ITMI970719A1 - 2- (2'-HYDROXYPHENYL) BENZOTHRIAZOLS AND PROCEDURE FOR THEIR PREPARATION - Google Patents

Description

DESCRIPTION

The present invention relates to 2

phenyl) benzotriazoles.

More particularly, the present invention relates to 2- (2'-hydroxyphenyl-benzotriazoles containing a 2,4-imidazolidinedione-5,5-dialkyl 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 aforementioned benzotriazoles and the manufactured articles obtained from said compositions.

2- {2'-hydroxyphenylbenzotriazoles useful as light stabilizers are known in the art. However, said benzotriazoles have some drawbacks. In fact, they are often quite volatile, have a low thermal stability and, since they have an absorption at 400 nm, they give a yellow color to the polymers in which they are incorporated.

The Applicant has now surprisingly found that 2- (2'-hydroxyphenylbenzotriazoles containing a 2,4-imidazolidinedione-5,5-dialkyl group in the molecule, are able to overcome the drawbacks of the known art. both a low volatility (they are therefore able to remain inside the stabilized organic polymer for longer) and a high thermal stability. Furthermore, they have a well-defined "cut-off" at λ = 400 nm and a good absorption at the two typical λ of benzotriazoles, around 300 nm and 340 nm and, consequently, do not impart yellow color to the polymers in which they are incorporated.

Therefore, the object of the present invention is 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I):

in which:

X represents a hydrogen atom; a halogen atom selected from chlorine and bromine; a linear or branched C ^ -C ^ alkyl group; a linear or branched C ^ -C ^ alkoxy group; a cyan group;

R represents a halogen atom selected from chlorine and bromine; a linear or branched C1-C18 alkyl group; a linear or branched C2-C1a alkenyl group; a linear or branched C2-C18 alkynyl group; a c5-cia cycloalkyl group, said cycloalkyl group optionally substituted; a C7-C1S arylalkyl or alkylaryl group; a C6 C14 aryl group, said aryl group optionally substituted; a linear or branched CL-C1H alkoxy 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 -COR4 group or a -NR5R8 group in which R4, RS and R6, the same or different from each other, represent a linear or branched C1-C1e alkyl group; a linear or branched C2-C18 alkenyl group; a linear or branched Ca-C1B alkynyl group; a C3-C18 cycloalkyl group / said optionally substituted cycloalkyl group; a C7-C1S arylalkyl or alkylaryl group; a Cfi-C14 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; or R represents an ester group having general formula (II), (III) or (IV):

or an amide group having general formula (V):

wherein R 'represents a linear or branched C1-C1B alkyl group; a linear or branched Ca-Cl1l alkenyl group; a linear or branched Ca-C18 alkynyl group; a C ^ -C ^ cycloalkyl group, said cycloalkyl group optionally substituted; a C7-C15 arylalkyl or alkylaryl group; a C6-C14 aryl group, said aryl group optionally substituted; a linear or branched C1-C1B alkoxy 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'-ethylidene bisphenol group having formula (VI):

R: represents a hydrogen atom; a branched linear C ^ -Cn alkyl group; a linear C2-C18 alkenyl group

or branched; a linear or branched C1B alkynyl group; a C5-C18 cycloalkyl group, said cycloalkyl group optionally substituted; a C7-C1S arylalkyl or alkylaryl group; a C6-C14 aryl group, said optionally substituted aryl 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; an acyl group having general formula (VII):

or an ester group having general formula (VIII):

in which R 'has the same meanings described above;

R2 and R3, the same or different from each other, represent a linear or branched 0χ-018 alkyl group.

Compounds having general formula (I) are useful as light stabilizers for organic polymers.

When the C5-C1B cycloalkyl groups, the C6-C14 aryl groups and the heterocyclic groups with 5 or 6 atoms are defined as optionally substituted, said groups are understood to be substituted with: halogen atoms selected from chlorine and bromine, C ^ - alkyl groups Linear or branched Cig, linear or branched Ca-C1B alkenyl groups, linear or branched Ca-C1a alkynyl groups, OH groups, NH groups, SH groups.

Examples of C ^ -C ^ 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-dodecyl, 1,1,7,7-tetramethyloctyl, n-octadecyl, etc.

Examples of Ca-C1e alkenyl groups are: vinyl, propylene, butylene, pentylene, hexylene, etc.

Examples of Ca-C1B alkynyl groups are: acetylene, propino, butino, 2-butino, etc.

Examples of C5-Clfl cycloalkyl groups, possibly substituted, are: cyclohexyl, cyclopentyl, methylcyclohexyl, etc.

Examples of C7-C15 arylalkyl or alkylaryl groups are: benzyl, 2-phenylethyl, 4-t-butylbenzyl, etc.

Examples of possibly substituted C6-C14 aryl groups are: phenyl, naphthyl, anthracenyl, 2-hydroxyphenyl, etc.

Examples of ε; -01β alkoxy groups are: methoxy, ethoxy, propoxyl, n-butoxy, etc.

Examples of heterocyclic groups with 5 or 6 atoms, possibly substituted, are: piperidine, morpholine, piperazine, triazole, tetramethylpiperidine, pentamethylpiperidine, tetramethylmorpholine, pentamethylmorpholine, 4-hydroxy-tetramethylpiperidine, etc.

Specific examples of compounds having general formula (I), not to be considered in any way limiting the present invention, are:

H.

The compounds having general formula (I) object of the present invention can be prepared by various processes.

A further object of the present invention is 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) consists in reacting a 2- (2'-hydroxyphenyl) benzotriazole having general formula (IX):

in which X and R have the same meanings described above, with a 2,4-imidazolidinedione-5,5-dialkyl-1,3-dimethylol having general formula (X):

in which R2 and R3 have the same meanings described above, in the presence of concentrated sulfuric acid, for example, at a concentration between 80% and 98%, at a temperature between -5'C and 80'C. The desired compound is isolated from the mixture thus obtained by operating according to processes known in the art such as, for example, diluting with water, with a water-ice mixture and removing the solid obtained by filtration followed by washing and crystallization in the presence of inert organic solvents. .

Inert organic solvents useful for carrying out the above crystallization are: alitatic or aromatic hydrocarbons such as, for example, hexane, heptane, toluene, etc; alcohol! such as, for example, methanol, isopropanol, etc; chlorinated aromatic solvents such as, for example, chlorobenzene, etc.

In the case where in the 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I) R represents an ester group having general formula (II) / (III) or (IV), or it represents an amide group having general formula (V ), the reaction between 2- (2'-hydroxyphenyl) benzotriazole having general formula (IX) described above and 2,4-imidazolidinedione-5, 5-dialkyl-1,3-dimethylol having general formula (X) described above , must be carried out in the absence of sulfuryl acid. Said reaction is carried out in the presence of toluene and p-toluenesulfonic acid as catalyst, at a temperature comprised between room temperature and the boiling temperature of the toluene.

The 2- (2'-hydroxyphenyl) benzotriazoles having general formula (IX) can be prepared as described, for example, in the German patent application DE 4,237,817.

The 2,4-imidazolidinedione-5,5-dialkyl-1,3-dimethylol having general formula (X) can be prepared as described, for example, in US patent 4,908,456.

Compounds having general formula (I) can also be prepared by reaction of 2- (2'-hydroxyphenyl) benzotriazole having general formula (IX) described above, with a compound having general formula (XI):

wherein R2 and R3 have the same meanings described above, in the presence of formaldehyde and sulfuric acid operating as described, for example, in US patent 4,077,971.

As already mentioned above, the compounds having general formula (I) object of the present invention can be used as light stabilizers for a wide variety of organic polymers.

Organic polymers capable of being stabilized with the compounds of the present invention are: (1) polymers of monoolefins and diolefins such as, for example, polypropylene, polyisobutylene, polybut-1-ene, poly-4-methylpent-1-ene, polyisoprene or polybutadiene; as well as cycloolefin polymers such as, for example, cyclopentene or norbornene; polyethylene (which may optionally be 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 exemplified in the previous paragraph, preferably polyethylene and polypropylene, can be prepared by various methods known in the literature, preferably by using the following methods:

(a) radical polymerization (generally carried out at 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 the Periodic Table. Said metals generally have one or more ligands such as, for example, oxides, halides, alcoholates, ethers, amines, alkyls, alkenyls and / or aryls which can be π- or σ-coordinated. These metal complexes can be in free form or supported in substrates such as, for example, activated magnesium chloride, titanium (III) chloride, alumina or silicon oxide. Said 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, metal alkyl halides, metal alkyl oxides or metal alkyloxanes, said metals being elements belonging to groups la, 11a and / or Illa of the Periodic Table. The activators can be conveniently modified with other ester, ether, amino or silyl ether groups. Said catalytic systems are usually called Phillips, Standard Oil Indiana, Ziegler (-Natta), TNZ (DuPont), metallocene or "single site catalyst" (SSC).

(2) Mixtures of the polymers described in point (1) such as, for example, mixtures of polypropylene with polyisobutylene; blends of polypropylene with polyethylene (for example, PP / HDPE, PP / LDPE); mixtures of different types of polyethylene (for example, LDPE / HDPE).

(3) Copolymers of monoolefins and diolefins with each other or with other wine monomers such as, for example, ethylene / propylene copolymers, linear low density polyethylene (LLDPE) and its mixtures with low density polyethylene (LDPE), propylene / but -l-ene, propylene / isobutylene copolymers, ethylene / but-1-ene copolymers, ethylene / hexene copolymers, ethylene / methylpentene copolymers, ethylene / heptene copolymers, ethylene / octene copolymers, propylene / butadiene copolymers, isobutylene / butadiene copolymers ethylene / alkyl acrylate, ethylene / alkyl methacrylate copolymers, ethylene / vinyl acetate copolymers and their copolymers with carbon monoxide or ethylene / acrylic acid copolymers and their salts (ionomers) as well as ethylene terpolymers with polypropylene and a diene such as, for example , hexadiene, dicyclopentadiene or ethylidene-norbornene; and mixtures of said copolymers with each other or with the polymers referred to in paragraph (1) such as, for example, polypropylene / ethylene-propylene copolymers, LDPE / ethylene-vinyl acetate copolymers (ÈVA), LDPE / ethylene-acrylic acid copolymers (EAA), LLDPE / ÈVA, LLDPE / EAA, and alternating or "random" polyalkylene / carbon monoxide copolymers and their mixtures with other polymers such as, for example, polyamides.

(4) Hydrocarbon resins (e.g., C5-C8) comprising their hydrogenated modifications (e.g., tackifiers) and blends with polyalkylene and starch.

(5) Polystyrene, poly (p-methylstyrene), poly (amethylstyrene).

(6) Copolymers of styrene or a-methylstyrene with dienes or acrylic derivatives such as, for example, styrene / butadiene, styrene / acrylonitrile, styrene / alkyl methacrylate, styrene / butadiene / alkyl acrylate, styrene / butadiene / alkyl methacrylate, styrene / maleic anhydride, styrene / acrylonitrile / methyl acrylate; mixtures, having a high tensile strength, between styrene copolymers and another polymer such as, for example, a polyacrylate, a polymer of a diene or an ethylene / propylene / diene terpolymer, styrene block polymers such as, for example, styrene / butadiene / styrene, styrene / isoprene / styrene, styrene / ethylene / butylene / styrene or styrene / ethylene / propylene / styrene.

(7) Grafted copolymers of styrene or amethylstyrene such as, for example, styrene in polybutadiene, styrene in polybutadiene or polybutadiene-acrylonitrile copolymers; styrene and acrylonitrile (or methacrylonitrile) in polybutadiene; styrene, acrylonitrile and methyl methacrylate in polybutadiene; styrene and maleic anhydride in polybutadiene; styrene, acrylonitrile and maleic anhydride or maleimide in polybutadiene; styrene and maleimide in polybutadiene; styrene and alkyl acrylates or methacrylates in polybutadiene; styrene and acrylonitrile in ethylene / propylene / diene terpolymers, 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 listed in point (6) such as, for example , blends of copolymers known as ABS, MBS, ASA or AES; (8) Halogen-containing polymers such as, for example, polychloroprene, chlorinated rubber, chlorinated or chlorosulfonated polyethylene, ethylene and chlorinated ethylene copolymers, epichlorohydrin homopolymers and copolymers, in particular polymers of halogen-containing vinyl compounds such as, for example, polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride or polyvinylidene fluoride; and also their copolymers such as, for example, vinyl chloride / vinylidene chloride, vinyl chloride / vinyl acetate or vinylidene chloride / vinyl acetate.

(9) Polymers derived from α, β-unsaturated acids and their derivatives such as, for example, polyacrylates and polymethacrylates, polymethyl methacrylates, polyacrylamides and polyacrylonitriles, modified with butyl acrylate.

(10) Copolymers of the monomers referred to in point (9) with each other or with other unsaturated monomers such as, for example, acrylonitrile / butadiene copolymers, acrylonitrile / alkyl acrylate copolymers, acrylonitrile / alkoxyalkyl acrylate copolymers or acrylonitrile / vinyl halide copolymers alkyl methacrylate / butadiene. (11) Polymers derived from unsaturated alcohols and animins, or their acyl or acetal derivatives such as, for example, polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral, polyallyl phthalate or polyallyl melamine; as well as their copolymers with the olefins referred to in point (1 <)> ·

(12) Homopolymers and copolymers of cyclic ethers such as, for example, polyalkylene glycols, polyethylene oxide, polypropylene oxides or copolymers of the compounds described above with bis-glycidyl ethers.

(13) Polyacetals such as, for example, polyoxymethylene and those polyoxymethylenes which contain ethylene oxide as a comonomer; polyacetals modified with thermoplastic polyurethanes, acrylates or MBS.

(14) Oxides and sulphides of polyphenylene and mixtures of oxides of polyphenylene with styrenic or polyamide polymers.

(15) Polyurethanes derived 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 derived from diamines and dicarboxylic acids and / or from 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 from m-xylene diamine and adipic acid; polyamides prepared from hexamethylenediamine and isophthalic and / or terephthalic acid and with or without an elastomer as a modifier, for example, poly-2,4,4-trimethylhexamethylene terephthalamide or poly-m-phenylene isophthalamide; and also block copolymers of the aforesaid polyamides with polyolefins, olefin copolymers, ionomers or elastomers chemically bonded or grafted; or with polyethers 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 derived from dicarboxylic acids and diols and / or hydroxycarboxylic acids or the corresponding lactones such as, for example, polyethylene terephthalate, 1 polybutylene terephthalate, poly-1,4-dimethylolcyclohexane terephthalate and polyhydroxybenzoates, as well as derived block copolyethers from polyethers with hydroxyl-terminal groups; and also polyesters modified with polycarbonates or MBS. the

(19) Polycarbonates and polyester carbonates.

(20) Polysulfones, polyethersulfones and polyetherketones.

(21) Cross-linked polymers derived from aldehydes on the one hand and from phenols, urea and melaminins on the other, such as, for example, phenol / formaldehyde resins, urea / formaldehyde resins and melamine / formaldehyde resins.

(22) Dried or non-dried alkyd resins. (23) Resins based on unsaturated polyesters derived from copolyesters of saturated and unsaturated dicarboxylic acids with alcohol! polyhydric and vinyl compounds as crosslinking agents, and also the above resins containing halogens and having good flame resistance.

(24) Cross-linkable acrylic resins derived from substituted acrylates such as, for example, epoxy acrylates, urethane acrylates or polyester acrylates.

(25) Alkyd resins, resins based on polyester or acrylate resins cross-linked with melamine resins, urea resins, resins based on polyisocyanates or epoxy resins.

(26) Cross-linked epoxy resins derived from polyepoxides such as, for example, bis-glycidyl ethers or cycloaliphatic diepoxides.

(27) Natural polymers such as, for example, cellulose, rubber, gelatin, and their chemically modified derivatives to give homologous polymers such as, for example, cellulose acetates, propionates and butyrates, or cellulose ethers such as, for example, methyl cellulose ; as well as hydrocarbon resins ("rosins") and their derivatives.

(28) Blends of the above-mentioned polymers ("polyblends") such as, for example, PP / EPDM,

The compounds having formula (I) object of the present invention are particularly useful in the stabilization of polycarbonates.

A further object of the present invention are polymeric compositions containing an organic polymer and an effective amount of one or more compounds having general formula (I).

The compounds having general formula (I) object of the present invention can be used, as such or in combination with other stabilizers, in the above mentioned polymeric compositions.

In general, the aforesaid compounds having general formula (I) are used in quantities ranging from about 0.1% to about 5% by weight on the weight of the polymeric compositions to be stabilized, although the quantity used varies according to the substrate to be stabilized and the application. the final. Preferably, they are added in an amount comprised between about 0/5% and 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 into the organic polymers to be stabilized by means of conventional techniques. Said incorporation can take place before or during the formation of the final manufactured article, for example, by mixing the compounds having general formula (I) in the form of powder with the polymer to be stabilized, or by adding said compounds to the polymer to be stabilized in melt or solution, or by applying a solution or suspension of said compounds to the polymer to be stabilized, possibly evaporating the solvent used. Elastomers can be stabilized as latexes. Another method for incorporating compounds having general formula (I) in organic polymers comprises adding them before or during the polymerization of the corresponding monomers or before crosslinking.

The compounds having general formula (I) or their mixtures, can be added to the polymer to be stabilized also in the form of "masterbatch" which comprises said compounds in a concentration comprised, for example, between 2.5% and 25% by weight.

The compounds having general formula (I) can be conveniently incorporated into the organic polymers to be stabilized by the following methods:

in the form of emulsion or suspension (for example, in the case of latexes or polymers in emulsion);

as a powder blend in the case of conventional addition of additional compounds or blends of organic polymers;

added directly to the apparatus used to process organic polymers (for example, extruders, internal mixers, etc.); s in the form of solution or melted product.

The stabilized polymeric compositions as described above, can be converted into finished products such as, for example, fibers, films, tapes, sheets, multilayer sheets, containers, tubes and other forms, through methods known in the art such as, for example, "casting", hot stamping, spinning, extrusion or injection molding.

Consequently, the present invention also relates to the use of the aforesaid polymeric compositions for the production of manufactured articles.

Of interest is also the use of multi-layer systems, 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 μπι in thickness) to a formed article consisting of a polymer not containing or containing a small amount of a compound having general formula (I). Said application can be carried out during the formation of said article, for example, through a coextrusion. However, the application can also be carried out on the finished shaped article, for example, by lamination with a film or by covering with a solution. The surface layer or layers of the finished article have the function of a UV filter that protects the interior of said 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 multilayer systems, in which the upper layer having a thickness of 10-100 μπι comprises said compositions, while the inner layer does not contain or contains a small amount of a compound having general formula (I) therefore represents a further object of the present invention.

The stabilized polymers as described above have a high resistance to degradation caused by atmospheric agents, in particular a high resistance to UV light. They are therefore able to maintain their color and shine for a long time even when exposed to external agents.

The compositions described above can also be used as compositions for covering or painting ("coating compositions") such as, for example, paints, lacquers, plastic-based compositions.

Preferred for this purpose are the compositions for covering or for painting in which the organic polymer is chosen from:

(a) a thermoplastic polymer selected from thermoplastic polymers containing heteroatoms, in particular nitrogen, sulfur and / or oxygen, in the main chain, styrenic copolymers, grafted styrenic polymers and polymethyl methacrylates (PMMA); or

(b) a paint binder.

Specific examples of thermoplastic polymers (a) containing heteroatoms, in particular nitrogen, sulfur and / or oxygen, in the main chain, are reported below in points 13 to 20. Among these, preferred are polycarbonates, polyesters, polyamides, polyacetals, polyphenylene oxides and polyphenylene sulphides; particularly preferred are polycarbonates, polyesters such as, for example, polyethylene terephthalate (PET), and polyamides (ΡΆ) such as, for example, PA 6 and PA 6/6; even more preferred are polycarbonates.

Specific examples of styrenic copolymers and grafted styrenic polymers (a) are reported below at points 6 and 7.

The binders for paints (b) can comprise at least one of the organic polymers listed below. Specific examples of paints containing specific binders are:

1. paints based on alkyd resins, acrylic resins, polyester resins, epoxy resins or melamine resins, crosslinkable at low or high temperature, or mixtures of said resins, possibly with the addition of a crosslinking agent;

2. two-component polyurethane paints based on acrylic resins containing hydroxyl groups, polyester resins or polyether resins and aliphatic or aromatic isocyanates, isocyanurates or polyisocyanates;

3. one-component polyurethane paints based on block isocyanates, isocyanurates or polyisocyanates which are released during the treatment in the oven;

4. two-component paints based on (poly) -ketoimines and aliphatic or aromatic isocyanates, isocyanurates or polyisocyanates;

5. two-component paints based on (poly) -ketoimines and an unsaturated acrylic resin or a polyacetoacetate resin or a methyl methacrylamidoglycolate;

6. two-component paints based on polyacrylates containing a carboxylic group or an amino group and polyepoxides;

7. two-component paints based on acrylic resins containing an anhydride group and a polyhydroxyl or polyamine compound;

8. two-component paints based on (poly) oxazolines and acrylic resins containing an anhydride group or unsaturated acrylic resins or aliphatic or aromatic isocyanates, or isocyanurates or polyisocyanates;

9. two-component paints based on unsaturated polyacrylates and polymalonates;

10. thermoplastic polyacrylic paints based on thermoplastic acrylic resins or non-crosslinking acrylic resins in combination with etherified melamine resins; L

11. systems for paints based on siloxane-modified acrylic resins;

12. fluoro-modified acrylic resin-based paint systems; And

13. systems for paints based on allyl glycidyl ethers.

The paints can be applied as one or two layers ("one- or two-coat") of coating and the stabilizing compounds having formula (I) are preferably added to the non-colored top coat.

Paints can be applied to the substrate (metal, plastic, wood, etc.) through conventional methods such as, for example, brushing, spray, pouring, dipping or electrophoresis.

A preferred embodiment of the present invention consists of paints or coatings (e.g. automotive coatings) comprising at least one compound having general formula (I). Useful binders for this purpose are, for example, those listed above.

The compounds having general formula (I) object of the present invention can be used, as already mentioned above, in combination with other conventional additives or their mixtures. Said additives are added in quantities ranging from about 0.1% to about 5% by weight of the weight of the polymeric compositions to be stabilized, preferably between about 0.5% and about 3% by weight. By way of example, some of the additives used are listed below.

1. Antioxidants

1.1 Alkylated monophenols such as, for example:

1.2

1.3

for example:

1.4

1.5

example:

1.6

2,2'-methylenebis [6- (α-methylbenzyl) -4-noni1-phenol]; ;

2,2'-methylenebis [6— (α, a— dimethylbenzyl) -4-nonylphenol];

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-methylenyl) -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; ethylene glycol bis [3,3-bis (3'-t-butyl-4'-hydroxyphenyl) butyrate];

bis (3-t-butyl-4-hydroxy-5-methylphenyl) -dicyclopentadiene;

bis [2- (3'-t-butyl-2'-hydroxy-5'-methylbenzyl) -6-t-butyl-4-methylenyl] terephthalate;

1.1-bis (3,5-dimethyl-2-hydroxyphenyl) butane; 2.2-bis (3,5-di-t-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) peritan.

Benzyl compounds containing 0, N or S such as, for example:

3,5,3 ', 5'-tetra-t-butyl— 4,4'— dihydroxybenzyl ether;

octadecyl-4-hydroxy— 3,5— dimethylbenzyl mercaptoacetate;

tris (3,5-di-t-butyl-4-hydroxybenzyl) amine; bis (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) -dithioterephthalate;

bis (3,5-di-t-butyl-4-hydroxybenzyl) sulfide; isooctyl-3,5-di-t-butyl-4-hydroxybenzyl mercaptoacetate.

Hydroxybenzylated maionates such as, for example: dioctadecyl-2,2-bis (3,5-di-t-butyl-2-hydroxybenzyl) maionate;

dioctadecyl-2- (3-t-butyl-4-hydroxy-5-methylbenzyl) malonate;

didodecylmercaptoethyl-2, 2-bis (3,5-di-t-butyl-4-hydroxybenzyl) malonate;

bis [4- (1,1,3,3-tetramethylbutyl) phenyl] -2,2-bis (3,5-di-t-butyl-4-hydroxybenzyl) malonated.

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.

Triazine compounds such as, for example:

2.4-bis (octylmercapto) -6- (3,5-di-t-butyl-4-hydroxyanilino) -1,3,5-triazine;

2-octylmercapto-4,6-bis (3,5-di-t-butyl-4-hydroxyanilino) -1, 3,5-triazine;

2-octylmercapto-4,6-bis (3,5-di-t-butyl— 4-hydroxyphenoxy) -1, 3,5-triazine;

2.4.6-tris- (3,5-di-t-butyl-4-hydroxyphenos-si) -1,2,3-triazine;

1.3.5-tris (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate;

1.3.5-tris (4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate;

2.4.6-tris- (3,5-di-t-butyl-4-hydroxyphenyl-ethyl) -1, 3, 5-triazine;

1.3.5-tris {3,5-di-t-butyl— 4— hydroxyphenylpropionyl) hexahydro-1,3,5-triazine;

1.3.5-tris- {3, 5-dicyclohexyl— 4— hydroxybenzyl) isocyanurate.

Benzylphosphonates such as, for example:

dimethyl-2,5-di-t-butyl— 4— hydroxybenzylphosphonate;

diethyl-3,5-di-t-butyl-4-hydroxybenzylphosphonate;

dioctadecyl-3,5-di-t-butyl-4-hydroxybenzylphosphonate;

dioctadecyl-5-t-butyl-4-hydroxy-3-methylbenzylphosphonate;

calcium salts of the monoethyl ester of 3,5-di-t-butyl-4-hydroxybenzylphosphonic acid.

Acylaminophenols such as, for example:

4-hydroxyl uranilide;

4-hydroxystearanilide;

octyl-N- (3,5-di-t-butyl-4-hydroxyphenyl) carbamate.

Esters of fi- (3,5-di-t-butyl-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-propanodiol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, Ν, Ν'-bis (hydroxyethyl) oxamide, 3-thioundecanol, 3-thiopentethylhexamide trimethylolpropane, 4-hydroxymethyl-1phospho-2,6,7-trioxabicyclo [2 .2.2] octane.

Esters of β- (5-t-butyl-4-hydroxy-3-methylphenyl-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-propanodiol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris {hydroxyethyl) isocyanurate, Ν, Ν'-bis (hydroxyethyl) oxamide, 3-thioundecanol, 3-thiopentethylhexamide trimethylolpropane, 4-hydroxymethyl-1phospho-2,6,7-trioxabicyclo [2 .2.2] octane.

Esters of fi- {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-propanodiol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, Ν, Ν'-bis (hydroxyethyl) oxamide, 3-thioundecanol, 3-thiopentadecanol, trimethylhexane 4-hydroxymethyl-1phospho-2, 6,7-trioxabicyclo [2.2.2] octane.

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, glycol ethylene, 1,2-propanodiol, neopentyl glycol, thiodethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris (hydroxyethyl) isocyanurate, Ν, Ν'-bis (hydroxyethyl) oxamide, 3-thioundecanol, 3-thiopentethylhexane, trimethylhexane , 4-hydroxymethyl-1-phospho-2,6,7-trioxabicyclo [2 .2.2] octane.

Amides of the fi- (3,5-di-t-butyl-4-hydroxyphenyl) -propionic acid such as, for example: Ν, Ν'-bis (3,5-di-t-butyl-4-hydroxyphenyl propionyl ) hexamethylenediamine;

Ν, Ν'-bis (3,5-di-t-butyl-4-hydroxyphenylpro-pionyl) trimethylenediamine;

Ν, Ν'-bis (3,5-di-t-butyl-4-hydroxyphenylpro-pionyl) hydrazine.

2. Ultraviolet and light stabilizers.

2.1 Derivatives of 2- (2'-hydroxyphenyl) benzotriazoles such as, for example:

2- (2 <1> -hydroxy-5'methylphenyl) benzotriazole; 2- (3 ', 5'-di-t-butyl-2'-hydroxyphenyl) benzo-triazole;

2- (5'-t-butyl-2'-hydroxyphenyl-benzotriazoal;

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 <1> -t-butyl-2'-hydroxyphenyl) benzotriazole;

2- (2 <1> -hydroxy-4 <1> -octyloxyphenyl) benzotriazole;

2- (3 ', 5'-di-t-amyl-2'-hydroxyphenyl) -benzo-triazole;

2- [3 ', 5'-bis (α, α-dimethylbenzyl) -2 <1> -hydroxyphenyl Jbenzotriazole;

mixtures of 2- [3'-t-butyl-2'-hydroxy-5 '- (2-octyloxycarbonylethyl) phenyl) -5-chlorobenzo— triazole, 2- [3'-t-butyl-5' - (2- (2-ethylhexiloxy) carbonylethyl) -2'-hydroxyphenyl] -5-chlorobenzotriazole, 2- [3'-t-butyl-2 <1> -hydroxy-5 '- (2-methoxycarbonylethyl) phenyl] -5-chlorobenzotriazole , 2- [3 <1> -t-butyl-2'-hydroxy-5 '- {2-methoxycarbonylethyl) phenyl] benzotriazole, 2- [3' -t-butyl-2 <1> -hydroxy-5'- (2-octyloxycarbonylethyl) phenyl Jbenzotriazole, 2- [3'-t-butyl-5 '- (2- (2-ethylhexyloxy) carbonylethyl) -2'-hydroxyphenyl Jbenzotriazole, 2- (3'-dodecyl-2' -hydroxy-5 <1> -methylphenylJbenzotriazole and 2- [3 '-t-butyl-2'-hydroxy-5' - (2-isooctyloxy— carbonylethyl) phenyl Jbenzotriazole, 2,2'-methylene-bis [4- { 1,1,3,3-tetramethylbutyl) - 6— benzotriazol-2-yl-phenol J;

esterification product of 2- [3'-t-butyl-5 '- (2-methoxycarbonylethyl) -2'-hydroxy-phenyl] -2H-benzotriazole with polyethylene glycol 300;

[R-CH2CHa-COO (CH2) 3] 2 wherein R = 3'-tbutyl-4-hydroxy-5'-2H-benzotriazol-2-yl-phenyl.

2-hydroxybenzophenon derivatives 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.

Esters of benzoic acids, optionally substituted, such as, for example: phenyl salicylate, 4-t-butylphenyl salicylate, octylphenyl salicylate, benzoyl-resorcinol, bis- (4-t-butylbenzoyl) -resorcinol,, dibenzoylresorcinol, 2,4-di -t-butylphenyl-3,5-di-tbutyl-4-hydroxybenzoate, hexadecyl-3,5-di-tbutyl-4-hydroxybenzoate, octadecyl-3,5-dit-butyl-4-hydroxybenzoate, 2-methyl-4 , 6-dit-butylphenyl-3,5-di-t-butyl-4-hydroxybenzoate.

Acrylates such as, for example, ethyl or isoctyl a-cyano-p, p-diphenyl acrylate; methyl a-carbomethoxycinnamate, methyl or butyl a-cyanoβ-methyl-p-methoxycinnamate, methyl a-carbomethoxy-p-methoxycinnamate, N- (β-carbomethoxy- β-cyanovinyl) -2-methylindoline.

Nickel compounds such as, for example, complexes of 2,2'-thio-bis- [4- {1,1,3-tetramethylbutyl) phenol], for example 1: 1 or 1: 2 complexes, with or without additional binders 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, such as methyl or ethyl esters, nickel complexes with kethoxime such as 2-hydroxy-4-methylphenyl undecyl kethoxime, nickel complexes of 1-phenyl-4-lauroyl-5-hydroxypyrazole with or without additional ligands.

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-oxo [4- (2,2,6,6-tetramethyl) piperidinyl] 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 Ν, Ν'-bis (2,2,6,6-tetramethyl-4-piperidyl) hexamethylenediamine and 4-t-octylamino-2,6-dichloro-1,3,5-triazine;

tris (2,2,6,6-tetramethyl-4-piperidyl) nltrilotriacetate;

tetrakis (2,2,6,6-tetramethyl— 4— piperidll) -1,2,3,4-butane-tetracarboxylate;

1,1 <1> - (1,2-ethanodiyl) bis (3,3,5,5-tetramethylplperazinone;

4-benzoyl-2, 2,6,6-tetramethylpiperidine;

4-stearyloxy-2, 2,6,6-tetramethylpiperldine; bis (1,2,2,6,6-pentamethylpiperidyl) -2-n-bu-tyl-2- (2-hydroxy-3,5-di-t-butylbenzyl) mayionate;

3-n-octyl-7,7,9,9-tetramethyl-1,3,8-triaza-spiro [4.5] decan-2,4-dione;

bis (1-octyloxy— 2,2,6,6— tetramethylpiperidyl) sebacate;

bis (1-octyloxy— 2,2,6,6— tetramethylpiperidyl) succinate;

condensation product between N, N'-bis- (2,2,6,6-tetramethyl-4-piperidyl) hexamethylene diamine and 4-morpholine-2,6-dichloro-1,3,5-triazine;

condensation product between 2-chloro4.6-di- {4-n-butylamino-2,2,6,6-tetramethylpiperidyl) -1, 3,5-triazine and 1,2-bis (3-aminopropylanunino )ethane;

condensation product between 2-chloro-4.6-di- (4-n-butylamine-1,2,2,6,6-pentamen-tylpiperidyl) -1, 3,5-triazine and 1,2-bis (3-aminopropylamino) ethane;

8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-1,3,8-triazaspiro [4,5] decane-2,4-dione;

3-dodecyl-1- (2,2,6,6-tetrameters - 4-piperidyl) pyrrolidine-2,5-dione;

3-dodecyl-1- (1,2,2,6,6-pentamethyl-4-piperidyl) pyrrolidine-2,5-dione.

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 <1> -ethyl-5,4'-di-t-butoxanilide; and mixtures of disubstituted ortho- and paramethoxy anilides and mixtures of disubstituted ortho- and para-ethoxy anilides.

2.8 2- (2-hydroxyphenyl) -1 / 3/5-triazirié 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-dimethylphenyl) -1,3,5-triazine;

2- (2,4-dihydroxyphenyl) -4,6-bis (2,4-dimethylphenyl) -1,3,5-triazine;

2,4-bis- {2-hydroxy— 4— propyloxyphenyl) -6— (2,4-dimethylphenyl) -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-dimethylphenyl) -1,3,5-triazine;

2- [2-hydroxy-4- (2-hydroxy-3-butyloxy-pro-possi) phenyl] - 4,6-bis (2,4-dimethyl) -1, 3,5-triazine;

2- [2-hydroxy-4- (2-hydroxy-3-octyloxy-pro-pyloxy) 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-hydrazine, Ν, Ν'-bis (salicyloyl) hydrazine, N, N'-bis- (3, 5-di-t-butyl-4-hydroxyphenylpropionyl) hydrazine, 3-salicyloylamino-1, 2,4-triazole, bis (benzylidene) oxalyl dihydrazide, oxanilide, isophthaloyl dihydrazide, sebacoyl bisphenylhydrazide, Ν, Ν'-diacetyl dihydrazide, , N'-bis (salicyloyl) oxalyl dihydrazide, Ν, Ν'-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) , diisodecyl pentaerythritol diphosphite, bis (2,4-di-t-butylphenyl) pentaerythritol diphosphite, bis (2,5-di-t-butyl-4-methylenyl) pentaerythritol diphosphite, diisodecyloxypentaerythritol diphosphite, bis (2,4-di- t-butyl-6-methylphenyl) pentaerythritol diphosphite, bis [2,4,5-tris- {t-butylphenyl)] pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis- (2,4-dit-butyl-phenyl) -4, 4'-diphenylylenediphosphonite, 5-isooctyloxy-2,4,8,10-tetra-t-butyl-12H-di-benzo [d, g] -1,3,2-dioxaphosphocin, 6-fluoro-2, 4, -8,10-tetra-t-butii-12-methyl-dibenzo [d, g] -1, 3,2-dioxaphosphocin, bis (2,4-di-t-butyl-6-methylphenyl) methylphosphite, bis ( 2,4-di-t-butyl-6-methylphenyl) ethylosphite.

5. Agents that are capable of destroying peroxides such as, for example, β-thiodipropionic acid esters such as lauryl, stearyl, myristyl or tridecyl esters, mercaptobenzimidazole or 2-mercaptobenzimidazole zinc salt, zinc dibutyldithiocarbamate p-dodecylmercapto) -propionate.

6. Polyamide stabilizers such as, for example, copper salts in combination with iodine and / or phosphorus compounds, salts of divalent manganese.

7. Basic co-stabilizers such as, for example:

melamine, polyvinylpyrrolidone, dicyanodiamide, triallyl cyanurate, urea derivatives, hydrazine derivatives, amines, polyamides, polyurethanes, alkali metal salts and alkaline earth metal salts of fatty acids such as, for example, Ca-stearate, Zn- stearate, Mg-stearate, Mg-behenate, Na-ricinoleate, K-palmitate, antimony-pyrocatecolate, tinpyrocatecolate.

8. Nucleating agents such as, for example: 4-tbutyl-benzoic acid, adipic acid, diphenylacetic acid.

9. Fillers and reinforcing agents such as, for example: calcium carbonate, silicates, glass fibers, asbestos, talc, kaolin, mica, barium sulphate, metal oxides and hydroxides, carbon black, graphite.

10. Other additives such as, for example: plasticizers, lubricants, emulsifiers, pigments, optical brighteners, anti-inflammatory agents (for example, brominated, chlorinated, phosphorated and mixed phosphorus / halogens), antistatic agents, expansion agents, thiosynergists such as, for example , dilauryl thiodipropionate or distearyl thiodipropionate.

11. Benzofuranones and Indolinones such as, for example:

3- [4- (2-acetoxyethoxy) phenyl] -5,7-di— t— butylbenzofuran-2-one;

5.7-di-t-butyl— 3— [4- (2-stearohyioxyethoxy) 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-butylbenzofuran-2-one;

3- (3,5-dimethyl-4-pivaloyloxyphenyl) - 5,7— di-tbutyl-benzofuran-2-one;

or those described in U.S. Patent Nos.

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 Nos. 589,839 and 591,102.

In order to better understand the present invention and to put it into practice, some illustrative but not limitative examples of the present invention are given below.

EXAMPLE 1

Preparation of Compound No. 1 having general formula:

11.3 g (0.05 mol) of 2- (2'-hydroxy-5'-methyl) benzotriazole are introduced into a 250 ml 4-neck flask, equipped with a mechanical stirrer, dropping funnel, thermometer and condenser. 67 ml of 98% concentrated sulfuric acid, maintaining the temperature between -5 <*> C and 0 ° C. Subsequently, 9.4 g (0.05 moles) of a 60% aqueous solution of 1.3- dimethylol-5,5-dimethylhydantoin.

The aforesaid mixture is left to soak at 20'C under stirring, then it is kept at this temperature, always under stirring, for 4 hours and, subsequently, it is heated up to 80 ° C for another 2 hours. The crude obtained is poured in 400 ml of ice-water, filtered, then washed to neutral pH.

A solid is thus obtained which is crystallized with 200 ml of methanol. From said crystallization 15 g (yield 82%) of a white powder corresponding to Compound No. 1 are obtained, having the following characteristics:

melting point (DSC): 236 ° C.

1.6 Hz, 1H); 8.3 (brs, 1H); 11.6 {s, 1H).

13C-NMR (200 MHz, CDC13) δ (ppm); 20.3; 22.8; 36.3; 63.7; 117.6; 120.8; 124.8; 127; 127.8; 129.6; 131.7; 142.8; 145; 155.4; 177.3. Mass spectrometry (m / e): [ion M]: 365 (100) *; 279 (91) *; 253 (53) *; 238 (30) *; 91 (9) *; 77 (13) *.

the relative intensity is shown in brackets.

Elementary analysis:

EXAMPLE 2

Preparation of Compound No. 2 having general formula:

16.15 g (0.05 mol) of 2- (2'-hydroxy-5'-t-octyl) are introduced into a 250 ml 4-neck flask, equipped with a mechanical stirrer, dropping funnel, thermometer and condenser. benzotriazole in 67 ml of concentrated sulfuric acid at 98%, maintaining the temperature between -5 "C and 0 ° C. Subsequently they are added, by slow dripping in 30 minutes, always maintaining> the temperature between -5 <*> C and O'C, 9.4 g (0.05 moles) of a 60% aqueous solution of 1,3-dimethylol-5,5-dimethylhydantoin.

The aforementioned mixture is left to soak at 20 ° C under stirring, then it is kept at this temperature, always under stirring, for 3 hours and, subsequently, it is heated up to 80 ° C for another 3 hours. The crude obtained is poured into 400 ml of ice water, filtered, then washed to neutral pH.

A solid is thus obtained which is crystallized with 200 ml of hexane. From said crystallization 19 g (yield 82%) of a white powder corresponding to Compound No. 2 are obtained, having the following characteristics:

melting point (DSC): 138 ° C; ?

I.R. in nujol (cnf <1>): 3100, 1770.1714;

'

Mass spectrometry (m / e): [Ion M '+]: 392 (100) *; 264 (74) *; 463 (53) *; 41 (10) *.

*: intensity il is shown in brackets

relative.

Elementary analysis:

EXAMPLE 3

Thermogravimetry data.

Using a standard thermogravimetric analysis instrument (Mettler TA Instrument Model 3000) are determined '! following isothermal and gravimetric data relating to the Compounds

No. 1 and No. 2 which are compared with the data of Tinuvin 900 marketed by Ciba Geigy. The data are reported in Table 1.

TABLE 1

*: after 23 minutes;

**: after 16 minutes;

***: after 4.2 minutes.

EXAMPLE 4

Stabilization in polycarbonate.

20 g of bisphenol A polycarbonate are dissolved in 100 ml of methylene chloride, at room temperature, under stirring. After a few hours, when the polycarbonate has completely dissolved, 0.1 g of Compound No. 1 or Compound No. 2 or Tinuvin 900 (additive equal to 0.5%) are added. For comparative purposes, a solution free of stabilizers is prepared at

light

From the above solutions, films having a thickness of 100 μπι are prepared by "casting".

The films obtained are subjected to accelerated aging in an Atlas CI 65 Weatherometer under the following conditions:

black panel temperature: 60 ° C;

relative humidity: 50%.

Before starting aging and, thereafter, at regular intervals, the yellow index (YI) is measured using the ASTM E 313 method of the aforementioned films. The crumbling time is also analyzed.

The results obtained are reported in Table 2.

TABLE 2

*: crumbling of the sample.

Claims (1)

CLAIMS 1. 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I): in which: X represents a hydrogen atom; a halogen atom selected from chlorine and bromine; a linear or branched alkyl group; a linear or branched C ^ -Cm alkoxyl group; a cyan group; R represents a halogen atom selected from chlorine and bromine; a linear or branched C1 ~ C1B alkyl group; a linear or branched Ca-C18 alkenyl group; a linear or branched C2-Clf1 alkynyl group; a C5-C1a cycloalkyl group, said cycloalkyl group optionally substituted; a C7-C15 arylalkyl or alkylaryl group; a C6-Cn aryl group, said optionally substituted aryl group; a linear or branched C-i C18 alkoxy 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 -COR4 group or a -NRSR6 group in which R4, RS and Rs, equal or different from each other, represent a linear or branched C ^ -C ^ alkyl group; a linear or branched C2-C1B alkenyl group; a linear or branched C3-Clf1 alkynyl group; a C5-Cl1l cycloalkyl group, said cycloalkyl group optionally substituted; a C7-C15 arylalkyl or alkylaryl group; a C3-C14 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; or R represents ester group having general formula (II), (III) or (IV): or an amide group having general formula (V): wherein R 'represents a C 1-C 1 alkyl group, linear or branched; a linear or branched C2-C1a alkenyl group; a linear or branched C2-C18 alkynyl group; a C5-C18 cycloalkyl group, said cycloalkyl group optionally substituted; a C7-C15 arylalkyl or alkylaryl group; a C3-C14 aryl group, said aryl group optionally substituted; a linear or branched C ^ -C ^ alkoxy 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'-ethylidene bisphenol group having formula (VI): R7 represents a hydrogen atom; a linear or branched C ^ -Cia alkyl group; a linear or branched C1-C1B alkenyl group; a linear or branched C2-C1B alkynyl group; a C5-Cl1l cycloalkyl group, said cycloalkyl group optionally substituted; a C7-C15 arylalkyl or alkylaryl group; a C6-C14 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): or an ester group having general formula (VIII): in which R 'has the same meanings described above; R2 and R3, the same or different from each other, represent a linear or branched alkyl group. 2. 2- (2 <1> -hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C5-C18 cycloalkyl groups, the C6-C14 aryl groups and the 5 or 6 atom heterocyclic groups are substituted with: halogen atoms selected from chlorine and bromine, linear or branched C ^ -CÌB alkyl groups, linear or branched Ca-C1a alkenyl groups, linear or branched C2-C1B alkynyl groups, OH groups, NH groups, SH groups. 3. 2- (2 <1> -hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C1-C1e 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-dodecyl, 1,1,7,7-tetramethyloctyl, n-octadecyl. 4. 2- (2'-hydroxyphenylbenzotriazoles having general formula (I) according to claim 1, wherein the C2-Cla alkenyl groups are: vinyl, propylene, butylene, pentylene, hexylene. 5. 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C2-C18 alkynyl groups are: acetylene, propino, butino, 2-butino. 6. 2- {2 * -hydroxyphenylbenzotriazoles having general formula (I) according to claim 1, wherein the optionally substituted C5-C18 cycloalkyl groups are: cyclohexyl, cyclopentyl, methylcyclohexyl. 7. 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C7-C15 arylalkyl or alkylaryl groups are: benzyl, 2-phenylethyl, 4-t-butylbenzyl. 8. 2- (2'-hydroxyphenylbenzotriazoles having general formula (I) according to claim 1, wherein the C3-C14 aryl groups, optionally substituted, are: phenyl, naphthyl, anthracenyl, 2-hydroxyphenyl. 9. 2- {2'-hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the C ^ -C ^ alkoxy groups are: methoxy, ethoxy, propoxyl, n-butoxy. 10. 2- {2 <1> -hydroxyphenyl) benzotriazoles having general formula (I) according to claim 1, wherein the heterocyclic groups with 5 or 6 atoms, possibly substituted, are: piperidine, morpholine, piperazine, triazole, tetramethylpiperidine, pentamethylpiperidine, tetramethylmorpholine, pentamethylmorpholine, 4-hydroxy-tetramethylpiperidine. 11. 2- (2'-hydroxyphenyl) benzotriazole according to claim 1, having formula: 12. 2- {2'-hydroxyphenyl) benzotriazole according to claim 1, having formula: 13. Process for the preparation of 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I) according to any one of the preceding claims, which consists in reacting a 2- (2'-hydroxyphenyl) benzotriazole having general formula (IX) : in which X and R have the same meanings described above, with a 2,4-imidazolidinedione-5,5-dialkyl-1,3-dimethylol having general formula (X): in which R2 and R3 have the same meanings described above, in the presence of concentrated sulfuric acid, at a concentration between 80% and 98% and at a temperature between -5 ° C and 80'C, obtaining a mixture from which isolate the desired compound by diluting with a water-ice mixture and removing the solid obtained by filtration followed by washing and crystallization in the presence of inert organic solvents. 14. Process according to claim 13, wherein the inert organic solvents useful for carrying out the crystallization are: aliphatic or aromatic hydrocarbons, alcohols, chlorinated aromatic solvents. 15. Process for the preparation of 2— (2'— hydroxyphenyl) benzotriazoles having general formula (I), in the case in which R represents an ester group having general formula (II) # (III) or (IV), or represents a amide group having general formula (V), wherein the reaction between 2- (2'-hydroxyphenyl) benzotriazole having general formula (IX) described above and 2,4-imidazolidinedione-5,5-dialkyl-1,3- dimethylol having general formula (X) described above, is carried out in the presence of toluene and p-toluenesulfonic acid as catalyst, at a temperature comprised between room temperature and the boiling temperature of toluene. 16. Polymeric compositions containing an organic polymer and an effective amount of one or more 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I) according to any one of the preceding claims. 17. Polymeric compositions according to claim 16, wherein the 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I) are used in combination with other stabilizers. 18. Polymeric compositions according to claim 16 or 17, wherein the organic polymer is selected from polycarbonates. 19. Products obtained from the processing of the polymeric compositions according to any one of claims 16 to 18. 20. Use of the 2- (2'-hydroxyphenyl) benzotriazoles having general formula (I) according to any one of claims 1 to 15, as light stabilizers for organic polymers. 21. Use of the polymer compositions according to claim 16 or 17, for the production of multilayer systems, wherein the upper layer having a thickness of 10-100 μπι comprises said compositions, while the inner layer does not contain or contains a small amount of a compound having general formula (I) according to any one of claims 1 to 15. 22. Use of the polymer compositions according to claim 16 or 17, as coating or painting compositions.