Description The present invention relates to a polyethylene pipe comprising components A) and B), wherein component A) is a hindered amine light stabilizer containing a triazine residue, component B) is a natural or synthetic hydrotalcite and the weight ratio of component A) to component B) is 1 : 10 to 10: 1 , preferably 1 :5 to 5: 1. In more detail, the pipe according to the present invention preferably consists of a polyethylene composition comprising the components A) and B) in a weight ratio of 1 :10 to

10:1 .

Component A) is in particular at least one compound of the formula (A-l), (A-ll) or (A-lll)

wherein An is C2-Ci8alkylene, Cs-Crcycloalkylene or

Ci-C4alkylenedi(C5-C7cycloalkylene),

the radicals A12 independently of one another are hydrogen, Ci-Ci2alkyl or

C5-Ci2cycloalkyl, Ai3 and A14 independently of one another are hydrogen, Ci-Ci2alkyl, C5-Ci2cycloalkyl or a group of the formula (a-1 ), or the radicals A13 and A14, together with the nitrogen atom to which they are bonded, form a 5- to 10-membered heterocyclic ring and

ai is a number from 1 to 20, preferably 2 to 20, and the repeating units are identical or different;

wherein A21 and A25 independently of one another are hydrogen, Ci-Ci2alkyl, C5- Ci2cycloalkyl or a group of the formula (a-1 ),

A22, A23 and A24 independently of one another are C2-Cioalkylene, and

Xi , X2, X3, X4, X5, Χβ, X7 and Xs independently of one another are a group of the formula (a-2),

in which A26 is hydrogen, Ci-Ci2alkyl, C5-Ci2cycloalkyl or a group of the formula (a-1 ) as defined above, and A27 has one of the meanings of A12;

wherein

Ri and R2 independently of one another are hydrogen, Ci-C22alkyl, -0-, -OH, -CH2CN, Ci-Cisalkoxy, C2-Cisalkoxy substituted by -OH; C5-Ci2cycloalkoxy, C3-C6alkenyl, C3-C6alkenyloxy, Cz-Cgphenylalkyl unsubstituted or substituted on the phenyl by 1 , 2 or 3 Ci-C ₄ alkyl; or d-Csacyl; and

R3 and R ₄ independently of one another are Ci-C22alkyl or a group of the formula (a-3)

wherein Ro has one of the meanings of Ri and R2.

Component B) is preferably a mixed hydroxide of the formula (B-l) or (B-l l).

M ²⁺ _l-a M ³⁺ a(OH)2(A ^b -)a/ _b x c H ₂ 0 (B-l) M ²⁺ _d AI ³⁺ ₂ (OH)2d ₊ 6-eb(A ^b -)e x f H ₂ 0 (B-l l)

M ²⁺ is for example Ca ²⁺ , Mg ²⁺ , Sr ²⁺ , Ba ²⁺ , Zn ²⁺ , Pb ²⁺ , Sn ²⁺ or Ni ²⁺ .

M ³⁺ is for example Al ³⁺ , B ³⁺ or Bi ³⁺ . a is for example a number up to 0.5.

A ^b - is an anion of valency b, for example Ch, Br, NO ^3" , CO3 ^2" , SO4 ^2" or Se0 ₄ ^2" .

b is for example an integer from 1 to 4.

c is for example zero or a number up to 2.

d is for example a number up to 6.

e is for example a number up to 2.

f is for example zero or a number up to 15.

Hydrotalcites which are of interest are layered double hydroxides that contain positively charged hydroxide layers and charge balancing anions located in the interlayer region.

Component B) is in particular at least one magnesium aluminum hydroxide carbonate hydrate which is for example commercially available as Hycite ^® 713, ^® DHT-4A, ^® DHT- 4V, ^® DHT-4A-2, ^® DHT-4C or Sorbacid ^® 91 1 , or zinc aluminum hydroxide carbonate hy- drate which is for example commercially available as ^® ZHT-4V or Sorbacid ^® 944, or mixtures thereof.

Of particular interest is a magnesium aluminum hydroxide carbonate hydrate which is for example commercially available as Hycite ^® 713 or DHT-4A.

Examples of alkyl having up to 22 carbon atoms are methyl, ethyl, propyl, isopropyl, n- butyl, sec-butyl, isobutyl, tert-butyl, 2-ethylbutyl, n-pentyl, isopentyl, 1 -methylpentyl, 1 ,3-dimethylbutyl, n-hexyl, 1 -methylhexyl, n-heptyl, isoheptyl, 1 ,1 ,3,3-tetramethylbutyl, 1 -methylheptyl, 3-methylheptyl, n-octyl, 2-ethylhexyl, 1 ,1 ,3-trimethylhexyl, 1 ,1 ,3,3-tetra- methylpentyl, nonyl, decyl, undecyl, 1-methylundecyl, dodecyl, 1 ,1 , 3,3,5, 5-hexamethyl- hexyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl and eicosyl. Ci-Cisalkoxy is for example methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, pentoxy, isopentoxy, hexoxy, heptoxy, octoxy, decyloxy, dodecyloxy, tetradecyloxy, hexadecyloxy or octadecyloxy.

C2-Ci8alkoxy substituted by -OH is for example 2-hydroxyethoxy.

C5-Ci2cycloalkyl is for example cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cy- clodecyl or cyclododecyl. Cs-CsCycloalkyl, in particular cyclohexyl, is preferred.

C5-Ci2cycloalkoxy is for example cyclopentoxy, cyclohexoxy, cycloheptoxy, cyclooc- toxy, cyclodecyloxy or cyclododecyloxy. Cs-CsCycloalkoxy, in particular cyclopentoxy and cyclohexoxy, is preferred.

C3-C6alkenyl is for example allyl, 2-methallyl, butenyl, pentenyl or hexenyl. Allyl is preferred. The carbon atom in position 1 is preferably saturated.

C3-C6alkenyloxy is for example propenyloxy.

C7-Cgphenylalkyl unsubstituted or substituted on the phenyl by 1 , 2 or 3 Ci-C4alkyl is for example benzyl, 2-phenylethyl, methylbenzyl, dimethylbenzyl, trimethylbenzyl or tert-butyl benzyl.

Examples of d-Csacyl are formyl, acetyl, propionyl, butyryl, pentanoyl, hexanoyl, hep- tanoyl, octanoyi, acryloyi, methacryloyi and benzoyl. d-CsAlkanoyl, Cs-Csalkenoyl and benzoyl are preferred. Acetyl and acryloyi are especially preferred.

Examples of alkylene having up to 18 carbon atoms are ethylene, propylene, tri- methylene, tetramethylene, pentamethylene, 2,2-dimethyltrimethylene, hexamethylene, trimethylhexamethylene and octamethylene. C2-C6alkylene, in particular hexamethylene is preferred. An example of Cs-Czcycloalkylene is cyclohexylene.

An example of Ci-C4alkylenedi(C5-C7cycloalkylene) is methylenedicyclohexylene. A preferred example of a 5-to 7-membered heterocyclic ring is a morpholine group. The meanings of the terminal groups which saturate the free valences in the compounds of the formula (A-l) depend on the processes used for their preparation. The terminal groups can also be modified after the preparation of the compounds.

If the compounds of the formula (A-l) are prepared by reacting a compound of the formula

in which Xo is, for example, halogen, in particular chlorine, and A13 and A14 are as defined above, with a compound of the formula

in which An and A12 are as defined above, the terminal group bonded to the diamino radical is for example hydrogen or and the terminal group bonded to the triazine radical is for example Xo or

If Xo is halogen, it is advantageous to replace this, for example, by -OH or an amino group when the reaction is complete. Examples of amino groups which may be mentioned are pyrrolidin-1 -yl, morpholino, -IMH2, -N(Ci-C8)alkyl)2 and -NRo(Ci-C8alkyl), in which Ro is hydrogen or a group of the formula (la).

One of the preferred compounds of the formula (I) is

wherein Ei is and ai is a number from 1 to 10, preferably 2 to 10. The preparation of this compound is described in Example 10 of US-A-6,046,304.

According to a preferred embodiment

An is C2-Cioalkylene,

the radicals A12 independently of one another are hydrogen, Ci-C4alkyl or cyclohexyl, Ai3 and A14 independently of one another are hydrogen, Ci-C4alkyl, cyclohexyl or a group of the formula (a-1 ), or the radicals A13 and A14, together with the nitrogen atom to which they are bonded, form a morpholino group and

ai is a number from 1 to 10, preferably 2 to 10, and the repeating units are identical or different;

A21 and A25 independently of one another are hydrogen, Ci-C4alkyl or cyclohexyl, A22, A23 and A24 independently of one another are C2-Cioalkylene, and

Xi , X2, X3, X ₄ , X5, Χβ, X7 and Xs independently of one another are a group of the formula (a-2),

H ₃ C C H ₃

N— A27 (a-2)

^A26 H ₃ C C H ₃ in which A26 is hydrogen, Ci-C4alkyl, cyclohexyl or a group of the formula (a-1 ) as defined above, and A27 has one of the meanings of A12;

Ri and R2 independently of one another are hydrogen, Ci-C4alkyl or cyclohexyl; and R3 and R4 independently of one another are Ci-C4alkyl or a group of the formula (a-3)

wherein Ro has one of the meanings of Ri and R2.

According to a further preferred embodiment component A) is a compound of the formula (A-l-1 ), (A-l-2), (A-ll-1 ) or (A-lll-1 ),

with ai being 2 to 10,

with ai being 2 to 10,

w

The polyethylene pipe may additionally comprise a component C) which is a phenolic antioxidant, in particular 1 ,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6- trimethylbenzene (lrganox ^® 1330), ethylene bis[3,3-bis(3-tert-butyl-4- hydroxyphenyl)butyrate] (Hostanox ^® 03) or 1 ,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)- isocyanurate (lrganox ^® 31 14). The weight ratio of component A) to component C) is preferably 1 :10 to 10:1 , in particular 1 :5 to 5:1.

The polyethylene pipe may further comprise a component D) which is at least one compound selected from the group consisting of phosphites, phosphonites, hydroxyla- mines, tocopherols and tocopherol acetates. A phosphite, for example tris(2,4-di-tert- butylphenyl) phosphite, [3,3',5,5'-tetra-tert. butyl-1 ,1 'biphenyl-2,2'-diyl]-[ 3-(3-methyl-4- hydroxy-5-tert.butyl-phenyl)-propyl]-phosphite, [2,2'-ethylene-bis-(4,6-di-tert. butyl- phenyl)-1 ,1 '-diyl]-[1 ,6-dimethyl-4-(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]- phosphite, [2,2'-ethylene-bis-(4,6-di-tert. butyl-phenyl)-1 ,1 '-diyl]-[1 -methyl-6-tert. butyl- 4-(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]-phosphite or 6-[3-(3-tert-butyl-4- hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra-tert- butyldibenzo[d,f][1 ,3,2]dioxaphosphepin, is particularly preferred. The weight ratio of component A) to component D) is preferably 1 :10 to 10:1 , in particular 1 :5 to 5:1.

Of interest is a polyethylene pipe which comprises components A), B), C) and D). The compounds of components A), B), C) and D) are known and are in essential commer- cially available.

Component A) is preferably present in the polyethylene in an amount of 0.01 % to 2% by weight relative to the weight of the polyethylene. Component B) is preferably present in the polyethylene in an amount of 0.01 % to 5% by weight relative to the weight of the polyethylene.

Component C) is preferably present in the polyethylene in an amount of 0.1 % to 5% by weight relative to the weight of the polyethylene.

Component D) is preferably present in the polyethylene in an amount of 0.1 % to 5% by weight relative to the weight of the polyethylene. According to a preferred embodiment the polyethylene pipe may additionally comprise a pigment, preferably a blue pigment.

The polyethylene of the pipe is preferably selected from HD-PE, MD-PE, LD-PE, LLD- PE, metallocene PE, PE-X, mixture of PE, recycled PE, bi-modal PE, PE-RT, PE 32, PE 40, PE 63, PE 80, PE 100, PE 1 12, PE 125, PE 100 RC, PE 100 RT and PE 100 RD, in particular from high density polyethylene (HD-PE), medium density polyethylene (MD-PE), low density polyethylene (LD-PE), linear low density polyethylene (LLD- PE), metallocene polyethylene, crosslinked polyethylene (PE-X), recycled polyethylene, bi-modal polyethylene and mixtures of polyethylenes.

A particularly preferred polyethylene pipe comprises the components (A), (B), (C) and (D), wherein component (A) is

with ai being 2 to 10,

component (B) is a natural or synthetic hydrotalcite,

component (C) is 1 ,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethyl benzene, and

component (D) is tris[2,4-di-tert-butylphenyl]phosphite.

The polyethylene of the pipe according to the present invention may further comprise one or more conventional additives such as:

1 . Antioxidants

1 .1 . Alkylated monophenols, for example 2,6-di-tert-butyl-4-methylphenol, 2-tert-butyl- 4,6-dimethylphenol, 2,6-di-tert-butyl-4-ethylphenol, 2,6-di-tert-butyl-4-n-butylphenol, 2,6-di-tert-butyl-4-isobutylphenol, 2,6-dicyclopentyl-4-methylphenol, 2-(a- methylcyclohexyl)-4,6-dimethylphenol, 2,6-dioctadecyl-4-methylphenol, 2,4,6- tricyclohexylphenol, 2,6-di-tert-butyl-4-methoxymethylphenol, nonylphenols which are linear or branched in the side chains, for example, 2,6-di-nonyl-4-methylphenol, 2,4- dimethyl-6-(1 '-methylundec-1 '-yl)phenol, 2,4-dimethyl-6-(1 '-methylheptadec-1 '- yl)phenol, 2,4-dimethyl-6-(1 '-methylpentadec-1 '-yl)phenol, 2,4-dimethyl-6-(1 '- methyltridec-1 '-yl)phenol and mixtures thereof. 1 .2. Alkylthiomethylphenols, for example 2,4-dioctylthiomethyl-6-tert-butylphenol, 2,4- dioctylthiomethyl-6-methylphenol, 2,4-dioctylthiomethyl-6-ethylphenol, 2,6-di- dodecylthiomethyl-4-nonylphenol.

1 .3. Hydroquinones and alkylated hydroquinones, for example 2,6-di-tert-butyl-4- methoxyphenol, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, 2,6- diphenyl-4-octadecyloxyphenol, 2,6-di-tert-butylhydroquinone, 2 , 5-d i-tert-butyl-4- hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyanisole, 3,5-di-tert-butyl-4-hydroxyphenyl stearate, bis(3,5-di-tert-butyl-4-hydroxyphenyl) adipate.

1 .4. Tocopherols, for example a-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol and mixtures thereof (vitamin E). 1 .5. Hydroxylated thiodiphenyl ethers, for example 2,2'-thiobis(6-tert-butyl-4- methylphenol), 2,2'-thiobis(4-octylphenol), 4,4'-thiobis(6-tert-butyl-3-methylphenol), 4,4'-thiobis(6-tert-butyl-2-methylphenol), 4,4'-thiobis(3,6-di-sec-amylphenol), 4,4'- bis(2,6-dimethyl-4-hydroxyphenyl)disulfide. 1 .6. Alkylidenebisphenols, for example 2,2'-methylenebis(6-tert-butyl-4-methylphenol), 2,2'-methylenebis(6-tert-butyl-4-ethylphenol), 2,2'-methylenebis[4-methyl-6-(a- methylcyclohexyl)phenol], 2,2'-methylenebis(4-methyl-6-cyclohexylphenol), 2,2'- methylenebis(6-nonyl-4-methylphenol), 2,2'-methylenebis(4,6-di-tert-butylphenol), 2,2'- ethylidenebis(4,6-di-tert-butylphenol), 2,2'-ethylidenebis(6-tert-butyl-4-isobutylphenol), 2,2'-methylenebis[6-(a-methylbenzyl)-4-nonylphenol], 2,2'-methylenebis[6-(a,a- dimethylbenzyl)-4-nonylphenol], 4,4'-methylenebis(2,6-di-tert-butylphenol), 4,4'- methylenebis(6-tert-butyl-2-methylphenol), 1 ,1 -bis(5-tert-butyl-4-hydroxy-2- methylphenyl)butane, 2,6-bis(3-tert-butyl-5-methyl-2-hydroxybenzyl)-4-methylpheno l, 1 ,1 ,3-tris(5-tert-butyl-4-hydroxy-2-methylphenyl)butane, 1 ,1 -bis(5-tert-butyl-4-hydroxy- 2-methyl-phenyl)-3-n-dodecylmercaptobutane, ethylene glycol bis[3,3-bis(3'-tert-butyl- 4'-hydroxyphenyl)butyrate], bis(3-tert-butyl-4-hydroxy-5-methyl-phenyl)dicyclopenta- diene, bis[2-(3'-tert-butyl-2'-hydroxy-5'-methylbenzyl)-6-tert-buty l-4- methylphenyl]terephthalate, 1 ,1 -bis-(3,5-dimethyl-2-hydroxyphenyl)butane, 2,2-bis(3,5- di-tert-butyl-4-hydroxyphenyl)propane, 2,2-bis(5-tert-butyl-4-hydroxy2-methylphenyl)-4- n-dodecylmercaptobutane, 1 ,1 ,5,5-tetra-(5-tert-butyl-4-hydroxy-2- methylphenyl)pentane.

1 .7. 0-, N- and S-benzyl compounds, for example 3,5,3',5'-tetra-tert-butyl-4,4'- dihydroxydibenzyl ether, octadecyl-4-hydroxy-3,5-dimethylbenzylmercaptoacetate, tridecyl-4-hydroxy-3,5-di-tert-butylbenzylmercaptoacetate, tris(3,5-di-tert-butyl-4- hydroxybenzyl)amine, bis(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)dithioterephth alate, bis(3,5-di-tert-butyl-4-hydroxybenzyl)sulfide, isooctyl-3,5-di-tert-butyl-4- hyd roxybenzyl m erca ptoacetate .

1 .8. Hydroxybenzylated malonates, for example dioctadecyl-2,2-bis(3,5-di-tert-butyl-2- hydroxybenzyl)malonate, di-octadecyl-2-(3-tert-butyl-4-hydroxy-5- methylbenzyl)malonate, di-dodecylmercaptoethyl-2,2-bis (3 , 5-d i-te rt-butyl-4- hydroxybenzyl) malonate, bis[4-(1 ,1 ,3,3-tetramethylbutyl)phenyl]-2,2-bis(3,5-di-tert- butyl-4-hydroxybenzyl)malonate.

1 .9. Aromatic hydroxybenzyl compounds, for example 1 ,3,5-tris(3,5-di-tert-butyl-4- hydroxybenzyl)-2,4,6-trimethylbenzene, 1 ,4-bis(3,5-di-tert-butyl-4-hydroxybenzyl)-

2,3,5,6-tetramethylbenzene, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)phenol.

1 .10. Triazine compounds, for example 2,4-bis(octylmercapto)-6-(3,5-di-tert-butyl-4- hydroxyanilino)-1 ,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4- hydroxyanilino)-1 ,3,5-triazine, 2-octylmercapto-4,6-bis(3,5-di-tert-butyl-4- hydroxyphenoxy)-1 ,3,5-triazine, 2,4,6-tris(3,5-di-tert-butyl-4-hydroxyphenoxy)-1 ,2,3- triazine, 1 ,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanurate, 1 ,3,5-tris(4-tert-butyl- 3-hydroxy-2,6-dimethylbenzyl)isocyanurate, 2,4,6-tris(3,5-di-tert-butyl-4- hydroxyphenylethyl)-1 ,3,5-triazine, 1 ,3,5-tris(3,5-di-tert-butyl-4-hydroxy- phenylpropionyl)-hexahydro-1 ,3,5-triazine, 1 ,3,5-tris(3,5-dicyclohexyl-4- hydroxybenzyl)isocyanurate.

1 .1 1. Benzylphosphonates, for example dimethyl-2,5-di-tert-butyl-4- hydroxybenzylphosphonate, diethyl-3,5-di-tert-butyl-4-hydroxybenzylphosphonate, di- octadecyl3,5-di-tert-butyl-4-hydroxybenzylphosphonate, dioctadecyl-5-tert-butyl-4- hydroxy-3-methylbenzylphosphonate, the calcium salt of the monoethyl ester of 3,5-di- tert-butyl-4-hydroxybenzylphosphonic acid. 1 .12. Acylaminophenols, for example 4-hydroxylauranilide, 4-hydroxystearanilide, octyl N-(3,5-di-tert-butyl-4-hydroxyphenyl)carbamate.

1 .13. Esters of -(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid with mono- or poly- hydric alcohols, e.g. with methanol, ethanol, n-octanol, i-octanol, octadecanol, 1 ,6- hexanediol, 1 ,9-nonanediol, ethylene glycol, 1 ,2-propanediol, neopentyl glycol, thiodi- ethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3- thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1 - phospha-2,6,7-trioxabicyclo[2.2.2]octane.

1 .14. Esters of -(5-tert-butyl-4-hydroxy-3-methylphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, n-octanol, i-octanol, octadecanol, 1 ,6- hexanediol, 1 ,9-nonanediol, ethylene glycol, 1 ,2-propanediol, neopentyl glycol, thiodi- ethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3- thiapentadecanol, trimethylhexanediol, trimethylolpropane, 4-hydroxymethyl-1 - phospha-2,6,7-trioxabicyclo[2.2.2]octane; 3,9-bis[2-{3-(3-tert-butyl-4-hydroxy-5- methylphenyl)propionyloxy}-1 ,1 -dimethylethyl]-2,4,8,10-tetraoxaspiro[5.5]undecane.

1 .15. Esters of -(3,5-dicyclohexyl-4-hydroxyphenyl)propionic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol, octadecanol, 1 ,6-hexanediol, 1 ,9- nonanediol, ethylene glycol, 1 ,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhex- anediol, trimethylolpropane, 4-hydroxymethyl-1 -phospha-2,6,7- trioxabicyclo[2.2.2]octane. 1 .16. Esters of 3,5-di-tert-butyl-4-hydroxyphenyl acetic acid with mono- or polyhydric alcohols, e.g. with methanol, ethanol, octanol, octadecanol, 1 ,6-hexanediol, 1 ,9- nonanediol, ethylene glycol, 1 ,2-propanediol, neopentyl glycol, thiodiethylene glycol, diethylene glycol, triethylene glycol, pentaerythritol, tris(hydroxyethyl)isocyanurate, N,N'-bis(hydroxyethyl)oxamide, 3-thiaundecanol, 3-thiapentadecanol, trimethylhex- anediol, trimethylolpropane, 4-hydroxymethyl-1 -phospha-2,6,7- trioxabicyclo[2.2.2]octane.

1 .17. Amides of -(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid e.g. N,N'-bis(3,5-di- tert-butyl-4-hydroxyphenylpropionyl)hexamethylenediamide, N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)trimethylenediamide, N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)hydrazide, N,N'-bis[2-(3-[3,5-di-tert-butyl-4- hydroxyphenyl]propionyloxy)ethyl]oxamide (Naugard ^® XL-1 , supplied by Uniroyal).

1 .18. Aminic antioxidants, for example N,N'-di-isopropyl-p-phenylenediamine, N,N'-di- sec-butyl-p-phenylenediamine, N,N'-bis(1 ,4-dimethylpentyl)-p-phenylenediamine, Ν,Ν'- bis(1 -ethyl-3-methylpentyl)-p-phenylenediamine, N,N'-bis(1 -methylheptyl)-p- phenylenediamine, N,N'-dicyclohexyl-p-phenylenediamine, N,N'-diphenyl-p- phenylenediamine, N,N'-bis(2-naphthyl)-p-phenylenediamine, N-isopropyl-N'-phenyl-p- phenylenediamine, N-(1 ,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine, N-(1 - methylheptyl)-N'-phenyl-p-phenylenediamine, N-cyclohexyl-N'-phenyl-p- phenylenediamine, 4-(p-toluenesulfamoyl)diphenylamine, N,N'-dimethyl-N,N'-di-sec- butyl-p-phenylenediamine, diphenylamine, N-allyldiphenylamine, 4-isopropoxydiphenyl- amine, N-phenyl-1 -naphthylamine, N-(4-tert-octylphenyl)-1 -naphthylamine, N-phenyl-2- naphthylamine, octylated diphenylamine, for example p,p'-di-tert-octyldiphenylamine, 4- n-butylaminophenol, 4-butyrylaminophenol, 4-nonanoylaminophenol, 4- dodecanoylaminophenol, 4-octadecanoylaminophenol, bis(4-methoxyphenyl)amine, 2,6-di-tert-butyl-4-dimethylaminomethylphenol, 2,4'-diaminodiphenylmethane, 4,4'- diaminodiphenylmethane, N,N,N',N'-tetramethyl-4,4'-diaminodiphenylmethane, 1 ,2- bis[(2-methylphenyl)amino]ethane, 1 ,2-bis(phenylamino)propane, (o-tolyl)biguanide, bis[4-(1 ',3'-dimethylbutyl)phenyl]amine, tert-octylated N-phenyl-1 -naphthylamine, a mixture of mono- and dialkylated tert-butyl/tert-octyldiphenylamines, a mixture of mono- and dialkylated nonyldiphenylamines, a mixture of mono- and dialkylated dodecyldi- phenylamines, a mixture of mono- and dialkylated isopropyl/isohexyldiphenylamines, a mixture of mono- and dialkylated tert-butyldiphenylamines, 2,3-dihydro-3,3-dimethyl- 4H-1 ,4-benzothiazine, phenothiazine, a mixture of mono- and dialkylated tert-butyl/tert- octylphenothiazines, a mixture of mono- and dialkylated tert-octyl-phenothiazines, N- allylphenothiazine, N,N,N',N'-tetraphenyl-1 ,4-diaminobut-2-ene.

2. UV absorbers and light stabilizers

2.1 . 2-(2'-Hydroxyphenyl)benzotriazoles, for example 2-(2'-hydroxy-5'-methylphenyl)- benzotriazole, 2-(3',5'-di-tert-butyl-2'-hydroxyphenyl)benzotriazole, 2-(5'-tert-butyl-2'- hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-5'-(1 ,1 ,3,3- tetramethylbutyl)phenyl)benzotriazole, 2-(3\5'-di-tert-butyl-2'-hydroxyphenyl)-5-chloro- benzotriazole, 2-(3'-tert-butyl-2'-hydroxy-5'-methylphenyl)-5-chloro-benzot riazole, 2-(3'- sec-butyl-5'-tert-butyl-2'-hydroxyphenyl)benzotriazole, 2-(2'-hydroxy-4'- octyloxyphenyl)benzotriazole, 2-(3\5'-di-tert-amyl-2'-hydroxyphenyl)benzotriazole, 2- (3',5'-bis-(a,a-dimethylbenzyl)-2'-hydroxyphenyl)benzotriazo le, 2-(3'-tert-butyl-2'- hydroxy-5'-(2-octyloxycarbonylethyl)phenyl)-5-chloro-benzotr iazole, 2-(3'-tert-butyl-5'- [2-(2-ethylhexyloxy)-carbonylethyl]-2'-hydroxyphenyl)-5-chlo ro-benzotriazole, 2-(3'-tert- butyl-2'-hydroxy-5'-(2-methoxycarbonylethyl)phenyl)-5-chloro -benzotriazole, 2-(3'-tert- butyl-2'-hydroxy-5'-(2-methoxycarbonylethyl)phenyl)benzotnaz ole, 2-(3'-tert-butyl-2'- hydroxy-5'-(2-octyloxycarbonylethyl)phenyl)benzotriazole, 2-(3'-tert-butyl-5'-[2-(2- ethylhexyloxy)carbonylethyl]-2'-hydroxyphenyl)benzotriazole, 2-(3'-dodecyl-2'-hydroxy- 5'-methylphenyl)benzotriazole, 2-(3'-tert-butyl-2'-hydroxy-5'-(2- isooctyloxycarbonylethyl)phenylbenzotriazole, 2,2'-methylene-bis[4-(1 , 1 ,3,3- tetramethylbutyl)-6-benzotriazole-2-ylphenol]; the transesterification product of 2-[3'- tert-butyl-5'-(2-methoxycarbonylethyl)-2'-hydroxyphenyl]-2H- benzotriazole with polyethylene glycol 300; [R- CH ₂ CH ₂ — COO - CH ₂ CH ₂ -^ , where R = 3'-tert-butyl-4'- hydroxy-5'-2H-benzotriazol-2-ylphenyl, 2-[2'-hydroxy-3'-(a,a-dimethylbenzyl)-5'- (1 , 1 ,3,3-tetramethylbutyl)-phenyl]benzotriazole; 2-[2'-hydroxy-3'-(1 , 1 ,3,3- tetramethylbutyl)-5'-(a,a-dimethylbenzyl)-phenyl]benzotriazo le.

2.2. 2-Hydroxybenzophenones, for example the 4-hydroxy, 4-methoxy, 4-octyloxy, 4- decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2',4'-trihydroxy and 2'-hydroxy-4,4'-dimethoxy derivatives. 2.3. Esters of substituted and unsubstituted benzoic acids, for example 4-tert-butyl- phenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoyl resorcinol, bis(4- tert-butylbenzoyl)resorcinol, benzoyl resorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl- 4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl 3,5-di- tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl 3 , 5-d i-tert-butyl-4- hydroxybenzoate.

2.4. Acrylates, for example ethyl a-cyano-p,p-diphenylacrylate, isooctyl a-cyano-β,β- diphenylacrylate, methyl a-carbomethoxycinnamate, methyl a-cyano-p-methyl-p- methoxycinnamate, butyl a-cyano-p-methyl-p-methoxy-cinnamate, methyl a- carbomethoxy-p-methoxycinnamate, N-(p-carbomethoxy-p-cyanovinyl)-2- methylindoline, neopentyl tetra(a-cyano-p,p-diphenylacrylate. 2.5. Sterically hindered amines, for example 1 ,6-Hexanediamine N, N'-bis(1 -propyloxy- 2,2,6,6-tetramethyl-4-piperidinyl)- N, N'-bis-2-[4,5-bis-(N-n-butyl-N'-1 -propyloxy-2,2,6,6- tetramethyl-4-piperidinyl)-1 ,3,5-triazine], 1 ,6-Hexanediamine N, N'-bis(2, 2,6,6- tetramethyl-4-piperidinyl)- N, N'-bis-2-[4,5-bis-(N-n-butyl-N'-2,2,6,6-tetramethyl-4- piperidinyl)-1 ,3,5-triazine], carbonic acid bis(1 -undecyloxy-2,2,6,6-tetramethyl-4- piperidyl)ester, bis(2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(2,2,6,6-tetramethyl-4- piperidyl)succinate, bis(1 ,2,2,6,6-pentamethyl-4-piperidyl)sebacate, bis(1 -octyloxy- 2,2,6,6-tetramethyl-4-piperidyl)sebacate, bis(1 ,2,2,6,6-pentamethyl-4-piperidyl) n-butyl- 3,5-di-tert-butyl-4-hydroxybenzylmalonate, the condensate of 1 -(2-hydroxyethyl)- 2,2,6,6-tetramethyl-4-hydroxypiperidine and succinic acid, linear or cyclic condensates of N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexamethylenediamin e and 4-tert- octylamino-2,6-dichloro-1 ,3,5-triazine, tris(2,2,6,6-tetramethyl-4- piperidyl)nitrilotriacetate, tetrakis(2,2,6,6-tetramethyl-4-piperidyl)-1 ,2,3,4- butanetetracarboxylate, 1 ,1 '-(1 ,2-ethanediyl)-bis(3,3,5,5-tetramethylpiperazinone), 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-tert-b utylbenzyl)- malonate, 3-n-octyl-7,7,9,9-tetramethyl-1 ,3,8-triazaspiro[4.5]decane-2,4-dione, bis(1 - octyloxy-2,2,6,6-tetramethylpiperidyl)sebacate, bis(1 -octyloxy-2, 2,6,6- tetramethylpiperidyl)succinate, linear or cyclic condensates of N,N'-bis(2,2,6,6- tetramethyl-4-piperidyl)hexamethylenediamine and 4-morpholino-2,6-dichloro-1 ,3,5- triazine, the condensate of 2-chloro-4, 6-bis(4-n-butylamino-2, 2,6,6- tetramethylpiperidyl)-1 ,3,5-triazine and 1 ,2-bis(3-aminopropylamino)ethane, the condensate of 2-chloro-4,6-di-(4-n-butylamino-1 ,2,2,6,6-pentamethylpiperidyl)-1 ,3,5- triazine and 1 ,2-bis(3-aminopropylamino)ethane, 8-acetyl-3-dodecyl-7,7,9,9-tetrame- thyl-1 ,3,8-triazaspiro[4.5]decane-2,4-dione, 3-dodecyl-1 -(2,2,6,6-tetramethyl-4- piperidyl)pyrrolidine-2,5-dione, 3-dodecyl-1 -(1 ,2,2,6,6-pentamethyl-4- piperidyl)pyrrolidine-2,5-dione, a mixture of 4-hexadecyloxy- and 4-stearyloxy-2,2,6,6- tetramethylpiperidine, a condensate of N,N'-bis(2,2,6,6-tetramethyl-4- piperidyl)hexamethylenediamine and 4-cyclohexylamino-2,6-dichloro-1 ,3,5-triazine, a condensate of 1 ,2-bis(3-aminopropylamino)ethane and 2, 4, 6-trichloro-1 ,3,5-triazine as well as 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No. [136504-96-6]); a condensate of 1 ,6-hexanediamine and 2, 4, 6-trichloro-1 ,3,5-triazine as well as N,N- dibutylamine and 4-butylamino-2,2,6,6-tetramethylpiperidine (CAS Reg. No. [192268- 64-7]); N-(2,2,6,6-tetramethyl-4-piperidyl)-n-dodecylsuccinimide, N-(1 ,2,2,6,6- pentamethyl-4-piperidyl)-n-dodecylsuccinimide, 2-undecyl-7,7,9,9-tetramethyl-1 -oxa- 3,8-diaza-4-oxo-spiro[4,5]decane, a reaction product of 7,7,9,9-tetramethyl-2- cycloundecyl-1 -oxa-3,8-diaza-4-oxospiro-[4,5]decane and epichlorohydrin, 1 ,1 - bis(1 ,2,2,6,6-pentamethyl-4-piperidyloxycarbonyl)-2-(4-methoxyphe nyl)ethene, Ν,Ν'- bis-formyl-N,N'-bis(2,2,6,6-tetramethyl-4-piperidyl)hexameth ylenediamine, a diester of 4-methoxymethylenemalonic acid with 1 ,2,2,6, 6-pentamethyl-4-hydroxypiperidine, poly[methylpropyl-3-oxy-4-(2,2,6,6-tetramethyl-4-piperidyl)] siloxane, a reaction product of maleic acid anhydride-a-olefin copolymer with 2,2,6,6-tetramethyl-4-aminopiperidine or 1 ,2,2,6,6-pentamethyl-4-aminopiperidine, 2,4-bis[N-(1 -cyclohexyloxy-2,2,6,6- tetramethylpiperidine-4-yl)-N-butylamino]-6-(2-hydroxyethyl) amino-1 ,3,5-triazine, 1 -(2- hydroxy-2-methylpropoxy)-4-octadecanoyloxy-2,2,6,6-tetrameth ylpiperidine, 5-(2- ethylhexanoyl)oxymethyl-3,3,5-trimethyl-2-morpholinone, Sanduvor (Clariant; CAS Reg. No. 106917-31 -1 ], 5-(2-ethylhexanoyl)oxymethyl-3,3,5-trimethyl-2-morpholinone, the reaction product of 2,4-bis[(1 -cyclohexyloxy-2,2,6,6-piperidine-4-yl)butylamino]-6- chloro-s-triazine with N,N'-bis(3-aminopropyl)ethylenediamine), 1 ,3,5-tris(N-cyclohexyl- N-(2,2,6,6-tetramethylpiperazine-3-one-4-yl)amino)-s-triazin e, 1 ,3,5-tris(N-cyclohexyl- N-(1 ,2,2,6,6-pentamethylpiperazine-3-one-4-yl)amino)-s-triazine,

2.6 Benzoxazinone derivatives such as e.g. 2,2'-(1 ,4-phenylene)bis[4H-3,1 - benzoxazin-4-one] (CAS No. 018600-59-4).

2.7. Oxamides, for example 4,4'-dioctyloxyoxanilide, 2,2'-diethoxyoxanilide, 2,2'- dioctyloxy-5,5'-di-tert-butoxanilide, 2,2'-didodecyloxy-5,5'-di-tert-butoxanilide, 2-ethoxy-

2'-ethyloxanilide, N,N'-bis(3-dimethylaminopropyl)oxamide, 2-ethoxy-5-tert-butyl-2'- ethoxanilide and its mixture with 2-ethoxy-2'-ethyl-5,4'-di-tert-butoxanilide, mixtures of o- and p-methoxy-disubstituted oxanilides and mixtures of o- and p-ethoxy- disubstituted oxanilides.

2.8. 2-(2-Hydroxyphenyl)-1 ,3,5-triazines, 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-octyloxyphenyl)-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-tridecyloxyphenyl)-4,6-bis(2,4-dimethylphenyl)-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, 2-[4- (dodecyloxy/tridecyloxy-2-hydroxypropoxy)-2-hydroxyphenyl]-4 ,6-bis(2,4- dimethylphenyl)-1 ,3,5-triazine, 2-[2-hydroxy-4-(2-hydroxy-3- dodecyloxypropoxy)phenyl]-4,6-bis(2,4-dimethylphenyl)-1 ,3,5-triazine, 2-(2-hydroxy-4- hexyloxy)phenyl-4,6-diphenyl-1 ,3,5-triazine, 2-(2-hydroxy-4-methoxyphenyl)-4,6- diphenyl-1 ,3,5-triazine, 2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropoxy)phenyl]- 1 ,3,5-triazine, 2-(2-hydroxyphenyl)-4-(4-methoxyphenyl)-6-phenyl-1 ,3,5-triazine, 2-{2- hydroxy-4-[3-(2-ethylhexyl-1 -oxy)-2-hydroxypropyloxy]phenyl}-4,6-bis(2,4-di- methylphenyl)-1 ,3,5-triazine, 2,4-bis(4-[2-ethylhexyloxy]-2-hydroxyphenyl)-6-(4- methoxyphenyl)-1 ,3,5-triazine, 2-(4,6-bis-biphenyl-4-yl-1 ,3,5-triazin-2-yl)-5-(2-ethyl-(n)- hexyloxy)phenol.

3. Metal deactivators, for example Ν,Ν'-diphenyloxamide, N-salicylal-N'-salicyloyl hydrazine, N,N'-bis(salicyloyl)hydrazine, N,N'-bis(3,5-di-tert-butyl-4- hydroxyphenylpropionyl)hydrazine, 3-salicyloylamino-1 ,2,4-triazole, bis(benzylidene)oxalyl dihydrazide, oxanilide, isophthaloyl dihydrazide, sebacoyl bi- sphenylhydrazide, Ν,Ν'-diacetyladipoyl dihydrazide, N,N'-bis(salicyloyl)oxalyl dihydrazide, N,N'-bis(salicyloyl)thiopropionyl dihydrazide.

3a. Formamidines, for example Ethoxycarbonylphenyl)-N'-ethyl-N'-phenyl formamidine.

4. Phosphites and phosphonites, for example triphenyl phosphite, diphenylalkyl phosphites, phenyldialkyl phosphites, tris(nonylphenyl) phosphite, trilauryl phosphite, trioc- tadecyl phosphite, distearylpentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite, diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert- butylphenyl)pentaerythritol diphosphite, bis(2,4-di-cumylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, diisodecyloxy- pentaerythritol diphosphite, bis(2,4-di-tert-butyl-6-methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tris(tert-butylphenyl)pentaerythritol diphosphite, tristearyl sorbitol tri- phosphite, tetrakis(2,4-di-tert-butylphenyl) 4,4'-biphenylene diphosphonite, [3, 3', 5,5'- tetra-tert. butyl-1 ,1 'biphenyl-2,2'-diyl]-[ 3-(3-methyl-4-hydroxy-5-tert.butyl-phenyl)- propyl]-phosphite, 6-isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz[d,g]-1 ,3,2- dioxaphosphocin, bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite, bis(2,4-di-tert- butyl-6-methylphenyl)ethyl phosphite, tris-[4-tert. butyl-2-(5-tert. butyl-3H-1 -benzofuran- 2-one)-phenyl]-phosphite, tris-[4-(1 ,1 '3,3'-tetramethyl-butane)-2-(5-(1 ,1 '3,3'- tetramethyl-butane-3H-1 -benzofuran-2-one)-phenyl]-phosphite, tris-[2,6-dimethyl-(5,7- di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]-phosphite, bis-[2,6-dimethyl-(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]-phenyl-phosphite, bis-[2,6-dimethyl-(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]-[2,4-di-tert. butyl-phenyl]-phosphite, [3,3',5,5'- tetra-tert. butyl-1 , 1 'biphenyl-2,2'-diyl]-[4-tert. butyl-(5-tert. butyl)-3H-1 -benzofuran-2- one)-phenyl]-phosphite, [3,3',5,5'-tetra-tert. butyl-1 ,1 'biphenyl-2,2'-diyl]-[ 2,6-dimethyl- (5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]-phosphite, [2,2'-methylene-bis-(4,6- di-tert. butyl-phenyl)-1 ,1 '-diyl]-[1 ,6-dimethyl-4-(5,7-di-tert. butyl)-3H-1 -benzofuran-2- one)-phenyl]-phosphite, [2,2'-ethylene-bis-(4,6-di-tert. butyl-phenyl)-1 ,1 '-diyl]-[1 ,6- dimethyl-4-(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]-phosphite, [2,2'- ethylene-bis-(4,6-di-tert. butyl-phenyl)-1 ,1 '-diyl]-[1 -methyl-6-tert. butyl-4-(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenyl]-phosphite, bis-(2,6-dimethyl-(5,7-di-tert. butyl)- 3H-1 -benzofuran-2-one)-phenol) pentaerythritol diphosphite, bis-(1 -methyl-6-tert. butyl -(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)-phenol) pentaerythritol diphosphite, bis-(4- tert. butyl -(5-tert. butyl)-3H-1 -benzofuran-2-one)-phenol) pentaerythritol diphosphite, bis-(4-(1 , 1 '3,3'-tetramethyl-butane)-(5-(1 , 1 '3,3'-tetramethyl-butane))-3H-1 -benzofuran- 2-one)-phenol) pentaerythritol diphosphite, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl- dibenz[d,g]-1 ,3,2-dioxaphosphocin, 2,2',2"-nitrilo[triethyltris(3,3',5,5'-tetra-tert-butyl-1 ,1 '- biphenyl-2,2'-diyl)phosphite], 2-ethylhexyl(3,3',5,5'-tetra-tert-butyl-1 ,1 '-biphenyl-2,2'- diyl)phosphite, 5-butyl-5-ethyl-2-(2,4,6-tri-tert-butylphenoxy)-1 ,3,2-dioxaphosphirane.

The following phosphites are especially preferred:

Tris(2,4-di-tert-butylphenyl) phosphite (lrgafos ^® 168, Ciba Specialty Chemicals Inc.), tris(nonylphenyl) phosphite, phosphorus acid mixed 2,4-bis(1 ,1 -dimethylpropyl)phenyl and 4-(1 ,1 -dimethylpropyl)phenyl triesters (CAS Reg. No. 939402-02-5), phosphorous acid triphenyl ester polymer with alpha-hydro-omega-hydroxypoly[oxy(methyl-1 ,2- ethanediyl) C10-16 alkyl esters (CAS Reg. No. 1227937-46-3).

[2,2'-ethylene-bis-(4,6-di-tert. butyl-phenyl)-1 ,1 '-diyl]-[1 ,6-dimethyl-4-(5,7-di-tert. butyl)- 3H-1 -benzofuran-2-one)-phenyl]-phosphite, [2,2'-ethylene-bis-(4,6-di-tert. butyl- phenyl)-1 ,1 '-diyl]-[1 -methyl-6-tert. butyl-4-(5,7-di-tert. butyl)-3H-1 -benzofuran-2-one)- phenyl]-phosphite, [3,3',5,5'-tetra-tert. butyl-1 ,1 'biphenyl-2,2'-diyl]-[ 3-(3-methyl-4- hydroxy-5-tert.butyl-phenyl)-propyl]-phosphite.

5. Hydroxylamines, for example N,N-dibenzylhydroxylamine, N,N- diethylhydroxylamine, Ν,Ν-dioctylhydroxylamine, N,N-dilaurylhydroxylamine, N,N- ditetradecylhydroxylamine, N,N-dihexadecylhydroxylamine, N,N- dioctadecylhydroxylamine, N-hexadecyl-N-octadecylhydroxylamine, N-heptadecyl-N- octadecylhydroxylamine, Ν,Ν-dialkylhydroxylamine derived from hydrogenated tallow amine. 6. Amine oxides, for example Ν,Ν-dibenzylhydroxylamine oxide, N,N- diethylhydroxylamine oxide, Ν,Ν-dioctylhydroxylamine oxide, N,N- dilaurylhydroxylamine oxide, Ν,Ν-ditetradecylhydroxylamine oxide, N,N- dihexadecylhydroxylamine oxide, Ν,Ν-dioctadecylhydroxylamine oxide, N-hexadecyl-N- octadecylhydrox-ylamine oxide, N-heptadecyl-N-octadecylhydroxylamine oxide, N,N- dialkylhydroxylamine oxide derived from hydrogenated tallow amine.

7. Nitrones, for example, N-benzyl-alpha-phenylnitrone, N-ethyl-alpha-methylnitrone,

N-octyl-alpha-heptylnitrone, N-lauryl-alpha-undecylnitrone, N-tetradecyl-alpha- tridecylnnitrone, N-hexadecyl-alpha-pentadecylnitrone, N-octadecyl-alpha- heptadecylnitrone, N-hexadecyl-alpha-heptadecylnitrone, N-ocatadecyl-alpha- pentadecylnitrone, N-heptadecyl-alpha-heptadecylnitrone, N-octadecyl-alpha- hexadecylnitrone, nitrone derived from Ν,Ν-dialkylhydroxylamine derived from hydrogenated tallow amine. 8. Thiosynergists, for example dilauryl thiodipropionate, dimistryl thiodipropionate, distearyl thiodipropionate, pentaerythritol tetrakis[3-(dodecylthio)propionate] or distearyl disulfide. 9. Peroxide scavengers, for example esters of β-thiodipropionic acid, for example the lauryl, stearyl, myristyl or tridecyl esters, mercaptobenzimidazole or the zinc salt of 2- mercaptobenzimidazole, zinc dibutyldithiocarbamate, dioctadecyl disulfide, pentaeryth- ritol tetrakis(p-dodecylmercapto)propionate.

10. Basic co-stabilizers, for example melamine, polyvinylpyrrolidone, dicyandiamide, triallyl cyanurate, urea derivatives, hydrazine derivatives, amines, polyamides, polyure- thanes, alkali metal salts and alkaline earth metal salts of higher fatty acids, for example calcium stearate, zinc stearate, magnesium behenate, magnesium stearate, sodi- urn ricinoleate and potassium palmitate, antimony pyrocatecholate or zinc pyrocate- cholate, zeolithes, hydrotalcites, hydrocalumites.

1 1 . Nucleating agents, for example inorganic substances, such as talcum, metal oxides, such as titanium dioxide or magnesium oxide, phosphates, carbonates or sulfates of, preferably, alkaline earth metals; organic compounds, such as mono- or polycar- boxylic acids and the salts thereof, e.g. 4-tert-butyl benzoic acid, adipic acid, diphenyla- cetic acid, sodium succinate or sodium benzoate; polymeric compounds, such as ionic copolymers (ionomers). Especially preferred are 1 ,3:2,4-bis(3',4'- dimethylbenzylidene)sorbitol, 1 ,3:2,4-di(paramethyldibenzylidene)sorbitol, and 1 ,3:2,4- di(benzylidene)sorbitol. Beta-nucleating agents are also of interest.

12. Fillers and reinforcing agents, for example calcium carbonate, silicates, glass fibres, carbon fibers, glass beads, asbestos, talcum (preferably with a particle size of 0.01 to 20 μηη), kaolin, mica, barium sulfate, metal oxides and hydroxides, carbon black, graphite, wood flour and flours or fibers of other natural products, synthetic fibers.

13. Other additives, for example plasticisers, lubricants, emulsifiers, pigments, rheology additives, catalysts, flow-control agents, optical brighteners, flameproofing agents, antistatic agents and blowing agents.

14. Benzofuranones and indolinones, for example those disclosed in U.S. 4,325,863; U.S. 4,338,244; U.S. 5,175,312; U.S. 5,216,052; U.S. 5,252,643; DE-A-431661 1 ;

DE-A-4316622; DE-A-4316876; EP-A-0589839, EP-A-0591 102; EP-A-1291384 or 3-[4- (2-acetoxyethoxy)phenyl]-5,7-di-tert-butylbenzofuran-2-one, 5,7-di-tert-butyl-3-[4-(2- stearoyloxyethoxy)phenyl]benzofuran-2-one, 3,3'-bis[5,7-di-tert-butyl-3-(4-[2- hydroxyethoxy]phenyl)benzofuran-2-one], 5,7-di-tert-butyl-3-(4- ethoxyphenyl)benzofuran-2-one, 3-(4-acetoxy-3,5-dimethylphenyl)-5,7-di-tert- butylbenzofuran-2-one, 3-(3,5-dimethyl-4-pivaloyloxyphenyl)-5,7-di-tert- butylbenzofuran-2-one, 3-(3,4-dimethylphenyl)-5,7-di-tert-butylbenzofuran-2-one, 3- (2,3-dimethylphenyl)-5,7-di-tert-butylbenzofuran-2-one, 3-(2-acetyl-5-isooctylphenyl)-5- isooctylbenzofuran-2-one. The conventional additive may be present in the polyethylene of the pipe according to the present invention in an amount of e.g. 0.001 to 10 %, relative to the weight of the polyethylene. A further embodiment of the present invention is the polyethylene pipe as defined above, which is in contact with chlorinated (common chlorinated water disinfectants such as chlorine (hypo-chlorite), chlorine dioxide and chloramines) or non-chlorinated water.

Another embodiment of the present invention is the use of a mixture containing components A) and B) in a weight ratio of 1 :10 to 10:1 for stabilizing a polyethylene pipe.

Still another embodiment of the present invention is a method for stabilizing a polyeth- ylene pipe which comprises incorporating into the polyethylene components A) and B) in a weight ratio of 1 :10 to 10:1.

The embodiments of the present invention include chlorinated or non-chlorinated water pipes for domestic, municipal or industrial applications, non-pressure up to high- pressure pipe applications used for drinkable or non-drinkable water, for general purpose water or waste water.

The examples below illustrate the invention in greater detail. All percentages and parts are by weight, unless stated otherwise.

Additives used on the following examples: lrganox ^® 1330:

(CAS number: 1709-70-2) 1 ,3,5-Tris(3,5-di-tert-butyl-4-hydroxybenzyl)-2,4,6-trimethyl benzene lrgafos ^® 168:

(CAS number: 31570-04-4)

Tris[2,4-di-tert-butylphenyl]phosphite

Sumilizer ^® GP:

(CAS number: 203255-81 -6)

6-[3-(3-tert-Butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,1 0-tetra-tert- butyldibenzo[d,f][1 ,3,2]dioxaphosphepin

Compound D-1 :

Compound (108) disclosed in Example S-8 of WO-A-2015/121445 [2,2'-Ethylene-bis-(4,6-di-tert. butyl-phenyl)-1 ,1 '-diyl]-[1 ,6-dimethyl-4(5,7-di-tert. butyl)- 3H-1 -benzofuran-2-one)-phenyl]-phosphite

Chimassorb ^® 2020:

(CAS number: 192268-64-7)

wherein Ei is and ai is a number from 2 to 10.

Hycite ^® 713:

(CAS number: 012304-65-3 or 1 1097-59-9)

Hydrotalcite (Magnesium aluminum hydroxide carbonate hydrate)

Examples:

Preparation of the test specimens: A mixture of a non-stabilised high density polyeth- ylene (HD-PE; Hostalen ^® CRP-100; natural classified under PE 100 of LyondellBasell; Melt Flow Rate: 190°C/5.0 Kg: 0.23g/10 min (ISO 1 133); Density: 0.95g/cm3 (ISO 1 183)) and the additives listed in Table 1 is mixed with a Mixaco Lab CM12 high speed mixer device. The obtained full formulation is then compounded on a Collin 25X42D extruder at 240°C and then injection molded on an Engel HL65 injection molding machine at 230°C. The injection molded plaques 40 mm x 60 mm x 2 mm are exposed to chlorinated water under the following parameters: 40°C, pH 7, 2 mg/L NaCIO and 50L/hours. The parameters measured are OIT Values using a DSC Q2000 von TA Instrument (Waters) at 200°C under O2 after 0, 3 and 5 months exposition. The depletion results are listed in Table 2.

Table 1 :

Table 2: Formulation

No. OIT at time zero OIT after 3 months OIT after 5 months

0 50 50 50

1 240 200 190

2 220 180 160

3 280 200 200

4 230 190 180

High OIT-values are desired.