Support for imaging material

Details Support for imaging material Support for imaging material

1998-02-22

2002-01-01

Copenheaver, Blaine (Department: 1773)

Stock material or miscellaneous articles

Composite

Of addition polymer from unsaturated monomers

C428S535000, C430S438000, C162S125000, C162S130000, C162S141000

Reexamination Certificate

active

06335102

ABSTRACT:

BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a support for an imaging material, more specifically to a support whose surface on one side of a paper substrate composed mainly of a natural pulp where an image-forming layer is to be formed is coated with a resin sheet, which support not only can provide an imaging material and a print thereon having a high visual gloss and being free of non-uniformity in gloss, particularly silver halide photographic paper and a print thereon (silver halide photographic paper print will be sometimes abbreviated as “photographic print” hereinafter), but also is improved in the property of peeling from a cooling roll used when the support is produced so that no non-uniformity in peeling occurs, and further, which support has excellent curl resistance and an excellent stiffness and can be stably produced at a high speed.
2. Explanation of Related Art
Generally, an imaging material is constituted of a support for the imaging material and an image-forming layer provided on the support. For example, a silver halide photographic material, an inkjet recording material, a thermal diffusion transfer type heat transfer record receiving material, a heat-sensitive recording material or a photosensitive-thermosensitive recording material is produced by forming an image-forming layer such as a silver halide photograph constituting layer, an ink receiving layer, a thermal transfer type heat transfer record receiving layer, a heat-sensitive color-forming layer or a photosensitive-thermosensitive color-forming layer on a support for an imaging material, respectively, and optionally forming an undercoat layer, a protective layer, and the like. In particular, a silver halide photograph constituting layer is constituted of a silver halide photograph emulsion layer, a protective layer, an undercoat layer, either an intermediate layer or a color mixing prevention layer, either a halation prevention layer or a filter layer and an ultraviolet absorbent layer, or a combination of some of these. For example, a simple silver halide photographic material is structured by forming a silver halide emulsion layer and its protective layer on a support for a photographic material. Further, a multi-layered silver halide color photographic material is structured by consecutively forming silver halide color photograph constituting layers such as an under coat layer, a blue-sensitive silver halide emulsion layer and an intermediate layer, a green-sensitive silver halide emulsion layer and an ultraviolet absorbent layer, and a speed-sensitive silver halide emulsion layer and a protective layer, and the like on a support for a photographic material.
There is conventionally well known a resin-coated paper support in which the surface of a base paper for a support for an imaging material is coated with a resin having film formability. Concerning a support for a photographic material for use in a silver halide photographic material, for example, there is known a support for a photographic material in which a base paper is coated with a resin having film formability, preferably a polyolefin resin. There is also known a support for a photographic material in which both surfaces of a base paper are coated with a polyolefin resin. Further, after the application of the rapid photographic development treatment method of a silver halide photographic material, a support for a photographic material in which the both surfaces of a base paper are coated with a polyethylene resin is mainly practically used as a photographic paper, and the resin layer on one side where an image-forming layer is formed generally contains a titanium dioxide pigment for imparting sharpness as required.
Further, there is known a thermal transfer record receiving element having, as a support, a resin-coated paper of which the resin coating has a surface roughness of 7.5 microinches-AA or less, particularly, a polyethylene-resin-coated paper of which the base paper is surface-coated with a polyethylene resin. There is also known an inkjet recording sheet having a resin-coated paper as a support.
However, a resin-coated paper type support for an imaging material, i.e., a support which is formed of a base paper, particularly a base paper composed mainly of a natural pulp, and which is surface-coated with a resin layer on a surface side where an image-forming layer is to be formed, still has several serious problems, and actually, no satisfactory achievement has been obtained.
First, in a resin-coated paper for use as a support for an imaging material, a base paper is coated with a resin having at least film formability, particularly a resin layer containing a polyethylene-based resin, on a surface side where an image-forming layer is to be formed (a surface on which an image-forming layer is to be formed will be sometimes abbreviated as a front surface, a resin layer coating on the front surface will be sometimes abbreviated as a front resin layer, a side opposite thereto will be sometimes abbreviated as a reverse side, and a resin layer formed on the reverse surface will be sometimes abbreviated as a reverse resin layer). The above resin-coated paper is obtained by a series of steps of casting onto a running base paper a film of polyethylene resin composition extruded through a slit die of a melting extruder; pressing them in a nip of a pressing roll and a cooling roll to bond them; cooling the resultant laminate; and then peeling it from the roll. In this case, for producing a resin-coated paper for an imaging material for glossy use, there is used a cooling roll which has a mirror surface, a gloss surface or a finely roughened surface and has an excellent smoothness. In this manner, the front resin layer in a molten state is brought into contact with the cooling roll having an excellent smoothness under pressure. Therefore, the front resin layer could be processed so as to have a surface having an excellent smoothness, and an imaging material using the above resin-coated paper as a support and a print thereon could have a visually high gloss. However, concerning an imaging material using an actually produced resin-coated paper as a support and a print thereon, it has not been possible to obtain any product having a high-gloss appearance. Concerning a photographic paper using a resin-coated paper in particular, it has not been possible to obtain a photographic paper and a print thereon having a sufficiently high-gloss appearance.
The present inventors have therefore made studies for factors of the high-gloss appearance of imaging materials and their prints. As a result, the gloss appearance is affected by various factors such as a resin-coated paper as a support, an image-forming layer and an image-forming method such as development, while it has been found that the gloss appearance is also greatly affected by the factor of a resin-coated paper as a support. The present inventors have therefore made studies on the factor of a resin-coated paper which affects the appearance of gloss. As a result, it has been found that the gloss appearance not only depends upon the factor of a resin layer but also depends upon a variety of factors including factors of the kind and properties of a base paper composed mainly of a natural pulp such as the kind of a natural pulp and a fiber length, conditions of a paper material slurry such as additives for paper, contained in a paper material slurry, paper-making conditions such as a paper-making speed, a bulk density increasing press conditions and machine calender conditions, post-treatment conditions such as size press and tub size press, and further, the surface roughness of a base paper. It has been also found that as the thickness of a front resin layer of a resin-coated paper decreases, the gloss appearance of an imaging material using the above resin-coated paper as a support and a print thereon decreases, and that when the above thickness is 31 &mgr;m or less, the above gloss appearance greatly decreases. A photographic material for glossy use

Affiliated with

Also associated with

Rating

Support for imaging material does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Support for imaging material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Support for imaging material will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2866312