Benzophenone-type light initiator and preparation method thereof

Abstract

The invention discloses a benzophenone-type light initiator shown in the formula (1). As the benzophenone-type light initiator is used, the mobility of benzophenone is lowered greatly during the using process while the triggering activity of the benzophenone is not lowered, i.e. the yellow-stain phenomenon is lightened. Particularly, a tertiary amine structure is contained in the self molecular structure of the benzophenone-type light initiator, i.e. the tertiary amine structure can be effectively used as an H donor of an active functional group, so that the benzophenone-type light initiator can be triggered without additionally adding an active amine additive during the using process. Therefore, the benzophenone-type light initiator belongs to a hydrogen-seizing type light initiator which is triggered automatically. In addition, the benzophenone-type light initiator has good solubility in various resins and resin oligomers, thereby being a good BP (benzophenone) substitute.

Description

technical field [0001] The invention relates to a benzophenone photoinitiator and a preparation method thereof, in particular to a benzophenone photoinitiator without adding active amines and a preparation method thereof. technical background [0002] Benzophenone (BP) has become one of the most widely used photoinitiators in the field of photocuring because of its simple structure, easy synthesis, and low price. Light can also absorb part of visible light, so it shows good surface curing ability; at the same time, benzophenone has a moderate melting point and good compatibility with other materials, so it is widely used in plastics, inks, paints, cosmetics, etc. industry. [0003] Benzophenone also has certain defects, such as: benzophenone is sublimable and volatile, and it is easy to migrate from printed matter to food or medicine during the curing process; the curing speed of benzophenone is slow, and it is easy to make the cured coating Yellowing; it needs to be used ...

AI Technical Summary

Problems solved by technology

[0003] Benzophenone also has certain defects, such as: benzophenone is sublimable and volatile, and it is easy to migrate from printed matter to food or medicine during the curing process; the curing speed of benzophenone is slow, and it is easy to make the cured coating Yellowing; it needs to be used in conjunction with active amines during use; in recent years, with the strengthening of people's awareness of environmental protection, consumers have become increasingly sensitive to the pollution of foreign compounds in food, pharmaceutical and other industries, and the government's relevant environmental protection policies have also become more and more serious. The more stringent, the defects of benzophenone have caused a downward trend in the use of benzophenone. It is expected that with the introduction of relevant policies, this trend will become more and more obvious in the next few years; in order to deal with this situation, in recent years Since then, the modification of the photoinitiator BP has become a research hotspot

[0004] As we all know, macromolecular photoinitiators can effectively inhibit the volatility and mobility of small molecular photoinitiators. Chinese patent: CN101434543A reports a macromolecular benzophenone derivative, which is passed through a branched chain diphenone derivative. Alcohol is obtained by coupling two benzophenone molecules. Although the mobility of benzophenone has been greatly improved, due to the large molecular weight, the density of active functional groups in the molecular structure is not enough, and the amount of addition is large when used. lost market competitiveness;

[0005] Chinese patent: CN102766045A reports a derivative called 4-phenyl-3'-(pivaloyloxy)benzophenone, which is made of 3-pivaloyloxybenzoic acid as a raw material. It reacts with thionyl chloride to synthesize acid chloride, and then reacts with biphenyl through Friedel-Crafts acylation reaction. The introduction of biphenyl group makes this benzophenone derivative also reduce the volatilization of benzophenone to a certain extent nature, but the molecular conjugation is stronger, and more serious yellowing will occur during the photocuring process. In addition, the photoinitiator also requires the use of active amines to achieve good results

[0006] Chinese patent: CN101735105A reports a derivative called 2-chloro-4,-phenylbenzophenone. The structure of the molecule introduces phenyl and chlorine atoms respectively on the two benzene rings of benzophenone, effectively The generation of free benzene has been prevented, and the odor and yellowing of benzophenone have also been improved, but compared with benzophenone, the compatibility of this derivative in various materials is not good. Like the initiator, this derivative also requires the addition of a reactive amine to work

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