Patent GB-925554-A (GB)
Title: Method of protecting synthetic resins from ultraviolet light deterioration
IPC: C08K5/29
Filed: 1960-01-04
Abstract: Oxalimidic acid hydrazides of the formula <FORM:0925554/IV(a)/1> where R1 is hydrogen or methyl and R2, wherein a double bond is conjugate to the C=N double bond, is a C2-7 alkyl radical or an aromatic radical having less than three rings wherein any substituents are selected from alkyl, C1-7 alkoxy, halogen, hydroxy, nitro and dialkylamino are used as ultra-violet light absorbers for synthetic resins (see Group IV(b)).  They may be prepared from oxamide dihydrazone and the appropriate aldehyde or ketone.  Groups R2 and R4 mentioned are CH2=CH (from acrolein); CH3-CH=CH-(from crotonaldehyde); CH2=C-CH3 (from methacrolein); phenyl; naphthyl; diphenyl; furyl; thienyl; thiazolyl; pyridyl and quinolyl. Substituted (preferably ortho) aromatic radicals may be derived from the corresponding substituted aldehyde.  A long list of aldehydes includes those with one or more of the following substitutes:- chlorine, bromine, fluorine, iodine, nitro, hydroxy, C1-4 alkoxy, diethylamino and methyl.  The preparation of oxalimidic acid bis(benzylidene hydrazide) is described.  The absorption properties are given of a number of compounds identified by their formulae including, for comparison, oxalimidic acid bis-(isopropylidene hydrazide).  The Specification includes a very extensive catalogue of synthetic resins with multitudinous examples of resins of the following classes: polymers and copolymers of vinyl acetals and esters, acrylic acid and its derivatives, aliphatic and aromatic olefines, halo-olefines, vinylsubstituted heterocyclic compounds and unsaturated polyester resins; polyamides; condensates of formaldehyde or hexamine with ureas, amines, alcohols and phenols; silicones; alkyd resins; cellulose ethers and esters; epoxy resins; and polyglycols.  In specific examples the hydroxides are incorporated in the following materials:- (3) and (7) nylon; (4) a polyvinyl chloride composition containing dioctyl phthalate, barium-cadmium laurate and triaryl phosphite; (5) polystyrene; and (6) cellulose acetate.ALSO:Oxalimidic acid hydrazides of the formula <FORM:0925554/IV(a)/1> wherein R1 is hydrogen or methyl and R2, which has a double bond conjugate to the C=N double bond, is a C2-7 alkenyl radical or an aromatic radical having less than three rings wherein any substituents are selected from alkyl, C1-7 alkoxy, halogen, hydroxy, nitro and dialkylamino are used as ultra violet light absorbers for synthetic resins (see Group IV(a)). They may be prepared from oxamide dihydrazone and the appropriate aldehyde or ketone.  Groups R2 mentioned are CH2=CH (from acrolein); CH3- CH=CH- (from crotonaldehyde); <FORM:0925554/IV(a)/2> (from methacrolein); phenyl; naphthyl; diphenyl; furyl; thienyl; thiazolyl; pyridyl and quinolyl.  Substituted (preferably ortho) aromatic radicals may be derived from the corresponding substituted aldehyde.  A long list of aldehydes includes those with one or more of the following substitutes:- chlorine, bromine, fluorine, iodine, nitro, hydroxy, C1-4 alkoxy, diethylamino and methyl.  The preparation of oxalimidic acid bis (benzylidene hydrazide) is described.  The absorption properties are given of a number of compounds identified by their formulae including, for comparison, oxalimidic acid bis-(isopropylidene hydrazide).