Volume phase hologram recording material and optical information recording medium

A volume phase hologram recording material precursor which comprises mainly containing a polymer matrix-forming material (A), a photoradically polymerizable monomer (b), and a photoradical polymerization initiator (c) wherein the polymer matrix-forming material (A) contains 0.5-40 wt % of a matrix-forming compound having photoradically polymerizable groups (a1) and a matrix-forming compound having no photoradically polymerizable group (a2), a three-dimensional crosslinked polymer matrix is formed by a polymerization reaction other than a photoradical polymerization reaction, and the aforementioned matrix-forming compound having radically polymerizable groups (a1) is an unsaturated compound represented by the following formula (1):

• in formula (1), Ar is a divalent group having one or more aromatic rings, R1 and R2 each is independently a hydrogen atom or a methyl group, L1 is an oxygen atom, a sulfur atom, or —(OR3)nO—, R3 is an alkylene group, n is an integer of 1-4, and L2 is a divalent group optionally having aromatic rings
• wherein the photoradically polymerizable groups to be introduced to the three-dimensional crosslinked polymer matrix is in a concentration of 0.01-0.2 mol/kg of the whole polymer matrix-forming material (A).

A volume phase hologram recording material which comprises mainly containing (a) a three-dimensional crosslinked polymer matrix, (b) a photoradically polymerizable monomer, and (c) a photopolymerization initiator wherein the three-dimensional crosslinked polymer matrix (a) has photoradically polymerizable groups and is formed from a polymer matrix-forming material (A) containing 0.5-40 wt % of a matrix-forming compound having photoradically polymerizable groups (a1) and a matrix-forming compound having no photoradically polymerizable group (a2) and the aforementioned matrix-forming compound having photoradically polymerizable groups (a1) is represented by the following formula (2) or (3):

• in these formulas, R1 is independently a hydrogen atom or a methyl group, R4 is independently a hydrogen atom or an alkyl group of 1-4 carbon atoms, R5 is a hydrogen atom, a halogen atom, an alkyl group of 1-4 carbon atoms, or an alkoxyl group of 1-4 carbon atoms, L1 is an oxygen atom, a sulfur atom, or —(OR3)nO—, L3 is an oxygen atom, a sulfur atom, —C(O)O—, or —N(R6)—, n is an integer of 1-4, R3 is an alkylene group, and R6 is a hydrogen atom or an alkyl group of 1-4 carbon atoms
• wherein the photoradically polymerizable groups to be introduced to the three-dimensional crosslinked polymer matrix is in a concentration of 0.01-0.2 mol/kg of the whole polymer matrix-forming material (A).