BIODEGRADABLE LAMINATING FILM AND CONTAINER MADE OUT OF IT

Abstract

A biodegradable laminating film having the layer structure A/B, wherein the 0.5 to 7 m thick layer A comprises a polyurethane or acrylate adhesive; and wherein the 5 to 150 m thick layer B comprises an aliphatic polyester and/or aliphatic-aromatic polyester, wherein the aliphatic-aromatic polyester is composed as follows: b1-i) 30 to 70 mol %, based on components b1-i and b1-ii, of a C6-C18 aliphatic dicarboxylic acid; b1-ii) 30 to 70 mol %, based on components b1-i and b1-ii, of an aromatic dicarboxylic acid; b1-iii) 98 to 100 mol %, based on components b1-i and b1-ii, of 1,3-propanediol or 1,4-butanediol; b1-iv) 0 to 2% by weight, based on components b1-i to b1-iii, of a chain extender and/or branching agent. The invention further relates to a food and/or beverage container comprising a substrate and a biodegradable laminating film coating, as the one described.

Claims

1. A biodegradable laminating film having the layer structure A/B, wherein the 0.5 to 7 m thick layer A comprises a polyurethane or acrylate adhesive; and wherein the 5 to 150 m thick layer B comprises an aliphatic polyester and/or aliphatic-aromatic polyester, wherein the aliphatic-aromatic polyester is composed as follows: b1-i) 30 to 70 mol %, based on components b1-i and b1-ii, of a C6-C18 aliphatic dicarboxylic acid; b1-ii) 30 to 70 mol %, based on components b1-i and b1-ii, of an aromatic dicarboxylic acid; b1-iii) 98 to 100 mol %, based on components b1-i and b1-ii, of 1,3-propanediol or 1,4-butanediol; b1-iv) 0 to 2% by weight, based on components b1-i to b1-iii, of a chain extender and/or branching agent.

2. Laminating film according to claim 1, wherein layer B is composed of: b1) 60 to 100% by weight of an aliphatic-aromatic polyester selected from the group consisting of: Polybutylene adipate-coterephthalate, Polybutylene azelate-coterephthalate and Polybutylene sebacate-coterephthalate; b2) 0 to 15% by weight, preferably 3 to 12% by weight, of a polyhydroxyalkanoate, preferably a polylactic acid; b3) 0 to 25% by weight, preferably 3 to 20% by weight, of a mineral filler.

3. A laminating film according to claim 1, wherein layer A is formed from an aqueous polyurethane dispersion, wherein at least 60% by weight of the polyurethane is composed of: a1) at least one diisocyanate; a2) at least one polyesterol; a3) at least one bifunctional carboxylic acid selected from the group consisting of dihydroxycarboxylic acid and diaminocarboxylic acid; and wherein the glass transition temperature of the polyurethane is below 20 C. or the melting point of the polyurethane is not above 20 C. and has an enthalpy of fusion below 10 J/G.

4. Laminating film according to claim 1, wherein layer B has a layer thickness of 10 to 50 m and contains 0.05 to 0.3% by weight, based on the total weight of layer B, of erucic acid amide.

5. Biodegradable laminating film with the layer structure A/B/C/B, having the layer structure A/B, wherein the 0.5 to 7 m thick layer A comprises a polyurethane or acrylate adhesive; and wherein the 5 to 150 m thick layer B comprises an aliphatic polyester and/or aliphatic-aromatic polyester, wherein the aliphatic-aromatic polyester is composed as follows: b1-i) 30 to 70 mol %, based on components b1-i and b1-ii, of a C6-C18 aliphatic dicarboxylic acid; b1-ii) 30 to 70 mol %, based on components b1-i and b1-ii, of an aromatic dicarboxylic acid; b1-iii) 98 to 100 mol %, based on components b1-i and b1-ii, of 1,3-propanediol or 1,4-butanediol; b1-iv) 0 to 2% by weight, based on components b1-i to b1-iii, of a chain extender and/or branching agent and layer C is a barrier layer consisting of polyglycolic acid, ethylene vinyl alcohol-or preferably polyvinyl alcohol.

6. Laminating film according to claim 5, wherein the barrier layer consists of the individual layers C/C/C and layer C is composed of polyvinyl alcohol and C is an adhesion promoter layer.

7-11. (canceled)

Description

Source Materials

Components of Layer A)

[0121] a-1) Epotal Eco 3702 from BASF SE, waterborne polyurethane dispersion (see PCT/EP2021/054570) [0122] a-2) Epotal P 100 eco from BASF SE, aqueous polyurethane dispersion (see WO 2010/034712)

Components of Layer B)

Component b1):

[0123] b1-1) Polybutylene adipate-coterephthalate: ecoflex F C1200 from BASF SE (MVR at 2.5-4.5 cm.sup.3/10 min (190 C., 2.16 kg) [0124] b1-2) Polybutylene sebacate-coterephthalate: ecoflex FS C2200 from BASF SE (MVR at 3-5 cm.sup.3/10 min (190 C., 5 kg)

Component b2)

[0125] b2-1) Polylactic acid: (PLA) Ingeo 4044 D from NatureWorks (MVR 1.5-3.5 cm.sup.3/10 min (190 C., 2.16 kg))

Component b3)

[0126] b3-1) Plustalc H05C from the company Elementis [0127] b3-2) Calcium carbonate from the company Omya

Component b4)

[0128] b4-1) Erucaic acid amide: Crodamide ER from Croda International Plc. [0129] b4-2) Stearic acid amide Crodamide SRV from the company Croda [0130] b4-3) Behenic acid amide Crodamide BR from the company Croda

Component b5)

[0131] b5-1) Joncryl ADR 4468, glycidyl methacrylate from BASF SE

Components of Layer C)

[0132] c-1 (C) BTR-8002P Adhesion promoter from Mitsubishi Chemicals [0133] c-2 G-polymer BVE8049 PvOH from Mitsubishi Chemicals

Compounding of Layer B

[0134] The compounds listed in Table 1 were produced on a Coperion MC 40 extruder. The temperatures at the outlet were set to 250 C. The extrudate was then pelletized under water. Following pelletizing, the pellets were dried at 60 C.

TABLE-US-00001 TABLE 1 Composition of layer B b1-1 b1-2 b2-1 b3-1 b3-2 b4-1 b4-2 b4-3 b5-1 Weight Weight Weight Weight Weight Weight Weight Weight Weight % % % % % % % % % I 71.9 8 6 14 0.1 II 88.4 9 2.4 0.1 0.1 III 90.7 9 0.2 0.1 IV 87.7 9 3 0.2 0.1 V 75.8 9 15 0.2 VI 75.8 9 15 0.2 VII 75.6 9 15 0.4 VIII 76 9 15

TABLE-US-00002 TABLE 2 Composition of the laminating film Exam- A B C C C B/B Liabil- ple 4 m m Tab. 1 4 m 8 m 4 m 17 m ity* 1 a-1) 17 VIII + 2 a-1) 100 VIII + V-3 a-1) 200 VIII 4 a-1) 17 VIII c-1 c-2 c-1 VIII + 5 a-1) 12 I + 6 a-1) 12 II + 7 a-1) 12 III + 8 a-1) 12 IV + V-9 a-1) 60 IV /+ V-10 a-1) 17 V 11 a-1) 17 VI + 12 a-1) 17 VI c-1 c-2 c-1 V + V-13 a-1) 17 VII

[0135] The base film B was fixed on the laboratory coating table with the corona pre-treated side up and the adhesive to be tested was coated directly onto the film using a squeegee. The adhesive A was dried for 2 minutes with a hot air blower, and then the laminating film was applied with a hand roller and pressed onto a paper of different thickness from 50 gsm to 130 gsm in the roller laminating station at 70 C., with a roller speed of 5 m/minute and a laminating pressure of 6.5 bar. The laminate was then cut into 15-millimeter-wide strips using a cutting template and subjected to various storage cycles. After storage, the laminate strip was pulled apart on the tensile testing machine and the force required to do so was recorded. The test was performed on a tensile testing machine at an angle of 90 degrees with a pull-off speed of 100 mm/min. The test strip was split open on one side, one of the now loose ends was clamped in the upper clamp, the other in the lower clamp of the tensile testing machine and the test started. The rating (+) indicated in the last column of Table 2 means: fiber tear observed. The rating () indicated in the last column means: No fiber tear observed. *The adhesion of the laminating film to the substrate (paper) was determined as follows:

[0136] The tests given in Table 2 show that laminating films containing no release agent b4 in the layer exhibit very good adhesion to the substrate paper up to a total layer thickness of the laminating film of approx. 150 m. If erucic acid amide b4-1 or stearic acid amide b4-2 are used as release agents up to a concentration of 0.3 wt. %, very good adhesion to the substrate paper can be achieved up to a total layer thickness of the laminating films of approx. 50-60 m. If, on the other hand, behenic acid amide b4-3 is used in a concentration of 0.2 to 0.3 wt. % as a release agent, adhesion to the paper is already inadequate at a laminating film thickness of 17 m.

Home Composting Test

[0137] Home compostability is tested according to French standard NF T 51-800 or ISO 14855-1 (2012) Determination of ultimate aerobic biodegradability of plastics under controlled composting conditionsMethod by analysis of evolved carbon dioxide at ambient temperature (282 C.) to simulate home composting conditions instead of the described temperature of 58 C.

[0138] The home compostability of the approximately 60 m thick laminating films of Examples 4 and 12 were investigated under the above conditions and complete (>90%) degradation of the films was observed after 116 days and 157 days, respectively. Thus, these films meet the criterion of home compostability according to the Australian Standard AS 5810-2010 and ISO 14855-1 (2012). It can therefore be assumed that the thinner films with layer structure A/B and a composition of layer B: I, V to VIII (see Table 1) are also home compostable.