Process for the preparation of condensed phosphoric acid esters
AssigneeDaihachi Chemical Industry Co., Ltd.
InventorsShin Nakamura, Taku Fujisawa, Takafumi Okawa
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Abstract
An objective of the present invention is to provide a method for preparing a high-purity, condensed phosphoric ester made of a bisphenol A derivative and having a very low content of monomer-type phosphoric ester that causes reduction in the heat resistance and the contamination of the molds during the molding when the condensed phosphoric ester is used as an additive for a resin. According to the present invention, a bisphenol A derivative, a phosphorus oxytrihalide and a hydroxy compound are reacted in the presence of a decomposition retardant, whereby the above problems can be solved.
Claims12
A method for preparing a condensed phosphoric ester, comprising a process of reacting a bisphenol A derivative, wherein
- the bisphenol A derivative refers to bisphenol A or a derivative thereof, which is represented by the following formula (A):
- where R5 and R6 are the same or different from each other and represent an alkyl group containing 1 to 3 carbon atoms;
- and n1 and n2 each represent an integer from 0 to 4,
- a phosphorus oxytrihalide, and a hydroxy compound in the presence of a decomposition retardant.
Dependencies are inferred from the claim text.