PACKAGING

Abstract

Abstract: A container body which comprises a base and a side wall extending from the base, wherein said container body includes a polyester and a polymer YY. wherein said polymer YY is selected from the group comprising cyclic block copolymers (CBC) and cyclic olefin polymers (COP).

Claims

1. A container body which comprises a base and a side wall extending from the base, wherein said container body includes a polyester and a polymer YY.

2. A container body according to claim 1, wherein said polymer YY is such that when dosed at 1 wt% into PET as described in Examples 1 to 4 and bottles produced as described, the transmission, measured as described in Example 4, is reduced to less than 50% of the transmission of the PET alone.

3. (canceled)

4. A container body according to claim 1, wherein the difference between the Tg of the polyester and that of said polymer YY is at least 30° C.; and/or wherein said polymer YY has a Vicat Softening Temperature (VST) measured by ASTM D1525 of at least 110° C.; and/or wherein the difference between the Tg of the polymer YY and said polyester is at least 30° C.

5. (canceled)

6. (canceled)

7. A container body according to claim 1, wherein said polymer YY is selected from the group comprising cyclic block copolymers (CBC) and cyclic olefin polymers (COP).

8. (canceled)

9. A container body according to claim 1, wherein said polymer YY is CBC, wherein said CBC comprises vinyl aromatic monomer units, wherein the hydrogenation level of each vinyl aromatic monomer unit block is greater than 90%; and said CBC includes a conjugated diene monomer unit and the hydrogenation level of the conjugated diene monomer unit is greater than 95%; and/or wherein said CBC has the structure ##STR00004## where R1 and R2 are end groups, and a, b, c, x and v are integers in the range 1 to 100.

10. (canceled)

11. A container body according to claim 1, wherein said polymer YY includes a repeat until of general formula ##STR00005## wherein n is an integer; and/or wherein polymer YY is a COP which includes less than 10 mol% of repeat units of structure —CH.sub.2CH.sub.2—.

12. (canceled)

13. A container body according to claim 1, wherein: a ratio (B) defined as the weight of polyester divided by the weight of polymer YY in a layer of the container body is in the range 8 to 32; said container body is defined by a single layer; and said container body includes 88.0 to 94.0 wt% of polyester, 3.0 to 6.0 wt% of polymer YY and 1.0 to 7.0 wt% of other ingredients.

14. (canceled)

15. (canceled)

16. A container body according to claim 1, wherein: the sum of the wt% of thermoplastic polymers in said container body is at least 88 wt% and the sum is less than 99 wt% ; said container body includes a first light shielding pigment which is zinc sulphide; and said container body includes less than 8 wt% of said first light shielding pigment; and includes at least 1 wt% of said first light shielding pigment.

17. (canceled)

18. (canceled)

19. A container body according to claim 16, wherein: -said container body includes less than 2 wt% of titanium dioxide; and said container body includes a second light shielding pigment which is a particulate metal.

20. (canceled)

21. A container body according to claim 19, wherein said container body includes less than 0.050 wt% of said second light shielding pigment; and the sum of the wt% of light shielding pigments in said container body is less than 5 wt%.

22. (canceled)

23. A container body according to claim 1, wherein said container body includes 88-93 wt% polyester, 1-6 wt% zinc sulphide, 3-7 wt% of polymer YY, 0.01 to 0.2 wt% of particulate aluminium.

24. A container body according to claim 1, wherein said container body includes 88-93 wt% polyester, 2-5 wt% zinc sulphide, 4-7 wt% of polymer YY, 0.01 to 0.10 wt% of particulate aluminium.

25. A container body according to claim 1, wherein: said container body is part of a beverage container, having a volume of no more than 5 litres; and a sidewall of said container body has a thickness of at least 100 microns; and less than 500 microns.

26. A container body according to claim 1, wherein: -said container body has a light transmission (LT%) at 550 nm as described in Test 3 of less than 1.0%; and/or said container body comprises a base, a side wall extending from the base and a neck portion arranged to engage a closure for the container body, wherein said container body includes a polymer YY and polyester, wherein the side wall of the container body has an L* of at least 90 and the neck portion has an L* of at least 84.

27. (canceled)

28. (canceled)

29. A container comprising a container body according to claim 1, wherein a closure is secured to the container body; and said container includes a beverage which includes at least 0.1 wt% fat and/or is a milk.

30. A preform for making a container body, according to claim 1, the preform comprising: (i) a polyester; (ii) a polymer YY.

31. A preform according to claim 30, wherein: -a ratio (A) defined as the weight of polyester divided by the weight of polymer YY in the preform is in the range 8 to 32; and/or said preform includes 88 to 96 wt% of polyester, 3 to 8 wt% of polymer YY and 1 to 7 wt% of other ingredients; and/or comprises a first light shielding pigment which is zinc sulphide (ZnS) and a second light shielding pigment which is particulate metal.

32-36. (canceled)

37. A formulation for use in a method of making a preform according to claim 30, the formulation comprising a polymer YY, wherein said formulation includes 55-64 wt% polymer YY, 30-45 wt% of a first light shielding pigment which is zinc sulphide and 0.10-0.50 wt% of a second light shielding pigment which is particulate metal.

38-41. (canceled)

42. A container body according to claim 1, which comprises a base and a side wall extending from the base, wherein: said container body includes PET and a polymer YY; said polymer YY is selected from the group comprising cyclic block copolymers (CBC) and cyclic olefin polymers (COP); a ratio (B) defined as the weight of PET divided by the weight of polymer YY in a layer of the container body is in the range 15 to 25; said container body is defined by a single layer; and said container body includes 88.0 to 94.0 wt% of PET, 3.0 to 6.0 wt% of polymer YY and 1.0 to 7.0 wt% of other ingredients.

43. A container body according to claim 42, wherein: said container body includes 88-93 wt% PET, 2-5 wt% zinc sulphide, 4-7 wt% of polymer YY and 0.01 to 0.10 wtt% of particulate aluminium. a closure is secured to the container body; and said container includes a beverage which includes at least 0.1 wt% fat and/or is a milk.

Description

[0114] Specific embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

[0115] FIG. 1 is a cross-section through a preform;

[0116] FIG. 2 shows the preform of FIG. 1 superimposed on a bottle blown from the preform to illustrate that a neck of the preform is unchanged on blowing to produce a bottle;

[0117] FIG. 3 includes graphs of light transmission v. wavelength for bottles of Examples 1 to 3.

[0118] The following materials are referred to hereinafter:

[0119] PET-X - refers to a proprietary bottle grade PET (Lighter C93 from Equipolymers, with an Intrinsic Viscosity (IV) of 0.80 +/- 0.02).

[0120] Cyclic block copolymer (CBC) – refers to ViviOn 1325 from USI Group/Mitsui. The material is a block copolymer of styrene and conjugated diene, with the following properties:

TABLE-US-00001 Property Test Method (ASTM) Value Density D792 0.94 g/cm.sup.3 Melt Flow Rate (2.16 kg, 260° C.) D1238 7 cm.sup.3/10 min Vicat softening temperature (1 kg, 50° C./hr) D1525 126° C. Heat distortion temperature (0.455 MPa, 2° C./min) D648 102.5° C.

[0121] Cyclic Olefin polymer (COP) – refers to Zeonor 1420R from Zeon. The material has the following properties:

TABLE-US-00002 Property Test Method Value Glass transition temperature (Tg) JIS K7121 136° C. Melt Flow Rate JIS K6719 (280° C., 21.18 V) 20 g/10 min Flexural Modulus ASTM D790 2200 MPa Vicat Softening Point ASTM D1525 145° C.

[0122] Aluminium paste – refers to STAPA WM Chromal Aluminium flake comprising 80 wt% +/- 2 wt% aluminium pigment and 20 wt% +/- 2 wt% medical white oil and other additives. 98 wt% of the particles can pass though a 45 micron sieve. The D10 is approximately 4 microns; the D50 approximately 13 microns; and the D90 approximately 28 microns.

[0123] Tioxide TR28 – a surface treated fine crystal rutile titanium dioxide obtained from Huntsman.

[0124] Zinc sulphide – SACHTOLITH HD-S supplied by Venator.

[0125] Referring to FIG. 1, a preform 2 for a blow-molded PET bottle 4 (FIG. 2) includes a body 6 which is arranged to expand when the preform 2 is heated in a bottle mold. Above the body 6 is a ring 8 which is generally held by a machine (not shown) during liquid filling of the blow-molded bottle. Above the ring 8 is a cap region 10 with grooves arranged to cooperate with a bottle cap for releasably closing the bottle. Neck region 12 is a portion of the preform 2 which includes cap region 10 and does not expand during blow molding of the preform to produce the bottle. Thus, as illustrated by comparing FIGS. 1 and 2, the neck region 12 is substantially the same size and shape in both the preform and blow-molded bottle. FIG. 2 includes annotated typical preform/bottle dimensions in mm.

[0126] The following tests are referred to herein:

Test 1 - L* A* B* Colour Space Assessment of Preforms

[0127] Preform colour is measured using a Minolta CM2600d spectrophotometer in reflectance mode using D65 illuminant. A preform is positioned on a metal frame (with the main elongate axis of the preform extending substantially horizontally. This allows the spectrophotometer to be positioned in contact with the preform wall at the point of the spectrophotometer aperture. L*, a* and b* values are recorded.

Test 2 - L* A* B* Colour Space Assessment of Blow-Molded Bottle

[0128] A small (60 mm × 60 mm) square section is cut from a bottle wall. This section is placed on the holder of a Minolta CM3600A spectrophotometer, with the outer surface of the bottle section towards the instrument aperture. The Large Area View (LAV) aperture is used, and the colour of the sample is measured in reflectance mode using D65 illuminant. L*,a* and b* values are recorded.

Test 3 - Measurement of Light Transmission of Blow-Molded Bottle

[0129] Light transmission of each bottle is 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.

Examples 1 and 2 - Preparation of Preforms

[0130] Preforms are manufactured in a Husky GL160 injection moulder, with a two cavity mould installed. PET-X (99 wt%) was premixed manually with 1 wt% of selected polymers and manually added into a hopper installed above the feed throat of the injection moulder machine. A standard PET injection moulding process was employed to produce preforms.

[0131] The selected polymers were as follows:

TABLE-US-00003 Example No Selected polymer 1 Cyclic Block Copolymer (CBC) 2 Cyclic Olefin polymer (COP)

Example 3 -Producing Bottles From Preforms

[0132] The preforms of Examples 1 and 2 were stretch blow moulded using a Sidel SB01 blow moulding machine into a 1 litre cylindrical bottle. A standard blowing process was utilised. The overall power % of the heating ovens was adjusted to achieve a preform temperature of 115° -120° C. as the preform exits the oven and before it enters the blow mould. This is referred to as the blowing temperature.

Example 4 - Assessment of Bottles

[0133] A small section was cut from each bottle wall produced as described in Example 3 and the wall thickness measured using a Magna Mike. A typical wall thickness was 200 - 300um. The small sections were then measured for light transmission using a Shimadzu UV Visible Spectrophotometer with an integrating sphere, across the wavelength range 300 - 700 nm. A light transmission of 50% is considered a good result, as it indicates a significant reduction in light transmission compared to a PET-only wall section.

[0134] Results are provided in FIG. 3. The figure shows that addition of the polymers of Examples 1 and 2 to PET-X significantly reduces light transmission (and so increases opacity) of the bottle walls.

[0135] The polymers of Examples 1 and 2 can, in view of the result described, be formulated with other ingredients to produce formulations which can advantageously be used to produce masterbatches, preforms and bottles as described below.

Example 5 - General Procedure for Preparing Masterbatch Formulations

[0136] A premix is prepared where polymer raw materials are weighed and manually mixed together with some of the other materials, aluminium paste and zinc sulphide. The extrusion line is a ZE25UTXi 50D twin screw extruder with a main feeder and a side feeder. The premix is introduced into the extruder via the main feeder and the titanium dioxide (if applicable) is introduced via the side feeder. The extrusion process is a PET process. The strands are cooled down in a water bath and pelletized in a standard pelletizer.

Examples 6 and 7 - Preparation of Masterbatch Formulations

[0137] Following the general procedure referred to in Example 5, a range of masterbatch formulations can be prepared as described below.

TABLE-US-00004 Example No. Identity of polymer Amount of polymer (wt%) Trioxide TR28 (wt%) Zinc Sulphide (wt%) Aluminium paste (wt%) 7 CBC or COP 55.7 11 33 0.3 8 CBC or COP 55.7 0 44 0.3

Examples 8 and 9 - Preparation of Preforms

[0138] The masterbatch formulations of Examples 6 and 7 can be used to produce preforms at a let-down-ratio (LDR) of 9%. 91 wt% of PET-X is compounded with 9 wt% of the formulations of Examples 6 and 7 and preforms manufactured in a Husky GL160 injection moulder machine, with a two cavity mould installed.

[0139] Preform compositions are detailed below.

TABLE-US-00005 Example No. Masterbatch of example used Composition of bottle Amount of polyester PET-X Identity of other polymer Amount of other polymer (wt%) Trioxide TR28 (wt%) Zinc Sulphide (wt%) Aluminium paste (wt%) 8 6 90.97 CBC or COP 5 1 3 0.03 9 7 90.97 CBC or COP 5 0 4 0.03

Examples 10 - Production of Bottles

[0140] Following the procedure referred to in Example 3, the preforms of Examples 8 and 9 can be blown into bottles and assessed. The bottles produced have excellent opacity and whiteness. In addition, the neck portions of the bottles are sufficiently similar in colour to the body of the bottle to be aesthetically acceptable – ie to the naked eye, any differences in colour as between the neck and body of the bottle were not significant enough to lessen the perceived aesthetic acceptability of the bottle.

[0141] 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.