WO1993009173A1 - Use of 3-amino-2(benzoylamino)acrylic acid esters as stabilisers for organic materials - Google Patents

Abstract

Use of 3-amino-2(benzoylamino)acrylic acid esters (I) in which R?1 is C1? to C20?-alkyl which may be interrupted by one or more non-adjacent O atoms or NR?5 groups and may bear one or more hydroxyl groups, C2? to C20?-alkenyl, C5? to C8?-alkenyl, C5? to C8?-cycloalkyl or phenyl which may be substituted by one to three C1? to C4?-alkyl groups, C1? to C4?-alkoxy groups, C1? to C4?-alkoxy groups, halogen atoms, hydroxyl groups, phenoxy groups, phenyl radicals, cyano groups or C1? to C4?-alkoxy carbonyl groups; R?2 is hydrogen or C1? to C20?-alkyl; R?3 is a five or six-component unsaturated or saturated heterocyclic ring with up to three hetero atoms from the group nitrogen, oxygen and sulphur, which is additionally benzannulated and may be substituted by one to three C1? to C4?-alkyl groups, C1? to C4?-alkoxy groups, halogen atoms, hydroxyl groups, phenoxy groups, phenyl radicals, cyano groups or C1? to C4?-alkoxycarbonyl groups; R?4 is hydrogen, C1? to C12?-alkyl, C1? to C12?-alkoxy, halogen, hydroxyl, phenoxy, phenyl, cyano or a grouping of the formula -CO-OR?5, -CO-R?5, -O-CO-R?5 of -NH-CO-R?5; R?5 is C1? to C12?-alkyl, C5? to C8?-cycloalkyl or phenyl; and n is 1 to 3, as stabilisers for organic materials.

Description

Use of 3-amino-2- (benzoylamino) acrylic acid esters as stabilizers for organic materials

description

The present invention relates to the use of 3-amino-2- (benzoylamino) acrylic acid esters of the general formula I

CH NR ² R ³

in the

R ¹ C ¹ to C ₂ o al yl, which can be interrupted by one or more non-adjacent O atoms or NR ⁵ groups and can carry one or more hydroxyl groups, C ₂ to C ₂ o alkenyl, C ₅ to C _ß -cycloalkyl or phenyl, which can be substituted by one to three C; - to C -alkyl groups, Cι ~ to C -alkoxy groups, halogen atoms, hydroxyl groups, phenoxy groups, phenyl radicals, cyano groups or Cι ~ to C ₄ alkoxycarbonyl groups, be ¬ draws

R ^{2 is} hydrogen or CT. To C ₂ o ~ alkyl,

R ³ for a five- or six-membered unsaturated or saturated heterocyclic ring with up to three heteroatoms from the group nitrogen, oxygen and sulfur, which additionally benzanelliert and by one to three Cι ~ to C -; - alkyl groups, Cι ~ to C Alkoxy groups, halogen atoms, hydroxyl groups, phenoxy groups, phenyl radicals, cyano groups or C 1 -C 6 -alkoxy-alkoxycarbonyl groups may be substituted, R ^ή are hydrogen, ~ to C ₁₂ alkyl, Ci to Cι ₂ alkoxy, halo gen _r hydroxyl, phenoxy, phenyl, cyano or a Gruppie¬ tion of the formula -CO-OR ^5, -CO-R ^s, Denotes -CO-NHR ⁵ , -O-CO-R ⁵ or -NH-CO-R ⁵ ,

R ^{5 is} Ci to Ci ₂ alkyl, Cs-Cs-cycloalkyl or phenyl and

n represents 1 to 3,

as stabilizers for organic materials.

Since some of the 3-amino-2- (benzoylamino) acrylic esters I are new compounds, the invention further relates to these new compounds. In addition, the invention relates to organic materials containing the compounds I and thus stabilized against the action of light, oxygen and heat, in particular stabilized plastics and paints, and to cosmetic preparations containing the compounds I as light stabilizers.

As is known, organic material, especially plastics and paints, is destroyed very quickly, especially by exposure to light. This destruction usually manifests itself in yellowing, discoloration, cracking or embrittlement of the material. With the previously used light stabilizers and stabilizers, no satisfactory protection against the destruction of organic material by light, oxygen and heat could be achieved.

For example, EP-A 057 160 (1) describes o-hydroxyphenbenztriazole derivatives of the general formula

in which A represents, for example, polyethyleneoxycarbonylalkyl radicals or two o-hydroxyphenylbenztriazole systems connecting polyethylene oxycarbonylalkylene bridge members, sorber recommended for plastics and paints. Although the o-hydroxyphenylbenztriazole derivatives mentioned have the desired spectroscopic properties (strong absorption bands in the range from 280 to 360 nm), they do not meet the requirements set today with regard to their stabilization or light protection effect.

It was therefore an object of the present invention to provide light protection agents or stabilizers which provide effective protection for organic material.

Accordingly, the 3-amino-2- (benzoylamino) acrylic acid esters I defined at the outset were found.

In a preferred embodiment, 3-amino-2- (benzoylamino) acrylic acid esters I are used, in which R ^{1 is} C ¹ -C 4 -alkyl, a grouping of the formula - (CH ₂ -CH ₂ -0) _m H with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _p H with p = 1 to 6, cyclopentyl, cyclohexyl or phenyl denotes.

The radicals R ² and R ^{4 are} preferably hydrogen.

Compounds I are also preferred in which R ^{3 is} a 2-, 3- or 4-pyridinyl radical, a 2-, 4- or 5-pyrimidinyl radical, a 3- or 4-pyridazinyl radical, a 2-pyrazinyl radical or is a 1,3,5-triazinyl radical, these heterocyclic rings can be substituted by one or two C 1 -C ₄ -alkyl groups, C 1 -C ₄ -alkoxy groups, halogen atoms, cyano groups or C 1 -C ₄ -alkoxycarbonyl groups .

The radical R ⁵ preferably denotes C 1 -C ₄ -alkyl, cyclopentyl, cyclohexyl or phenyl.

As straight-chain or branched alkyl radicals, which as Cι ~ to C ₄ -, Cχ ~ to Cio- / CT _. - C 1 to C ₂ and C ₂₀ to C ₂₀ alkyl radicals are mentioned, for example methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl , n-amyl, iso-amyl, sec.-amyl, tert.-amyl, neopentyl, n-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, iso-nonyl, n-decyl , n-undecyl, n-dodecyl, n-tridecyl, iso- Tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-hepta-decyl, n-octadecyl or n-eicosyl.

For example, methoxy methyl, 2-methoxyethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2,3-dimethoxy propyl, 2,3-dihydroxypropyl serves as C: ~ to C ₂ o ~ alkyl interrupted by O or NR ⁵ and carrying hydroxyl groups , 3-0xapentyl, 4-0xaheptyl, 5-hydroxy-3-oxaρentyl, 7-hydroxy-4-oxaheptyl, 1-hydroxy-prop-2-yl, 8-hydroxy-3,6-dioxaoctyl, ll-hydroxy-3 , 6, 9-tri-oxaundecyl, 14-hydroxy-3,6,9,12-tetraoxatetradecyl, 3-aza-pentyl, 3- (N-methylaza) pentyl or 4-azaheptyl.

Examples of straight-chain or branched C ₂ - to C ₂ o-alkenyl radicals are vinyl, allyl, 1-methylvinyl, crotyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl or oleyl to call.

As C ₅ - to Cs-cycloalkyl radicals, especially cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, methylcyclopentyl, dimethylcyclopentyl, methylcyclohexyl, ethylcyclohexyl and dimethylcyclohexyl come into consideration.

As straight-chain or branched alkoxy radicals which are addressed as Cχ ~ to C ₄ - and Cι ~ to Cι ₂ alkoxy radicals are, for example, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, sec. -Butoxy, tert-butoxy, n-pentoxy, iso-pentoxy, sec.-pentoxy, tert-pentoxy, neopentyloxy, n-hexyloxy, n-heptyloxy, n-octyloxy, 2-ethylhexyloxy, n- Nonyloxy, iso-nonyloxy, n-decyloxy, n-undecyloxy or n-dodecyloxy.

Halogen atoms are to be understood as fluorine, iodine, but especially bromine and especially chlorine.

The five- or six-membered unsaturated or saturated heterocyclic rings with up to three helium atoms from the group consisting of nitrogen, oxygen and sulfur, which can also be benzanellated and substituted by the radicals described, are also suitable in addition to the representatives mentioned as preferred Consideration: Tetrahydrofuran, furan, tetrahydrothiophene, thiophene, pyrrolidine, pyrroline, pyrrole, isoxazole, oxazole, thiazole, pyrazole, imidazoline, imidazole, 1,2,3-triazolidine, 1,2,3- and 1,2-triazole, 1,2,3-, 1,2,4- and 1,2,5-0xadiazole, tetrahyropyran, dihydropyran, 2H- and 4H-pyran, piperidine,

1,3- and 1,4-dioxane, morpholine, pyrazine, 1,2,5-oxathiazine, 1,2,3- and 1,2, 4-triazine, benzofuran, thionaphthene, indoline, indole, isoindoline, benzoxazole, Indazole, benzimidazole, chroman, isochroman, 2H and 4H chromium, quinoline, isoquinoline, 1,2,3, 4-tetrahydroisoquinoline, cinnoline, quinazoline, quinoxaline, phthalazine and benzo-1,2, 3-triazine .

If compounds I have substituted phenyl radicals - mono- to trisubstituted phenyl for R ¹ and / or n-fold substituents R ⁴ - the preferred degree of substitution is 2 or in particular 1. Single-substituted phenyl radicals are ortho-, meta - or preferably para-substituted, doubly substituted phenyl radicals often have a 2,4-substitution pattern and triple-substituted phenyl radicals often have a 2,4,6-substitution pattern. If two or three substituents appear, these may be the same or different.

With regard to the spatial position of the substituents on the C-C double bond in the compounds I, the structure I comprises both the respective E and the Z isomers. Mixtures of the two isomers can of course also occur.

Some of the 3-amino-2- (benzoylamino) acrylic acid esters I used according to the invention are already known as defined compounds from the literature reference Heterocycles Vol. 27, No. 4, 1988, pp. 903-909 (2). These are those compounds I in which R ¹ denotes methyl, R ² denotes hydrogen and in one case methyl, R ³ for 2-pyridinyl, 5-methyl-2-pyridinyl, 2-pyrimidinyl, 4-methyl -2-pyrimidinyl,

4-chloro-6-methyl-2-pyrimidinyl, 3-pyridazinyl, 6-chloro-3-pyridazinyl and 2-pyrazinyl and R ^{4 is} hydrogen. However, apart from an indication of certain pharmaceutical suitability, there is no information on the usability of this class of substance in (2). Since compounds I which are not explicitly mentioned in (2) are to be regarded as new, the present invention furthermore relates to 3-amino-2- (benzoylamino) acrylic acid esters of the general formula Ia

in der

in the

R6 Z- - to Cio-alkyl, a grouping of the formula - (CH ₂ -CH ₂ -0) _m H with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _P H denotes p = 1 to 6, cyclopentyl, cyclohexyl or phenyl and

R ^{7 represents} a 3- or 4-pyridinyl radical, a 4- or 5-pyriminyl radical, a 4-pyridazinyl radical or one

1,3,5-triazinyl radical, it being possible for these heterocyclic rings to be substituted by one or two C 1 -C ₄ -alkyl groups, C 1 -C ₄ -alkoxy groups, halogen atoms, cyano groups or C 1 -C ₄ -alkoxycarbonyl groups.

The present invention furthermore relates to 3-amino-2- (benzoylamino) acrylic acid esters of the general formula Ib

in der

in the

R ⁶ Ci to Cio alkyl, a grouping of the formula

- (CH ₂ -CH ₂ -O) _m H with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _P H with p = 1 to 6, cyclopentyl, cyclohexyl or phenyl designated and R ^{8 represents} a 2-pyridinyl radical which is in the 3- or

4-position is substituted by a methyl group or a chlorine atom.

The present invention furthermore relates to 3-amino-2- (benzoylamino) acrylic acid esters of the general formula Ic

in der

in the

R ⁶ Ci to Cio alkyl, a grouping of the formula

- (CH ₂ -CH ₂ -0) _m H with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _p H with p = 1 to 6, cyclopentyl, cyclohexyl or phenyl designated and

R ^{9 represents} a 2-pyrimidinyl radical which is substituted in the 5-position by a chlorine atom or in the 4- and 6-position by a methyl group in each case.

The 3-amino-2- (benzoyl-amino) acrylic acid esters I used in accordance with the invention and in particular also the new compounds Ia to Ic can be advantageously prepared according to (2) by reacting a heterocyclic amine of the general formula HNR ² R ³ with a 3- (dimethylamino) -2- (benzoylamino) acrylic acid ester of the general formula II

N(CH₃)₂ in äquimolarem oder annähernd äquimolare Verhältnis her¬ stellen. Die Verbindungen II sind leicht aus der entspre¬ chend s_.ubstituierten Hippursäure und dem entsprechenden Di- methylformamidacetal erhältlich.

N (CH ₃ ) ₂ produce in an equimolar or approximately equimolar ratio. The compounds II are easy from the corresponding s _. Substituted hippuric acid and the corresponding dimethylformamide acetal available.

The reaction of the heterocyclic amines HNR ² R ³ with the compounds II is advantageously carried out in an organic solvent, preferably an alcohol such as methanol, ethanol, isopropanol, ethylene glycol, ethylene glycol monomethyl, ethyl or butyl ether, diethylene glycol, Diethylene glycol monomethyl, ethyl or butyl ether or triethylene glycol is usually carried out in the presence of 5 to 100 mol% of an acid such as sulfuric acid, phospho acid, p-toluenesulfonic acid or in particular hydrochloric acid at temperatures of 20 to 130 ° C, especially 30 to 100 ° C, and at normal pressure. The reaction is usually complete after 1 to 24 hours.

The 3-amino-2- (benzoylamino) acrylic acid esters I according to the invention are outstandingly suitable for stabilizing organic material against the action of light, oxygen and heat. They are also effective as metal deactivators. They are added to the organic material to be stabilized in a concentration of 0.01 to 5% by weight, preferably 0.02 to 2% by weight, based on the organic material, before, during or after its production puts.

Organic material is understood to mean, for example, cosmetic preparations such as ointments and lotions, pharmaceutical formulations such as pills and suppositories, photographic recording materials, in particular photographic emulsions, or precursors for plastics and lacquers, but in particular plastics and lacquers themselves.

The present invention also relates to organic material, in particular plastics and lacquers, which is stabilized against the action of light, oxygen and heat and which contains the compounds I in the concentrations given above. All known devices and methods for mixing stabilizing agents or other additives into polymers can be used to mix the compounds I according to the invention, especially with plastics.

The organic material stabilized by the compounds I according to the invention may optionally contain further additives, e.g. Antioxidants, light stabilizers, metal deactivators, antistatic agents, flame retardants, pigments and fillers.

Antioxidants and light stabilizers which can be added in addition to the compounds according to the invention are e.g. Compounds based on sterically hindered phenols or costabilizers containing sulfur or phosphorus.

Examples of such phenolic antioxidants are 2,6-di-tert-butyl-4-methylphenol, n-octadecyl-β- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 1, 1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane,

1,3,5-trimethyl-2, 6-tris- (3, 5-di-tert-butyl-4-hydroxybenzyl) -benzene, 1,3, 5-tris- (3, 5-di tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris- [ß- (3,5-di-tert-butyl-4-hydroxyphenyl) propionylethyl] isocyanurate, 1st , 3,5-tris (2,6-dimethyl-3-hydroxy-4-tert-butylbenzyl) isocyanurate and pentaerythritol tetrakis [ß- (3,5-di-tert-butyl -4-hydroxy-phenyl) propionate] mentioned.

Examples of phosphorus-containing antioxidants are tris (nonylphenyl) phosphite, distearylpentaerythritol diphosphite, tris (2, -di-tert-butylphenyl) phosphite, tris (2-tert-butyl-4-methylphenyl) - phosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite and tetra- _(. 2, 4-di-tert-butylphenyl) -4,4'-biphenylene kis- into consideration.

Dilauryl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, pentaerythritol tetris (ß-laurylthiopropionate) and pentaerythritol tetris (ß-hexylthiopropionate) may be mentioned as sulfur-containing antioxidants. Further antioxidants and light stabilizers which can be used together with the compounds I are, for example, 2- (2 ^r -hydroxyphenyl) benzotriazoles, 2-hydroxybenzophenones, aryl esters of hydroxybenzoic acids, α-cyanocinnamic acid derivatives, benzimidazolecarboxylic acid anilides, nickel compounds or oxalic acid anilides.

A particularly good stabilization is obtained if at least one light stabilizer from the class of sterically hindered amines is added to the compounds I in the usual concentration.

Examples of sterically hindered amines are: bis (2,2,6,6-tetramethylpiperidyl) sebacate, bis (1,2,2,6,6-pentamethylpiperidyl) sebacate, the condensation product of 1- Hydroxyethyl-2,2, 6, 6-tetramethyl-4-hydroxypiperidine and succinic acid, the condensation product of N, N ^r -Di- (2,2,6,6-tetramethylpiperidyl) hexamethylene diamine and 4-tert-octylamino -2,6-dichloro-l, 3,5-triazine, tris (2,2,6,6-tetramethylpiperidyl) nitrilotriacetate, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butane-tetra-carboxylate, 1, l ^r - (1,2-ethanediyl) -bis- (3,3,5,5-tetramethylpiperazinone), the condensation products of 4-ami - no-2,2,6,6-tetramethylpiperidines and tetramethylol-acetylene diureas.

Examples of plastics which can be stabilized by the compounds I according to the invention are:

Polymers of mono- and diolefins, e.g. Low-density or high-density polyethylene, polypropylene, linear polybutene-1, polyisoprene, polybutadiene and copolymers of mono- or diolefins or mixtures of the polymers mentioned;

Copolymers of mono- or diolefins with other vinyl monomers, such as, for example, ethylene / alkyl acrylate copolymers, ethylene / alkyl methacrylate copolymers, ethylene / vinyl acetate copolymers or ethylene / acrylic acid copolymers; Polystyrene and copolymers of styrene or α-methylstyrene with dienes and / or acrylic derivatives, such as styrene-butadiene, styrene-acrylonitrile (SAN), styrene-ethyl methacrylate, styrene-butadiene-ethyl acrylate, styrene-acrylonitrile-methacrylate, acrylonitrile Butadiene styrene (ABS) or methyl methacrylate butadiene styrene (MBS);

halogen-containing polymers, e.g. Polyvinyl chloride, polyvinyl fluoride, polyvinylidene fluoride and their copolymers;

Polymers derived from α, β-unsaturated acids and their derivatives, such as polyacrylates, polymethacrylates, polyacrylamides and polyacrylonitriles;

Polymers derived from unsaturated alcohols and amines or from their acyl derivatives or acetals, e.g. Polyvinyl alcohol and polyvinyl acetate;

Polyurethanes, polyamides, polyureas, polyesters, polycarbonates, polysulfonates, polyether sulfones and polyether ketones.

Coatings can also be stabilized with the compounds I according to the invention, e.g. Industrial paints. Among these, stove enamels, among them in turn vehicle paints, preferably two-coat paints, are particularly noteworthy.

The compounds I can be added to the lacquer in solid or dissolved form. Their good solubility in coating systems is of particular advantage.

The additional additives already listed, in particular antioxidants and light stabilizers, can also be used when used as stabilizers in paints.

The compounds I according to the invention are particularly suitable for stabilizing polystyrene, copolymers of styrene-acrylonitrile (SAN) and acrylonitrile-butadiene-styrene (ABS), polyurethanes, polyamides, polyesters, polyolefins, in particular ethylene and propylene polymers, and of Paints. A particularly good stabilization of polyurethanes is obtained if the polyurethane is stabilized with a mixture of at least one of the above-mentioned antioxidants and at least one of the above-mentioned sterically hindered amine compounds.

Furthermore, the 3-amino-2- (benzoylamino) acrylic esters I according to the invention are also suitable as light protection agents in cosmetic preparations, that is to say in particular for the precautionary protection of human skin from the damaging effect of light, especially sunlight, but also artificial ¬ chem light, which has high UV components. Organic materials are therefore also to be understood in the broadest sense of the human skin. The cosmetic preparations as such are of course also stabilized in order to remain effective for as long as possible.

Accordingly, the present invention also relates to cosmetic preparations which contain 0.1 to 10% by weight, preferably 1 to 7% by weight, based on the amount of the cosmetic preparation, of one or more 3-amino-2 - (Benzoyla¬ mino) acrylic acid ester I as a light stabilizer. Such cosmetic preparations are, for example, sun protection preparations in liquid, solid or pasty form, such as creams, lotions, aerosol foam creams, gels, oils, fatty pencils, powders or sprays.

The compounds I are used in the cosmetic preparations in the customary carrier media or diluents, for example as a solution in a cosmetic oil. Typical oil components in cosmetics are, for example, paraffin oil, glyceryl stearate, isopropyl myristate, diisopropyl adipate, 2-ethylhexanoic acid cetyl stearyl ester, hydrogenated polyisobutene, petrolatum, caprylic acid / capric acid triglycerides, microcrystalline wax, lanolin and stearic acid. The good solubility of the compounds I in these oil components is particularly advantageous.

The compounds I according to the invention are notable for good compatibility with the customary types of plastics and for good solubility in the customary coating systems and in the customary cosmetic oils. As a rule they have no or only a very slight intrinsic color The usual plastic and paint processing temperatures are stable and non-volatile, show only a low tendency to migrate and, above all, bring about a long protection period for the organic materials treated with them.

Manufacturing examples

example 1

14.9 g (0.06 mol) of 2-benzoylamino-3-dimethylamino-acrylic acid methyl ester and 5.7 g (0.06 mol) of 2-aminopyrimidine were concentrated in 30 ml of ethanol with the addition of 3 ml. Hydrochloric acid heated under reflux for 2 h. The mixture was then cooled to room temperature, the precipitate was filtered off and recrystallized from ethanol. 13 g (corresponding to a yield of 74%) of methyl 2-benzoylamino-3- (2-pyrimidinylamino) acrylate were obtained in the form of colorless crystals of melting point 184 ° C.

The spectroscopic data are given in Table 1.

Examples 2 to 11

Analogously to Example 1, the products listed in Table 1 were prepared from 2-benzoylamino-3-dimethylamino-acrylic acid methyl ester using the corresponding heterocyclic amines. The melting points and the spectroscopic data of the products are also given in Table 1.

Table 1

Structure, melting point and spectroscopic data of the 3-amino-2- (benzoylamino) acrylic acid esters I prepared

Anwendungsbeispiele

Examples of use

A mixture of was used to produce exposure samples from polyurethane

100 g of a polyol component of the composition

41.9 g of a polyetherol of OH number 29 with about 84% primary hydroxyl groups, obtained by addition of propylene oxide and ethylene oxide to polypropylene glycol,

42.5 g of a polyetherol of OH number 27 with about 88% primary hydroxyl groups, obtained by addition of propylene oxide and ethylene oxide to trimethylolpropane, and 8.1 g of 1,4-butanediol,

1.7 g of a 25% by weight solution of 1,4-diazabicyclo [2.2.2] octane in 1,4-butanediol,

0.02 g of a commercially available silicone stabilizer,

5.5 g of fluorotrichloromethane and

0.2 g water

with 0.5 g of the product from Example 1 or 2 or for comparison with the same amount of an agent of the prior art,

0.5 g of bis (1, 2,2, 6, 6-pentamethylpiperidyl) sebacate and 0.25 g of an antioxidant mixture of 9% by weight α-tocopherol and 91% by weight tris (nonylphenyl) phosphite and 48.5 g of a prepolymer containing 23% by weight of isocyanate groups, prepared from

87.2% by weight of 4,4'-diphenylmethane diisocyanate,

4.8% by weight of a polyetherol of OH number 250, obtained by adding propylene oxide to propylene glycol, and 8.0% by weight of dipropylene glycol

at 25 ° C component and tool temperature to test plate. foamed. The test plates were exposed in Hanau's Xenotest® 450 and the yellowness index (YI) was determined on the samples in accordance with the Annual Book of ASTM Standards D 1925-70 (Reapproved 1977) as a measure of the degree of yellowing. The results are summarized in Table 2.

Table 2

Yl values of polyurethane samples

(*) Reaction product of a benzotriazole derivative of the formula

CH₂) ₂COOCH₃

CH ₂ ) ₂ COOCH ₃

with a polyethylene glycol with an average molecular weight of 300 according to literature reference (1)

Claims

Claims 1. Use of 3-amino-2- (benzoylamino) acrylic acid esters of the general formula I

in the R ¹ C: ~ to C ₂ o ~ alkyl, which can be interrupted by one or more non-adjacent O atoms or NR ⁵ groups and can carry one or more hydroxyl groups, C ₂ - to C ₂ o-alkenyl, C ₅ - to Cs-Cyclo- ^' alkyl or phenyl, which by one to three C - to C ^ -alkyl groups, Cι ~ to C -alkoxy groups, halogen atoms, hydroxyl groups, phenoxy groups, phenyl radicals, cyano groups or Cι ~ to C ₄ -alkoxycarbonyl groups may be substituted, R ^{2 is} hydrogen or C: ~ to C ₂ o ~ alkyl, R ³ for a five- or six-membered unsaturated or saturated heterocyclic ring with up to three heteroatoms from the group consisting of nitrogen, oxygen and sulfur, which additionally fuses with benzene and is substituted by one to three C: ~ to C ₄ -alkyl groups, C 1 -C 4 -alkoxy groups, halogen atoms, hydroxyl groups, phenoxy groups, phenyl radicals, cyano groups or C 1 -C 4 -alkoxycarbonyl groups may be substituted, R ^{4 is} hydrogen, C -_- to -CC ₂ alkyl, C _: - to C ₂ -alkoxy, halogen, hydroxyl, phenoxy, phenyl, cyano or a grouping of the formula -C0-0R ⁵ , -CO-R ⁵ , - CO-NHR ⁵ , Denotes -O-CO-R ⁵ or -NH-CO-R ⁵ , R ^{5 is} C 1 -C 1 -alkyl, Cs-C ₈ -cycloalkyl or phenyl, and n represents 1 to 3, as stabilizers for organic materials. 2. Use of 3-amino-2- (benzoylamino) acrylate I according to claim 1, in which R ^{1 is} C: ~ to C: o ~ alkyl, a grouping of the formula - (CH ₂ -CH ₂ -O ) _r rH with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _P H with p = 1 to 6, cyclopentyl, cyclohexyl or phenyl. 3. Use of 3-amino-2- (benzoylamino) acrylates I according to claim 1 or 2, in which R ^{2 is} hydrogen. 4. Use of 3-amino-2- (benzoylamino) acrylic acid esters I according to claims 1 to 3, in which R ^{3 is} a 2-, 3- or 4-pyridinyl radical, a 2-, 4- or 5-pyrimidinyl radical , a 3- or 4-pyridazinyl radical, a 2-pyrazinyl radical or a 1,3,5-triazinyl radical, these heterocyclic rings being substituted by one or two C 1 -C ₄ -alkyl groups, C 1 -C ₄ -alkoxy groups, Halogen atoms, cyano groups or C - to C ₄ -alkoxycarbonyl groups can be substituted. 5. Use of 3-amino-2- (benzoylamino) acrylic esters I according to claims 1 to 4, in which R ⁴ denotes hydrogen. 6. 3-amino-2- (benzoylamino) acrylic acid ester of the general formula Ia

in the R ⁶ C -_- to C; c-alkyl, a grouping of the formula - (CH ₂ -CH _? -0) r _r .H with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _p H with p = 1 to 6, cyclopentyl, cyclohexyl or phenyl and R ^{1 represents} a 3- or 4-pyridinyl radical, a 4- or 5-pyrimidinyl radical, a 4-pyridazinyl radical or a 1, 3, 5-triazinyl radical, these heterocyclic rings being substituted by one or two C 1 -C ₄ -alkyl groups, C 1 -C ₄ -alkoxy groups Halogen atoms Cyano groups or C: ~ to C -alkoxycarbonyl groups can be substituted. 7. 3-Amino-2- (benzoylamino) acrylic acid ester of the general formula Ib

in the R ⁶ C; - to Cic-alkyl, a grouping of the formula - (CH ₂ -CH ₂ -O) ^ H with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _p H with p = 1 to 6, cyclopentyl, cyclohexyl or phenyl designated and R ^{8 represents} a 2-pyridinyl radical which is substituted in the 3- or 4-position by a methyl group or a chlorine atom. 8. 3-Amino-2- (benzoylamino) acrylic acid ester of the general formula Ic

in the R ⁶ C; - to C c ~ alkyl, a grouping of the formula - (CH ₂ -CH ₂ -O) _m H with m = 1 to 10, a grouping of the formula - [CH (CH ₃ ) -CH ₂ -0] _p H with p = 1 to 6, cyclopentyl, cyclohexyl or phenyl and R ^{9 represents} a 2-pyrimidinyl radical which is substituted in the 5-position by a chlorine atom or in the 4- and 6-position by a methyl group in each case. 9. Organic materials stabilized against the action of light, oxygen and heat, containing 0.01 to 5% by weight, based on the amount of the organic material, of one or more 3-amino-2- (benzoylamino) acrylic acid ester I according to claims 1 to 5. 10. Plastics and lacquers stabilized against the action of light, oxygen and heat, containing 0.01 to 5% by weight, based on the amount of the plastics or lacquer, of one or more 3-amino-2- (benzoylami¬ no ) acrylic acid ester I according to claims 1 to 5. 11. Cosmetic preparations containing 0.1 to 10% by weight, based on the amount of the cosmetic preparations, of one or more 3-amino-2- (benzoylamino) acrylate I as claimed in claims 1 to 5 as light protection agent . 12. A method for stabilizing organic materials, characterized in that 3-amino-2- (ben¬ zoylamino) acrylic acid ester I according to claims 1 to 5 is used for this. 13. A method for stabilizing plastics and paints, characterized in that 3-amino-2- (ben¬ zoylamino) acrylic acid ester I according to claims 1 to 5 is used for this. 14. A method for protecting human skin from exposure to light, characterized in that cosmetic preparations are used here which contain 3-amino contain no-2- (benzoylamino) acrylic acid esters I according to claims 1 to 5 as light stabilizers.