2results about How to "Low birefringence" patented technology

The object of this invention is to provide a cyclic olefin ring-opening polymer hydride with a suitable Abbe number and low birefringence, and the raw materials thereof. The cyclic olefin ring-opening polymer of this invention is characterized by comprising structural units (A) from 1,2,3,3a,4,6a-hexahydro-1,2,4-methyl-bridged pentanene and structural units (B) from a cyclic olefin monomer having an aromatic ring structure. Furthermore, the cyclic olefin ring-opening polymer hydride of this invention is characterized by being formed by hydrogenating the cyclic olefin ring-opening polymer of this invention.

The purpose of the present invention is to provide: a cyclic olefin ring-opening polymer hydride which has both an Abbe number of an appropriate size and a low birefringence; and a starting material for the cyclic olefin ring-opening polymer hydride. This cyclic olefin ring-opened polymer is characterized by containing a structural unit (A) derived from a norbornene imide monomer represented by formula (1) and a structural unit (B) derived from a cyclic olefin monomer that does not have a polar group. The cyclic olefin ring-opening polymer hydride according to the present invention is characterized by being obtained by hydrogenating the cyclic olefin ring-opening polymer according to the present invention.