2-(2'-HYDROXYPHENYL)BENZOTRIAZOLES USED AS U.V. STABILISERS

Abstract: 2-(2'-hydroxyphenyl)benzotriazoles having general formula (I). The above 2-(2'-hydroxyphenyl)benzotriazoles are useful as light stabilizers for organic polymers.

Description: -(2'-HYDR0XYYPHENYL)BENZ0TRIAZ0LES USED AS U.V. STABILISERS The present invention relates to 2-(2'-hy- droxyphenyl) benzotriazoles. More specifically, the present invention relates to 2- (2 '-hydroxyphenyl) benzotriazoles containing a 2, 4-imidazolidinedione group or a 2 , 4-imidazolidine- dione-5, 5-disubstituted group in the molecule, a process for their preparation and their use as light stabilizers for organic polymers. The present invention also relates to the polymeric compositions stabilized with the above benzotriazoles and to the end-products obtained from these compositions. 2- (2 '-hydroxyphenyl) benzotriazoles which can be used as light stabilizers are known in the art. These benzotriazoles however have various disadvantages. In fact, they are often rather volatile, they have a low thermal stability and, as they sometimes have a signi- ficant absorption at 400 nm, they give the polymers, into which they are incorporated, a yellow colouring. The Applicant has now surprisingly found that 2- (2 '-hydroxyphenyl) benzotriazoles containing a 2,4- imidazolidinedione group or a 2, 4-imidazolidinedione- 5, 5-disubstituted group in the molecule, are capable of overcoming the drawbacks of the known art. In fact, the above benzotriazoles have a low volatility (they are therefore able to remain inside the stabilized organic polymer for a longer period) and also a high thermal stability. In addition, they have a low absorption at λ = 400 n and maintain the absorption at the two λ typical of benzotriazoles, at about 300 nm and 340 nm and consequently they do not give a yellow colouring to the polymers into which they are incorporated. The present invention therefore relates to 2- (2 '-hydroxyphenyl) benzotriazoles having general formula (I) : wherein: - X represents a hydrogen atom; a halogen atom selected from chlorine and bromine; a linear or branched 0,-C^ alkyl group; a linear or branched C^-C,^ alkoxyl group; a cyano group; R represents a halogen atom selected from chlorine and bromine; a linear or branched C^-C^ s alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a C 5 -C 18 cycloalkyl group, said cycloalkyl group optionally substituted; a C 6 -C 15 arylalkyl or alkylaryl group; a C 6 -C u aryl group, said aryl group optionally substituted; a linear or branched C^-C^ alkoxyl group; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted; a group having the formula: O II C H; a -C0R 4 group or a -NR 5 R 6 group wherein R 4 , Ε^ and R 6 , the same or different, represent a linear or branched C^-C^ alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a C 5 -C 18 cycloalkyl group, said cycloalkyl group optionally substituted; a C 7 -C 15 arylalkyl or alkylaryl group; a C 6 -C 14 aryl group, said aryl group optionally substituted; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substi- tuted; or R represents an ester group having general formula (II) , (III) or (IV) : 0 / O (II) \ OR' or an amide group having general formula (V) : 0 \\ —CH 2 CH 2 C—NH—R' (V) wherein R' represents a linear or branched C.,-C 18 alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a C 5 -C 18 cycloalkyl group, said cycloalkyl group optionally substituted; a C 7 -C 15 arylalkyl or alkylaryl group; a C 6 -C 14 aryl group, said aryl group optionally substituted; a linear or branched C^-C^ g alkoxyl group; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted; or R represents a 4 , 4 '-ethylidenebisphenol group having formula (VI) : R 1 represents a hydrogen atom; a linear or branched C^-C^ alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a C 5 -C 18 cycloalkyl group, said cycloalkyl group optionally substituted; a C 7 -C 15 arylalkyl or alkylaryl group; a 6 -C^ aryl group, said aryl group optionally substituted; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted; an acyl group having general formula (VII) : 0 / R' C (VII) or an ester group having general formula (VIII) : 0 / R 1 — OC (VI I I ) wherein R' has the same meanings described above; R 2 and R 3 , the same or different, represent a hydrogen atom; a linear or branched Cj-Cι 8 alkyl group; a phenyl group; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted. The compounds having general formula (I) can be used as light stabilizers for organic polymers. When the C 5 -C 18 cycloalkyl grou s, the C 6 -C 14 aryl groups and the heterocyclic groups with 5 or 6 atoms are defined as being optionally substituted, these groups are substituted with: halogen atoms selected from chlorine and bromine, linear or branched Ci-Cig alkyl groups, linear or branched C 2 -C, g alkenyl groups; linear or branched C 2 -C 18 alkinyl groups, OH groups, NH groups , SH groups . Examples of Cι-C 18 alkyl groups are: methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, t-butyl, t-amyl, 2-ethylhexyl, n-octyl, 1, 1, 3 , 3-tetramethylbutyl, n-do- decyl, 1, 1, 7, 7-tetramethyloctyl, n-octadecyl , etc. Examples of C 2 -C 18 alkenyl groups are: vinyl, propylene, butylene, pentylene, hexylene, etc. Examples of C 2 -C 18 alkinyl groups are: acetylene, propyne, butyne, 2-butyne, etc. Examples of C 5 -C 18 cycloalkyl groups, optionally substituted, are: cyclohexyl, cyclopentyl, methylcyclo- hexyl, etc. Examples of C 7 -C 15 arylalkyl or alkylaryl groups are: benzyl, 2-phenylethyl, 4-t-butylbenzyl, etc. Examples of C 6 -C 14 aryl groups, optionally substituted, are: phenyl, naphthyl, anthracenyl, 2-hydroxy- phenyl, etc. Examples of C j -C.^ alkoxyl groups are: methoxyl, ethoxyl, propoxyl, n-butoxyl, etc. Examples of heterocyclic groups with 5 or 6 atoms, optionally substituted, are: piperidine, morpholine, piperazine, triazole, tetrameth lpiperidine, pentame- thylpiperidine, tetramethylmorpholine, pentamethylmor- pholine, 4-hydroxy-tetramethylpiperidine, etc. Specific examples of compounds having general formula (I) , which in no way limit the scope of the present invention, are: The compounds having general formula (I) of the present invention can be prepared with various processes . A further object of the present invention relates to a process for the preparation of 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (I). A process for the preparation of compounds having general formula (I) comprises: (a) reacting a 2- (2 ' hydroxyphenyl) benzotriazole having general formula (IX) : wherein X and R have the same meanings defined above, with a secondary amine having general formula (X) : \ N—H (X) wherein R 7 and R 8 , the same or different, preferably the same, represent a linear alkyl group having from 3 or more carbon atoms, in the presence of formaldehyde or para-formaldehyde, preferably para- formaldehyde and an inert organic solvent such as, for example, an alcohol, preferably n-butanol, at a temperature ranging from 95 °C to 100 °C, for a time ranging from 40 hours to 60 hours, obtaining the Mannich base having general formula (XI) : wherein R, R 7 and R 8 have the same meanings defined above; (b) reacting the Mannich base having general formula (XI) obtained in step (a) with a 2 , 4-imidazolidinedione having general formula (XII) : wherein Ri, R 2 and R 3 have the same meanings de- scribed above, in the presence of an alkaline catalyst such as, for example, sodium methylate, sodium hydroxide, potassium hydroxide, lithium hydroxide, etc., and an inert organic solvent having a boiling point at 160 °C such as, for example, 1 , 2 , 4 -trimethylbenzene, 4-isopropyl- benzene, etc., at a temperature ranging from 20°C to 200°C, preferably between 40°C and 170°C, for a time ranging from 20 hours to 30 hours, obtaining a solution from which, after cooling to room temperature and eliminating the catalyst by filtration and the solvent by evaporation, the desired compound is isolated by crystallization in the presence of an inert organic solvent selected from alcohols (for example, methanol, etc.); monoalkylethers (for example, 2-me hoxyethanol, etc.); linear or cyclic aliphatic hydrocarbons (for example, hexane, heptane, cyclohexane, methylcyclohexane, etc.); aromatic hydrocarbons (for example, toluene, etc.) ; chlorinated aromatic solvents (for example, chlorobenzene, etc.). The 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (IX) can be prepared as described, for example, in German patent application DE 4.237.817. The secondary amines having general formula (X) and 2 , 4-imidazolidinediones having general formula (XII), are commercially available compounds. As " already mentioned above, the compounds having general formula (I) of the present invention can be used as light stabilizers for a wide range of organic polymers. Organic polymers capable of being stabilized with the compounds of the present invention are: (1) polymers of mono-olefins and diolefins such as, for example, polypropylene, polyisobutylene, polybut-1-ene, poly-4-methylpent-l-ene, polyiso- prene or polybutadiene; as well as polymers of cyclo-olefins such as, for example, cyclopentene or norbornene; polyethylene (which can be optionally cross-linked) such as, for example, high density polyethylene (HDPE) , low density polyethylene (LDPE) , linear low density polyethylene (LLDPE) , branched low density polyethylene (BLDPE) . Polyolefins such as, for example the monolefins mentioned in the above paragraph, preferably polyethylene and polypropylene, can be prepared with various methods known in literature, preferably using the following methods : (a) radicalic polymerization (generally carried out at a high pressure and high temperature) ; (b) catalytic polymerization using a catalyst which normally contains one or more metals of groups IVb, Vb, VIb or VIII of Periodic Table. These metals generally have one or more ligands such as, for example, oxides, halides, alcoholates, ethers, amines, alkyls, alkenyls and/or aryls which can be ix- or σ-co-ordinated. These metal complexes can be in free form or supported in substrates such as, for example activated magnesium chloride, titani- um(III) chloride, alumina or silicon oxide. These catalysts can be soluble or insoluble in the reaction medium. The catalysts can be used alone or in the presence of other activators such as, for example, metal alkyls, metal hydrides, halides of metal alkyls, oxides of metal alkyls or metal alkyloxanes, these metals being elements belonging to groups la, Ila and/or Ilia of the Periodic Table. The activators can be conveniently modified with other ester, ether, amine or silyl -ether groups. These catalytic systems are usually called Phillips, Standard Oil Indiana, Ziegler (-Natta) , TNZ (Du-Pont) , metallocene or "single site catalyst" (SSC) . (2) Mixtures of the polymers described under point (1) such as, for example, mixtures of polypropylene with polyisobutylene; mixtures of polypropylene with polyethylene (for example, PP/HDPE, PP/ DPE) ; mixtures of different types of polyethylene (for example, DPE/HDPE) . (3) Copolymers of mono-olefins and diolefins with each other or with other vinyl monomers such as, for example, ethylene-propylene copolymers, linear low density polyethylene (LLDPE) and its mixtures with low density polyethylene (LDPE) , propylene/but-1- ene copolymers, propylene/isobutylene copolymers, ethylene/but-1-ene copolymers, ethylene/hexene copolymers, ethylene/methylpentene copolymers, ethylene/heptene copolymers, ethylene/octene copolymers, propylene/butadiene copolymers, isobutylene/isoprene copolymers, ethylene/alkyl acrylate copolymers, ethylene/alkyl methacrylate copolymers, ethylene/vinyl acetate copolymers and their copolymers with carbon monoxide or ethyl - ene/acrylic acid copolymers and their salts (ionomers) as well as terpolymers of ethylene with polypropylene and a diene such as, for example, hexadiene, dicyclopentadiene or ethylidene-norbor- nene; and mixtures of these copolymers with each other or with the polymers cited in paragraph (1) such as, for example, polypropylene/ethylene- propylene copolymers, LDPE/ethylene-vinylacetate (EVA) copolymers, LDPE/ethylene-acrylic acid (EAA) copolymers, LLDPE/EVA, LLDPE/EAA, and alternating or "random" polyalkylene/carbon monoxide copoly- mers and their mixtures with other polymers such as, for example, polyamides . (4) Hydrocarbon resins (for example, C 5 -C 9 ) comprising their hydrogenated modifications (for example, adhesive agents) and mixtures with polyalkylene and starch. (5) Polystyrene, poly (p-methylstyrene) , poly (α-methyl- styrene) . (6) Copolymers of styrene or a-methylstyrene with dienes or acrylic derivatives such as, for exam- pie, styrene/butadiene, styrene/acrylonitrile, styrene/alkyl methacrylate, styrene/butadiene/ alkyl acrylate, styrene/butadiene/alkyl methacrylate, styrene/maleic anhydride, styrene/acrylo- nitrile/methylacrylate; mixtures, having a high impact strength, between copolymers of styrene and another polymer such as, for example, a polyacry- late, a polymer of a diene or an ethylene/propyl- ene/diene terpolymer, block polymers of styrene such as, for example, styrene/butadiene/styrene, styrene/isσprene/styrene, styrene/ethylene/bu- tylene/styrene or styrene/ethylene/propylene/ styrene. (7) Grafted copolymers of styrene or a-methylstyrene such as, for example, styrene in polybutadiene, styrene in polybutadiene or polybutadiene-acrylo- 093 nitrile copolymers; styrene and acrylonitrile (or methacrylonitrile) in polybutadiene; styrene, acrylonitrile and methylmethacrylate in polybutadiene; styrene and maleic anhydride in polybuta- diene; styrene, acrylonitrile and maleic anhydride or maleimide in polybutadiene; styrene and maleimide in polybutadiene; styrene and alkylacrylates or methacrylates in polybutadiene; styrene and acrylonitrile in ethylene/propylene/diene terpoly- mers, styrene and acrylonitrile in polyalkyl acrylates or polyalkyl methacrylates, styrene and acrylonitrile in acrylate/butadiene copolymers, as well as mixtures of the copolymers listed above with the copolymers cited under point (6) such as, for example, mixtures of known copolymers such as ABS, MBS, ASA or AES ; (8) Polymers containing halogens such as, for example, polychloroprene, chlorinated rubbers, chlorinated or chlorosulfonated polyethylene, ethylene and chlorinated ethylene copolymers, homopolymers and copolymers of epichlorohydrin, in particular polymers of vinyl compounds containing halogens such as, for example, polyvinyl chloride, poly- vinylidenechloride, polyvinyl fluoride or polyvin- ylidenefluoride; and also their copolymers such 093 as, for example, vinyl chloride/vinylidenechlo- ride, vinyl chloride/vinyl acetate or vinylidene- chloride/vinyl acetate. (9) Polymers deriving from c_,/3-unsaturated acids and their derivatives such as, for example, polyacry- lates and polymethacrylates, polymethyl methacrylates, polyacrylamides and polyacrylonitriles, modified with butyl acrylate. (10) Copolymers of monomers according to point (9) with each other or with other unsaturated monomers such as, for example, acrylonitrile/butadiene copolymers, acrylonitrile/alkylacrylate copolymers, acrylonitrile/alkoxyalkyl acrylate copolymers or acrylonitrile/vinyl halide copolymers or acryloni- trile/alkyl methacrylate/butadiene terpolymers. (11) Polymers deriving from unsaturated alcohols and amines, or their acyl or acetal derivatives such as, for example, polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyrral, polyallyl phthalate or polyallyl melamine; and also their copolymers with the olefins listed under point (1) . (12) Homopolymers and copolymers of open-chain ethers or cyclic ethers such as, for example, polyalkyle- 093 ne glycols, polyethyleneoxide, polypropylene oxide, or copolymers of the compounds described above with bis-glycidyl ethers. (13) Polyacetals such as, for example, polyoxymethylene and polyoxymethylenes which contain ethylene oxide as comonomer; polyacetals modified with thermoplastic polyurethanes, acrylates or MBS. (14) Polyphenylene oxides and sulfides and mixtures of polyphenylene oxides with styrene or polyamide polymers. (15) Polyurethanes deriving from hydroxyl-terminated polyethers, polyesters or polybutadienes on the one hand and aliphatic or aromatic polyisocyanates on the other, as well as the precursors of the above compounds . (16) Polyamides and copolyamides deriving from diamines and dicarboxylic acids and/or aminocarboxylic acids or from the corresponding lactams such as, for example, polyamide 4, polyamide 6, polyamide 6/6 , 6/10, 6/9, 6/12, 4/6, 12/12, polyamide 11, polyamide 12, aromatic polyamides obtained starting from m-xylene diamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic and/or terephthalic acid and with or without an elastomer as modifier, for example, 93 poly-2, 4, 4-trimethylhexamethylene terephthalamide or poly-m-phenylene isophthalamide; and also block copolymers of the above polyamides with poly- olefins, olefinic copolymers, ionomers or elasto- mers chemically bound or grafted; or with polye- thers such as, for example, polyethylene glycol, polypropylene glycol or polytetramethylene glycol; as well as polyamides or copolyamides modified with EPDM or ABS; and polyamides condensed during processing ("RIM polyamide system"). (17) Polyureas, polyimides, polyamide-imides and polybenzoimidazoles . (18) Polyesters deriving from dicarboxylic acids and diols and/or from hydroxycarboxylic acids or from the corresponding lactones such as, for example, polyethylene terephthalate, polybutylene tereph- thalate, poly-1, 4-dimethylolcyclohexane terephthalate and polyhydroxybenzoates, as well as block cσpolyether esters deriving from polyethers with hydroxyl-terminated groups; and also polyesters modified with polycarbonates or MBS. (19) Polycarbonates and polyester carbonates. (20) Polysulfones, polyethersulfones and polyetherketo- nes . (21) Cross-linked polymers deriving from aldehydes on 3 the one hand and from phenols, urea and melamines on the other, such as, for example, phenol/formaldehyde resins, urea/formaldehyde resins and melamine/formaldehyde resins. (22) Drying or non-drying alkyd resins. (23) Resins based on unsaturated polyesters deriving from copolyesters of dicarboxyl acids saturated and unsaturated with polyhydric alcohols and vinyl compounds as cross-linking agents, and also the above resins containing halogens and having a good flame-resistance . (24) Cross-linkable acrylic resins deriving from substituted acrylates such as, for example, epoxy acrylates, urethane acrylates or polyester acryla- tes. (25) Alkyd resins, resins based on polyesters or acrylated resins cross-linked with melamine resins, urea resins, resins based on polyisocyana- tes or epoxy resins . (26) Cross-linked epoxy resins deriving from polyepoxi- des such as, for example, bis-glycidyl ethers or cycloaliphatic diepoxides. (27) Natural polymers such as, for example, cellulose, rubber, gelatine, and their derivatives chemically modified to give homologous polymers such as, for 93 example, cellulose acetates, propionates and butyrates, or cellulose ethers such as, for example, methyl-cellulose; as well as hydrocarbon resins ("rosins") or their derivatives. (28) Mixtures of the above polymers ("polyblends") such as, for example, PP/EPDM, polyamides/EPDM or ABS, PVC/EVA, PVC/ABS, PVC/MBS, PC/ABS, PBTP/ABS, PC/ASA, PC/PBT, PVC/CPE, PVC/acrylates , POM/ther- moplastics PUR, PC/thermoplastics PUR, POM/acryla- tes, POM/MBS, PPO/HIPS, PPO/PA 6 . 6 and copolymers, PA/HDPE, PA/PP, PA/PPO. The compounds having formula (I) of the present invention are particularly useful in the stabilization of polycarbonates . A further object of the present invention relates to polymeric compositions containing an organic polymer and an effective quantity of one or more compounds having general formula (I) . The compounds having general formula (I) of the present invention can be used as such or combined with other stabilizers, in the above polymeric compositions. In- general, the above compounds having general formula (I) are used in a quantity ranging from about 0.1% to about 5% by weight of the weight of the poly- meric compositions to be stabilized, although the 093 quantity used varies according to the substrate to be stabilized and the final application. They are preferably added in a quantity ranging from about 0.5% to about 3% by weight of the weight of the polymeric compositions to be stabilized. The compounds having general formula (I) , optionally in the presence of other additives, can be easily incorporated in the organic polymers to be stabilized using the conventional techniques. This incorporation can take place before or during the formation of the end-product, for example, by mixing the compounds having general formula (I) in powder form with the polymer to be stabilized, or by adding these compounds to the polymer to be stabilized in the molten state or in solution, or applying a solution or suspension of these compounds to the polymer to be stabilized, optionally evaporating the solvent used. The elastomers can be stabilized as latexes. Another method for incorporating the compounds having general formula (I) in the organic polymers comprises the addition of these before or during the polymerization of the corresponding monomers or before the cross- linking. The compounds having general formula (I) or their mixtures, can be added to the polymer to be stabilized 93 also in masterbatch form which comprises these compounds in a concentration ranging, for example, from 2.5% to 25% by weight. The compounds having general formula (I) can be conveniently incorporated in the organic polymers to be stabilized by means of the following methods: in the form of emulsion or suspension (for example, in the case of latexes or polymers in emulsion) ; - as a mixture of powders in the case of the conventional addition of additional compounds or mixtures of organic polymers; directly adding to the apparatus used for processing the organic polymers (for example, extruders, internal mixers, etc.); in the form of solution or molten product. The polymeric compositions stabilized as said above can be converted to end-products such as, for example, fibers, films, tapes, sheets, multi-layer sheets, containers, tubes and other forms, by means of methods known in the art such as, for example, casting, hot moulding, spinning, extrusion or injection moulding. The present invention therefore also relates to the use of the above polymeric compositions for the production of end-products. 93 The use of multi-layer systems is also of interest, in which one of the above compositions having a relatively high content of a compound having general formula (I) , for example, between 5% and 15% by weight, is applied in the form of a thin film (10-100 μm in thickness) to a shaped article consisting of a polymer not containing or containing a small quantity of a compound having general formula (I) . This application can be carried out during the formation of said arti- cle, for example, by means of a co-extrusion. The application can also be effected however on the end shaped-article, for example, by lamination with a film or by coating with a solution. The surface layer or layers of the end-article act as a UV filter which protects the inside of the articles from the deteriorating action of UV light. The upper layer preferably contains from 5% to 15% by weight, more preferably from 5% to 10% by weight, of at least one compound having general formula (I) . The use of the above compositions for the production of multi-layer systems, in which the upper layer having -a thickness of 10-100 μm comprises these compositions, whereas the internal layer does not contain or contains a small quantity of a compound having general formula (I) consequently represents a further object of 093 the present invention. The polymers stabilized as described above have a high resistance to degradation caused by atmospheric agents, in particular a high resistance to UV light. They are therefore capable of maintaining their colour and brightness for a long period even when exposed to external agents . The compositions described above can also be used as compositions for coating or painting ("coating compositions") such as, for example, paints, lacquers, plastic-based compositions. For the purposes of the present invention, coating or painting compositions are preferred in which the organic polymer is selected from: (a) a thermoplastic polymer selected from thermoplastic polymers containing heteroatoms, in particular nitrogen, sulfur and/or oxygen, in the main chain, styrene copolymers, grafted styrene polymers and polymethyl methacrylates (PMMA) ; or (b) a paint ligand. Specific examples of thermoplastic polymers (a) containing heteroatoms, in particular nitrogen, sulfur and/or oxygen, in the main chain, are listed above under points 13 to 20. Among these, polycarbonates, polyesters, polyamides, polyacetals, polyphenylene oxides and polyphenylene sulfides are preferred; particularly preferred are polycarbonates, polyesters such as, for example, polyethylene terephthalate (PET) , and polyamides (PA) such as, for example, PA 6 and PA 6/6; even more preferred are polycarbonates. Specific examples of styrene copolymers and grafted styrene polymers (a) are listed above under points 6 and 7. Paint ligands (b) can comprise at least one of the organic polymers specified herebelow. Specific examples of paints containing specific ligands are: 1. paints based on alkyd resins, acrylic resins, polyester resins, epoxy resins or melamine resins, which can be cross-linked at a low or high temper- ature, or mixtures of these resins, to which a cross-linking agent is optionally added; 2. polyurethane paints with two components based on acrylic resins containing hydroxyl groups, polyester resins or polyether resins and aliphatic or aromatic isocyanates, isocyanurates or polyisocya- nates; 3. polyurethane paints with one component based on block isocyanates, isocyanurates or polyisocyana- tes which are unblocked during oven treatment; 4. paints with two components based on (poly)ketoi- 3 mines and aliphatic or aromatic isocyanates, isocyanurates or polyisocyanates; 5. paints with two components based on (poly)keto- imines and an unsaturated acrylic resin or a polyacetoacetate resin or a methyl methalcry- lamidoglycolate; 6. paints with two components based on polyacrylates containing a carboxylic group or an amine group and polyepoxides; 7. paints with two components based on acrylic resins containing an anhydride group and a polyhydroxyl or polyamine compound; 8. paints with two components based on (poly) -oxazo- line and acrylic resins containing an anhydride group or unsaturated acrylic resins or aliphatic or aromatic isocyanates, or isocyanurates or polyisocyanates; 9. paints with two components based on unsaturated polyacrylates and polymalonates; 10. thermoplastic polyacrylic paints based on thermoplastic acrylic resins or non-self-crosslinking acrylic resins combined with etherified melamine resins; 11. systems for paints based on siloxane-modified acrylic resins; 12. systems for paints based on fluoro-modified acrylic resins; and 13. systems for paints based on allyl glycidyl ethers. The paints can be applied as one or two layers of coating ("one- or two-coat") and the stabilizing compounds having formula (I) are preferably added to the upper colourless coating. The paints can be applied to the substrate (metal, plastic, wood, etc.) using the conventional methods such as, for example, brushing, spraying, pouring, dipping or electrophoresis . A preferred embodiment of the present invention consists in paints or coatings (for example car coatings) comprising at least one compound having general formula (I) . Ligands which can be used for the purpose are, for example, those listed above. The compounds having general formula (I) of the present invention can be combined, as already mentioned above, with other conventional additives or their mixtures. These additives are added in a quantity ranging -from about 0.1% to about 5% by weight of the weight of the polymeric compositions to be stabilized, preferably from about 0.5% to about 3% by weight. Some of the additives used are listed below as an example. 1. Antioxidants 1.1 Alkylated monophenols such as, for example: 2 , 6-di-t-butyl-4-methylphenol ; 2-t-butyl-4 , 6-dimethylphenol; 2 , 6-di-t-butyl-4-ethylphenol; 2, 6-di-t-butyl-4-n-butylphenol; 2 , 6-di-t-butyl-4-isobutylphenol ; 2 , 6-di-cyclopentyl-4-methylphenol ; 2- (o_-methylcyclohexyl) -4, 6-dime hylphenol; 2 , 6-dioctadecyl-4-methylphenol; 2,4, 6-tricyclohexylphenol; 2 , 6-di-t-butyl-4-methoxymethylphenol; 2 , 6-di-nonyl-4-methylphenol; 2 , 4-dimethyl-6- (1 ' -methylundec-1 ' -yl) phenol ; 2,4-dimethyl-6- (1 'methylhectadec-1 ' -yl) phenol; 2 ,4 -dimethyl -6- (1 ' -methyltridec-1 ' -yl) phenol; and their mixtures . 1.2 Alkylthiomethylphenols such as, for example: 2 , 4-dioctylthiomethyl-6-t-butylphenol ; 2 , 4-dioctylthiomethyl-6-methylphenol ; 2 , 4-dioctylthiomethyl-6-ethylphenol ; 2 , 6-didodecylthiomethyl-4-nonylphenol . 1.3 Hydroquinones and alkylated hydroquinones such as, for example : 2 , 6-di-t-butyl-4-methoxyphenol ; 2, 5-di-t-butylhydroquinone; 2 , 5-di-t-amylhydroquinone; 2 , 6-diphenyl-4-octadecyloxyphenol; 2 , 6-di-t-butylhydroquinone; 2 , 5-di-t-butyl-4-hydroxyanisol; 3 , 5-di-t-butyl-4-hydroxyanisol; 3, 5-di-t-butyl-4 -hydroxyphenyl stearate; bis(3,5-di-t-butyl- -hydroxyphenyl) adipate . 1.4 Tocopherols such as, for example: c.-tocopherol, β -tocopherol , γ-tocopherol, δ-tocopherol and their mixtures (Vitamin E) . 1.5 Hydroxylated thiophenyl ethers such as, for example : 2,2' -thiobis- (6-t-butyl-4-methylphenol) ; 2,2 ' -thiobis- (4 -octylphenol) ; 4,4' -thiobis- (6-t-butyl-3-methylphenol) ; 4,4' -thiobis- (6-t-butyl-2-methylphenol) ; 4,4' -thiobis- (3 , 6-di-sec-amylphenol) ; 4,4 ' -bis- (2, 6-dimethyl-4 -hydroxyphenyl) disulfide. 1.6 Alkylidene-bisphenols such as, for example: 2,2' -methylenebis- (6-t-butyl-4-methylphenol) ; 2,2' -methylenebis- (6-t-butyl-4-ethylphenol) ; 2,2' -methylenebis [4-methyl-6- (c_-methylcyclohexyl) - phenol] ; 2,2 ' -methylenebis (4-methyl-6-cyclohexylphenol) ; 2,2 ' -methylenebis (6-nonyl-4-methylphenol) ; 2,2' -methylenebis (4 , 6-di-t-butylphenol) ; 2,2' -ethylidenebis (4, 6-di-t-butylphenol) ; 2,2' -ethylidenebis (6-t-butyl-4-isobutylphenol) ; 2,2 ' -methylenebis [6- (of-methylbenzyl) -4-nonylphe- nol] ; 2,2 ' -methylenebis [6- (c_, c_-dime hylbenzyl) -4-nonyl- phenol] ; 4,4' -methylenebis (2, 6-di-t-butylphenol) ; 4, 4 ' -methylenebis (6-t-butyl-2-methylphenol) ; 1, 1-bis- (5-t-butyl-4-hydroxy-2 -methylphenyl ) - butane; 2 , 6-bis- (3-t-butyl-5-methyl-2-hydroxybenzyl) -4- methylphenol ; 1,1, 3-tris- (5-t-butyl-4-hydroxy-2-methylphenyl) - butane; 1, 1-bis- (5-t-butyl-4-hydroxy-2-methyl-phenyl) -3-n- dodecylmercaptobutane; ethyleneglycol bis [3 , 3 -bis (3 ' -t-butyl-4 ' -hydroxy- phenyl) butyrate] ; bis (3-t-butyl-4-hydroxy-5-methylphenyl) dicyclopen- tadiene; bis [2- (3 ' -t-butyl-2 ' -hydroxy-5 ' -methylbenzyl) -6-t- butyl- 4 -methylphenyl] terephthalate; 1, 1-bis (3 , 5 -dimethyl -2 -hydroxyphenyl) butane ; 2 , 2-bis (3 , 5-di- -butyl-4 -hydroxyphenyl) propane; 2 , 2-bis (5-t-butyl -4 -hydroxy-2 -methylphenyl) -4-n- dodecylmercaptobutane ; 1,1,5, 5-tetra(5-t-butyl-4-hydroxy-2-methylphenyl) - pentane . 1.7 Benzyl compounds containing 0, N or S such as, for example : 3 , 5 , 3 ' , 5 ' -tetra-t-butyl-4 , 4 ' -dihydroxydibenzyl ether; octadecyl -4 -hydroxy- 3 , 5-dimethylbenzylmercapto- acetate; tris (3 , 5-di-t-butyl-4-hydroxybenzyl) amine; bis (4-t-butyl-3-hydroxy-2 , 6-dime hylbenzyl) dithio- terephthalate ; bis (3 , 5-di-t-butyl-4-hydroxybenzyl) sulfide; iso-octyl -3 , 5 -di -t-butyl-4 -hydroxybenzyl ercapto- acetate; 1.8 Hydroxybenzylated malonates such as, for example: dioctadecyl-2 , 2-bis (3 , 5-di-t-butyl-2-hydroxyben- zyl) malonate; dioctadecyl-2- (3 -t-butyl-4 -hydroxy -5 -me thylben- zyl) malonate; didodecylmercaptoethyl-2 , 2-bis (3 , 5-di-t-butyl-4- hydroxybenzyl ) malonate ; bis [4- (l,l,3, 3 -tetrame thylbutyl ) phenyl] -2,2- bis (3 , 5-di- -butyl-4 -hydroxybenzyl) malonate. 1.9 Aromatic hydroxybenzyl compounds such as, for example : 1,3, 5-tris (3 , 5 -di -t-butyl-4 -hydroxybenzyl) -2,4,6- trimethylbenzene; 1,4-bis- (3, 5-di-t-butyl-4-hydroxybenzyl) -2,3,5,6- tetramethylbenzene ; 2,4, 6-tris (3, 5 -di-t-butyl-4-hydroxybenzyl) phenol . 1.10 Triazine compounds such as, for example: 2,4-bis (octylmercapto) -6- (3, 5-di-t-butyl-4-hydro- xyaniline) -1,3, 5-triazine; 2 -octylmercapto-4, 6-bis (3 , 5 -di-t-butyl-4-hydro- xyaniline) -1,3, 5-triazine; 2 -octylmercapto-4, 6 -bis (3 , 5 -di-t-butyl-4 -hydro- xyphenoxy) -1, 3 , 5-triazine; 2, 4, 6-tris- (3, 5 -di- 1 -butyl -4 -hydroxyphenoxy) - 1,2, 3 -triazine ; 1,3, 5-tris (3, 5-di-t-butyl-4-hydroxybenzyl) isocya- nurate; 1,3, 5-tris (4 -t -butyl -3 -hydroxy-2 , 6-dimethylben- zyl) isocyanurate; 2,4, 6-tris- (3 , 5-di-t-butyl-4-hydroxyphenylethyl) - 1,3, 5-triazine; 1 , 3 , 5 -tris ( 3 , 5 -di -t -butyl -4 -hydroxyphenylpropio- nyl ) hexahydro- 1 , 3 , 5 -triazine ; 1,3, 5-tris- (3, 5-dicyclohexyl -4 -hydroxybenzyl) isocyanurate . 1.11 Benzylphosphonates such as, for example: dimethyl -2,5-di-t- butyl - 4 - hydroxybenzylphosphona - te; diethyl-3 , 5-di-t-butyl-4-hydroxybenzylphosphonate; dioctadecyl-3 , 5-di-t-butyi-4-hydroxybenzylphospho- nate; dioctadecyl-5-t-butyl-4 -hydroxy-3-methylbenzylpho- sphonate; calcium salts of monoethyl ester of 3,5-di-t- butyl-4-hydroxybenzylphosphonic acid. 1.12 Acylaminophenols such as, for example: 4-hydroxylauranilide ; 4 -hydroxystearanilide; octyl-N- (3, 5-di-t-butyl-4-hydroxyphenyl) carbamate. 1.13 Esters of β- (3 , 5-di-t-butyl-4 -hydroxyphenyl) pro- pionic acid with monohydric or polyhydric alcohols such as, for example: methanol, ethanol , octanol , octadecanol, 1,6-he- xandiol, 1, 9-nonandiol, ethylene glycol, 1,2-pro- panediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaeryth- ritol, tris (hydroxyethyl) isocyanurate, N,N'- bis (hydroxyethyl) oxamide, 3-thioundecanol , 3- thiopentadecanol , trimethylhexandiol , trimethyl- olpropane, 4-hydroxymethyl-l-phospho-2 , 6, 7-trioxa- bicyclo[2.2. 2] octane. 1.14 Esters of β- (5 -t-butyl-4 -hydroxy-3-methylphe- nyl) propionic acid with monohydric or polyhydric alcohols such as, for example: methanol, ethanol, octanol, octadecanol, 1,6- hexandiol, 1, 9-nonandiol, ethylene glycol, 1,2- propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N,N' -bis (hydroxyethyl) oxamide, 3-thioundecanol, 3- thiopentadecanol, trimethylhexandiol, trimethylol- propane, 4-hydroxymethyl-1-phospho-2,6,7-trioxabi- cyclo [2.2.2] octane. 1.15 Esters of β- (3 , 5-dicyclohexyl -4-hydroxyphenyl) propionic acid with monohydric or polyhydric alcohols such as, for example: methanol, ethanol, octanol, octadecanol, 1,6- hexandiol, 1, 9-nonandiol, ethylene glycol, 1,2- propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N,N' -bis (hydroxyethyl) oxamide, 3-thioundecanol, 3- thiopentadecanol, trimethylhexandiol, trimethylol- propane, 4-hydroxymethyl-l-phospho-2, 6, 7-trioxabi- cyclo [2.2.2] octane. 1.16 Esters of (3 , 5 -di-t -butyl -4 -hydroxyphenyl) acetic acid with monohydric or polyhydric alcohols such as , for example : methanol, ethanol, octanol, octadecanol, 1,6- hexandiol, 1, 9-nonandiol , ethylene glycol, 1,2- propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, N,N' -bis (hydroxyethyl) oxamide, 3-thioundecanol, 3- thiopentadecanol, trimethylhexandiol, trimethylol- propane, 4-hydroxymethyl-l-phospho-2, 6, 7-trioxabi- cyclo [2.2.2] octane . 1.17 Amides of β- (3 , 5-di-t-butyl-4 -hydroxyphenyl) - propionic acid such as, for example: N,N' -bis (3 , 5-di-t-butyl-4-hydroxyphenylpropio- nyl ) hexamethylenediamine ; N,N' -bis (3 , 5-di-t-butyl-4-hydroxyphenylpropio- nyl) trimethylenediamine; N,N' -bis (3 , 5-di-t-butyl-4-hydroxyphenylpropio- nyl ) hydrazine . 2. Ultra-violet ray and light stabilizers. 2.1 Derivatives of 2- (2 ' -hydroxyphenyl) benzotriazoles such as, for example: 2- (2 ' -hydroxy-5 ^-methylphenyl) benzotriazole; 2- (3 ' , 5 ' -di-t -butyl -2 ' -hydroxyphenyl) benzotriazole; 2- (5 ' -t-butyl-2 ' -hydroxyphenyl) benzotriazole; 2- [2 ■ -hydroxy-5 '-(1,1,3, 3 -tetramethylbutyl) phenyl] benzotriazole; 2- (3 ' , 5 ' -di-t-butyl-2 ' -hydroxyphenyl) -5-chlorobenzotriazole; 2 - (3 ' -t-butyl-2 ' -hydroxy-5 ' -methylphenyl) -5- chlorobenzotriazole; 2- (3 ' -sec-butyl-5 ' -t-butyl-2 ' -hydroxyphenyl) benzotriazole ; 2- (2 ' -hydroxy-4 ' -octyloxyphenyl) -benzotriazole; 2- (3 ' , 5 ' -di-t-amyl-2 ' -hydroxyphenyl) -benzotriazo- le; 2 - [3 ' , 5 ' -bis (α, α-dimethylbenzyl) -2 ' -hydroxyphenyl ] benzotriazole ; mixtures of 2- [3 ' -t-butyl-2 ' -hydroxy-5 ' - (2-octylo- xycarbonylethyl) phenyl) -5-chorobenzotriazole, 2- [3 ' -t-butyl-5 ' - (2- (2-ethylhexyloxy) carbonylethyl) - 2 ' -hydroxyphenyl] -5-chlorobenzotriazole, 2- [3 ' -t- butyl-2 ' -hydroxy-5 ' - (2 -methoxycarbonylethyl) phenyl] -5-chlorobenzotriazole, 2- [3 ' -t-butyl-2 ' - hydroxy-5 ' - (2 -methoxycarbonylethyl) phenyl] benzo- triazole, 2- [3 ' -t-butyl-2 ' -hydroxy-5 '- (2 -octylo- xycarbonylethyl) phenyl] benzotriazole, 2- [3 ' -t- butyl-5 ' - (2- (2-ethylhexyloxy) carbonylethyl) -2 ' - hydroxyphenyl) benzotriazole, 2- (3 ' -dodecyl-2 ' - hydroxy-5 ' -methylphenyl) benzotriazole and 2 - [3 ' -t- butyl-2 ' -hydroxy-5 ' - (2 - iso-octyloxycarbonyl - ethyl) phenyl] benzotriazole, 2,2' -methylene-bis [4- (1,1,3,3 -tetramethylbutyl) -6-benzotriazol-2-yl- phenol] ; esterification product of 2- [3 ' -t-butyl- 5 ' - (2 -methoxycarbonylethyl) -2 ' -hydroxyphenyl] -2H- benzotriazole with polyethylene glycol 300; [R-CH 2 CH 2 -COO(CH 2 ) 3 ] 2 wherein R = 3 ' -t-butyl-4- hydroxy-5 ' -2H-benzotriazol-2 -yl -phenyl . 2.2 Derivatives of 2-hydroxybenzophenones such as, for example: 4-hydroxy-; 4-methoxy-; 4-octyloxy- ; 4- decyloxy- ; 4-dodecyloxy- ; 4-benzyloxy- ; 4,2 ',4'- trihydroxy- ; 2 ' -hydroxy-4 , 4 ' -dimethoxy. 2.3 Esters of benzoic acids, optionally substituted, such as, for example: phenyl salicylate, 4-t- butylphenyl salicylate, octylphenyl salicylate, benzoyl-resorcinol, bis (4-t-butylbenzoyl) -resor- cinol, dibenzoyl-resorcinol, 2 , 4-di-t-butylphenyl- 3 , 5-di-t-butyl-4-hydroxybenzoate, hexadecyl-3 , 5- di-t-butyl-4-hydroxybenzoate, octadecyl-3 , 5-di-t- butyl-4-hydroxybenzoate, 2 -methyl-4 , 6-di-t-butyl- phenyl-3 , 5-di-t-butyl-4-hydroxybenzoate . 2.4 Acrylates such as, for example, ethyl or isoctyl α-cyano-jS, jS-diphenylacrylate; methyl c_-carbometho- xycinnamate, methyl or butyl α-cyano-jS-methyl-p- methoxycinnamate, methyl α-carbomethoxy-p-methoxy- cinnamate, N- (/3-carbomethoxy-/3-cyanovinyl) -2- methylindoline . 2.5 Nickel compounds such as, for example, complexes of 2,2 ' -thio-bis- [4- (1, 1, 3 , 3-tetramethylbutyl) phenol] , for example 1:1 or 1:2 complexes, with or without additional ligands such as n-butylamine, triethanolamine or N-cyclohexyldiethanolamine, nickel dibutyldithiocarbamate, nickel salts of monoalkyl esters of 4-hydroxy-3 , 5-di-t-butyl- benzyl-phosphonic acid, such as methyl or ethyl esters, nickel complexes with ketoximes such as 2- hydroxy-4 -methylphenyl undecyl ketoxime, nickel complexes of l-phenyl-4-lauroyl-5-hydroxypyrazol with or without additional ligands. 2.6 Sterically hindered amines such as, for example: bis (2,2,6, 6-tetramethyl-piperidyl) sebacate; bis (2,2,6, 6-tetramethyl-piperidyl) succinate; poly-methylpropyl-3-oxy [4- (2,2,6, 6-tetramethyl) pi- peridinyl] siloxane; bis (1,2,2,6, 6-pentamethyl-piperidyl) sebacate; bis (1, 2 , 2 , 6, 6-pentamethyl-piperidyl) n-butyl-3 , 5- di- t-butyl-4 -hydroxybenzylmalonate; condensation product between 1- (2 -hydroxyethyl ) - 2 , 2 , 6, 6-tetra-4-hydroxypiperidine and succinic acid; condensation product between N,N' -bis (2, 2 , 6, 6- tetramethyl-4-piperidyl) hexamethylenediamine and 4-t-octylamino-2 , 6-dichloro-l, 3 , 5-triazine; tris (2,2,6, 6-tetramethyl-4 -piperidyl) nitrilotri- acetate; tetrakis (2,2,6, 6-tetramethyl-4-piperidyl) -1,2,3,4- butane-tetracarboxylate; 1, 1 ' - (1, 2-ethanodiyl) bis (3 , 3 , 5 , 5 -tetramethyl - piperazinone ; 4-benzoyl-2 ,2,6, 6-tetramethylpiperidine; 4-stearyloxy-2 ,2,6, 6-tetramethylpiperidine; bis (1, 2 , 2 , 6, 6-pentamethylpiperidyl) -2-n-butyl-2- (2-hydroxy-3 , 5-di-t-butylbenzyl) malonate; 3-n-octyl-7, 7,9, 9- tetramethyl - 1 , 3 , 8-triazaspi- ro [4.5] decan-2 ,4-dione; bis (l-octyloxy-2 ,2,6, 6-tetramethylpiperidyl) sebacate; bis (l-octyloxy-2 ,2,6, 6-tetramethylpiperidyl) succinate; condensation product between N,N' -bis (2 , 2, 6 , 6- tetramethyl -4 -piperidyl) hexamethylenediamine and 4-morpholine-2, 6-dichloro-l, 3 , 5-triazine; condensation product between 2-chloro-4 , 6-di- (4-n- butylamino-2 ,2,6, 6-tetramethylpiperidyl) -1,3,5- triazine and 1, 2-bis (3-aminopropylamino) ethane; condensation product between 2-chloro-4 , 6-di- (4-n- butylamino-l , 2 , 2 , 6, 6-pentamethylpiperidyl) -1,3,5- triazine and 1, 2-bis (3-aminopropylamino) ethane; 8-acetyl-3-dodecyl-7, 7,9, 9-tetramethyl-l, 3,8- triazaspiro [4.5] decano-2 , 4-dione ; 3-dodecyl-l- (2, 2,6, 6-tetramethyl-4 -piperidyl) pyrrolidin-2 , 5-dione; 3-dodecyl-l- (1, 2,2,6, 6-pentamethyl-4-piperidyl) pyrrolidin-2 , 5-dione. 2.7 Oxamides such as, for example: 4,4'-dioctyloxyoxanilide; 2,2' -diethoxyoxanilide; 2,2' -dioctyloxy-5 , 5 ' -di-t-butoxanilide ; 2,2' -didodecyloxy-5 , 5 ' -di-t-butoxanilide ; 2-ethoxy-2 ' -ethyloxanilide ; N, N' -bis (3-dimethylaminopropyl) oxamide ; 2-ethoxy-5-t-butyl-2 '-ethoxanilide and its mixtures with 2-ethoxy-2 ' -ethyl-5 , 4 ' -di-t-butoxanilide; and mixtures of disubstituted ortho- and para- methoxy anilides and mixtures of disubstituted ortho and para-ethoxy anilides. 2.8 2- (2-hydroxyphenyl) -1,3 ,5-triazines such as, for example: 2,4, 6-tris (2-hydroxy-4-octyloxyphenyl) -1,3,5- triazine; 2-(2-hydroxy-4-octyloxyphenyl) -4, 6-bis (2 , 4-dime- thylphenyl) -1,3 , 5-triazine; 2- (2, 4-dihydroxyphenyl) -4, 6-bis (2 , 4-dimethylphe- nyl) -1, 3, 5-triazine; 2 , 4-bis- (2-hydroxy-4-propyloxyphenyl) -6- (2 , 4- dimethylphen 1) -1, 3 , 5-triazine; 2- (2-hydroxy) -4 , 6-bis ( 4-methylphenyl) -1,3,5- triazine; 2- (2-hydroxy-4-dodecyloxyphenyl) -4, 6-bis (2,4-di- methylphenyl) -1,3, 5-triazine; 2- [ 2-hydroxy-4- ( 2-hydroxy-3-butyloxypropoxy) phenyl] -4 , 6-bis (2 , 4-dimethyl) -1,3, 5-triazine; 2-[2-hydroxy-4-(2-hydroxy-3-octyloxypropyloxy) - phenyl] -4, 6-bis (2, 4-dimethyl) -1, 3 , 5-triazine. 3. "Metal-deactivators" such as, for example: N,N- diphenyloxamide, N-salicylal-N'-salicyloyl-hydra- zine, N,N'-bis(salicyloyl)hydrazine; N,N'-bis(3 ,5- di-t-butyl-4-hydroxyphenylpropionyl)hydrazine, 3- salicyloylamino-1, 2 , 4-triazole, bis (benzylidene) o- xalyl dihydrazide, oxanilide, isophthaloyl dihy- drazide, sebacoyl bisphenylhydrazide, N,N'-diace- tyladipoyl dihydrazide, N,N' -bis (salicyloyl) oxal- lyl dihydrazide, N,N' -bis (salicyloyl) thiopropionyl dihydrazide . 4. Phosphites and phosphonites such as, for example: triphenyl phosphite, diphenyl alkyl phosphites, phenyl dialkyl phosphites, tris (nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris (2, 4 -di-t -butylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, bis (2 , 4-di-t-butyl- phenyl) entaerythritol diphosphite, bis (2 , 5-di-t- butyl-4 -methylphenyl) pentaerythritol diphosphite , diisodecyloxypentaerythritol diphosphite, bis (2,4- di-t-butyl-6-methylphenyl) pentaerythri ol diphos- phite, bis [2, 4, 5-tris (t-butylphenyl) ] pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis- (2, 4-di-t-butyl-phenyl) -4,4 ' -diphenylile- nediphosphonite, 5-iso-octyloxy-2 ,4,8, 10-tetra-t- butyl-12H-di-benzo [d,g] -1, 3 , 2-dioxaphosphocine, 6- fluoro-2 ,4,8, 10 -tetra-t -butyl - 12 -methyl -diben- zo [d,g] -1, 3 , 2-dioxaphosphocine, bis (2 , 4-di-t- butyl-6-methylphenyl) methylphosphite , bis (2 , 4 -di- t-butyl -6-methylphenyl) ethylphosphite . 5. Agents which are capable of destroying peroxides such as, for example, esters of /3-thiodipropionic acid such as lauryl, stearyl, myristyl or tridecyl esters, mercaptobenzimidazole or zinc salt of 2- mercaptobenzimidazole, zinc dibutyldithiocarbama- te, dioctadecyldisulfide pentaerythritol tetrakis (jS-dodecylmercapto)propionate. 6. Stabilizers of polyamides such as, for example, copper salts combined with compounds of iodine and/or phosphorous, divalent manganese salts. 7. Basic co-stabilizers such as, for example: mela- mine, polyvinylpyrrolidone, dicyanodiamide, triallyl cyanurate, derivatives of urea, derivatives of hydrazine, amines, polyamides, polyurethanes, salts of alkaline metals and salts of earth-alkaline metals of fatty acids such as, for example, Ca-stearate, Zn-stearate, Mg-stearate, Mg-behenate, Na-ricinoleate, K-palmitate, antimo- nium-pyrocatecholate , tin-pyrocatecholate . 8. Nucleating agents such as, for example: 4-t-butyl- benzoic acid, adipic acid, diphenylacetic acid. 9. Fillers and reinforcing agents such as, for example: calcium carbonate, silicates, glass fibres, asbestos, talc, kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite. 10. Other additives such as, for example: plastici- zers, lubricants, emulsifying agents, pigments, optical brighteners, flame-re ardants (for example, bromurates, chlorurates, phosphorates and phosphorous/halogen mixtures) , antistatic agents, blowing agents, thiosynergizing agents such as, for example, dilauryl thiodipropionate or diste- aryl thiodipropionate . 11. Benzofuranones and indolinones such as, for ex.: 3- [4- (2 -acetoxyethoxy) phenyl] -5, 7-di-t-butylben- zofuran-2 -one; 5, 7-di-t-butyl-3- [4- (2 -stearoyloxyethoxy) phenyl] benzofuran-2 -one ; 3,3' -bis [5,7-di-t-butyl-3- [4- (2 -hydroxyethoxy) phenyl] benzofuran-2 -one] ; 5, 7-di-t-butyl-3- (4-ethoxyphenyl) benzofuran-2-one; 3- (4-acetoxy-3 , 5-dimethylphenyl) -5, 7-di-t-butyl- benzofuran-2 -one ; 3- (3 , 5-dimethyl-4-pivaloyloxyphenyl) -5 , 7-di-t- butyl-benzofuran-2 -one; or those described in U.S. patents 4.325.863, 4.338.244, 5.175.312, 5.216.052, 5.252.643, 4 316.611, 4.316.622, 4.316.876 or in European patent applications 589.839 and 591.102. Some illustrative but non-limiting examples are provided hereunder for a better understanding of the present invention and for its embodiment . EXAMPLE 1 Preparation of Compound Nr. 1 having the formula: 15 g (0.067 moles) of 2- (2 ' -hydroxy-5 -methyl - phenyl) -2H-benzotriazole, 7.99 g (0.079 moles) of di-n- propylamine, 3.36 g (0.112 moles) of para-formaldehyde and 30 ml of n-butanol are charged into a 3 -necked 100 ml flask, equipped with a drip funnel, thermometer and condenser. The mixture is heated to reflux temperature for 44 hours and the reaction is controlled by thin layer chromatography (T.L.C.) using hexane : ethyl acetate in a ratio 1:1 as mobile phase. At the end of the reaction, the solvent is eliminated by evaporation obtaining the Mannich base corre- sponding to 2- (2 ' -hydroxy-3-dipropylaminomethyl-5- methylphenyl) -2H-benzotriazole . 20 g (0.059 moles) of 2- (2 ' -hydroxy-3 -dipropyl- aminomethyl-5-methylphenyl) -2H-benzotriazole, 7.6 g (0.059 moles) of 5 , 5-dimethyl-2 , 4-imidazolidinedione and 75 ml of 1 , 2 , 4-trimethylbenzene are subsequently charged into a 3 -necked 250 ml flask, equipped with a thermometer and condenser. After heating the mixture until the complete dissolution of the reagents, 0.16 g of sodium methylate are added as catalyst, the tempera- ture is brought to 168 °C in a stream of nitrogen and the mixture is maintained at this temperature for 30 hours . At the end of the reaction, which is controlled by thin layer chromatography (T.L.C.) as described above, the mixture is cooled to room temperature, the catalyst is eliminated by filtration and, after evaporation of the solvent, the desired compound is crystallized in the presence of 2 -methoxyethanol obtaining 18 g of a white powder corresponding to Compound Nr. 1 having the following characteristics: melting point (DSC) : 216°C. I.R. in nujols (cm "1 ): 3100, 1770, 1714 ! H-NMR (200 MHz, CDC1 3 ) δ (ppm) : 1.47 (s, 6H) ; 2.36 (s, 3H) ; 4.84 (s, 2H) ; 5.88 (brs, 1H) ; 7.06 (d, J = 1.6 Hz, 1H) ; 7.45 (dd, 2H) ; 7.89 (dd, 2H) ; 8.13 (d, J = 1.6 Hz, 1H) ; 11.5 (s, 1H) . 13 C-NMR (50 MHz, CDCl 3 ) δ (ppm): 20.6; 25.19; 37.58; 58.84; 117.63; 120.83; 124.97; 127.70; 129.00; 130.45; 142.80; 145.60; 156.20; 176.90. Elemental analysis: 99/23093 ELEMENTAL C 19 H I9 N 5 0 3 ANALYS IS C H N CALCULATED 62.47% 5.21% 19.17% FOUND 62.40% 5.20% 19.14% EXAMPLE 2 Preparation of Compound Nr. 2 having the formula: 15 g (0.046 moles) of 2- (2 ' -hydroxy-5-t-octyl- phenyl) -2H-benzotriazole, 5.45 g (0.054 moles) of di-n- propylamine, 23 g (0.077 moles) of para-formaldehyde and 30 ml of n-butanol are charged into a 3 -necked 100 ml flask, equipped with a drip funnel, thermometer and condenser. The mixture is heated to reflux temperature for 44 hours and the reaction is controlled by thin layer chromatography (T.L.C.) using hexane : ethyl acetate in a ratio 1:1 as mobile phase. At the end of the reaction, the solvent is elimi- nated by evaporation obtaining the Mannich base corresponding to 2- (2 ' -hydroxy-3-dipropylaminomethyl-5-t- octylphenyl) -2H-benzotriazole. 20 g (0.046 moles) of 2- (2 ' -hydroxy-3 -dipropyl- aminomethyl-5-t-octylphenyl) -2H-benzotriazole, 5.9 g (0.046 moles) of 5 , 5-dimethyl-2 , 4-imidazolidinedione and 75 ml of 1, 2 , 4-trimethylbenzene are subsequently charged into a 3 -necked 250 ml flask, equipped with a thermometer and condenser. After heating the mixture until the complete dissolution of the reagents, 0.15 g of sodium methylate are added as catalyst, the temperature is brought to 168°C in a stream of nitrogen and the mixture is maintained at this temperature for 25 hours . At the end of the reaction, which is controlled by thin layer chromatography (T.L.C.) as described above, the mixture is cooled to room temperature, the catalyst is eliminated by filtration and, after evaporation of the solvent, the desired compound is crystallized in the presence of methanol obtaining 19.5 g of a white powder corresponding to Compound Nr. 2 having the following characteristics: melting point (DSC) : 130°C. 'H-NMR (200 MHz, CDC1 3 ) δ (ppm): 0.8 (s, 9H) ; 1.37 (s, 6H) ; 1.48 (s, 6H) ; 1.70 (s, 2H) ; 4.85 (s, 2H) ; 5.91 (brs, 1H) ; 7.05 (d, J = 1.6 Hz, 1H) ; 7.45 (dd, 2H) ; 7.9 (dd, 2H) ; 8.3 (d, J = 1.6 Hz, 1H) ; 11.6 (s, 1H) . I3 C-NMR (50 MHz, CDC1 3 ) δ (ppm) : 25.0; 28.9; 31.0; 32.0; 37.8; 38.2; 56.6; 60.0; 117.6; 118.3; 124.0; 126.0; 127.0; 129.0; 142.2; 142.7; 144.8; 155.0; 177.0. Elemental analysis : ELEMENTAL C 26 H 33 N 5 0 3 ANALYSIS C H N CALCULATED 67.39% 7.13% 15.00% FOUND 67.26% 7.07% 14.90% EXAMPLE 3 Ultraviolet ray absorption data 10 '2 M solutions in chloroform of compounds Nr. 1 and 2 obtained as described above and Tinuvin 900 produced and sold by Ciba Geigy, are prepared. These solutions are analyzed using a diode spectrophotometer of the type "hp 8452A DIODE ARRAY spectrophotometer" and the e molar extinction coefficients at λ = 400 nm are indicated in Table 1. TABLE 1 COMPOUND e (1. cm "1 .mol' 1 ) (400 nm) Nr. 1 40 Nr . 2 46 TINUVIN 900 180 EXAMPLE 4 Thermogravimetric data Using a standard instrument for thermogravimetric analysis (TA Instrument Model 3000 of Mettler) the following isothermal and gravimetric data are determined relating to Compounds Nr. 1 and Nr. 2 which are compared with the data of Tinuvin 900 produced and sold by Ciba Geigy. The data are indicated in Table 2. TABLE 2 COMPOUND ISOTHERM AT 280°C; SCANNING AT Nr. 18 Nl/h N 2 ; TIME IN 10°C/min ; 18 Nl/h MINUTES TO INDICATE N 2 ; TEMPERATURE IN LOSS IN WEIGHT OF °C TO INDICATE LOSS THE STABILIZER IN WT . OF STABILIZER 10% 50% 10% 50% 1 * . 302 387 2 ** 298 362 Tinuvin 900 *** 20 281 319 *: after 20 minutes; **: after 18 minutes; ***: after 4.2 minutes. EXAMPLE 5 Stabilization in polycarbonate 20 g of bisphenol A polycarbonate are dissolved in 100 ml of methylene chloride, at room temperature under stirring. After several hours, when the polycarbonate has completely dissolved, 0.1 g of Compound Nr. 1 or Compound Nr. 2 or Tinuvin 900 are added (addition equal to 0.5%). For comparative purposes a solution without light stabilizers is prepared. Films with a thickness of 100 μm are prepared from the above solutions by casting. The films obtained are subjected to accelerated aging in an Atlas Cl 65 Weatherometer under the following conditions: - black panel temperature: 60°C; relative humidity: 50%. Before beginning the aging and afterwards, at regular intervals, the yellow index (Yl) of the above films is measured using the method ASTM E 313. The crushing time is also analyzed. The results obtained are indicated in Table 3. TABLE 3 COMPOUND EXPOSURE TIME Nr. (h) 250 500 600 800 1000 1500 0.4 4.0 12.4 * - 1 0.3 3.0 5.0 8.0 9.5 10.6 12.6 * 2 0.5 3.6 5.8 8.7 9.3 10.9 12.7 * Tinuvin 900 0.4 3.2 6.0 9.5 10.8 12.0 * * : crushing of sample .

Claims: CLAIMS 2- ( 2 ' -hydroxyphenyl) benzotriazoles having general formula (I) : X represents a hydrogen atom; a halogen atom selected from chlorine and bromine; a linear or branched C -C ιs alkyl group; a linear or branched Cι-Cι 8 alkoxyl group; a cyano group; R represents a halogen atom selected from chlorine and bromine; a linear or branched Ci-Cig alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a C 5 -Cι 8 cycloalkyl group, said cycloalkyl group optionally substituted; a C 7 -C 15 arylalkyl or alkylaryl group; a C 6 -C 14 aryl group, said aryl group optionally substituted; a linear or branched Cι-C 18 alkoxyl group; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted; a group having the formula: a -COR 4 group or a -NR 5 R 6 group wherein R 4 , Rs 5 and R $ , the same or different, represent a linear or branched Cj-Cig alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a c 5 -c i 8 cycloalkyl group, said cycloalkyl group 10 optionally substituted; a C 7 -C 15 arylalkyl or alkylaryl group; a C 6 -C 14 aryl group, said aryl group optionally substituted; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, 15 nitrogen and sulfur, said heterocyclic group optionally substituted; or R represents an ester group having general formula (II) , (III) or (IV) : 20 C 77° (II) \ OR' 0 —CH 2 CH 2 C (III) \ OR' 0 CH 2 CH 2 COC ( IV) \ R ' or an amide group having general formula (V) : 0 II CH 2 CH 2 C— NH — R « (V) wherein R' represents a linear or branched - g alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a C 5 -C 18 cycloalkyl group, said cycloalkyl group optionally substituted; a C 7 -C 15 arylalkyl or alkylaryl group; a C 6 -C 14 aryl group, said aryl group optionally substituted; a linear or branched Cι-C, 8 alkoxyl group; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted; or R represents a 4, 4 ' -ethylidenebisphenol group having formula (VI) : Ri represents a hydrogen atom; a linear or branched C,-C 18 alkyl group; a linear or branched C 2 -C 18 alkenyl group; a linear or branched C 2 -C 18 alkinyl group; a C 5 -C 18 cycloalkyl group, said cycloalkyl group optionally substituted; a C 7 -C I5 arylalkyl or alkylaryl group; a C 6 -C 14 aryl group, said aryl group optionally substituted; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted; an acyl group having general formula (VII) : O / R I c (VII) or an ester group having general formula (VIII) : 0 R* ° -^ (VIII) wherein R ' has the same meanings described above; R 2 and R 3 , the same or different, represent a hydrogen atom; a linear or branched C,-Cι 8 alkyl group; a phenyl group; a heterocyclic group with 5 or 6 atoms containing at least one heteroatom selected from oxygen, nitrogen and sulfur, said heterocyclic group optionally substituted. 2. The 2- (2 '-hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C 5 -C 18 cycloalkyl groups, the C 6 -C 14 aryl groups and the heterocyclic groups with 5 or 6 atoms are substituted with: halogen atoms selected from chlorine and bromine, linear or branched C.,-C 18 alkyl groups, linear or branched C 2 -C alkenyl groups; linear or branched C 2 -C 18 alkinyl groups, OH groups, NH groups, SH groups. 3. The 2- (2 '-hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the 0,-0, 2 alkyl groups are: methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, t-butyl, t-amyl, 2-ethylhexyl, n-σctyl, 1, 1, 3 , 3-tetramethylbutyl, n-dodecyl, 1, 1, 7, 7-tetramethyloctyl, n-octadecyl. 4. The 2-(2 '-hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C 2 -C 18 alkenyl groups are: vinyl, propylene, butylene, pentylene, hexylene. 5. The 2- (2 '-hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C 2 -C^ 8 alkinyl groups are: acetylene, propyne, butyne, 2-butyne. 6. The 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (I) according to claim l, wherein the C 5 -C 18 cycloalkyl groups, optionally substituted, are: cyclohexyl, cyclopentyl, methylcyclohe- xyl. 7. The 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C 7 -C 15 arylalkyl or alkylaryl groups are: benzyl, 2-phenylethyl, 4-t-butylbenzyl . 8. The 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C 6 -C H aryl groups, optionally substituted, are: phenyl, naphthyl, anthracenyl, 2 -hydroxyphenyl . 9. The 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C,-Cι 8 alkoxyl groups are: methoxyl, ethoxyl, propoxyl , n-butoxyl . 10. The 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the heterocyclic groups with 5 or 6 atoms, optionally substituted, are: piperidine, morpholine, piperazine, triazole, tetramethylpiperidine, pentamethylpiperidine, tetramethylmorpholine, pentamethylmorpholine, 4 -hydroxy-tetramethylpi- peridine. 23 11. 2- (2 '-hydroxyphenyl) benzotriazole according to claim 1, having the formula: 2 2- (2 '-hydroxyphenyl) benzotriazole according to claim 1, having the formula: 3 A process for the preparation of the 2- (2 '-hydroxyphenyl) benzotriazoles having general formula (I) according to any of the previous claims, which comprises: (a) reacting a 2- (2 '-hydroxyphenyl) enzotriazole having general formula (IX) : wherein X and R have the same meanings defined above, with a secondary amine having general formula (X) : R 7 N—H (X) R_ wherein R 7 and R 8 , the same or different, preferably the same, represent a linear alkyl group having from 3 or more carbon atoms, in the presence of formaldehyde or para-formaldehyde and an inert organic solvent, at a temperature ranging from 95°C to 100°C, for a time ranging from 40 hours to 60 hours, obtaining the Mannich base having general formula (XI) : ) wherein R, R 7 and R s have the same meanings defined above; (b) ~ reacting the Mannich base having general formula (XI) obtained in step (a) with a 2 , 4-imidazolidinedione having general formula (XII) : 99/23093 wherein R,, R 2 and R 3 have the same meanings described above, in the presence of an alkaline catalyst and an inert organic solvent having a boiling point at 160 °C, at a temperature ranging from 20°C to 200°C, for a time ranging from 20 hours to 30 hours, obtaining a solution from which, after cooling to room temperature and eliminating the catalyst by filtration and the solvent by evaporation, the desired compound is isolated by crystallization in the presence of an inert organic solvent selected from alcohols; monoalkylethers; linear or cyclic aliphatic hydrocarbons; aromatic hydrocarbons; chlorinated aromatic solvents . 14. The process according to claim 13, wherein step (a) is carried out in the presence of para-formaldehyde and n-butanol . 15. The process according to claim 13, wherein the catalysts used in step (b) are: sodium methylate, sodium hydroxide, potassium hydroxide, lithium /23093 hydroxide . 16. The process according to claim 13, wherein the inert organic solvents having a boiling point at 160°C used in step (b) are: 1, 2 , 4-trimethylbenz- ene, 4-isopropylbenzene. 17. The process according to claim 13, wherein step (b) is carried out at a temperature ranging from 40°C to 170°C. 18. The process according to claim 13, wherein the crystallization solvents used in step (b) are: methanol, 2 -methoxyethanol, hexane, heptane, cyclohexane, methylcyclohexane, toluene, chloro- benzene . 19. Polymeric compositions containing an organic poly- mer and an effective quantity of one or more 2- (2 ' -hydroxyphenyl) benzotriazoles with general formula (I) according to any of the previous claims. 20. The polymeric compositions according to claim 19, wherein the 2- (2 'hydroxyphenyl) benzotriazoles having general formula (I) are combined with other stabilizers . 21. The " polymeric compositions according to claim 19 or 20, wherein the organic polymer is selected from polycarbonates . 22. End-products obtained from the processing of the /23093 polymeric compositions according to any of the claims from 19 to 21. 23. Use of the 2- (2 ' -hydroxyphenyl) benzotriazoles having general formula (I) according to any of the claims from 1 to 18, as light stabilizers for organic polymers. 24. Use of the polymeric compositions according to claim 19 or 20, for the production of multilayer systems, wherein the upper layer having a thick- ness of 10-100 μm comprises these compositions, whereas the internal layer does not contain or contains a small quantity of a compound having general formula (I) according to any of the claims from 1 to 18. 25. Use of the polymeric compositions according to claim 19 or 20, as coating or painting compositions .

Inventors: COLOMBO ROSALBA, NERI CARLO, RIVA ROSA MARIA, COLOMBO, ROSALBA, NERI, CARLO, RIVA, ROSA, MARIA
Applicants: COLOMBO ROSALBA, GREAT LAKES CHEMICAL ITALIA, NERI CARLO, RIVA ROSA MARIA, COLOMBO, ROSALBA, GREAT LAKES CHEMICAL ITALIA S.R.L., NERI, CARLO, RIVA, ROSA, MARIA
Application year: 1998
Main classification: C07D403
IPC codes: C07D403, C07D471, C08K5, C08L101