Background and overview[1]
2-[2-[2-Chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indole-2-ylidene)ethylene]-1 -Cyclohexen-1-yl]vinyl]-1,3,3-trimethyl-3H-indole 4-methylbenzenesulfonate is a cyanine dye and an infrared absorber. There are reports in the literature 2-[2-[2-chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indole-2-ylidene)ethylene]-1 -Cyclohexen-1-yl]vinyl]-1,3,3-trimethyl-3H-indole 4-methylbenzenesulfonate can be used to prepare a product with good resistance to solvents and print room chemicals Performance of positive-image infrared sensitive compositions.
Apply[1]
2-[2-[2-Chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indole-2-ylidene)ethylene]-1 -Cyclohexen-1-yl]vinyl]-1,3,3-trimethyl-3H-indole 4-methylbenzenesulfonate is used to prepare a positive-pattern infrared sensitive composition, the method is as follows:
2-[2-[2-Chloro-3-[(1,3-dihydro-1,3,3-trimethyl-2H-indole-2-ylidene)ethylene]-1 -Cyclohexen-1-yl]vinyl]-1,3,3-trimethyl-3H-indole 4-methylbenzenesulfonate, 0.2 parts by weight, purchased from DKSH Holding Ltd.;
Methyl violet, 0.14 parts by weight;
Diphenyliodonium hexafluorophosphate, 0.20 parts by weight;
Polymer, 6.16 parts by weight; the polymer includes a main chain BX-10 resin with phenolic repeating units and a substituent group covalently connected to the main chain BX-10 resin.
The preparation method of the polymer is as follows:
In a closed fume hood, add 5 parts by weight of dry BX-10 resin (purchased from Ruishi, Benxi City, Liaoning) into a four-neck round-bottomed flask equipped with mechanical stirring, a thermometer, a reflux condenser and a constant pressure funnel. Da Chemical Co., Ltd.) and 40.8 parts by weight of DMF, stir until the BX-10 resin is completely dissolved. After the DMF solution of the BX-10 resin is clarified, 0.5 parts by weight of melamine, 1.1 parts by weight of pyromellitic dianhydride and 0.5 parts by weight of hexamethylenetetramine are added in sequence, and the temperature is raised to 154°C to make the reaction solution in a reflux state. React for 8 hours. After the reaction is complete, filter, drop the filtrate into 0.75 parts by volume of water while stirring. After the dropwise addition is completed, add a mixture of 1.25 parts by volume of hydrochloric acid and 23.75 parts by volume of water to the above aqueous solution, and stir for 2 A precipitate precipitated out within 2 hours. After suction filtration, washing with distilled water and drying, the polymer (modified BX-10 resin) was obtained. As measured by GPC, the molecular weight of the modified BX-10 resin was approximately 5,000.
Dissolve 6.7 parts by weight of the positive infrared sensitive composition above in a mixed solvent of 46.65 parts by weight of PM and 46.65 parts by weight of DMF, and apply the solution on the electrochemically roughened and anodized surface using a rotating method. On the obtained aluminum plate base, and then dried in an oven at 140°C for 2 minutes, a lithographic printing plate precursor with a coating weight of 1.5g/m2 was prepared.
The positive-image infrared-sensitive composition prepared by the above method is relatively sensitive to radiation with a maximum wavelength of 700 to 1300 nm. It is an excellent infrared-sensitive composition, and the lithographic printing plate precursor made from the composition It also has good tolerance to the erosion of isopropyl alcohol. Therefore, the imageable layer prepared by using the positive-image infrared-sensitive composition described in this method is not prone to erosion and dissolution of printing chemicals during use, thus Extend the life of lithographic printing plate precursors.
References
[1][China invention, China invention authorization] CN201410222788.0 positive image infrared sensitive composition and imageable component thereof
