Irradiation photopolymers

In liquid crystal display cells comprising a liquid crystal disposed between two substrate plates provided with drive electrodes, the orientation layer on the inner sides of the plates where the electrodes are disposed comprises an oriented photopolymer layer. This layer is formed by irradiating photopolymer layer. This layer is formed by irradiating photoreactive material with linear polarized light. 

The polymerization proceeds under photo- [49,50],X-ray [51], and y-ray [52] irradiation in the dark in vacuo, in air, or even in water or organic solvent as the dispersant (nonsolvent) for the crystals, similar to the solid-state polymerization of diacetylene compounds [ 12]. The process of topochemical polymerization of 1,3-diene monomers is also independent of the environment surrounding the crystals. Recently, the thermally induced topochemical polymerization of several monomers with a high decomposition and melting point was confirmed [53]. The polymer yield increases as the reaction temperature increases during the thermal polymerization. IR and NMR spectroscopies certified that the polymers obtained from the thermally induced polymerization in the dark have a stereoregular repeating structure identical to those of the photopolymers produced by UV or y-ray irradiation. 

Detailed analyses of each of these major classes of photopolymer sensitization will be presented below. A related process which is sensitive to visible light, which will not be discussed, is irradiation of charge transfer complexes, exemplified by the initiating complex between isoquinoline and bromine. See ref. 13. 

Polymeric fullerene materials can be obtained by many methods, for example by irradiation with electrons or ions, treatment in a plasma generator, doping with alkali metals [9,28,46], direct chemical synthesis [47], or mechanical milling [29]. Because of the small penetration depth of light fullerenes can only be photopolymerized as thin films, but bulk photopolymer can be obtained by polymerization in solution [48,49]. Diffraction studies show that photopolymers usually have a disordered fee structure. Although some ordered films have been... 

D Systems Inc., Valencia, CA, u.S.A. Stereo lithography Apparatus (SLA) Photopolymer system point-by-point irradiation with a HeCd resp. an argon ion laser... 

Light Sculpting Inc., Milwaukee, WI, U.S.A. LSI Photopolymer system irradiation of the entire surface with a UV lamp... 

In all previous examples discussed, the monomer molecules participate in the excited states reactions, which give the initiating species X. Another principle for the utilization of PET in photopolymer systems consists of the use of donors and acceptors that are independent of the monomer molecule. Then, that combination of both compounds is a true photoinitiator system, and it supplies the initiating species X after irradiation. This variant is more widely usable, and possesses a greater variability with respect to light absorption. 

We found that when 4.4 -diazidodiphenylamine in novolak was irradiated by UV light, novolak was in-solubilized in alkali aqueous solution and colored in blacki But it is impossible to use it as photopolymer for plate-making because 4.4 -diazidodiphenylamine is very dangerous causing explosion during storage. 

Khattak and Wang (1969) have isolated two products from uracil irradiated with ultraviolet light in frozen aqueous solution. Evidence from NMR, UV, IR, and mass spectra suggest that one is a photopolymer, Uj, and the other is probably 6-4 -[pyrimidin-2 -one]-uracil. 

The printing plate, covered with the polymerizable material, often incorrectly referred to as the photopolymer, is irradiated through a film negative to initiate photocuring. Thereby, the areas of the photosensitive layer corresponding to the... 

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