Radiation imagery chemistry: process – composition – or product th – Diazo reproduction – process – composition – or product – Composition or product which contains radiation sensitive...
Reexamination Certificate
2002-01-15
2004-09-28
Chu, John S. (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Diazo reproduction, process, composition, or product
Composition or product which contains radiation sensitive...
C430S162000, C430S271100, C430S273100, C430S281100, C430S920000, C430S921000, C101S465000, C101S466000, C101S467000
Reexamination Certificate
active
06797449
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an image-recording material usable for planographic printing plate precursors, color proofs, photoresists and color filters, and to novel cyanine dyes favorable for it. In particular, the invention relates to a negative image-recording material for heat-mode exposure systems, which is usable for a planographic printing plate precursor on which an IR laser is scanned on the basis of the digital signals from a computer or the like to directly make a planographic printing plate; and relates to novel cyanine dyes of high IR absorbing property.
2. Description of the Related Art
For a system of directly making printing plates from digital data of a computer, heretofore proposed have been <1> electrophotography, <2> exposure of photopolymerizable materials to blue or green-emitting lasers, <3> silver salts lamination on photosensitive resin, and <4> silver diffusion transfer photography.
However, these all have some drawbacks. Specifically, the image-forming process of electrophotography <1> is troublesome, in requiring complicated steps of electric charging, exposure to light and development, and this requires a complicated, large apparatus. Photopolymerizable plates for <2> are highly sensitive to blue and green light, and are difficult to handle in light rooms. In the processes of <3> and <4> using silver salts, development is troublesome, and, in addition, the wastes contain silver.
On the other hand, the recent development of laser technology has been remarkable, and high-power, small solid lasers and semiconductor lasers for emitting IR radiation within a wavelength range of from 760 nm to 1200 nm are easily available. For a light source for directly making a printing plate from digital data of a computer or the like, these lasers are extremely useful. However, many practicable photosensitive recording materials are sensitive to visible light falling within a wavelength range of at most 760 nm, to which, therefore, these IR lasers are not applicable for recording images thereon. Accordingly, recording materials capable of being processed with IR lasers are desired.
An image-recording material capable of being processed with an IR laser is described in U.S. Pat. No. 4,708,925, which includes an onium salt, a phenolic resin and a spectral sensitizer. This is a positive image-recording material, in which the onium salt and the phenolic resin express dissolution resistance to developers, and is not a negative image-recording material as in the present invention. On the other hand, a negative image-recording material is disclosed in U.S. Pat. No. 5,340,699, which includes an IR absorber, an acid generator, a resol resin and a novolak resin. For image formation thereon, however, this material requires heat treatment after exposure to a laser. Therefore, a negative image-recording material not requiring heat treatment after exposure to light has been desired.
For example, Japanese Patent Application Publication (JP-B) No. 7-103171 discloses a recording material that includes a cyanine dye having a specific structure, an iodonium salt, and an ethylenically unsaturated double bond-having addition-polymerizable compound. This does not require heat treatment after imagewise exposure to light. However, the strength of the image area of this material is low. Therefore, this is unfavorable for planographic printing plates, as the number of prints from a planographic printing plate is small.
SUMMARY OF THE INVENTION
The object of the invention is to provide a negative image-recording material which can be imagewise exposed to IR rays from an IR-emitting solid laser or semiconductor laser to directly make a printing plate from the digital data of a computer or the like, and which, when the obtained printing plate is used as a planographic printing plate, ensures well cured image formation on the printing plates even though not heated for image formation thereon, and therefore exhibits good printing durability to ensure a large number of good prints from the printing plates; and to provide novel cyanine dyes favorable for IR absorbents for the image-recording material of the type having the excellent characteristics as above.
Having specifically noted the constituent components of negative image-recording materials and having assiduously studied them, the present inventors have found that, when a cyanine dye having a specific partial structure is used for the IR absorbent in a negative image-recording material, then the above-mentioned object can be attained. On the basis of this finding, the present inventors have completed the invention.
Specifically, the invention provides a negative image-recording material for heat-mode exposure systems, which comprises (A) an IR absorbent including cyanine dye having an electron-withdrawing group or a heavy atom-containing substituent in at least one terminal aromatic ring, (B) a radical generator such as onium salts and (C) a radically-polymerizable compound, wherein images are formed therein by imagewise exposure to IR rays.
The invention also provides a negative image-recording material for heat-mode exposure systems, which comprises (A′) an IR absorbent of the following general formula (1), (B) a radical generator and (C) a radically-polymerizable compound.
A
+
−Q=B X
−
(1)
wherein
In formula (1), A
+
and B are terminal groups represented by the formulae mentioned above; and R
1
and R
2
each independently represent an optionally-substituted hydrocarbon group having at most 20 carbon atoms. Ar
1
and Ar
2
may be the same or different, each representing an optionally-substituted aromatic hydrocarbon group or heterocyclic group. Y
1
and Y
2
may be the same or different, each representing a sulfur atom, an oxygen atom, a selenium atom, a dialkylmethylene group having at most 12 carbon atoms, or —CH═CH—. Z
1
and Z
2
may be the same or different, each representing a substituent selected from a hydrocarbon group, an oxy group, an electron-withdrawing substituent and a heavy atom-containing substituent, and at least one of Z
1
and Z
2
is an electron-withdrawing group or a heavy atom-containing substituent. n and m each independently indicate 0 or a positive integer, and the sum of n and m is at least 1.
Q represents a pentamethine group or a heptamethine group, optionally substituted by substituent(s) selected from an alkoxy group, an aryloxy group, an alkylthio group, an arylthio group, a dialkylamino group, a diarylamino group, a halogen atom, an alkyl group, an aralkyl group, a cycloalkyl group, an aryl group, an oxy group and a substituent of the following general formula (2); and Q may have a cyclohexene, cyclopentene or cyclobutene ring containing continuous three methine chains.
wherein R
3
and R
4
each independently represent a hydrogen atom, an alkyl group having from 1 to 8 carbon atoms, or an aryl group having from 6 to 10 carbon atoms; and Y
3
represents an oxygen atom or a sulfur atom. X
−
represents a counter anion optionally existing for charge neutralization of the compound of formula (1).
Preferably, the cyanine dyes of formula (1) have halogen atoms or carbonyl substituents in the two terminal aromatic rings.
In addition, the present invention provides a negative image-recording material f or heat-mode exposure systems, which comprises (A″) an IR absorbent of the following general formula (3), (B) a radical generator and (C) a radically-polymerizable compound, wherein images are formed therein by imagewise exposure to IR rays:
wherein R
5
and R
6
each independently represent a linear or branched alkyl group having at most 20 carbon atoms, optionally substituted with any of an aryl group, an alkenyl group, an alkoxy group, a hydroxyl group, a sulfo group, a carboxyl group and an acyloxy group;
Ar
3
and Ar
4
each independently represent a hydrogen atom, an alkyl group having from 1 to 4 carbon atoms, or an aryl group having f
Nakamura Ippei
Sorori Tadahiro
Burns Doane Swecker & Mathis L.L.P.
Chu John S.
LandOfFree
Negative image-recording material and cyanine dye does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Negative image-recording material and cyanine dye, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Negative image-recording material and cyanine dye will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3200966