Fuji Photo Film Company, Limited

Fujifilm Corporation

Takeshi Serikawa

Ikuo Kawauchi

Ippei Nakamura

Koichi Kawamura

Keiji Akiyama

Akio Oda

Tomoyoshi Mitsumoto

Hideo Miyake

Mitsumasa Tsuchiya

Akira Nagashima

Noriaki Watanabe

Kazuo Fujita

Tadashi Endo

A positive planographic printing plate precursor includes a support having disposed thereon a lower thermosensitive layer containing a water-insoluble but alkali-soluble polymer compound and an upper thermosensitive layer containing a water-insoluble but alkali-soluble polymer compound, with alkali-solubility increasing under heat, wherein (i) both the upper thermosensitive layer and the lower thermosensitive layer contain an IR absorbing dye, with the ratio of the IR absorbing dye concentration in the upper thermosensitive layer to the IR absorbing dye concentration in the lower thermosensitive layer is 1.6 to 10.0, and/or (ii) the upper thermosensitive layer and the lower thermosensitive layer contain different IR absorbing dyes, and/or (iii) at least one of the upper thermosensitive layer and the lower thermosensitive layer contains an IR absorbent having, in one molecule, at least two chromophoric groups that absorb IR light, with the chromophoric groups bonding to each other via a covalent bond.

Planographic printing plate precursor

Planorgraphic printing plate precursor

A presensitized plate having: on an aluminum support, a thermosensitive layer containing a photothermal conversion agent which absorbs infrared rays and generates heat and a water-insoluble and alkali-soluble resin, of which solubility to an alkali aqueous solution increases by heating, wherein the aluminum support has a grained structure with large undulation and a grained structure with small undulation on a surface thereof. This presensitized plate is excellent in damage resistance and sensitivity, and after the plate is processed into a lithographic plate, it is also excellent in scum resistance and press life.

Presensitized plate

The invention provides a photosensitive composition including (A) a vinyl polymer containing a copolymerization component having a carboxyl group, having a content of the carboxyl group in a molecule of 2.0 meq/g or higher and having a solubility parameter less than 21.3 MPa, (B) a polymer compound including a phenolic hydroxyl group, and (C) an IR absorber.

Photosensitive composition

An infrared-sensitive photosensitive composition comprising (A) an alkali-soluble resin containing a repeating unit having an alkylene oxide group, and (B) a light-to-heat converting agent; and

Infrared-sensitive photosensitive composition

An infrared-sensitive photosensitive composition comprising:

A photosensitive resin composition containing a high molecular compound having at least a) a fluoro aliphatic group, and b) a group represented by formula &mdash;L&mdash;P (wherein L represents a divalent organic group connected to the skeleton of the high molecular compound, and P represents an aromatic group having a carboxyl group at the ortho-position).

Growing community of inventors

Shizuoka-ken, Japan

Takeshi Serikawa