DE4003129A1 - Styrene]-butadiene] copolymer synthetic resin film - contains hindered bisphenol mono:acrylate, benzophenone or benz:triazole UV absorber and/or hindered amine light stabiliser - Google Patents

Abstract

Styrene-based synthetic resin film (I) contains a styrene-butadiene (SB) block copolymer with S:B ratio (60:40)-(95:5) (II) in combination with (A) 2,2'-ethylidene-bis (4,6-di-tert.-amylphenol) monoacrylate (III) and (B) UV absorber(s) of the benzophenone or benztriazole type (IV) and/or sterically-hindered amine light stabiliser(s) (V). (I) is produced by mixing (II) with (A) and (B) and extruding the mixt. Amt. of (A) is 0.1-1 pt. wt. w.r.t. 100 pts. wt. (II); component (B) comprises both (IV) and (V); (IV) is 2-(3-tert.-butyl-2-hydroxy -5-methyphenyl)-5-chlorobenztriazole; (V) is e.g. bis-(2,2,26,6-morpholino-1,3,5-triazine-2,4-diyl) -((2,2,6,6-tetramethyl-4-piper-idyl)imino)-hexamethylene-((2,2,616 -tetramethyl-4-piperidyl)-imino)) (Vb); amt of (B) is 0.01-1 pt.wt., w.r.t. 100 pts. wt. (II) ; (I) also contains a lubricant, pref. erucamide. USE/ADVANTAGE - (I) is useful esp. as heat-shrink film for can and bottle labelling, seals for closures and (when biaxially oriented) shrink-film food packaging. The extruded film has excellent surface quality, and excellent resistance to weathering and to dis-coloration under the action of heat and moisture, and can be printed on.

Description

The present invention relates to a film made of styrene Butadiene block copolymer.

A styrene-butadiene block copolymer film can e.g. B. as Bottle label or seal can be used. The Block copolymer is often mixed with a UV absorber, such as a benzophenone derivative and a benzotriazole derivative. The However, UV absorber calls a fish-eye angel during film extrusion forth. This problem is therefore required to solve. To prevent the formation of fish-eye angels, the addition of 2-t-butyl-6- (3-t-butyl-5-methyl-2-hydroxybenzyl) - 4-methylphenyl acrylate suggested; see. JP-A- 60-129 241, 61-61 826 and 61-159 442.

However, after recently the film extrusion temperature is to be increased to increase production conventional technology is no longer sufficient Terms of problems caused by the occurrence of Fisheye angels are caused because the inadequate  Heat resistance of the film thereby deteriorating Properties, such as printability, result and because continue a film made using conventional technology was yellowed during storage in moist heat.

The invention has for its object a synthetic resin film to create on styrene, in which during extrusion no fish-eye angel occurs at high temperature printable, the improved resistance to discoloration shows in damp heat and the very good Has weather resistance. This task is accomplished by the Invention solved.

The invention thus relates to a styrene-based synthetic resin film, which is characterized in that it comprises a styrene-butadiene block copolymer with a weight ratio of styrene to butadiene of 60:40 to 95: 5 in combination with the following components:
A) 2,2'-ethylidene bis (4,6-di-t-amylphenol) monoacrylate
and
B) at least one UV absorber of the benzophenone type or benzotriazole type and / or a light stabilizer of the sterically hindered amine type.

The invention further relates to a method for producing a styrene-based synthetic resin film, in which a styrene-butadiene block copolymer with the weight ratio specified above also has
A) 2,2'-ethylidene bis (4,6-di-t-amylphenol) monoacrylate
and
B) at least one UV absorber of the benzophenone type or benzotriazole type and / or a light stabilizer of the sterically hindered amine type is mixed and the mixture is extruded.

In the present invention, the phenolic compound of component (A) preferably in an amount in the range from 0.1 to 1 part by weight based on 100 parts by weight used on styrene-butadiene block copolymer. A lot is less than 0.1 part by weight in the prevention effect insufficient of fish-eye angel, and a lot larger as 1 part by weight leads to bleeding.

UV absorbers include those from benzophenone derivatives and benzotriazole derivatives as component (B) in the present Invention effective. Examples of benzophenone type UV absorbers include the following connections:

2-hydroxy-4-methoxybenzophenone,
2-hydroxy-4-octoxybenzophenone,
2,2′-dihydroxy-4-methoxybenzophenone,
Bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, and
2,2 ', 4,4'-tetrahydroxybenzophenone.

Examples of benzotriazole type UV absorbers include the following Connections one:

2- (2-hydroxy-5-methylphenyl) benzotriazole,
2- [2-hydroxy-3- (3,4,5,6-tetrahydrophthalimide methyl) -5-methylphenyl] b-enzotriazole,
2- (3-t-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzotriazole,
2- (3,5-di-t-butyl-2-hydroxyphenyl) benzotriazole,
2- (2-hydroxy-5-t-octylphenyl) benzotriazole,
2- (3,5-di-t-amyl-2-hydroxyphenyl) benzotriazole,
2- [2-hydroxy-3,5-bis ( α, α -dimethylbenzyl) phenyl] -2H-benzotriazole,
2- (3,5-di-t-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole,
2,2′-methylene-bis- [6- (2-H-benzotriazol-2-yl) -4- (1,1,3,3-tetramethylbutyl) phenol],
a condensate of poly (3-11) (ethylene glycol) with
3- [3- (2H-benzotriazol-2-yl) -5-t-butyl-4-hydroxyphenyl] - methyl propionate,
3- [3-t-butyl-5- (5-chloro-2H-benzotriazol-2-yl) -4-hydroxy-phenyl] propionic acid 2-ethylhexyl ester,
3- [3-t-butyl-5- (5-chloro-2H-benzotriazol-2-yl) -4-hydroxy-phenyl] propyl octyl ester,
Methyl 3- [3-t-butyl-5- (5-chloro-2H-benzotriazol-2-yl) -4-hydroxyphenyl] propionate,
3- [3-t-butyl-5- (5-chloro-2H-benzotriazol-2-yl) -4-hydroxy-phenyl] propionic acid and
2,2'-methylene-bis- [4-t-butyl-6- (2H-benzotriazol-2-yl) phenol].

Among these UV absorbers is 2- (3-t-butyl-2-hydroxy-5-methylphenyl) - 5-chlorobenzotriazole preferred.

Examples of sterically hindered light stabilizers Amines include the following compounds:

Bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, a polycondensate of dimethyl succinate with 1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethylpiperidine, Poly [(6-morpholino-1,3,5-triazine-2,4-diyl) - {(2,2,6,6-tetramethyl- 4-piperidyl) imino} hexamethylene - {(2,2,6,6-tetramethyl- 4-piperidyl) imino}], Bis- (1,2,2,6,6-pentamethyl-4-piperidyl) -2- (3,5-di-t-butyl-4- hydroxybenzyl) -2-butylmalonate, 4- [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -1- [2- {3- (3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy} ethyl] - 2,2,6,6-tetramethylpiperidine, Bis- (1,2,2,6,6-pentamethyl-4-piperidyl) decanedioate, Tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, Poly - [{6- (1,1,3,3-tetramethylbutyl) imino-1,3,5-triazine-2,4- diyl} - {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene- {(2,2,6,6-tetramethyl-4-piperidyl) imino}], a mixed ester of 1,2,3,4-butanetetracarboxylic acid 1,2,2,6,6-pentamethyl-4-piperidinol and 1-tridecanol,  a mixed ester of 1,2,3,4-butanetetracarboxylic acid 2,2,6,6-tetramethyl-4-piperidinol and 1-tridecanol, a mixed ester of 1,2,3,4-butanetetracarboxylic acid 1,2,2,6,6-pentamethyl-4-piperidinol and 3,9-bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,10-tetra-oxa- spiro [5 · 5] undecan, a mixed ester of 1,2,3,4-butanetetracarboxylic acid 2,2,6,6-tetramethyl-4-piperidinol and 3,9-bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,10-tetra-oxaspiro [5 · 5] undecane, a polycondensate of N, N'-bis (2,2,6,6-tetramethyl-4-piperidyl) with hexamethylenediamine 1,2-dibromoethane, 2-methyl-2- (2,2,6,6-tetramethyl-4-piperidylamino) -N- (2,2,6,6-tetramethyl-4-piperidyl) propionamide, N, N ′, 4,7-tetrakis [4,6-bis {N-butyl-N- (2,2,6,6-tetramethyl-4- piperidyl) amino} -1,3,5-triazin-2-yl] -4,7-diazadecan-1.10- diamine, N, N′-tris [4,6-bis {N-butyl-N- (2,2,6,6-tetramethyl-4-piperidyl) amino} - 1,3,5-triazin-2-yl] -4,7-diazadecan-1,10-diamine, Bis- (1-acryloyl-2,2,6,6-tetramethyl-4-piperidyl) -2,2-bis- (3,5-di-t-butyl-4-hydroxybenzyl) malonate, N, N ′, 4,7-tetrakis [4,6-bis {N-butyl-N- (1,2,2,6,6-pentamethyl- 4-piperidyl) amino} -1,3,5-triazin-2-yl] -4,7-diazadecan-1,10- diamine, N, N ′, 4-tris- [4,6-bis {N-butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino} - 1,3,5-triazin-2-yl] -4,7-diazadecan-1,10-diamine, Bis (2,2,6,6-tetramethyl-4-piperidyl) succinate, 2,2,6,6-tetramethyl-4-piperidyl methacrylate, 1,2,2,6,6-pentamethyl-4-piperidyl methacrylate and Tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate.

Among these sterically hindered light absorbers Amines are preferred:

Bis- (2,2,6,6-tetramethyl-4-piperidyl) - sebacate and poly - [(6-morpholino-1,3,5-triazine-2,4-diyl) -  {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene- {(2,2,6,6-tetra-methyl-4-piperidyl) imino}].

The composition of the present invention contains at least a benzophenone type UV absorber, a benzotriazole type or a steric type light stabilizer hindered amines, as illustrated by the examples above. The use of both a UV absorber and one Sterically hindered amine type light stabilizer in Combination is preferred.

The amount of UV absorber and / or light stabilizer is preferably in the range from 0.01 to 1 part by weight, based on 100 parts by weight of styrene-butadiene block copolymer. An admixture of less than 0.01 part by weight is insufficient in In terms of improving weather resistance, and a lot of more than 1 part by weight calls phenomena like Bleeding out.

The styrene-butadiene block copolymer described in the present Invention used can itself be present and can, if necessary, also continue to use general-purpose polystyrene, impact-resistant polystyrene or similar materials be.

If necessary, the composition of the present invention with other additives, such as Phenol antioxidants, phosphorus-containing antioxidants, Lubricants, pigments and inorganic fillers be mixed. These additives are shown below exemplified.

The phenolic antioxidants include e.g. B. a:

3- (3,5-dt-butyl-4-hydroxyphenyl) propionic acid octadecyl ester,
Triethylene glycol bis- [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate],
3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5 · 5] undecan,
Pentaerythrityl tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate],
Tris (3,5-di-t-butyl-4-hydroxybenzyl) isocyanurate and
1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene.

The phosphorus-containing antioxidants include e.g. B. a:

Tris (2,4-di-t-butylphenyl) phosphite,
Bis- (2,4-di-t-butylphenyl) pentaerythritol diphosphite,
Bis- (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite,
Tetrakis (2,4-di-t-butylphenyl) -4,4′-biphenylenediphosphonite, and
Tris (nonylphenyl) phosphite.

The lubricants include e.g. B. acid amides, such as ethylene bis fatty acids (C₁₆ and C₁₈) amides, higher fatty acid (C₈- C₂₂) amides, stearyl erucamide and oleyl palmitamide. Under Erucamide has a particularly good effect on printability and solvent resistance. Therefore is the film when it is printed for its use should preferably produce from a mixture that the Lubricants (preferably erucamide) in combination with the Contains components (A) and (B) of the present invention. The amount of lubricant used is preferably 0.05 to 1 part by weight, based on 100 parts by weight of the styrene Butadiene block copolymer, preferably 0.05 to 0.5 part by weight.

The inorganic fillers include e.g. B. silicon dioxide, Calcium carbonate, magnesium carbonate, calcium sulfate, aluminum hydroxide, Talc and clay. The amount of filler is provided applied, usually not more than 1 part by weight, based on 100 parts by weight of the styrene-butadiene block copolymer and is preferably in the range of 0.05 to 0.5 Parts by weight.  

The styrene-based films of the present invention have excellent weather resistance properties, Resistance to discoloration in moist heat, Surface quality after extrusion and printability on.

The films of the present invention are therefore provided uniaxially oriented, especially as heat shrink films for Labels for cans and bottles and for sealing seals suitable. Biaxially oriented films can also used for shrink packaging of food will.

The examples illustrate the invention without restricting it.

Example 1

ASAFLEX 810 (styrene-butadiene block copolymer; Ashai Kasei Kogyo K.K.) is used to extract the present additives, such as Antioxidants, with a liquid mixture of n-hexane and Isopropanol in a volume ratio of 4: 1 added, then in Air flow of a hair dryer dried. The material obtained is used as a copolymer base. Furthermore, the following connections as phenolic antioxidants, UV absorbers and Light stabilizers used.

AO-1: 2,2'-ethylidene bis (4,6-di-t-amylphenol) monoacrylate
AO-2: 2-t-butyl-6- (3-t-butyl-5-methyl-2-hydroxybenzyl) -4-methylphenylacrylate
UV-1: 2- (3-t-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzotriazole
HALS-1: bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate
HALS-2: poly [(6-morpholino-1,3,5-triazine-2,4-diyl) - {(2,2,6,6-tetramethyl-4-piperidyl) imino} hexamethylene- {(2, 2,6,6-tetramethyl-4-piperidyl) imino}].

These compounds are listed in Table I. Amount mixed with the styrene-butadiene block copolymer. Farther Erucamide is used as a lubricant in every mixture an amount of 0.2 wt .-% added. The mixture is made by a 30 mm extruder at an extrusion temperature of 230 ° C extruded into a plate, which is then 5 times using a stenter at a temperature of 100 ° C a 50 µm thick film is stretched.

The plates or foils obtained are shown in the following Properties rated.

Extrusion texture

The surface condition of the plate after extrusion is assessed visually. A plate without fisheye angel will rated "good" and a plate in the fish-eye angel was found to be "not good". One plate, the fish-eye angel contains is after stretching to a film bad in their printing properties because of the proportion of Fish-eye angels cannot be coated with printing ink.

Weather resistance

The film is shrunk at both ends in a sunshine Wetter-o-Meter (WEL-3-HC type, manufactured by the Suga Test Instruments Co.) attached and in light one Exposed to temperature of 83 ° C. The time until the tensile strain in the width direction (the direction that is not attached is) 0% is measured.  

Discoloration in damp heat

The film is aged for one month at a temperature of 60 ° C. and a relative humidity of 90% in a climatic chamber from KK Nagano Kagaku Kiki Saisakusho. Then ten sheets of the film are cut into strips and the color difference Δ YI from the starting color is determined.

Printability

The film is printed with printing ink for polystyrene. A Cellophane adhesive tape is on the printed surface fixed and then removed the tape. If the color from Tape is not carried away at all, the evaluation given "good". The designation "good *" occurs when the tape Peeling test no peeling of the paint occurs in some However, the ink does not cover the original print covered.

The results are in Table I along with the proportions of test connections listed.  

Table I

Example 2

The procedure of Lot # 1 in Table I is repeated without erucamide. The film obtained is subjected to the same test as in Example 1. As a result, the extrusion quality is good, the weather resistance is 70 hours, and the discoloration in wet heat ( Δ YI) is 10. These are all values similar to batch # 1; however, the printability is not so good, and some of the printed ink is peeled off by the tape.

Claims (9)

1. Styrene-based synthetic resin film, characterized in that it comprises a styrene-butadiene copolymer with a weight ratio of styrene to butadiene from 60:40 to 95: 5 in combination with the following components:

• (A) 2,2'-ethylidene bis (4,6-di-t-amylphenol) monoacrylate and
• (B) at least one UV absorber of the benzophenone type or benzotriazole type and / or a light stabilizer of the sterically hindered amine type.

2. Film according to claim 1, in which the component (A) in the amount of 0.1 to 1 part by weight based on 100 parts by weight of the styrene-butadiene block copolymer is present. 3. Film according to one of claims 1 and 2, which at the same time the UV absorber and the light stabilizer from Type of sterically hindered amines as component (B) contains. 4. Film according to one of claims 1 to 3, in which the UV absorber of component (B) 2- (3-t-butyl-2-hydroxy-5-methylphenyl) - 5-chlorobenzotriazole. 5. Film according to one of claims 1 to 4, in which the Sterically hindered amine type light stabilizer Component (B) bis (2,2,6,6-tetra-methyl-4-piperidyl) sebacate or poly - [(6-morpholino-1,3,5-triazine-2,4-diyl) - {(2,2,6,6- tetramethyl-4-piperidyl) imino} hexamethylene - {(2,2,6,6-tetramethyl- 4-piperidyl) -imino}]. 6. Film according to one of claims 1 to 5, in which the Component (B) in an amount of 0.01 to 1 part by weight, based per 100 parts by weight of the styrene-butadiene block copolymer is present.   7. Film according to one of claims 1 to 6, which further contains a lubricant. 8. A film according to claim 7, in which the lubricant is erucamide is. 9. A process for producing a styrene-based synthetic resin film, characterized in that a styrene-butadiene block copolymer with a weight ratio of styrene to butadiene of 60:40 to 95: 5 with

• (A) 2,2'-ethylidene bis (4,6-di-t-amylphenol) monoacrylate and
• (B) at least one UV absorber of the benzophenone type or benzotriazole type and / or a light stabilizer of the sterically hindered amine type are mixed and the mixture is extruded.