Composition

1. A stabilising composition for hot melt adhesives, comprising:

(a) a first stabilising component comprising at least one phenolic antioxidant;

(b) a second stabilising component comprising at least one phosphite antioxidant;

(c) a third stabilising component comprising at least one antioxidant containing a sulphur group having the formula —CH 2 —(S) x —CH 2 —, wherein x=1 or 2, and wherein neither of the —CH 2 — groups is directly bonded to an aromatic group; and

(d) a fourth stabilising component comprising at least one acid scavenger.

2. A stabilising composition according to claim 1 , wherein x=1.

3. A stabilising composition according to claim 1 , wherein stabilising component (a) comprises one or more hindered phenolic antioxidants.

4. A stabilising composition according to claim 3 , wherein each hindered phenolic antioxidant comprises tetrakismethylene(3,5-di-t-butyl-4-hydroxyhydrocinnamate) methane; 2,2′-thiodiethylene bis[3(3,5-di-t-butyl-4-hydroxyphenyl)propionate]; C13-C15 linear and branched alkyl esters of 3-(3′5′-di-t-butyl-4′-hydroxyphenyl) propionic acid; octadecyl 3-(3′,5′-di-t-butyl-4′-hydroxyphenyl) propionate; 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate; 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene; N,N′-hexamethylene bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionamide]; 1,2-bis(3,5-di-t-butyl-4-hydroxyhydrocinnamoyl)hydrazine; C9-C11 linear and branches alkyl esters of 3-(3′,5′-di-t-butyl-4′-hydroxyphenyl)propionic acid; triethyleneglycol-bis-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate]; the butylated reaction product of p-cresol and dicyclopentadiene; 2,2′-methylenebis(6-t-butyl-4-methylphenol); 2,2′-ethylidenebis[4,6-di-t-butylphenol]; butylated hydroxytoluene; or compatible mixtures of two or more thereof.

5. A stabilising composition according to claim 4 , wherein the hindered phenolic antioxidant comprises tetrakismethylene(3,5-di-t-butyl-4-hydroxyhydrocinnamate) methane.

6. A stabilising composition according to claim 1 , wherein stabilising component (b) comprises one or more organophosphite antioxidants.

7. A stabilising composition according to claim 6 , wherein each organophosphite antioxidant comprises a non-hindered triaryl phosphite, a low hindered triaryl phosphite, an alkylaryl phosphite or a trialkyl phosphite.

8. A stabilising composition according to claim 6 , wherein each organophosphite antioxidant does not comprise a fully hindered triaryl phosphite.

9. A stabilising composition according to claim 6 , wherein each organophosphite antioxidant comprises bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite; 2,4,6-tri-tert-butylphenyl-2-butyl-2-ethyl-1,3-propanediol phosphite; tris(2,4-di-t-butylphenyl)phosphite; tetrakis (2,4-di-t-butylphenyl)4,4′-biphenylene diphosphonite; tris(4-n-nonylphenyl)phosphite; tris(mono-nonylphenyl)-phosphite; distearylpentaerythritol diphosphite; bis(2,4-dicumylphenyl) pentaerythritol diphosphite; Phoshorous acid, mixed 2,4-bis(1,1-dimethylpropyl)phenyl and 4-(1,1-dimethylpropyl)phenyl triesters; tris(dipropyleneglycol) phosphite, C 18 H 39 O 9 P; poly(dipropylene glycol) phenyl phosphite; diphenyl isodecyl phosphite, C 22 H 31 O 3 P; phenyl diisodecyl phosphite; heptakis (dipropyleneglycol) triphosphite; bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite; or compatible mixtures of two or more thereof.

10. A stabilising composition according to claim 9 , wherein the organophosphite antioxidant comprises bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite.

11. A stabilising composition according to claim 1 , wherein stabilising component (c) comprises one or more thioesters.

12. A stabilising composition according to claim 11 , wherein the or each thioester comprises dilauryl-3,3′-thiodipropionate; distearyl-3,3′-thiodipropionate; ditridecylthiodipropionate; 2,2′-thiodiethylene bis[3(3,5-di-t-butyl-4-hydroxyphenyl)propionate]; dimyristyl thiodipropionate; distearyl-disulfide; or compatible mixtures of two or more thereof.

13. A stabilising composition according to claim 11 , wherein the thioester comprises pentaerythritol tetrakis (β-laurylthiopropionate).

14. A stabilising composition according to claim 1 , wherein the acid scavenger is selected from epoxidised oils, metal salts of fatty acids, metal oxides, metal hydroxides, metal carbonates, metal salts and hydrotalcite compounds.

15. A stabilising composition according to claim 14 , wherein the acid scavenger comprises epoxidised soy bean oil.

16. A stabilising composition according to claim 14 , wherein the acid scavenger comprises calcium stearate.

17. A stabilising composition according to claim 14 , wherein the acid scavenger comprises a magnesium aluminium hydroxide carbonate hydrate.

18. A stabilising composition according to claim 14 , wherein the acid scavenger comprises calcium oxide, zinc oxide, calcium hydroxide, calcium carbonate, calcium lactate or zinc octanoate.

19. A stabilising composition according to claim 1 , wherein the stabilising composition is in solid form.

20. A stabilising composition according to claim 1 , wherein the stabilising composition is in liquid form.

21. A stabilised hot melt adhesive comprising a polymeric base material and a stabilising composition comprising:

(a) a first stabilising component comprising at least one phenolic antioxidant;

(b) a second stabilising component comprising at least one phosphite antioxidant;

(c) a third stabilising component comprising at least one antioxidant containing a sulphur group having the formula —CH 2 —(S) x —CH 2 —, wherein x=1 or 2, and wherein neither of the —CH 2 — groups is directly bonded to an aromatic group; and

(d) a fourth stabilising component comprising at least one acid scavenger.

22. A stabilised hot melt adhesive according to claim 21 , wherein x=1.

23. A stabilised hot melt adhesive according to claim 21 , wherein stabilising component (a) is present in an amount of from about 0.1% to about 1% by weight of stabilised hot melt adhesive.

24. A stabilised hot melt adhesive according to claim 23 , wherein stabilising component (a) is present in an amount of from about 0.2% to about 0.46 by weight of stabilised hot melt adhesive.

25. A stabilised hot melt adhesive according to claim 21 , wherein stabilising component (b) is present in an amount of from about 0.1% to about 1% by weight of stabilised hot melt adhesive.

26. A stabilised hot melt adhesive according to claim 25 , wherein stabilising component (b) is present in an amount of from about 0.4% to about 0.7% by weight of stabilised hot melt adhesive.

27. A stabilised hot melt adhesive according to claim 21 , wherein stabilising component (c) is present in an amount of from about 0.1% to about 1% by weight of stabilised hot melt adhesive.

28. A stabilised hot melt adhesive according to claim 27 , wherein stabilising component (c) is present in an amount of from about 0.4% to about 0.7% by weight of stabilised hot melt adhesive.

29. A stabilised hot melt adhesive according to claim 21 , wherein the acid scavenger is present in an amount of from about 100 to about 5000 ppm of the stabilised hot melt adhesive.

30. A stabilised hot melt adhesive according to claim 29 , wherein the acid scavenger is present in an amount of from about 900 to about 1100 ppm of the stabilised hot melt adhesive.

31. A stabilised hot melt adhesive according to claim 21 , wherein the polymeric base material comprises a polyolefin comprising a homopolymer of ethylene, propylene, butylene or a higher alkene; a random copolymer of ethylene, propylene or butylene; a block copolymer of ethylene, propylene or butylene; or mixtures thereof.

32. A stabilised hot melt adhesive according to claim 31 , wherein the polymeric base material comprises a polypropylene homopolymer or copolymer.

33. A stabilised hot melt adhesive according to claim 31 , wherein the stabilised hot melt adhesive is substantially free from anti-gel agents.

34. A stabilised hot melt adhesive according to claim 21 , for use in packaging and converting applications.