摘要:
A process for generation of acid uses a medium comprising a first acid-generating component capable of generating a first acid, and a secondary acid generator, this secondary acid generator being capable of thermal decomposition to form a secondary acid, the thermal decomposition of the secondary acid generator being catalyzed by the first acid. At least part of the medium is exposed to so as to cause formation of the first acid from the first acid-generating component; and the medium is then heated to cause, in the exposed part of the medium, acid-catalyzed thermal decomposition of the secondary acid generator and formation of the secondary acid. The secondary acid generator has a first site bearing a first leaving group and a second site bearing a second leaving group, the first leaving group being capable of protonation by the first acid, with expulsion of the first leaving group to form a cation which electrophilically adds to an unsaturated reagent bearing a proton at the site of addition and a proton-containing nucleophilic grouping at an adjacent site, following which said proton on the reagent is lost and the second leaving group is displaced by said nucleophilic grouping, the second leaving group, in combination with a proton, forming the secondary acid. Preferred variants of the process are of the types described in U.S. Pat. Nos. 5,286,612; 5,334,489; 5,395,736; 5,441,850 and 5,453,345.
摘要:
A holographic recording medium comprises an acid generator capable of producing an acid upon exposure to actinic radiation; a binder; and at least one monomer or oligomer capable of undergoing cationic polymerization initiated by the acid produced from the acid generator. This recording medium is not subject to the disadvantages (for example, oxygen sensitivity) associated with radical-polymerized prior art holographic recording media.
摘要:
Acid can be generated by exposing a superacid precursor to actinic radiation effective to generate superacid from the superacid precursor and heating the superacid in admixture with a secondary acid generator capable of undergoing thermal decomposition to produce a secondary acid. The superacid catalyzes decomposition of the secondary acid generator, thus increasing the quantity of strong acid present in the medium. The resultant secondary acid can be used to effect a color change in an acid-sensitive material, so providing an imaging process.
摘要:
Ethylenically unsaturated polymerizable acrylic (or methacrylic) monomers having pendant halogenated carbazole moieties, useful for the production of high refractive index polymers, are disclosed. The monomers are useful for the bonding of optical elements in the fabrication of optical devices.
摘要:
A class of polyesters comprising recurring units having certain bis(trifluoromethyl)biphenylene radicals is disclosed. The polyesters exhibit favorable solubility properties in certain organic solvents so as to facilitate the production of the polyesters via polycondensation methods to film- and fiber-forming molecular weights. Monomeric compounds comprising a bis(trifluoromethyl)biphenylene radical and useful for the production of the polyesters are also disclosed.
摘要:
A class of polyesters comprising recurring units having certain bis(trifluoromethyl)biphenylene radicals is disclosed. The polyesters exhibit favorable solubility properties in certain organic solvents so as to facilitate the production of the polyesters via polycondensation methods to film- and fiber-forming molecular weights. Monomeric compounds comprising a bis(trifluoromethyl)biphenylene radical and useful for the production of the polyesters are also disclosed.
摘要:
New polymers are disclosed comprising recurring units of the formula ##STR1## wherein R is hydrogen or lower alkyl containing from 1 to 5 carbon atoms, L is a divalent linking group, and each X is independently chloro or bromo. The polymers are capable of providing a relatively high index of refraction in combination with a relatively high Abbe number and can be utilized as raw materials in the manufacture of plastic optical articles or elements such as lenses or prisms and in the manufacture of optical films and coatings.