CA1149534A - Stabilisation of acid catalysed stoving lacquers - Google Patents

Abstract

Abstract of the Disclosure Use of N-substituted 2,2,6,6-tetraalkylpiperidine compounds, their acid addition salts or complexes with metal compounds, optionally together with further stabilisers, for stabi-lising acid catalysed storing lacquers based on hot cross-linkable accrylic or alkyd resins against the action of light, moisture and oxygen.

Description

9~3~

Case 3-11768/C~S 20Q/+

Stabilisation of acid catalysed stoving lacquers The present invention is concerned with the stabil-ising of acid catalysed stoving lac~uers based on hot cross-linkable acrylic, polyester or alkyd resins against the action of light and moisture by the addition ofN-substituted polyalkylpiperidine derivatives, and with the stabilised acid catalysed stoving varnishes thereby obtained.
On occasion, but especially in retouching ~inishes and lacquers with a high solids content for use in industrial finishes, stovinglàcquer systems based on hot crosslinkable acrylic,polyester or alkyd resins are provided with an addit-ional acid catalyst. In this case, failure symptons caused by salt formation between light stabiliser and acid catalyst, delays in hardening, pigment flocculation, as well as a reduced light protective action, are observed. These problems can be solved in a satisfactory manner by means of the inven-tive use of ~-substituted polyalky]piperidine derivatives.
Accordingly, the present invention relates tO the use of N-substituted 2,2,6,6-tetraalkylpiperidine compounds, their acid addition salts or complexes with metal compounds, optionally together with further stabilisers for stabilising - - . --- . ,. . .. . ., .. , ~

, .:

53~L

acid catalysed stoving lacquers based on hot crosslinkable acrylic, polyester or alkyd resins, in particular acrylic or alkyd resins, against the action of light, moisture and oxygen.
The eligible N-substituted 2,2,6,6-tetraalXylpipe-ridine compounds of the invention are generally known and are already in use to prevent degradation by light. They are for example compounds which contain a group of the formula ~I) ~ 3 ~/
R - ~ (I) ~2 ~E3 or polymers, the recurring structural units ofwhich contain a group of the formula I or are linked through a bivalent group corresponding to ~he formula I, wherein Rlrepresents a free valency, and otherwise R represents hydrogen or methyl and Rl represents Cl-C18 alXyl, Cl-C6 hydroxyalkyl, 3 8 Y ' 3 C8 alkynyl, C7-C12 aralkyl which is unsub-stituted or substituted in the alkyl moiety by hydroxyl,or Cl-C8 alkanoyl or C3-C5 alkenoyl.
The following classes of compounds belong to the light stabilisers of the present invention:
a) light stabilisers of the for~ula (II) R~H2~,<R

. R~ 2 RCH2 Cd~ J

... ....... ..... ... .
:
'' .. ',~ :;

' ' '. , .

~ i34 wherein n is 1 to 4, preferably 1 or 2, R has the meaning given for the formula (I), Rl represents Cl-C18 alkyl, Cl-C6 hydroxy-alkyl, C3-C8 alkenyl, C3-C8 alkynyl, C7-C12 - aralkyl which is un-substituted or substituted in the alkyl moiety by hydroxyl, or represents Cl-C8 alkanoyl, C3-C5alkenoyl, preferably Cl-C12 alkyl, allyl, benzyl, acetyl, acryloyl, and R2 if n is 1, represents hydrogen, Cl-C12 alkyl, cyanoethyl, benzyl, glycidyl, a monovalent radical of a saturated or unsaturated aliphatic, cycloaliphatic, araliphatic or aromatic carboxylic acid, carbamic acid or phosphorus-containing acid or a monovalent silyl radical, preferably a radical of an aliphatic carboxylic acid containing 2 to 18 carbon atoms, of a cycloaliphatic carboxylic acid containing 5 to 12 carbon atoms or of an aromatic carboxylic acid containing 7 to 15 carbon atoms, and if n is 2, represents Cl-C12 alkylene, C4-C12 alkenylene, xylylene, a divalent radical of a saturated or unsaturated aliphatic, cycloaliphatic, araliphatic or aromatic dicarboxylic acid, dicarbamic acid or phosphorus-containing acid or a divalent silyl radical, preferably a radical of an aliphatic dicarboxylic acid containing 2 to 12 carbon atoms, a cycloali-phatic or aromatic dicarboxylic acid containing 8 to 14 carbonatoms, or of an aliphatic, cycloaliphatic or aromatic dicarbamic acid containing 8 to 14 carbon atoms, and, if n is 3, represents a trivalent radical of an aliphatic, cycloaliphatic or aromatic tricarboxylic acid, of an aromatic tricarbamic acid or of a phos-phorus-containing acid or a trivalent silyl radical, and if n is 4, represents a quadrivalent radical of an aliphatic, cyclo-aliphatic or aromatic tetracarboxylic acid.

S~

Cl-C12 alkyl is for example methyl, ethyl, n-propyl, n-butyl, sec-butyl, tert.-butyl, n-hexyl, n-octyl, 2-ethyl-hexyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl.

.
3a -,~ .

.
~ `

Rl as ~ 18 ai~yl can be for exal~ple the groups recited above and in addition, for example, n-tridecyl, n-tetradecyl, n-hexadecyl or n-oc.adecyl.
Rl as Cl~C6 hydroxyalkyl is in particular C1-C4-hydroxyalkyl and preferably 2-hydroxyethyl and 2-hydroxy-n-butyl.
Rl as C3-C8 alkenyl can be for example l-propenyl, allyl, methallyl, 2-butenyl, 2-pentenyl, 2-hexenyl,2-octenyl, 4-tert-butyl-2-butenyl.
Rl as C3-C8 a~inyl is preferably propargyl.
Rl as C7-C12 aralkyl is in particular phenethyl or, most preferably, benzyl, and, as aralkyl substituted in the alkyl moiety by hydroxyl, is in particular 2-hydroxyphen-ethyl.
Rl as Cl-C8 alkanoyl is for e~ample formyl, propion-yl, butyryl, octanoyl, but preferably acetyl, and, as C3-C5 alkenoyl, is in particular acryloyl.
R2 as a monovalent radical of a carboxylic acid is for example a radical of acetic acid, stearic acid, sali-cylic acid, methacrylic acid, benzoic acid or B-(3,5-di-tert-butyl-4-hydroxyphenyL)-propionic acid.
~ as a divalent radical of a dicarboxylic acid is for example a radical of ~aleic acid, adipic acid, suberic acid, 3ebacic acid, phthalic acid, dibutylmalonic acid, dibenzylmalonic acid or butyl-(3,5-di-tert-butyl-4-hydroxy-ben2yl)-malonic acid.
R2 as a trivalent radical of a tricarboxylic acid is for example a trimellitic acid radical.
R2 as a quadrivalent radical of a tetracarboxylic acid is for example a pyromellitic acid radical.
R2 as a divalent radical of a dicarbamic acid is for example a hexamethylenedicarbamic acid radicaL or a

2,~-toluylenedicarbamic acid radical.

.

c3s3 The following compounds are examples or polyalXyl-piperidine light stabilisers of this class:
1 4-hydroxy-1,2,2,6,6-pentamethylpiperidine 2 1-allyl-4-hydroxy-2,2,6,6-tetramethylpiperidine

3 1-benzyl-4-hydroxy-2,2,6,6-tetramethylpiperidine

4 1-(4-tert-butyl-2-~utenyl)-4-hydro.~y-2,2,6,o-tetramethylpiperidine l-ethyl-4-salicvloyloxy-2,2,6,6-tetrame~hyl-p i?eridine 6 4-me~hacryloylo~y-1,2,2,6,6-pentamethylpiperi-dine 7 1,2,2,6,6-pentamethylpiperidin - 4-yl-~-(3 "-di-tsrt.-butyl-4-hydroxy~henyl)-propion2t-8 1-benzyl-2,2,6,6-tetr~methyl-4-piperidinyl-maleinat~
9 di-~1,2,3,6-tetra~ethyl-2,6-diethyl~piperidLn-4-yl)-sebacate di-(1,2,2,6,6-pentamethyJpiperidin--4-yl)sebacate 11 di-(1-allyl-2,2,6,6-tetramethylpiperidin-4-yl)-sebacate 12 di-(1-allyl-2,2,6,6-tetramethyl-piperidin-4-yl)-phthalate 13 di-(1,2,2,6,6-pentamethylpiperidin-4-yl)-adipate 14 di-(1-allyl-2,2,6,6-tetramethylpiperidin-4-yl)-adipate lS l-propargyl-4-~-cyanoethvloxy-2,2,6,6-tet_-a-methyl-piperidine 16 1-acet~1-2,2,6,6-tetramethvlpiperidLn-4-yl-ace-t~t~
17 l-acsyloyL-4-~enzyloxy-2,2,6,6-t-tr2methyl?ipe-r idLne 18 di~utyl-di-(1,2,2,6,6-pentamethylplpericin-4-yl)-~alonate '; ', , ~ , . ;' ' ' ' ' . "
'' , .
. 1, ' ' ' ' ' ' '""" ' "':

l9 butyl-(3,5-di-tert-butyl-~-r.~7d_oxvbenzyl)-di-(1,2,2,6,6-pert~.~e~ylpi?er~din-~-yl)-.~alo~2_~
2'0 diDen~vi-di-(1,2,2,6,~-?enta~e~vl-?~?e~i~ir-1-yl)-malon2.~
21 dibenzyl-di-(1,2,3,6-tetra~etnyl-2,6-c-ethvl-pi?ericin-~-yl)-.~210nate 22 hexa~-1',5'-bis-(1-c:2r~æT.oy1o~ n-'Dutyl-2,2, 6,6-tetræmethyl?iperidine) 23 toluene-2',l'-bis-(~-car~oyloxy-i-n.-p-opyl 2,2,~,6-_etræ~e~l?i~eridine) 24 tris-(i-?~opvl-2,2,6;o-~e.ræ~e.hyi?i?e-i~ -.-~-~l)-?r.os?hi_e tris-(l-?ro?~1-2,2,6,6-_etrame-~l?~?e-i~ir.-~-yl - ~osDhate 26 phenyl-~bis-(1~2,2,6,6-pentamethylpiperidin-4-yl)]-phosphonate b) Light stabilisers of the formula (I~I) RCH ~ l3 . ~
C~ CH~ n wherein n is l or Z, R has the meaning given for formula (I), R1 has the meaning given in a) above, R3 represents Cl-Cl2 alkyl, C5-C7 cycloalkyl, C7-C8 aralkyl, C2-C18 alk-anoyl, C3-C5 alXenoyl, or benzoyl, and R4 if n is 1, re-presents Cl-C12 alkyl, C5-C7 cycloalkyl, C2-C8 alkenyl which is unsubstituted or substituted by a cyano, carbonyl or carba~ide group, glycidyl, a group of the formula -CH2-CH(OH)-Z or of the formula CONH-Z, wherein Z is ":
, .

~, ", ~ , .

53~

hydrogen, methyl or phenyl, and, if n is 2, represents C2-C12 alkylene, C6-C12 arylene, xylylene, a -C~2C~(OH)-CH2 group or a -CH2-CH (OH) -CH2-O-X-O-CH2-CH (OH) -CH2 group,wherein 2 C10 alkylene, C6-C15 arylene, C6-C cyc-loal.~ylene, or, with the proviso that R3 does nctrepresent alkynoyl, alkenoyl or benzoyl, R4 can also represent a di-valent radical of an aliphatic, cycloaliphatic or aromatic dicarboxylic acid or dicarbamic acid, or R3 and R4together, i~ n is 1, can be the cyclic radical of an aliphatic or aro-matic 1,2- or 1,3-dicarboxylic acid.
Substituents represented by Cl-C12 alkyl are those already derined ~n a) ~ o~e. C5-C7 cycloal~yl is in parti-cular cvclohexane. R3 as C7-C8 aralkyl is in particular phenethyl or, most prererably, benzyl. R3 as C2~C18alkanoy is ~or example propionyl, butyryl, octanoyl, dodecanoyl, hexadecanoyl, oc.adecanoyl, but prerera~ly ace.yl, and, as C3-C~ al.cenoyl, i~ in particular acryloyl.
R4 as C2-C8 alkenyl which is unsubstituted ~`~or substituted by a ~
cyano, carbonyl or carbamide group is for example l-pro-penyl, allyl, methallyl, 2-butenyl, 2-pentenyl, 2-hexenyl, 2-octenyl, 2,2-dicyano~inyl, 1-methyl-2-cyano-2-methoxy-carbonylvinyl, 2,2-diacetylaminovinyl.
C2-C12 alkylene is for example ethylene, propylene, 2,2-dlmethylpropylene, tetramethylene, hexamethylene, octa-methylene, decamethylene or dodecamethylene.
C6-C15 arylene is for example o-, m- or p-phenylene 1,4-naphthylene or 4,4'-dlphenylene.
X as C6-C12 cycloalkylene is in particular cyclo-hexylene.
The following compounds are examples of polyalkyl-piperidine light stabilisers of this class:

27 N,N'-bis-(1,2,2,6,6-pentamethylpi2eridin-4-yl)-hexamethylene-1,6-diacetamide 28 1-acetyl-4-(N-cyclohexylacetamido)-2,2,6,5-tetramethylpiperidine 29 The compound of the formula C~.~ C ~
CE~ ~2--~( GX)--CH2{) /\ A
CE3 C~3 CH3~--C~i~

C~ ?--C-.~-( CE)--C~ O
/ \ C '~
~ C~3 4 9 4-(di-2-hydroxyethyl)-amino-1,2,2,6,6-penta-methylpiperidine ~1 4-(di-2-hydroxyethyl)-am.ino-1-(2-hydroxyethyl)-2,2,6,6-tetramethylpiperidine 3Z 4-methacr~lamido-1,2,2,6,6 pentamethylpiperi-dine c) Light stabilisers of the formula (IV) -RCY2 C~ R -P~ 5 ( I~) R~2 CX~; n .

53~L
g wherein n is 1 or 2, R has the ~eaning given for rormula (I) Rl has ~he meaning given in a), and R5 if n is 1,represents C2-C8 alXylene or hydroxyalkylene or C4~C22acyloxyalkylene, and ir n is 2, repres nts the group (-CH2)2C~C~2-)2.
R as C2-C8 alkylene or hydroxyalkylene is ror example ethylene, l-me~hyle~hylene, propylene, 2-ethyl-propylene, 2~ethyl-2-hydroxymethylpropylene.
R5 as C4~C22 acyloxyalXylene is for example2-ethyl-2-acetoxymethylpropylene.
The following compounds are examples or polyalkyl-pipe~idine light stabilisers of this class:
3`3 8-aza-2,7,7,8,9,9-hexamethyl-1,4-dioxyspiro-~4.5]decane 34 9-aza-3-hydroxymethyl-3-ethyl-8,8,9,10,10-pen-tamethyl-1,5-dioxaspiro~5.5]undecane 9-aza-3-ethyl-3-asQtoY~.er~hy~-9-ac~t~
10,10-tetramethyl-1,5-dioxaspiro[;.5]undecane d~ Lig~t stabilisers of the formula (V) 1 (V), ~T --E."

R~I2 CH3 0 _ n wherein n is 1 or 2, R has the meaning given for formula (Ij, Rl has the meaning given in a), R6 represents hydrogen, Cl-C12 alkyl, allyl, benzyl, glycidyl, C2-C6 alkoxyalkyl, and R7 if n is 1, represents hydrogen, Cl-C12 alkyl, glycidyl, . :

53~

C3-C5 alkenyl, C7-Cg aralkyl, C5-C7 cycloalkyl, C2-C4 hydro-xyalkyl, C2-C6 alkoxyalkyl, C6-C10 aryl, and if n is 2, rePreSentS C2-C12 alkylene~ C6-C12 arylene or a group -CH2CH(OZ)CH2-(0CH2-CH(OZ~)CH2)2-, wherein Z'represents hydrogen, Cl-C18 alkyl, allyl, benzyl, C2-C12 alkanoyl or benzoyl.
Cl-C12 alXyl is for e~ample methyl, ethyl~n~PrPY
n-butyl, sec-butyl, tert-butyl, n-hexyl, n-octyl, 2-ethyl--I he.Yyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl.
Z as Cl-C18 alXyl can be for example ~he groups cited abo~e and, in addition, for e~a~ple n-t~idecyl,n-tetra-decyl, n-he~adecyl or n-octadecyl.
Substituents represented by C2-C6 alXoxyal.l~yl are for example methoxymethyl, ethoxymethyl, propo~ymethyl, tert-buto~ymethyl, ethoxyethyl, ethoxypropyl,n-butoxyethyl, tert-butoxvethyl, isopro~oxyethyl or ?ro?oxy~rcpvl.
R7 as C3-C_ alXenyl is for example l-propenyl, allyl, methallyl, 2-butenvl or 2-penteny'.
R7 as C7-Cg aralkyl is in particul2r phenethyl o_, most ?referably, benzyl, and, as C~-C7 cycloal.cyl is in . _ . , . . .. _ .
particular cyclohexyl.
t R7 as C2-C4hydroxyal-~yl is .or example 2-hvdro~y-e~hyl, 3-hydro~ypropyl or 4-hydroxybutyl.
R7 as C6-ClOaryl is in particula- phenyl, ~- or ~-naphthyl, which are unsubstitutsd or substituted by halo-gen or Cl-C~alkyl.
R7 as C2-C12alkylene is for example ethy~ene, pro-pylene, 2,2-dimethylpropylene, tetramethylene, he~amethyle-ne, octame~ylene, decamethylene or dodec~ethylene.
R7 25 C6-C12arvlene is or e~a.~ple o-m - or p-phen-ylene, l,~-naphthylene or 4,4'-diphenylene.
Z'as C2-Cl2al.k2noyl is for e~ampl~ propionvl, butv-rvl, oct~noyl, dodecanoyl or preferably acetyl.

;~
,,~ `

~953~L

The following compounds are examples of polyalkyl-piperidine light stabilisers of this class:
36 3-benzyl-1,3,8-triaza-7,7,8,9,9-pentamethyl-spiro[4.5]decane-2,4-diore 37 3-n-octyl-1,3,8-triaza-7,7,8,9,9-pentamethyl-spiro~4.5]decane-2,4-dione ~8 3-allyl-1,3,8-triaza-1,7,7,8,9,9-hexamethyl-spiro[4.5]decane~2,4-dione or the compounds of the following formulae:

'`.' ' ' ' ~, : :
.

.

5~

>_ , :~ I .
C) ~ ~ ~

~ <O ~ ~=O

~Xl ~ Z~ e~ " = O

o,~k ~ o ,,, . _,, _ . _ _ _ _ . . .. .. _ . . ..
. : ,, :
.: , : , :. :.: `
. : , : . ' , ~' ' ~.'''. ' '; ` , ~,' . . , .

5~

e) Light stabilisers of the formula (VI) ~r~ (VI) , Rlo wherein n is i or 2, R8 represents a group of the formula R ~h ~ ~H2R
- Y--(A)m ~ `~ Rl /\
C~3 CH2R

wherein R has the meaning given for formula ~ I ), Rl has the meaning given in a), Y is -O- or -NRll, A represents C2-C6 alkylene and m is O or 1, R9 represents the groups R8, ll 12 13~ N~cH2oRl3 or -~(C~20Rl3)2~ R if n is 1 represents the groups R8 or R9 and, if n is 2, represents the group -Y-Q-Y-, wherein Q represents C2-C6alkylene which is optionally interrupted by -~(R14)-, R11 represents Cl-Cl2alkyl, cyclohexyL, benzyl or Cl-C4hydroxyalkyl or a group of the formula R CH3 >~CH2R
--R
Cx3/ CH2R
Rl~ represents Cl-Cl2aLXyl, cyclohexyl, benzyl, C,-C~hyd-roxyalkyl, R13 represents hydrogen, Cl-Cl2alkyl or phenyl, and R14 represents hydrogen or ~he group -C'~20R13, or Rll and R12 together are C4-C5alXylene or oxaalkylene, or each ``. ' ` ' ' :, , ..
.
, ' '; :

3~L

of Rll and R12 represents a group of the formula ~ ~ 3 ~

CR3 CH~ y ~ 3-~
CH, ~ C~3 C~3 ~ CH3 Substituents represented by Cl-C12alkyl are for example methyl, ethyl, n-propyl, n-butyl, sec-butyl, tert-butyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n~decyl, n-undecyl or n-dodecyl.
Substituents represented by Cl-C4hydroxyalXyl are for example ethylene, propylene, 2,2~dimethylpropylene, tetramethylene or hexamethylene.
Rll and R12 together as C4-C5alkylene or oxaalkylene are for example tetramethylene, pentamethylene or 3 oxa-pen-tamethylene.
Compounds of the following formulae are examples of polyalkylpiperidine light stabilisers of this class:
~H3 42) ~ N ~ CH3 N~--~N
N

`~ ~

`

4~

4 9 ) 2 CH 3 J\ C~I CH
4 3 ) 3~ N~ ~ 3 2 5 ~,~ ~C2H5 CH3 CH3 C2H5 2 5 CH~ 3 ~C~3 CH2~X2--, N--CH3 3 ~H_ 4'1' ~ ~2 C7~2~\ /Lc - c~2 - c}~2~ ~--C~3 3 3 CH3 CtI3 f) Light stabilisers of the formula (VII) ~C~2R 1 L ~ R20 (VII) C~ CII2R n wherein n is 1 or 2, R represents hydrogen or methyl, and R20 i~ n is 1, represents C4-C18alkyl, C7-C12aralkyl, the group -CO-R15, Cl-C4alkyl substituted by -CN, -COOR16, -OH, -OCOR17 or -CH2-CH(OH) ~ , wherein R15 represents Cl-C12-alkyl, C2-C4alkenyl or phenyl, R16 represents Cl-C18alkyl, R17 represents C1-C18alkyl, C2-ClOalker.yl, cyclohe~yl, benzyl or C6-ClOaryl or R14, if n is 2, represents C4-C12-alkylene, 2-butenylene-1,4, xylylene, the groups 3~

2 2 18 Coo (CH2)2-, -CH2-ooC-R -Coo CH
-CH2-CH(OH)-cH2-o-Rl8-o-cH2-c~(oH)-cH2-~ wherein R
represents C2-ClOalkylene, phenylene, cyclohexylene or 2,2-diphenylenepropane, and Rlg represents C2-ClOalkylene, xylylene or cyclohexylene.
Substituents represented by C1-Cl2alkyl are for example methyl, ethyl, n-propyl, n-butyl, sec-butyl, tert.-butyl, n-hexyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, n-undecyl or n-dodecyl.
Substituents represented by Cl-Cl8alkyl can be for example the groups cited above and, in addition, for examp-le n-tridecyl, n-tetradecyl, n-hexadecyl or n-octadeyl.
Groups represented by C2-ClOalkylene are for examp-le ethylene, propylene, 2,2-dimethylpropylene, tetramethyl-ene, hexamethylene, octamethylene or decamethylene.
R1~ as C4-CI8alkyl is for example n-butyl,sec-butyl, tert-butyl, n-hexyl, n-octyl, 2-ethylhexyl, l,l-dimethyl-2-tert-butylethyl, n-nonyl t n-decyl, n-dodècyl, n-tridecyl, n-hexadecyl or n-octadecyl.
R14 as Cl-C4alXyl substituted by -CN is for example cyanomethyl, cyanoethyl, 3-cyano-n-propyl, 4-cyano-n-butyl.
Rl4 as C4-Cl2alkylene is for example 2,2-dimethyl-propylene, tetramethylene, hexamethylene, oct~methylene, decamethylene or dodecamethylene.
R14 as C7-Cl2aralkyl is in particular phenethyl, p-methylbenzyl, or most preferable, benzyl.
Rl5 as C2-C4alkenyl is for example vinyl, 1-propen-yl, allyl, methallyl, 2-butenyl.
R17 as C2-ClOalkenyl represents for example the groups cited in the deinition of Rl5 as alkenyl and, in addition, for example crotyl, 2-hexenyl, 2-octenyl or 2-de-cenyl.

; :. .

ii3~
~ 17 -R17 as C6-ClOaryl is for exam?le phenyl ~hich is unsuDstitutQd or substituted in the ortho- or par2-positisn bv met~yl, ethyl, isopropyl, n-butyl or tert-butyl.
The followi~g compounds are examples of polyal.kyl-?iperidine lignt st~bilisers of '~his class:
45 bis-[2-(2,2,6,6-tetramethylpiperidino)-eth~l]-sebacate 46 1-octoxycarbonylmethyl-2,2,6,6-tetramethyl-piperidine 47 1,~-bis-(2,2,6,6-tetramethylpiperidino)-2-butene.

g) Light stabilisers of~ the formula (VIII) RC~2~C~3 R
~ (VIII) Rl-N ~ ~E-CO~NH-C~2-~R2 ~CH /~CH

(22) or 0-, E is Cl-C3alkylene, the -CH2-CH(R )-O- group, wherein R23is hydrogen, methyl or phenyl, the -(CH2)3-NH- group or a simple bond, R is hydrogen 1 1 18 y , C3 C8alkenyl,C3 C8alkynyl, C7-C12aralkyl, Cl-C8alkanoyl, C3-C5alkenoyl, '``-- ~ R,21is hydrogen or C1-C18alkyl, R2~s hydrogen, C1-C18alkyl, C5-C7-cycloalkyl, C7-C12aralkyl, cyanoethyl, C6-ClOaryl, the -CH2-CH(R2~-OH group, wherein R~3is as defined above, a group of the formula RCH2y ~ R
Rl-N~_ 2 C}13 i3~

or a group of the formula -G-N~E-CO--NH-C~2-OR2 1 ~ ,R
C~3 ~ ~ C~3 wherein G can be c2-c6alkYlene or C6-C12arYlene' or R is a E-co-NH-cH2-oR2lgroup- 22 Cl-C18Alkyl is, for example, methyl, ethyl, n-propyl, n-butyl, sec-butyl, tert-butyl, n-hexyl, n-octyl, 2-ethyl-hexyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-hexadecyl, or n-octadecyl.
C7-C12Aralkyl is, for example, phenylethyl or, in particular, benzyl.
R1 as C3-C8alkenyl can be, for example, l-propenyl, allyl, methallyl, 2-butenyl, 2-pentenyl, 2-hexenyl, 2-octenyl or 4-tert-butyl-2-butenyl.
Rl as C3-C8alkynyl is preferably propargyl, and, as r Cl-C8-alkanoyl, is e.g. formyl, propionyl, butyryl, octanoyl, but preferably acetyl, and, as C3-C5alkenoyl, is in -particular acryloyl.
R22as C5-C7cycloalkyl is in particular cyclohexyl, and, as C6-ClOaryl, is in particular phenyl or ~- or ~-naph-thyl, which can be substituted by halogen or Cl-C4alkyl.
E as Cl-C3 alkylene is for example methylene, ethylene or propylene.
G as C2-C6alkylene is e.g. ethylene, propylene, 2,2-dimethylpropylene, tetramethylene or hexamethylene, and, as C6-Cl~arylene,is iso-, m- or p-phenylene, 1,4-naphthylene or 4,4'-diphenylene.

r ,~ ; ~ , :
". ~, ' ` . : ~ ' 5 3 ~

The following compounds are examples of polyalkyl-piperidine light stabilisers of this class:
48 N-hydroxymethyl-N'-1,2,2,6,6-pentamethylpiperidine-4-yl urea 49 N-methoxymethyl-N'-1,2,2,6,6-pentamethylpiperidine-4-yl urea N-methoxymethyl-N'-n-dodecyl-N'-1,2,2,6,6-penta-methylpiperidin-4-yl urea 51 0-(1,2,2,6,6-pentamethylpiperidin -4yl)-N-methoxymethyl urea.
h) Polymeric compounds, the recurring structural units of which contain a group of the formula I or which are linked through a bivalent group cor.responding to the formula I, wherein Rl represents a free valency, and otherwise R and Rl have the meanings given above, especially polyesters, polyethers, polyamides, poly-amines, polyurethanes, polyureas, polyaminotriazines, poly(meth) acrylates, poly(meth)acrylamides and the copolymers thereof which contain such radicals.
Examples of polyalkylpiperidine light stabilisers of this class are the compounds of the following formulae, wherein m is 2 to about 200:

11~
o =

o =l o=b ~

_. . ... . . .. .... . ... . . ., A. . .... ... . .. . .. .

.~

. ' ; .

` -ii3~

C \ =

m o=b t.~

~V V ~ V
~: m ~:
o=g ~
,~ ~ N
~ ,_ ~ ~ t<~ / ~ ~
= ~ ~2 ;~k~
~ V ^~ N V
j~_h~ L- t,~r 1~ -V ~ O = 1 ~--~; vd ~ J h~ ¦ ~N
~; ~ v~

I` o~

': ' : ' , ' ~ -`' - : : ' ;i3~

5g ~I C~2~
-~ ,~<CH3 0~7~N--CH3 rl ~C--CH ~
O~C ,~,<CH3

6 13 ~,N--CH3 CH /\

i) Compounds which contain in their molecule at least one 2-(2'-hydroxyphenyl)=benztriazole group or 2-hydroxybenz-ophenone group and at least one polyalkylpiperidine group.
Examples of polyalkylpiperidine light stabilisers of this class are the compounds of the following f~rmulae:

~0 G~
~ T ~ C ~ H3 C~2CH2CO ~ - CX3 OH

62 ~ C ~ CH2CO ~ N-C83 .

. , ' . ,~, '; : ' ~

~4~53~

It is also possible to use polyalkylpiperidine derivatives of classes a) to i) which form chemical bonds with the binder of the lacquer. This occurs wh~n the poly-alkylpiperidine derivative contains a reactive group suitable for the purpose, for example a glycidyl group or a methylol group.
Examples of such compounds are the polyalkylpiper-idine derivatives of class g) which contain methylol or methylol ether groups.
If the polyalkylpiperidine compounds are basic com-pounds, they can form salts with acids. Suitable acids for the saLt formation are for example inorganic acids or or-ganic carboxylic, sulfonic, phosphonic or phos~hinic acids, for e~ample hydrochloric acid, boric acid, phosphoric acid, acetic acid, salicyclic acid, toluenesulfonic acid or ben-zenephpsphonic acid.
The polyalkylpiperidine comp~unds can form complexes with complexforming metal compounds, for example with zinc (II) acetate, cobalt(II) acetylacetonate, nickel(II) acetyl-acetonate, aluminium(III) acetylacetonate, nickel(II)benzo-ate or aluminium(III) benzoylacetonate.
The acrylic resin lacquers, which can be stabilised against light,moisture and oxygen in accordance with the invention, are the conventional acrylic resin stoving lac-quers which are described, for example, in H. Kittells "Lehrbuch der Lacke und Beschichtungen", Vol. 1, Part 2, on pages 735 and 742 (Berlin 1972), and in "Lackkunstharze"
~1977), by H. Wagner and H.F. Sarx, on pages 229-238.
The polyester lacquers, which can be stabilised against the action of light and moisture, are ~he convention-al stoving lacquers described e.g. in H. Wagner and H.F.Sarx, op.cit., on pages 86-99.

The alkyd resin lacquers- which can be stabilised against the 2Cti on of light and moist~re in accor~ance ~i'~
~he invention, are ths conventional stoving lacquers which are used in partlcular for coating automoDiles (automobile fi~ishing lacquers), for example lacquers - based on alkyd melamine resins and alkyd/acrylic/melamine xeslns (see ~.
~agner a~d ~.F. Sarx, op. cit., pages 99-123).
The acid catalysed stoving lacquers- stabilised in accordance wi~h ~he invention are suitaDle ~oth Lor metal finish coat ngs and soiid shade finishes, es~ecially in the case of retouching finishes. The lacquers stabilisbd in accordance wit.~ the invention a~e preferably ap~lied in the conventional ma~ner by two methods, either by the single-coat me.nod cr by the two-coat _ method. In the latter method, the piçment-containing coat is applied firs' and then a covering coat of cle2r lacquer over it.
The æ~ount of polyalkylpiperidine ~erivative em-ployec. is 0. I to S ~ by weight, based on the solvent-f~ee binder, pre-erably 0.; to l ~ by weight. The lacquers can be dissolved or dispersed in customary organic solvents or in water or can be solvent-free.
When used in t-~o-coat finishes, ~he polyzl.cyl-~iperidine derivative eligible for use in the inventi~e st~bilising can be incorpcrzted either only in the unpig-mented finish nq lacquer or both in the unpi~mented finishing lacquer and in the pigmented priming lacquer. In the manufac-ture of acrylic modified alXyd resins or acrylic resins, pol,~e isable polyalXylpiperidine derivatives (ror e~a.~pie compounds 6 and 2S) can be pol~erised into ~he r-sin. The incor-oration into ~he lacque-r binde_ can also, however, e ef-_cted via oo ycondens2tion in tne manu~acture or, as the C2S2 mzy be, in the stoving, of t~.e ~elamlre, alXyd c- ?clyeater resins.

. :.
:'' , , 53~

Examples of polyalkylpiperidine derivatives whic~
can be incorporated by condensation are compounds 1, 30 and 31, and also 1-hydroxyethyl-4-hydroxy-2,~,6,6-tetra-methylpiperidine. The incorporation via polyaddition can be accomplished for example via the reaction of free glycidyl groups in the polyalkylpiperiZine derivative witll acid groups of the acrylic resin. These glycidyl groups can be incorporated by polymerising (meth~acrylic acid into the resin.
In these cases, the~e ls the additional advantage tha~ the light stabilises cannot be removed by ~xtraction or migration, so th-~t their action is very prolonged.
To attain maximum light stabili~y, the concurrent use of other conventional light stabilisers can be advan-tageous. Examples are W absorbers of the benzochenon~, benztriazole , acrylic acid derivative,or oxalanilide type, or metal-containing light stabilisers, for example organic nickel compounds.
If such combinations are employed, the sum of all light st~bilisers is 0~2 to 5~ by weight, preferably 0.
to 2~ by weight, based on the film-forming resin.
Further ingredients which the lacquers can con~ain are antioxidants, for example those of the sterically hindered phenol derivative type, phosphorus compounds, such as phosphites, phosphines or phosphonites, plasticisers, levelling assistants, hardening catalysts, thickeners, dis-persants or adhesion promoters.
The following Examples describe the inventive use of N-substituted polyalkylpiperidine 2erivatives in acid catalysed stoving lacguers b~sed on ao-ylic resin containing binder systems. Parts and ~ercentages are by weight.

~ _ .... . . . .. . . . ... . .. . .... . .. .... .. . .. . ... .. .. .. ... . . . . .. . ......

5~

Exam~le 1 tabilisin action of different polYalkYl~i~eridine deri-g vatives in a hot crosslinXable acrvlic resin lac~uer ca-. .
talvsed wi.;~ maleic acid (t~o-coat metallic effect finish) Basic com~osition of the lacquers I

a) Metallic ef'ect priminq lac~uer 27 par~s of polyester resin L 1850*(Dynamit Noçel AG) 3 parts of melamine resin Maprenal RT*(~arbwer~e Hoechst AG) 2 parts o- cellulose acetobutyrate CAB 531*(rastman Chem.-Cor?. ) 8 parts o' aluminium bronze ALCOA 726*(aluminium Corp.
o~ ~erica) 10 parts o,~ toluene

7 ?arts of xylene 3 p2rts of butanol 25 parts of butyl acetate 15 par.s of aromatic solvent Solvesso 150*(Esso ~G).

b) Un~iq~e~ted finishinq laçquer 56 par~s o~ acrylic resin Paraloid OL 42*(~ohm & ~a2s Cor?. ) 20 parts of melamine resin Cymel 301*(American Cv-ni.~ide Cor?. ) 3.5 ?arts of mal2ic acid (20% in dioxan) 2 ?a-_s of cellulose acetobut;~rate C.~B 551* (~as .m2n C~e.~. C~r`?-) 11 ?2r~s o butanol ~-5 ?2--s o butyl acetate.

* Trade Mark 4~

Pieces of aluminium sheeting measuring 57x7g mm x O.5 mm, which were coated with a primer based on poly-ester/epoxide resin, were first coated with the priming lacquer and subsequently with the finishing lacquer. The priming lacquer was sprayed on to a thickness of about 15 and aired for about 10 minutes. Then the clear lacquer was sprayed on to a thickness of about 30 ~. After being aired for 15 minutes the samples were stoved for 30 minutes at 150C.
Before application, 1~ (based on the film-forming resin) of the polyalkylpiperidine compound listed in column 1 of Table 1 was added to the priming lacquer in each case (numbered according to the Examples referred to the des-cription). For comparison, the following N unsubstituted poiyalXylpiperidine compounds designated by Roman numerals were also employed:
Compound I: 4-hydro~y-2,2,6,6-tetramethylpiperidine (N-unsubstituted homologue of compcunds 1, 2, 3 and 4).
Compound II: di-(2,2,6,6-tetramethylpiperidine-4-yl)-se-bacate.
Compound }II:
C~3 ~H3 r 1 3 \ CU3 CH3 (cH2)6 h ~ m 3 ~ 3 3 ~ 3 5~

After s~orage for 4 weeks in an air-conditioned room (23C~50~ relative ~midity), t~e coated sheets were subjected to weathering for 900 hours according to test method AST~ G-53~77 in a QUV tester. In t.his test, the ... .. . _ samples were subjected to weathering for 4 hou~s in a humid atmosphere and W light at 50~C and 'or 4 hours under W
light at 60C. Subsequently the weight loss of thefinishe~
was determined gravimetrically (indicated in g/m2 in column 2 or Table l), and ~he gloss of the surface of the finish was measured in accordance wi.h AST~ D 523 (the values are reported in column 3).
Table l . . _ .. _ .
Stabiliser Weight 1QSS . 20 gloss (aver2ged~
._., . ..
w_thout addi.ive 21.8 5 . . . _. __ ~ ~ , compound I 6.5 14 compound II 16,4 4 compound III 19.9 . .
compound l 6.5 66 compound ~ 6.9 67 compound 3 6.8 72 compound 4 6.8 4~
compound 16 5.7 55 compound 27 5.0 36 ..
com~ound 50 8.5 37 _ ,. , . .

.. , .. ,.. .. ~ .

'' ~' , ...
'- ' ' ~ 4~3~

Ex~m~le 2 ?reci?i~a~ions in an acid-czt21vs2d, ~.ot crosslirXa~7e ac-vlic resir. laccuer Each or t~e liSht s~zbilisers listed in col~n 1 o Ta~ie 2 (1~ based cn the coating) was dissolved in the priming-lacquer aescr~bed in Exzmple 1, initiallv without a~dition of catalyst. Then maleic acid was added as catalyst in the same amount as indicated in Example 1, and precipitation ef-ects were observed, dependin~ on the type of sta~iliser employed. The results are reported in Tzble 2.

Table 2 ~ . . , _ _ ... . ,., . _ .. . .. . . ._ Appearance o' the lacquer Stabiliser ~ith~acdition o,~~aci~ Wlth~addition of æi~
_ 11 wi~hout addition clear ¦ clear . , . _ compound I clear precipitate compound II clear precipitzte ccmpcun_ III clezr ¦ preci~it~te , - .
compound 1 clear clear ~-ompcund 2 clear clear compound 3 clear clear com?ound 4 clear clear compcund 1 clear clear compounc 16 cl~ar clear com?ound 27 clea- clear c_lm?o~r.c 41 cle2r ¦ clear ~ompcund ~o cle2r ¦ cle2r .. _ ~1 ` P~

, .
:

.

3g Example 3 Delays in curing by addition of light stabilisers to acid-catalysed hot crossli kable acrylic resin lacquers To the priming lac~uer described in Example l was added 0.34%
of maleic acid (MA) and 0.071% of p-toluenesulfonic acid (pTS) as catalysts (percentage amounts, based in each case on the film-forming resin). After addition of 1% of the stabi-lisers listed in column 1 of Table 3, the lacquers were applied wet to glass plates in layers of about 50 ~. The lacquers were then sto~ed for 30 minutes at 150C and, af-ter storage for l day in an air-conditioned room (23C/
50~ relative humidity), the hardness was evaluated by means of the oscillation test using the pendulum apparatus accord-ing to Ronig (DI~ 53 157). The results are reported in Tab-le 3.
Table 3 .

_ ~ . .
Stabiliser 0.34 % ~ 0.071 % oTS
_ . . .. _ ~
without addition 14~ 164 . ._ . .. __ __ _ .
compound II 76 adheres compound III 113 adheres ~ . ~ ___ compound 2 142 16~
compound 3 140 162 compound 4 145 15~
cQmpound l; 138 83 compound 15 152 57 compound 41 131 142 compound 50 145 162 :', .
.. .
~ . . ' ' '` "' ' ~ ' `

5~

Example 4 Influence of eolvalkylpiper1dine derivatives on spraying in an acid-catal~sed stovina laccuer (sin~le-coat ~etallic effect finish) Basic composition of the lacquer 57.6 parts of acrylic resin lacquer Synthracryl SC 300*(Farb-werke Hoechst), 50% in xylene/butanol 2:1 24.5 parts of melamine resin Maprenal MF 650*(Farbwerke Hoechst), 55% in isobutanol 1.3 parts of aluminium paste Stapa Mobil R*(Eckast-Werke, Furth, Germany) 3~ parts of maleic acid (20% in dioxane) 3.9 parts butyl glycol acetate 2 parts of ethyl glycol acetate 7.3 parts of xylene.
The metallic effect lacquer was adjusted with xylene to a spray viscosity of about 19 sec (DIN 53211) and sprayed onto aluminium sheets coated with a coil coat. After brief airing, the finishes were stoved for 30 minutes at 80C and evaluated. The results are reported in Table 4 (compounds I, II and III: cf. Example 1. The light stabilisers of the invention are numbered according to the Examples referred to in the description).

* Trade Mark 9f~

Table 4 f Light stabiliser* Appearance of the finishes (1~, based on lacquer solids) after stoving .. _ without additive faultless compound I pitting, spreading faults compound II dull, pitting compound III dull, pitting .__ __ . .
compound 1 faultless compound 2 faultless compound 3 faultless compound 19 faultless . .. . ._ . _ *dissolved in xylene and then added to the lacquer

Claims (18)

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A composition stabilized against the action of light, moisture and oxy-gen, consisting of an acid catalysed stoving lacquers based on hot crosslinkable acrylic, polyester or alkyd resins and stabilized with N-substituted 2,2,6.6-tetraalkylpiperidine compounds, their acid addition salts or complexes with metal compounds, optionally together with further stabilizers.

2. A composition according to claim 1 wherein the stabilizing compound is a group of the formula (I) (I) or a polymer, the recurring structural units of which contain a group of the for-mula I or are linked through a bivalent group corresponding to the formula I, wherein R1 represents a free valency, and otherwise R represents hydrogen or methyl and R1 represents C1-C18 alkyl, C1-C6 hydroxyalkyl, C3-C8 alkenyl, C3-C8 alkinyl, C7-C12 aralkyl which is unsubstituted or substituted in the alkyl moiety by hydroxyl, or C1-C8 alkanoyl or C3-C5 alkenoyl.

3. A composition according to ciaim 2 wherein the stabilizing compound is of the formula (II) (II), wherein n is 1 to 4, R is hydrogen or methyl, R1 represents C1-C18 alkyl, C1-C6hydroxyalkyl, C3-C8 alkenyl, C3-C8 alkynyl, C7-C12 aralkyl which is unsubstituted or substituted in the alkyl moiety by hydroxyl, or represents C1-C8 alkanoyl or C3-C5 alkenoyl, R2 if n is 1, represents hydrogen, C1-C12 alkyl, cyanoethyl, benzyl, a monovalent radical of a saturated or unsaturated aliphatic, cycloaliphatic or aromatic carboxylic acid, carbamic acid or phosphorus-containing acid or a monovalent silyl radical, and if n is 2, represents C1-C12 alkylene, C4-C12 alkenylene, xylylene, a divalent radical of a saturated or unsaturated aliphatic, cycloaliphatic, araliphatic or aromatic dicarboxylic acid, dicarbamic acid or phosphorus-containing acid or a divalent silyl radical, and, if n is 3, represents a trivalent radical of an aliphatic, cycloaliphatic or aromatic tricarboxylic acid, of an aromatic tricarbamic acid or of a phosphorus-containing acid or a trivalent silyl radical, and, if n is 4, represents a quadrivalent radical of an aliphatic, cycloaliphatic or aromatic tetracarboxylic acid.

4. A composition according to claim 3 wherein the stabilizing compound is of the formula (II), wherein n is 1 or 2, R is hydrogen or methyl, R1 is C1-C12 alkyl, allyl, benzyl, acetyl, acryloyl, and R2 if n is 1, represents a radical of an aliphatic carboxylic acid of 2 to 18 carbon atoms, of a cycloaliphatic carboxylic acid of 5 to 12 carbon atoms or of an aromatic carboxylic acid of 7 to 15 carbon atoms, and if n is 2, represents a radical of an aliphatic dicarboxylic acid of 2 to 12 carbon atoms, of a cycloaliphatic or aromatic dicarboxylic acid of 8 to 14 carbon atoms, of an aliphatic, cycloaliphatic or aromatic dicarbamic acid of 8 to 14 carhon atoms.

5. A composition according to claim 2 wherein the stabilizing compound is of the formula (III) (III) wherein n is 1 or 2, R is hydrogen or methyl, R1 represents C1-C18 alkyl, C1-C6 hydroxyalkyl, C3-C8 alkenyl, C3-C8 alkenyl C7-C12 aralkyl which is unsubstituted or substituted in the alkyl moiety by hydroxyl, or represents C1-C8 alkanoyl, C3-C5 alkenoyl, glycidyl, a -CH2CH(OH)-Z group, wherein Z is hydrogen, methyl or phenyl, R3 represents C1-C12 alkyl, C5-C7 cycloalkyl, C7-C8-aralkyl, C2-C18 alkanoyl, C3-C5 alkenoyl, or benzoyl, and R4 if n is 1, represents C1-C12 alkyl, C5-C7 cycloalkyl, C2-C8 alkenyl which is unsubstituted or substituted by a cyano, carbonyl or carbamide group, glycidyl, a group of the formula -CH2CH(OH)-Z
or of the formula -CONH-Z, wherein Z is hydrogen, methyl or phenyl, and, if n is 2, represents C2-C12 alkylene, C6-C12 arylene, xylylene, a -CH2-CH(OH)-CH2 group or a -CH2-CH(OH)-CH2-O-X-O-CH2-CH(OH)-CH2- group, wherein X represents C2-C10 alkylene, C6-C15 arylene, C6-C12 cycloalkylene, or, with the proviso that R3 does not represent alkanoyl, alkenoyl or benzoyl, R4 can also re-present a divalent radical or an aliphatic, cycloaliphatic or aromatic dicarboxylic acid or dicarbamic acid, or R3 and R4 together, if n is 1, can be the cyclic radical of an aliphatic or aromatic 1,2- or 1,3-dicarboxylic acid.

6. A composition according to claim 2 wherein the stabilizing compound is of the formula (IV) (IV) wherein n is 1 or 2, R is hydrogen or methyl, R1 represents C1-C18 alkyl, C1-C6 hydroxyalkyl, C3-C8 alkenyl, C3-C8 alkynyl, C7-C12 aralkyl which is unsubstituted or substituted in the alkyl moiety by hydroxyl, or represents C1-C8 alkanoyl, C3-C5 alkenoyl, glycidyl, a -CH2CH(OH)-Z group, wherein Z is hydrogen, methyl or phenyl, R5 if n is 1, represents C2-C8 alkylene or hydroxyalkylene or C4-C22 acyloxyalkylene, and if n is 2, represents the group (-CH2)2C(CH2-)2.

7. A composition according to claim 2 wherein the stabilizing compound is of the formula (V) (V) wherein n is 1 or 2, R is hydrogen or methyl, R1 represents C1-C18 alkyl,-C1-C6 hydroxyalkyl, C3-C8 alkenyl, C3-C8 alkynyl, C7-C12 aralkyl which is unsubstituted or substituted in the alkyl moiety by hydroxyl, or represents C1-C8 alkanoyl, C3-C5 alkenoyl, R6 represents hydrogen, C1-C12 alkyl, allyl, benzyl, C2-C6 alkoxyalkyl, and R7 if n is 1, represents hydrogen, C1-C12 alkyl, C3-C5 alkenyl, C7-C9 aralkyl, C5-C7 cycloalkyl, C2-C4-hydroxyalkyl, C2-C6 alkoxyalkyl, C6-C10 aryl, and, if n is 2, represents C2-C12 alkylene, C6-C12 arylene or a group -CH2CH(OZ')CH2-(OCH2-CH(OZ')CH2)2-, wherein Z' represents hydrogen C1-C18 alkyl, allyl, benzyl, C2-C12 alkanoyl or benzoyl.

8. A composition according to claim 2 wherein the stabilizing compound is the formula (VI) (VI) wherein n is 1 or 2 and R8 represents a group of the formual wherein R is hydrogen or methyl, R1 represents C1-C18 alkyl, C1-C6 hydroxyalkyl, C3-C8 alkenyl, C3-C8alkynyl, C7-C12 aralkyl which is unsubstituted or substituted in the alkyl moiety by hydroxyl, or represents C1-C8 alkanoyl, C3-C5 alkenoyl, glycidyl, a -CH2CH(OH)-Z group, wherein Z is hydrogen, methyl, or phenyl, Y
represents -0- or NR11, A represents C2-C6 alkylene, m is O or 1, R9 represents the groups R8, NR11R12, -OR12, -NHCH2OR13 or -N(CH2OR13)2, R10 if n is 1, represents the groups R8 or R9 and, if n is 2, represents the group -Y-Q-Y-, wherein Q represents C2-C6-alkylene which is optionally interrupted by -N(R14)-, R11 represents C1-C12 alkyl, cyclohexyl, benzyl or C1-C4 hydroxyalkyl or a group of the formula R12 represents C1-C12 alkyl, cyclohexyl, benzyl, C1-C4 hydroxyalkyl, R13 represents hydrogen, C1-C12 alkyl or phenyl, and R14 represents hydrogen or the group -CH2OR13, or R11 and R12 together are C4-C5 alkylene or oxaalkylene, or each of R11 and R12 also represents a group of the formula

9. A composition according to claim 1 wherein the stabilizing compound is of the formula (VII) (VII) wherein n is 1 or 2, R represents hydrogen or methyl, and R20 if n is 1, represents C4-C18 alkyl, C7-C12 aralkyl, the group -CO-R15, C1-C4 alkyl substituted by -CN, -COOR16, -OH, -OCOR17, or -CH2-CH(OH) and R15 represents C1-C12 alkyl, C2-C4 alkenyl or phenyl, R16 C1-C18 alkyl, R17 represents C1-C18 alkyl, C2-C10 alkenyl, cyclohexyl, benzyl or C6-C10 aryl, or R14, if n is 2, represents C4-C12 alkylene, 2-butenylene-1,4, xylylene, the groups -(CH2)2-OOC-R18-COO-(CH2)2, -CH2-OOC-R19-COO-CH2- or -CH2-CH(OH)-CH2-0-R18-O-CH2-CH(OH)-CH2-, wherein R18 represents C2-C10 alkylene, phenylene, cyclohexylene or 2,2-diphenylenepropane, and R19 represents C2-Cl0 alkylene, xylylene or cyclohexylene.

10. A composition according to claim 2 wherein the stabilizing compound is of the formula (VIII) (VIII) wherein D is -N(R22)- or -O-, E is C1-C3 alkylene, the -CH2-CH(R23)-0- group, wherein R23 is hydrogen, methyl or phenyl, the -(CH2)3-NH- group or a simple bond, R is hydrogen or methyl, R1 is C1-C18 alkyl, C3-C8 alkenyl, C3-C8 alkynyl, C7-C12 aralkyl, C1-C8 alkanoyl, C3-C5 alkenoyl, R21 is hydrogen or C1-C18 alkyl, R22 is hydrogen, C1-C18 alkyl, C5-C7 cycloalkyl, C7-C12 aralkyl, cyanoethyl, C6-C10 aryl, the -CH2-CH(R23)-OH group, wherein R23 is as defined above, a group of the formula or a group of the formula wherein G can be C2-C6 alkylene or C6-C12 arylene, or R22 is a E-CO-NH-CH2-OR21group.

11. A composition according to claim 2, wherein polymeric compounds are used as stabilizers, the recurring structural units of which contain a group of the formula I or are linked through a bivalent group corresponding to the formula I, wherein R1 represents a free valency, and otherwise R and R1 have the meanings given in claim 2, in particular polyesters, polyethers, polyamides, polyamines, polyurethanes, polyureas, polyaminotriazines, poly(meth)acrylates, poly(meth)acrylamides and the copolymers thereof, which contain such radicals.

12. A composition according to claim 2, wherein compounds are used as stabilizers which contain in their molecule at least one 2-(2'-hydroxyphenyl)-benztriazole or 2-hydroxybenzophenone group and at least one polyalkylpiperidine group.

13. A composition according to claim 2, wherein an acid addition salt of a N-substituted 2,2,6,6-tetraalkylpiperidine compound is used as a stabilizer.

14. A composition according to claim 2, wherein a complex of a N-substituted 2,2,6,6-tetraalkylpiperidine compound with a metal compound is used as a stabilizer.

15. A composition according to claim 2, wherein the N-sub-stituted 2,2,6,6-tetraalkylpiperidine compound is used as a stabilizer in an amount of 0.1 to 5% by weight, based on the solvent-free binder (film-forming resin).

16. A composition according to claim 2, wherein additionally other light stabilizers are used, the amount of which is chosen such that the sum of all light stabilizers is 0.2 to 5% by weight, based on the solvent-free binder (film-forming resin).

17. A composition according to claim 2, wherein antioxidants, plasticisers, levelling agents, hardening catalysts, thickeners, dispersants or adhesion promoters are added.

18. A composition according to claim 1, wherein acid-catalysed stoving lacquers based on hot crosslinkable acrylic or alkyd resins are stabilized.