Fuji Photo Film Company, Limited

Toshio Uchida

Hiroshi Matsumoto

Kenji Kunichika

Teppei Ikeda

Yorimiti Yabuta

Nobuyuki Kita

Akihiro Matsufuji

Syunichi Kondo

Hiromichi Tachikawa

Hisao Ohba

Yasuhiro Noguchi

Azusa Ohashi

Eiichi Hasegawa

Hisatake Ono

Sadaharu Ikeda

Shigeru Sato

Shigeru Sasaki

Hiroshi Noguchi

A dampening water composition for lithographic printing plate comprises a hydrophilic polymer having a film-forming ability, a pH-buffering substance and at least one compound selected from the group consisting of benzimidazole and derivatives thereof. The dampening water composition can effectively suppress the corrosion of copper or copper alloy-plated rolls of a printing press as well as cast iron or nickel-plated cast iron parts thereof without impairing printing effects and printability.

Dampening water composition for lithographic printing and method for

Disclosed is a dampening solution composition for lithographic printing. The solution has a dynamic surface tension ranging from 20 to 50 dyne/cm at 15.degree. C. at most 1.times.10.sup.-1 seconds after a new surface of the solution is formed on the surface of a printing plate; a viscosity ranging from 1.05 to 5.0 cSt at 15.degree. C.; and an emulsification ratio when mixed with ink which is higher by 2 to 30% than that of pure water mixed with ink.

Dampening solution composition for lithographic printing

A dampening water composition for lithographic printing which comprises 0.1 to 5% by weight of at least one member selected from the group consisting of monoalcohols or diols of alkanes or alkenes having 5 to 11 carbon atoms, to which 1 to 10 moles of ethylene oxide and/or propylene oxide are added. The dampening water composition is not toxic, has not a possiblity of causing a fire and pollution of working atmosphere and, therefore, the use of a local exhaust installation is not necessary. Moreover, it is excellent in characteristics as dampening water such that it does not cause contamination of metering roll, has good bleeding properties, emulsifying properties and stability in continuous processing as well as low foaming properties. Thus, the composition makes printing operation quite stable.

Dampening water composition for lithographic printing and additive for

The present invention relates to a concentrated dampening water for a lithographic printing plate characterized by comprising:

Dampening water composition for lithographic plate

A method of replenishing a developer during the development of photosensitive plates in a conveyor-type automatic developing machine connected to a replenishing device in which the dissolution of the photosensitive layer in the non-image area of a photosensitive plate is measured with a sensor. The sensor is positioned at a certain point in the developing zone of the machine, and, when the measured dissolution reaches a certain level, the replenishing device is automatically actuated to supply a predetermined amount of replenisher to the developer.

Method of replenishing a developer for photosensitive plate

A desensitizer for a lithographic printing plate, which contains:

Process for preparing lithographic printing plate using silicate

A photopolymerizable composition comprising a polymerizable ethylenically unsaturated compound, optionally, a linear organic polymer, and a photopolymerization initiator comprising a combination of a compound represented by the general formula (I) ##STR1## wherein Z represents the non-metal atomic group necessary to form a nitrogen containing heterocyclic nucleus, R.sub.1 represents an alkyl group or a substituted alkyl group, and R.sub.2 represents an alkyl group or an aryl group having a comparatively high photopolymerization initiating ability; and a compound represented by the general formula (II) ##STR2## wherein X represents a halogen atom, Y represents --CX.sub.3, --NH.sub.2, --NHR.sup.1, --NR.sup.1.sub.2 or OR.sup.1, R.sup.1 represents an alkyl group or an aryl group and R represents an alkyl group, an alkyl group substituted with at least one chlorine atom, an aryl group, a substituted aryl group or a substituted alkenyl group.

Photopolymerizable composition

2-Arylnaphtho[1,8-bc]furan-5-ones represented by general formula (I): ##STR1## wherein G represents a substituted phenyl group, an unsubstituted or substituted 1-naphthyl group and an unsubstituted or substituted 2-naphthyl group, with the substituents being selected from the group consisting of a straight chain or branched chain alkyl group having 1 to 5 carbon atoms, a straight chain or branched chain alkoxy group having 1 to 3 carbon atoms and a halogen atom; are disclosed as well as photopolymerizable compositions containing at least one of the above compounds as a photopolymerization initiator for addition polymerizable ethylenically unsaturated compounds.

2-Arylnaphtho[1,8-BC]furan-5-ones

A step tablet in which density steps of a definite shape, each density step having a specific optical density, form a series of decreasing or increasing densities, in which any two density steps contiguous to each other are disposed with a boundary space of a specific shape between the density steps.

Step tablet

A light-sensitive lithographic printing plate element suitable for the formation of negative and positive images, simultaneously, comprising a hydrophilic support having, in succession, a light-sensitive composition layer and a transparent cover film in which images for printing are formed by imagewise exposing through the cover film and peeling apart to remove, together with the cover film, the areas having a stronger adhesion to the cover film in the light-sensitive composition layer by utilizing the difference in adhesion to the support and to the cover film between the exposed areas and the unexposed areas of the light-sensitive composition layer, whereby the areas of the light-sensitive composition layer having a stronger adhesion to the support remain on the support, wherein the surface of the support adjacent the light-sensitive composition layer is treated with an aqueous solution containing at least one water soluble oxygen acid or water soluble oxygen acid salt selected from the group consisting of boric acid, boric acid salts, molybdic acids, molybdic acids salts, phosphoric acids, phosphoric acid salts, vanadic acids, vanadic acid salts, tungstic acids, tungstic acid salts, chromic acid, chromic acid salts, silicic acids and silicic acid salts.

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Shizuoka, Japan

Toshio Uchida