PACKAGING

Abstract

A preform is made by mixing cyclic olefin copolymer (COC) and light shielding pigment(s) with PET. The preform is stretch-blow moulded to produce a bottle which may be white and opaque. Light may be restricted from entering the bottle to thereby restrict degradation of the bottle contents from certain wavelengths of visible light.

Claims

1. A container body which comprises: (i) a polymer; and (ii) a cyclic olefin copolymer (COC).

2. (canceled)

3. A container body according to claim 1, wherein a ratio (A) defined as the weight of polymer divided by the weight of COC in the container body is in the range 8 to 65

4. A container body according to claim 3, wherein said ratio (A) is in the range 30-39; or in range 9-15; and said polymer is polyester.

5. A container body according to claim 4, wherein said container body includes 1 to 10 wt % of COC.

6. A container body according to claim 3, wherein said COC includes a repeat unit of formula ##STR00002## which is optionally substituted; and/or a repeat unit of formula
CH.sub.2—CH.sub.2  (II) which is optionally-substituted; wherein said COC includes at least 40 mol % of said repeat unit of formula I and less than 70 mol % of said repeat unit of formula I; and said COC includes less than 60 mol % of said repeat unit of formula II and at least 30 mol % of said repeat unit of formula II.

7. (canceled)

8. A container body according to claim 3, wherein said COC has a glass transition temperature (Tg) of greater than 100° C.

9. A container body according to claim 1, wherein said polymer is a polyester and the sum of the wt % of thermoplastic polymers in said container body is at least 94 wt %.

10. (canceled)

11. A container body according to claim 3, wherein said container body includes a first light shielding pigment, wherein said container body includes no more than 4 wt % of said first light shielding pigment.

12. A container body according to claim 11, wherein said first light shielding pigment is selected from: titanium dioxide (TiO.sub.2), ultramarine blue (PB 29), metal oxide particles such as red iron oxide (PR 101), black iron oxide (PBlk 11), chromium green-black hematite (PG 17), cobalt aluminate (PB 28), aluminium trihydrate (Al(OH)3), barium sulfate (BaSO.sub.4), zinc sulfide (ZnS), metal flake (eg aluminium or bronze flakes), calcium carbonate and mica, wherein said container body includes 1 to 4 wt % of said first light shielding pigment.

13. A container body according to claim 11, wherein said first light shielding pigment is titanium dioxide.

14. (canceled)

15. A container body according to claim 3, wherein said container body includes no more than 4 wt % of titanium dioxide.

16. (canceled)

17. A container body according to claim 12, wherein said container body includes a second light shielding pigment, which is different from said first light shielding pigment, wherein said second light shielding pigment is selected from titanium dioxide (TiO.sub.2), ultramarine blue (PB 29), metal oxide particles such as red iron oxide (PR 101), black iron oxide (PBlk 11), chromium green-black hematite (PG 17), cobalt aluminate (PB 28), aluminium trihydrate (Al(OH)3), barium sulfate (BaSO.sub.4), zinc sulfide (ZnS), metal flake (eg aluminium or bronze flakes), calcium carbonate and mica.

18. (canceled)

19. (canceled)

20. A container body according to claim 1, wherein said container body includes 85-95 wt % polyester, 1-8 wt % titanium dioxide, 1-8 wt % of COC, 0.01 to 1 wt % of aluminium flake or powder and 0 to 1.5 wt % of a polymer which is incompatible/immiscible with the polyester.

21. A container body according to claim 1, wherein said container body includes 85-95 wt % polyester, 1-5 wt % titanium dioxide, 1-7 wt % of COC, 0.01 to 0.5 wt % of aluminium flake or powder and 0 to 1.5 wt % of a polymer which is incompatible/immiscible with the polyester.

22. A container body according to claim 3, wherein said container body has a L* value, measured on the CIELAB scale, of at least 85.

23. A container body according to claim 1, wherein said container body incorporates an oxidizable organic material for scavenging oxygen in use.

24. A preform for making a container body according to claim 1, the preform comprising: (i) a polyester; (ii) a cyclic olefin copolymer (COC).

25. A preform according to claim 24, wherein: the sum of the wt % of polyester(s) and COC(s) in said preform is at least 94 wt %; said preform includes only one layer of material; said preform includes a first light shielding pigment selected from: titanium dioxide (TiO.sub.2), ultramarine blue (PB 29), metal oxide particles such as red iron oxide (PR 101), black iron oxide (PBlk 11), chromium green-black hematite (PG 17), cobalt aluminate (PB 28), aluminium trihydrate (Al(OH)3), barium sulfate (BaSO.sub.4), zinc sulfide (ZnS), metal flake (eg aluminium or bronze flakes), calcium carbonate and mica; said preform includes a second light shielding pigment selected from titanium dioxide (TiO.sub.2), ultramarine blue (PB 29), metal oxide particles such as red iron oxide (PR 101), black iron oxide (PBlk 11), chromium green-black hematite (PG 17), cobalt aluminate (PB 28), aluminium trihydrate (Al(OH)3), barium sulfate (BaSO.sub.4), zinc sulfide (ZnS), metal flake (eg aluminium or bronze flakes), calcium carbonate and mica; said first and second light shielding pigments are different and/or do not include all of the same elements.

26. A preform according to claim 24, wherein: a ratio (C) defined as the weight of polyester divided by the weight of COC in the preform is in the range 8 to 65; a ratio (D) defined as the weight of polyester divided by the weight of COC in a layer of the preform is in the range 8 to 65; said preform includes 1 to 10 wt % of COC and 80 to 99 wt % of polyester; said preform includes an injection moulding which is test-tube shaped; said preform includes a first light shielding pigment which is titanium dioxide.

27. (canceled)

28. (canceled)

29. (canceled)

30. (canceled)

31. (canceled)

32. (canceled)

33. (canceled)

34. (canceled)

35. (canceled)

36. (canceled)

37. A container body which comprises: (i) a polyester; and (ii) a cyclic olefin copolymer (COC); wherein said container body includes 85-95 wt % polyester, 1-8 wt % titanium dioxide, 1-8 wt % of COC, 0.01 to 1 wt % of aluminum flake or powder and 0 to 1.5 wt % of a polymer which is incompatible/immiscible with the polyester; wherein said container body has L* value, measured on the CIELAB scale of at least 85.

Description

[0087] Specific embodiments of the invention will now be described, by way of example, with reference to the accompanying figures in which:

[0088] FIG. 1 is a graph of light transmission (LT %) v. wavelength for various different bottles, as described in Example 1.

[0089] FIG. 2 is a graph of light transmission (LT %) v. wavelength for a for PMP vs COC as formulations as described in Example 2.

[0090] FIG. 3 is a graph of light transmission (LT %) v. wavelength for a series of bottles incorporating different cyclic olefin copolymers;

[0091] FIG. 4 is a graph of light transmission (LT %) v. wavelength for a range of bottles blown at different blowing temperatures; and

[0092] FIG. 5 is a graph of Oxygen Transmission Rate (OTR) v time for bottles which include an oxygen scavenger (AMOSORB™) and a cyclic olefin copolymer or polymethylpentene copolymer.

[0093] The following materials are referred to hereinafter.

[0094] PMP TPX RT18 is a polymethylpentene copolymer, obtained from Mitsui Chemicals Inc.

[0095] Topas 6013 M-07—Cyclic olefin copolymer (COC) obtained from Topas Advanced Polymers. It has the following properties, assessed using the standards referred to:

TABLE-US-00001 Property Value Unit Test Standard Melt volume rate (MVR) 13 cm.sup.3/ ISO 1133 (260° C., 2.16 kg) 10 min Tensile modulus (1 mm/min) 2900 Mpa ISO 527-3 Glass transition temperature 142 ° C. ISO 11357-1, -2, -3 (10° C./min) DTUL @ 0.45 MPa 130 ° C. ISO 75-1, -2

[0096] Topas 5013S-04—Cyclic olefin copolymer (COC) obtained from Topas Advanced Polymers. It has the following properties, assessed using the standards referred to:

TABLE-US-00002 Property Value Unit Test Standard Melt volume rate (MVR) 48 cm.sup.3/ ISO 1133 (260° C., 2.16 kg) 10 min Tensile modulus (1 mm/min) 3200 Mpa ISO 527-3 Glass transition temperature 134 ° C. ISO 11357-1, -2, -3 (10° C./min) DTUL @ 0.45 MPa 127 ° C. ISO 75-1, -2

[0097] Topas 6013S-04—Cyclic olefin copolymer (COC) obtained from Topas Advanced Polymers. It has the following properties, assessed using the standards referred to:

TABLE-US-00003 Property Value Unit Test Standard Melt volume rate (MVR) 14 cm.sup.3/ ISO 1133 (260° C., 2.16 kg) 10 min Tensile modulus (1 mm/min) 2900 Mpa ISO 527-3 Glass transition temperature 138 ° C. ISO 11357-1, -2, -3 (10° C./min) DTUL @ 0.45 MPa 130 ° C. ISO 75-1, -2

[0098] Topas 6015S-04—Cyclic olefin copolymer (COC) obtained from Topas Advanced Polymers. It has the following properties, assessed using the standards referred to:

TABLE-US-00004 Property Value Unit Test Standard Melt volume rate (MVR) 4 cm.sup.3/ ISO 1133 (260° C., 2.16 kg) 10 min Tensile modulus (1 mm/min) 3000 Mpa ISO 527-3 Glass transition temperature 158 ° C. ISO 11357-1, -2, -3 (10° C./min) DTUL @ 0.45 MPa 150 ° C. ISO 75-1, -2

[0099] Topas 6017S-04—Cyclic olefin copolymer (COC) obtained from Topas Advanced Polymers. It has the following properties, assessed using the standard referred to:

TABLE-US-00005 Property Value Unit Test Standard Melt volume rate (MVR) 1.5 cm.sup.3/ ISO 1133 (260° C., 2.16 kg) 10 min Tensile modulus (1 mm/min) 3000 Mpa ISO 527-3 Glass transition temperature 178 ° C. ISO 11357-1, -2, -3 (10° C./min) DTUL @ 0.45 MPa 170 ° C. ISO 75-1, -2

[0100] In general terms, PET-based bottle preforms are made by mixing materials with the PET which are intended to make a finished bottle made from the preform, appear white and opaque. The objective is to block light entering the bottle to prevent (or at least restrict) degradation of the bottle contents from certain wavelengths of visible light (in the range 300-700 nm).

[0101] The materials to be mixed with the PET are suitably provided as solid masterbatch pellets which is melt processed with the PET to produce a preform which is subsequently stretch-blow moulded to produce a bottle.

[0102] As will be apparent from the examples which follow, cyclic olefin copolymer (COC) has been found, in use, to be unexpectedly better at blocking light entering a bottle and/or has other advantageous properties compared to prior art materials.

[0103] In the following examples, Example 1 compares PET bottles incorporating various light blocking polymers; Example 2 makes comparisons of various light blocking formulations; Examples 3 and 4 assess colour of bottles incorporating various light blocking formulations; Example 5 assesses a range of alternative COCs; and Example 6 assesses bottles blown from preforms at differing blowing temperatures.

Example 1—Comparison of PET Bottles Incorporating Light-Blocking Polymers

[0104] PET-based bottles were made including COC, high impact polystyrene (HIPS) and/or TPX RT18. PP and HIPS were selected since they are referenced in prior patents. TPX RT18 is an example of a polymethylpentene (PMP) as described in prior publications WO2019/117725 and WO2019/133713.

[0105] Preforms were manufactured in a Husky GL160 injection moulder, with a two cavity mould installed. PET is weighed and premixed manually with the additional polymer at the required percentage and manually added into a hopper installed above the feed throat of the machine. A standard PET injection moulding process was employed to produce preforms. The resulting preforms were then stretch blow moulded using a Sidel SB01 blow moulding machine into 1 litre cylindrical bottles.

[0106] Details on the examples are provided in the table below.

TABLE-US-00006 Example Additional polymer wt % of additional polymer No. included with PET included 1a No additional polymer — 1b PP 1 1c HIPS 1 1d TPX RT18 (PMP) 1 1e Topas 6013 M (COC) 1

[0107] Light transmission of each bottle was assessed on a cut section from the bottle wall, using a Shimadzu UV Visible Spectrophotometer with an integrating sphere, across the wavelength range 300-700 nm.

[0108] Results are provided in FIG. 1 which shows that PP and HIPS are not as effective alone at blocking light when compared to the COC and PMP materials. Advantageously, the light transmission when COC is used (Example 1e) is lowest (meaning light blocking is highest).

Example 2—Comparisons of Light Blocking Using Various Light-Blocking Formulations

[0109] Masterbatch formulations, based on formulations described in EP3023458A (and incorporating COC or PMP, the latter for comparison purposes), were prepared as described in the table below.

TABLE-US-00007 Example No. 2a 2b 2c 2d HIPS 7.8 7.8 PMP RT18 59.23 26 COC 6013M-07 59.23 26 Titanium Dioxide white pigment 40 65 40 65 Iron Oxide black pigment 0.07 0.07 Aluminium paste 0.7 1.2 0.7 1.2 TOTAL 100 100 100 100

[0110] As will be appreciated, Examples 2a and 2c are directly comparable (they differ only in the identity of polymers incorporated—i.e. PMP or COC) and examples 2b and 2d are directly comparable (they too differ only in the identity of polymers incorporated—i.e. PMP or COC).

[0111] Preforms were made using a Husky GL160 injection moulder and preforms subsequently blown as described in Example 1. The preforms made from examples 2a and 2c masterbatches included 10 wt % of the masterbatches; and the preforms made from examples 2b and 2c masterbatches included 6 t % of the masterbatches. The masterbatch addition rates were selected to ensure the blown bottles included no more than 4 wt % of titanium dioxide.

[0112] The light transmission of the blow bottles of Examples 2a and 2c were assessed as described in Example 1 and results are presented in FIG. 2. The figure shows that the bottle incorporating the formulation of Example 2c (which includes COC) has better light blocking compared to the comparative Example incorporating the formulation of Example 2a (which includes PMP).

Example 3—Colour Comparisons of Bottles Including Light-Blocking Formulations

[0113] The colours of bottles incorporating PMP or COC and being made as described in Example 2 were assessed using a Minolta CM3600d spectrophotometer in reflectance mode. Results are provided for L*, a* and b* in the table below.

TABLE-US-00008 Masterbatch Example formulation of Mean L* Mean a* Mean b* No. Example No. (D65) (D65) (D65) 3a 2a at 10 wt % 92.64 −0.57 −0.29 3b 2c at 10 wt % 93.80 −0.42 0.12 3c 2b at 6 wt % 89.84 −1.08 −1.56 3d 2d at 6 wt % 92.37 −0.73 −0.72

[0114] It should be noted from the results that the COC-based formulation of Example 3b has a higher L* in comparison to the PMP-based formulation of Example 3a; and, similarly, the COC-based formulation of Example 3d has a higher L* compared to the PMP-based formulation of Example 3c. In addition, the COC-based formulations lead to lower b values (less blue colour) which is preferred.

[0115] Thus, advantageously, COC-based formulations have improved lightness and/or colour relative to comparable examples.

Example 4—Colour Comparison in Formulation with Titanium Dioxide

[0116] The colours of PET bottles incorporating PMP or COC and 4 wt % titanium dioxide, made as described in Example 1, were assessed as described in Example 2. Results are provided in the table below. Note that Comparative Example 4a is a commercially available product of the type described in EP 3023458 A.

TABLE-US-00009 Example Detail on Mean L* Mean a* Mean b* No. composition (D65) (D65) (D65) 4a Commercially 91.16 −1 −1.97 available product of type described in EP 3023458 A 4b TiO.sub.2 (4 wt %), 96.41 −0.38 1.61 COC (4 wt %), balance PET

[0117] It should be appreciated that, compared to Example 4a, Example 4b (which includes COC) is significantly lighter (higher L*) and yellower (higher b*).

Example 5—Assessment of Alternative COCs

[0118] Following the procedure described in Example 1, PET-based bottles were made including a number of alternative commercially-available COCs, as follows:

TABLE-US-00010 Example No. COC 5a Topas 5013S-04 5b Topas 6013S-04 5c Topas 6015S-04 5d Topas 6017S-04 5e No COC

[0119] FIG. 3 includes results of light transmission (LT %) v. wavelength for the examples. Incorporation of each of the COCs is found to significantly reduce light transmission.

Example 6—Assessment of Bottles Blown from Preforms at Different Blowing Temperatures

[0120] A number of identical PET preforms were made incorporating 1 wt % of Topas 6013M and the preforms were then blown on a Sidel SB01 blowing machine. The oven profile was set to achieve a good quality bottle with a uniform material distribution. The overall power of the ovens was adjusted by increasing the AL+ % figure, to increase the preform temperature as it exited the ovens and before it entered the blow mould (the blowing temperature). The higher the AL+ %, the higher the preform temperature.

[0121] Light transmission was checked on a cut section from the bottle wall using a Shimadzu UV Visible Spectrophotometer with an integrating sphere, across the wavelength range 300-700 nm. Wall thickness was measured using a Magna Mike.

[0122] The table below details bottles assessed.

TABLE-US-00011 Example Blowing temperature Wall thickness No (° C.) (μm) 6a 108 313 6b 120 293 6c 140 302 6d 150 317

[0123] Results are provided in FIG. 4 which shows that, when the blowing temperature is high (about 150° C. as in Example 6d), the opacity is greatly reduced (i.e. the light transmission LT % is high). Opacity increases as the blowing temperature is reduced (see Example 6c) but there comes a point where reducing blowing temperature beyond a certain limit (e.g. 140° C.—compare Examples 6a and 6b) has minimal effect on light transmission (LT %)—i.e. the LT % is almost identical for Examples 6a and 6b.

[0124] It is believed the effect of blowing temperature may be related to the glass transition temperature (Tg) of the COC. As described above, the COC has a Tg of 142° C. Thus, Applicant concludes that it is preferred for the bottle to be blown at a temperature below the Tg of the COC and preferably 10 to 20° C. below the Tg.

[0125] Thus, COCs as described are advantageous when used in PET bottles and may be used to protect the contents of such bottles, with the bottles advantageously appearing white.

Example 7—Assessment of Effect of COC and PMP on Oxygen-Scavenging Polymer

[0126] Bottles were blown from preforms including 5 wt % AMOSORB 4020E, a commercially available oxygen scavenging formulation which includes polybutadiene moieties and is of a type described in U.S. Pat. No. 6,083,585, in combination with either a COC or PMP. The bottles were then assessed using standard techniques to determine how long it took for the AMOSORB to be activated (ie to start scavenging oxygen in the bottle). Results are provided in FIG. 5 which show that for the COC-containing bottle the AMOSORB is activated normally (ie rapidly), whereas, disadvantageously, for the PMP-containing bottle there is a substantial delay before the AMOSORB is activated.

[0127] The invention is not restricted to the details of the foregoing embodiment(s). The invention extends to any novel one, or any novel combination, of the features disclosed in this specification (including any accompanying claims, abstract and drawings), or to any novel one, or any novel combination, of the steps of any method or process so disclosed.