Photoimaging

N. S. Aden, Photopoljmerisation and Photoimaging Science and Technology, Elsevier AppHed Science, London, 1989. 

Similar types of cross-linking reactions are observed for polymers to which photosensitive molecules ate chemically attached to the backbone of the polymer stmcture (Fig. 7). Radiation curing of polymers using uv and visible light energies is used widely in photoimaging and photoresist technology (Table 8) (58,59). 

PVF resins have also been used in a variety of other appHcations, including conductive films (152), electrophotographic binders (153), as a component for inks (154), and in membranes (155,156), photoimaging (157), solder masks (158), and reprographic toners (159). 

Earlier material systems were screened epoxies, but both laminatable dry-film and Hquid uv photoimageable coatings are finding wide acceptance. These radiation-cured coatings offer high resolution and registration accuracy, and can be either epoxies or epoxy acrylates. 

Another noted and prolific Japanese author in the field of functional dyes, Masaru Matsuoka of the Laboratory of Materials Science, Kyoto Women s University, has written the second chapter, dealing with leuco-quinone dyes. These are the traditional redox leuco systems employed for so many years in the vat dyeing industry, and this chapter is an invaluable review of the chemistry of these systems, drawing on recent mechanistic and structural investigations. Applications considered include not only textile dyeing, but also other more specialized areas, such as hair dyeing, color formers, and photoimaging materials. 

The third chapter deals with leuco derivatives of the oxazine, thiazine, and phenazine dyes, and is written by Tran Van Thien, who has had many years experience in photoimaging at the 3M Research Center, Harlow. His industrial experience in leuco dyes has enabled him to produce a collation of material impossible to find elsewhere in a single review, and again recipes for the synthesis of representative examples abound. Consideration is also given to the numerous applications of these molecules in thermal and photo-imaging systems. 

Fig. 14 The molecular structures of BP-BTE and DHBO above). Microsized erasable ESIPT-fluorescence photoimaging on a spin-coated BP-BTE/DHBO-loaded PMMA film and its nondestructive readout capability (a) initial open-form state (b) writing (c) erasing (d) rewriting and (e) continuous nondestructive reading under irradiation with relatively high-intensity 415 nm light (200 4W cm-2) for 30 min. The dark region represents the area irradiated with the 365 nm UV light below) (reprint from ref. [88], Copyright 2006 American Chemical Society)...

Fig. 3 Above Spontaneous gelation mechanism between the phenylboronic acid moiety (boronate ion) in water-soluble PMBV and the hydroxyl groups (diol units) in PVA. Below Photoimages of spontaneously forming PMBV/PVA hydrogel, before gelation (left), after gelation...

Manufacture of Printed Wiring Boards. Printed wiring boards, or printed circuit boards, are usually thin flat panels than contain one or multiple layers of thin copper patterns that interconnect the various electronic components (e.g. integrated circuit chips, connectors, resistors) that are attached to the boards. These panels are present in almost every consumer electronic product and automobile sold today. The various photopolymer products used to manufacture the printed wiring boards include film resists, electroless plating resists (23), liquid resists, electrodeposited resists (24), solder masks (25), laser exposed photoresists (26), flexible photoimageable permanent coatings (27) and polyimide interlayer insulator films (28). Another new use of photopolymer chemistry is the selective formation of conductive patterns in polymers (29). 

Photoimageable polyimides, 20 278-281 Photoimageable resists, 20 280. See also Photoresists... 

This paper describes the successful synthesis and examination of polyfr-(amino /9-thiosulfate) ether] (PATE), a water soluble photolabile polymer. Evidence has been presented that the PATE polymer is zwitterionic and forms weak associations in aqueous solutions. Heat treatment of PATE films result in extensive crosslinking, presumably through a disulfide bond. This work presents strong evidence that PATE is activated by deep UV radiation, and that a disulfide crosslink is formed. Sensitization experiments demonstrate that the crosslinking reaction can be induced by a triplet sensitizer. Finally, preliminary results point out the potential for application of PATE films as active photoimaging systems. 

Pappas SP (1989) In Allen NS (ed) Photopolymerisation and photoimaging science and technology. Elsevier Applied Science, London, p 55... 

Title Positive-Working Photoimageable Bottom Antireflective Coating... 

Pappas, S.P. in Photopolymerization and Photoimaging Science and Technology Chapter 2 (Allen, N.S., Ed.), Elsevier, Essex, England (1989). 

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