The kinetic behavior of reaction of dibasic acid half ester with epoxy compound, which is one of the key reaction occurring in the technology of liquid alkali developing type solder resists, was investigated in this paper, by using the monomethyl esters of maleic acid, succinic acid, phthalic acid, cis 1,2,3,6 tetrahydrophthalic acid and cis hexahydrophthalic acid as model compounds. It was found that for the reaction catalyzed by tetramethyl ammonium bromide(TMAB), the reaction order for dibasic acid half ester and for PGE is 0 5 and 1 respectively when the dibasic acid monomethyl esters with a smaller size and/or with a stronger acitity were used, while it is 0 and 1 respectively when the dibasic acid monomethyl esters with a larger size and a weeker acitity were used. The reaction mechanism has also been discussed, from which a rate equation has been obtained which is in agreement with the experiment results.
