulting from deglossing of the top coat, dye smearing due to unwanted dye diffusion, and even gross dissolution of the image recording layer. Ozone bleaches ink jet dyes resulting in loss of density. To overcome these deficiencies, ink jet prints are often laminated. However, lamination is expensive as it requires a separate roll of material.
Efforts have been made to avoid lamination and yet provide protected inkjet prints by providing an inkjet receiver having an uppermost fusible ink-transporting layer and an underlying ink-retaining layer.
U.S. Pat. No. 4,785,313 and U.S. Pat. No. 4,832,984 relate to an ink jet recording element comprising a support having thereon a porous fusible, ink-transporting layer and a swellable polymeric ink-retaining layer, wherein the ink-retaining layer is non-porous. However, there is a problem with this element in that it has poor image quality.
EP 858, 905A1 relates to an ink jet recording element having a porous fusible ink-transporting outermost layer formed by heat sintering thermoplastic particles, and an underlying porous layer to absorb and retain the ink applied to the outermost layer to form an image. The underlying porous ink-retaining layer is constituted mainly of refractory pigments. After imaging, the outermost layer is made non-porous. There are problems with this element in that the ink-retaining layer remains light scattering and therefore fused prints suffer from low density, and the sintered outermost,layer has poor abrasion resistance.
EP 1,188,573 A2 relates to a recording material comprising in order: a sheet-like paper substrate, at least one pigment layer coated thereon, and at least one sealing layer coated thereon. Also disclosed is an optional dye trapping layer present between the pigment layer and the sealing layer. There are several problems with this element in that the binder in the sealing layer is water-soluble which degrades the water resistance of sealed prints. While the sealing layer is porous, the dye trapping layer is not which leads to bleed and degraded image quality.
It is an object of this invention to provide an inkjet recording element which can be printed with ink jet inks and fused to provide high density images. It is another object of the invention to provide a porous ink-transporting layer that has good mechanical integrity and is abrasion resistant. It is another object of the invention to provide a protective uppermost ink-transporting layer that is thermally fusible and thereby can be rendered water resistant. It is another object to provide an inkjet recording element that has a fusible dye-trapping layer which captures and retains inkjet dyes, and which can be subsequently fused to remove light scatter and provide optimal image density.
SUMMARY OF THE INVENTION
These and other objects are achieved in accordance with the invention which comprises an ink jet recording element comprising a support having thereon in order:
a) at least one porous, ink carrier liquid receptive layer;
b) a fusible, porous dye-trapping layer comprising fusible polymeric particles, a binder, and a dye mordant; and
c) a fusible, porous ink-transporting layer comprising fusible, polymeric particles and a film-forming, hydrophobic binder.
By use of the invention, a porous ink jet recording element is obtained that has good abrasion resistance, and which when printed with an ink jet ink, and subsequently fused, has good water-resistance and high print density.
DETAILED DESCRIPTION OF THE INVENTION
The uppermost porous ink-transporting layer allows for passage of the ink to the underlying layers, but is non-retentive of the dye colorant.
The fusible, polymeric particles employed in the uppermost ink-transporting layer of the invention may have any particle size provided they will form a porous layer. In a preferred embodiment of the invention, the particle size of the fusible, polymeric particle may range from about 0.5 to about 10 &mgr;m.
Upon fusing of the polymeric particles, the air particle interfaces present in the original porous structure of the layer are eliminated and a non-scattering, substantially continuous, protective overcoat forms over the image. The fusible, polymeric particles may be formed from a condensation polymer, a styrenic polymer, a vinyl polymer, an ethylene-vinyl chloride copolymer, a polyacrylate, poly(vinyl acetate), poly(vinylidene chloride), or a vinyl acetate-vinyl chloride copolymer. In a preferred embodiment of the invention, the fusible, polymeric particles are comprised of a cellulose acetate ester, a polyester or a polyurethane. Most preferred is a cellulose acetate butyrate.
The uppermost porous ink-transporting layer of fusible polymeric particles will additionally contain a film-forming hydrophobic binder. The film-forming, hydrophobic binder useful in the invention can be any film-forming hydrophobic polymer capable of being dispersed in water. In a preferred embodiment of the invention, the hydrophobic binder is an aqueous dispersion of an acrylic polymer or a polyurethane.
In order to be non-retentive of dyes, the polymers comprising the fusible particles and the hydrophobic binder should either be non-ionic or of the same charge type as the dye. Since ink jet dyes are anionic in a preferred embodiment, both the fusible polymeric particles and the hydrophobic film-forming binder are either nonionic or anionic. Accordingly, in a most preferred embodiment, the polymers comprising the fusible particles and the film-forming hydrophobic binder shall either have no ionic functionality or anionic functionality.
The particle-to-binder ratio of the particles and binder employed in the ink-transporting layer can rang
Cole Harold E.
Eastman Kodak Company
Konkol Chris P
Meier Stephen D.
Shah Manish
LandOfFree
Ink jet recording element 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 recording element, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ink jet recording element will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3354618