Tokyo Ohka Kogyo Co., Ltd.

Ciba-Geigy Corporation

Tokyo Ohka Kogyo, K.k.

Katsuyuki Ohta

Toshimi Aoyama

Hiroshi Komano

Toshiya Takagi

Kiyoshi Uchikawa

Takeshi Iwai

Takashi Fujimoto

Naoya Katsumata

Syunzi Nakazato

Norio Seki

The invention discloses a multilayered photosensitive material for processing into a flexographic printing plate by direct patterning with an infrared laser beam. The multilayered material comprises: (A) a substrate; (B) a photosensitive resinous layer having sensitivity to light excepting infrared light and comprising (b1) an elastomeric binder resin, (b2) a polymerizable monomeric compound and (b3) a polymerization initiator formed on the substrate (A); (C) a barrier layer of a composition comprising a resin such as a polyvinyl pyrrolidone and alkali-soluble cellulose compounds, which transmits light other than infrared light and is removable in the development treatment, formed on the photosensitive resinous layer (B); and (D) a masking layer of a composition comprising (d1) a film-forming binder resin, (d2) an infrared absorbing compound and (d3) a compound having no transmissivity to lights other than infrared light and removable by irradiation with an infrared laser beam, formed on the barrier layer (C).

Multilayered photosensitive material for flexographic printing plate

A photosensitive resin composition comprising a polymeric binder, an ethylenically unsaturated monomer and a photopolymerization initiator is disclosed. Also, a PS plate using the same is disclosed. The photopolymerization initiator comprises at least one compound selected from specific triazine compounds having a bromine atom on the substituted phenyl nucleus thereof and specific trihalomethyl-containing triazine compounds. The composition has high photosensitivity sufficient for exposure with an argon laser light and satisfactory developability. Additionally disclosed is a photosensitive resin composition comprising a polymeric binder, a monomer having an ethylenically unsaturated double bond and photopolymerization initiators including an acridine compound and a specific triazine compound. This second photosensitive resin composition has high sensitivity, high resolution and a wide development margin. Using this photosensitive resin composition, color filters and PS plates can be produced that have high sensitivity and resolution even to low-energy visible light and which assure high pattern reproducibility.

Photosensitive resin composition containing a triazine compound and a

Compositions comprising a linear base polymer, an ethylenically unsaturated addition-polymerizable compound and a combination of (A) a 1-benzoyl-1-amino-substituted-1-benzylalkane with (B) an .alpha.-phenyl-.alpha.,.alpha.-dialkoxyacetophenone as photopolymerization initiator are suitable for the production of thick-film printing plates.

Process for the production of printing plates

Photopolymerizable compositions

Disclosed is a photosensitive resin composition for use in a light-shielding film, comprising a photosensitive resin and a light-shielding coloring material, wherein light transmission properties after formation of the light-shielding film are controlled by the light-shielding coloring material so that (i) the light transmission through the light-shielding film is 1% or more in at least one wavelength of a light wavelength region of from 330 nm to less than 425 nm, and (ii) the light transmission through the light-shielding film is 2% or less in a light wavelength region of from 425 to 650 nm.

Photosensitive resin composition used in a method for forming a

Photosensitive resin composition for use as a light-shielding film which

A water-based photopolymerizable resin composition is disclosed which is suitable for the preparation of a relief printing plate by the photolithographic techniques. The inventive composition, which basically comprises a water-soluble polymer, e.g., poly(vinyl alcohol), a photopolymerizable monomer and a photopolymerization initiator, is characterized in that at least a part of the photopolymerizable monomer is N-tetrahydrofurfuryloxymethyl acrylamide or N-tetrahydrofurfuryloxymethyl methacrylamide. By virtue of this unique ingredient in the composition, the printing plate prepared from the inventive composition is imparted with improved fidelity of pattern reproduction and durability in printing as a consequence of increased hardness and pliability to be freed from the drawback of crack formation in printing even on a cylinder of small diameter under a cold and low-humidity condition.

Water based photopolymerizable resin composition

Growing community of inventors

Atsugi, Japan

Katsuyuki Ohta