Patent ID: 8138243

Claim:
A thermoplastically processable polyamide injection or extrusion molding composition comprising at least one UV absorber, for avoiding deposits on production tool surfaces in the production of transparent polyamide products or molded parts, wherein said at least one UV absorber is selected from the group consisting of 1-(4-methoxyphenyl)-3-(4-tert-butylphenyl)propane-1,3-dione and 2-(4′-diethylamino-2′-hydroxybenzoyl)benzoic acid-n-hexylester, said at least one added UV absorber being present between 0.01 and 1.0 wt. % relative to the weight of the polyamide injection or extrusion molding composition, wherein the polyamide injection or extrusion molding composition comprises at least 50 wt. % of polyamide consisting of at least one transparent polyamide, a mixture of transparent polyamides, or a blend of transparent polyamides with at least one partially crystalline polyamide, and wherein the at least one transparent polyamide is formed from at least one group consisting of: (a) at least one diamine selected from the group consisting of ethylenediamine, butanediamine, hexamethylenediamine, trimethylhexamethylenediamine, methylpentanediamine, bis(aminocyclohexyl)methane and its alkyl derivatives, bis(aminocyclohexyl)propane and its alkyl derivatives, isophoronediamine, norbornanediamine, bis(aminomethyl)norbornane, xylylenediamine, bis(aminomethyl)cyclohexane and its alkyl derivatives; and (b) at least one dicarboxylic acid selected from the group consisting of succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassylic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, octadecanedioic acid, nonadecanedioic acid, eicosanedioic acid, japanic acid, cyclohexanedicarboxylic acid, dimeric fatty acid having 36 or 44 C atoms, isophthalic acid, terephthalic acid, and naphthalenedicarboxylic acid; and (c) optionally of lactams having 4 to 15 C atoms and/or α,ω amino acids having 4 to 15 C atoms, and melts of the polyamide injection or extrusion molding material comprising said at least one UV absorber leaving no visible blooming on surfaces with which they come into contact during processing or production of transparent polyamide products or transparent polyamide molded parts.