DETAILED DESCRIPTION The photopolymerizable composition of matter of my invention comprises, in its simplest form, a mixture of: a.
from about 70-95%, by weight, of an alcohol-soluble linear polyamide; b.
from about 0.
5-15%, by weight, of a low molecular weight dicarboxylic acid diester; and c.
an effective amount of at least one photosensitizer and at least one polymerization inhibitor.
The polyamide component of this composition may be any of the polyamides that are conventionally used in photopolymeric compositions.
These include copolyamides that are soluble in common solvents or mixtures of solvents, such as lower aliphatic alcohols or mixtures of these alcohols with water, ketones, or aromatic compounds.
Typically, copolyamides are prepared by polycondensation or activated anionic polymerization of two or more lactams having from five to thirteen ring members, or by polycondensation of the appropriate dicarboxylic acids and diamines, as is well known to those skilled in the art.
Particularly suitable linear polyamides are those described in U.
S.
Pat.
Nos.
3,512,971; 3,516,828; and 4,144,073, the disclosures of which are hereby incorporated by reference.
By the term "low molecular weight dicarboxylic acid diester" is meant saturated and unsaturated dicarboxylic acid diesters having up to eight carbon atoms in the acid backbone and up to about four carbon atoms in the alcohol moiety appended at the ester linkage.
Preferred diesters include diethyl malonate, diethyl fumarate, diethyl sebacate, dipropyl adipate, and diethyl maleate.
There is some evidence, although presently inconclusive, that the resistance of the photopolymer of my invention to certain strong organic solvents, such as methyl ethyl ketone, decreases with increasing molecular weight of the acid portion of the diester component.
Hence, the most preferred diester components of my photopolymerizable composition are those having short acid backbones, i.
e.
, diethyl malonate, diethyl fumarate, and diethyl maleate.
The photosensitizers suitable for use in my composition are those compounds that decompose to radicals upon exposure to light or irradiation and initiate polymerization
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Manufacturing Materials 
