Stock material or miscellaneous articles – Structurally defined web or sheet – Discontinuous or differential coating – impregnation or bond
Reexamination Certificate
2000-02-11
2003-03-04
Jones, Deborah (Department: 1775)
Stock material or miscellaneous articles
Structurally defined web or sheet
Discontinuous or differential coating, impregnation or bond
C428S207000, C428S216000, C428S331000, C428S327000, C428S341000, C428S500000, C428S537500, C428S704000, C347S101000, C347S105000, C427S256000
Reexamination Certificate
active
06528146
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a recording medium having an ink-receiving layer formed on the base member. The present invention relates also to a method of image formation employing the recording medium.
2. Related Background Art
Recording mediums of various constructions are known for image formation by ink-jet recording. The recording mediums are required to have better performance in various respects as the fields of application expand into output of electronic image information by an ink-jet printer from computers and networks and output of image information from digital cameras, digital video devices, scanners, or the like, and as various functions become more advanced.
For example, Japanese Patent Application Laid-Open No. 9-175010 discloses a construction of a recording medium for improving the ink absorption and ink fixation, in which the ink-receiving layer containing silica and a binder resin provided on a supporting member has a two-layer structure, the first ink-receiving layer on the supporting member side containing silica particles of an average particle diameter of 1.0 to 6.0 &mgr;m, and the second ink-receiving layer outside containing silica particles of an average particle diameter of 7.0 to 25.0 &mgr;m; the average particle diameter of the silica particles in the first ink-receiving layer being smaller than that in the second ink-receiving layer. Japanese Patent Application Laid-Open Nos. 10-120976 and 10-193780 respectively disclose an ink-receiving layer, for improving ink-fixation and water-resistance, which has a lamination structure comprising a transparent lower layer composed of a graft polymer resin and a transparent upper layer composed of a copolymer containing a cationic quaternary ammonium base. Japanese Patent Application Laid-Open No. 8-230311 discloses a constitution having an ink-receiving layer containing a cationic surfactant and a cationic polymer. Japanese Patent Application Laid-Open No. 8-310115 discloses an ink-receiving layer constituted of a layer of alumina hydrate agglomerated by an anion.
On the other hand, the ink-jet recording method, if it is capable of giving an image quality comparable to that of silver-salt color photograph or that of multicolor printing, can reduce remarkably the unit cost of image formation. Such techniques are demanded to an increasing extent.
For formation of a multicolor image comparable to that of silver salt photograph or multicolor printing, in a known method, the ink-jet recording is conducted on a recording medium having an ink-receiving layer containing porous white fine particles like silica on a base member and after image formation by ink-jet recording a transparent film layer is formed on the ink-receiving layer to raise the surface gloss or surface smoothness of the image to improve the image quality.
In order to form an image of a high quality, comparable to that of silver salt photograph or multicolor printing, by ink-jet printing and formation of a transparent film layer on the ink-receiving layer to give smoothness and gloss to the printed image surface, a larger amount of ink should be received by the ink-receiving layer at the portion of higher image density or higher gradation. Therefore, the recording medium for such uses should have higher ink absorbency.
The higher ink-absorbency for such purpose can be achieved by various methods such as increase of the layer thickness of the ink-receiving layer, or increase of the porosity of the ink-receiving layer by selecting the properties or amount of addition of the fine porous particles or the composition of the ink-receiving layer.
In the method of formation of a transparent film layer on the ink-receiving layer, the gloss and the smoothness of the surface of the ink-receiving layer itself are not necessary for the gloss and the smoothness of the image, since the necessary gloss and smoothness are given by the transparent film layer. Therefore, this degree of freedom is higher in designing the ink-receiving layer to increase the ink-receiving capacity than that for a recording medium having no transparent film layer. For example, the thickness of the ink-receiving layer may be increased, or the size of porous fine particles used may be larger.
However, it was found by the inventors of the present invention that, when the ink-receiving capacity of the ink-receiving layer is increased by increasing the thickness of the ink receiving layer containing the porous fine particles like silica or by increasing the porosity of the ink receiving layer by selection of the porous fine particles, the coloring matter is liable to diffuse into the interior of the ink-receiving layer upon deposition of the ink onto the ink-receiving layer. This sometimes impairs the color development or the image density. Further, it was found by the inventors of the present invention that, in this type of recording medium, the coloring matter in the ink diffuses or spreads in the ink-receiving layer to cause color spreading or color tone change with lapse of time, which is significant when a transparent film layer is formed on the ink-receiving layer after image formation. The aforementioned diffusion or spreading of the coloring matter does not necessarily cause disadvantages, depending on the quality required for the image, but is a problem to be solved in obtaining a higher quality image.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a recording medium which is coated after image formation with a transparent film layer without impairing the properties of the ink-receiving layer and with improvement of color development and coloring matter fixation.
Another object of the present invention is to provide a method of image formation employing the above recording medium.
The recording medium of the present invention has a base member and an ink-receiving layer containing amorphous silica provided on the base member, wherein the ink-receiving layer comprises a lower layer and an upper layer formed successively in lamination on the base member, the upper layer containing a cationic group, and the lower layer containing an anionic group.
The method of image formation of the present invention comprises forming an image by depositing an ink onto an ink-receiving layer of the recording medium and subsequently forming a transparent film layer on the face of the ink-receiving layer to prepare a printed matter having an image face protected by the transparent film on the ink-receiving layer, wherein the recording medium has the constitution defined above.
With the recording medium and the image forming method of the present invention, the coloring matter in the ink is retained so as not to diffuse or spread in the ink-receiving layer, thus restricting the range of coloring matter fixation to be within the ink-receiving layer surface, thereby improving the color development and color fixation, and causing no color change with lapse of time.
REFERENCES:
patent: 5576088 (1996-11-01), Ogawa et al.
patent: 5804320 (1998-09-01), Tomioka et al.
patent: 8-230311 (1996-09-01), None
patent: 8-310115 (1996-11-01), None
patent: 9-175010 (1997-07-01), None
patent: 10-120976 (1998-05-01), None
patent: 10-193780 (1998-07-01), None
Miyasaka Mitsuo
Nagata Toru
Ochiai Hiroshi
Okuda Teruaki
Riku Shuichiro
Jones Deborah
Xu Ling
LandOfFree
Recording medium and image formation employing the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Recording medium and image formation employing the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Recording medium and image formation employing the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3075413