PACKAGING

Abstract

A 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: (i) said container body includes a cyclic olefin copolymer (COC) and polyester; or (ii) said container body includes a polymethylpentene (PMP) and polyester; wherein, in both cases (i) and (ii), 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.

Claims

1. A container body which comprises a base, a side wall extending from the base and a neck portion arranged to engage a closure for the container body, wherein: (i) said container body includes a cyclic olefin copolymer (COC) and polyester; or (ii) said container body includes a polymethylpentene (PMP) and polyester; wherein, in both cases (i) and (ii), 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.

2. A container body according to claim 1, wherein: the difference between the L* of the side wall and the neck portion is less than 12; the L* of the side wall of the container body is least 90; the L* of the neck portion is at least 83; and a first ratio defined as the L* of the side wall of the container body divided by the L* of the neck portion is at least 1.03 and less than 1.15.

3. (canceled)

4. A container body according to claim 1, wherein the difference between the b* of the side wall of the container body and the neck portion of the container body is greater than 1.0 and less than 3.0.

5. 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%.

6. A container body according to claim 1, wherein: a ratio (A) defined as the weight of polyester divided by the weight of COC or PMP in the container body is in the range 8 to 32; and said container body includes 88.0 to 94.0 wt % of polyester, 3.0 to 6.0 wt % of COC and 1.0 to 7.0 wt % of other ingredients; or said container body includes 88.0 to 94.0 wt % of polyester, 3.0 to 6.0 wt % of PMP and 1.0 to 7.0 wt % of other ingredients, preferably in the range 15 to 25.

7. (canceled)

8. (canceled)

9. A container body according to claim 1, wherein: said COC has a glass transition temperature (Tg) (10° C./min) measured as described in ISO 11357-1, -2, -3 of greater than 100° C.; or said PMP has a Vicat softening temperature, measured by ASTM-D1525 (injection moulded specimen (2 mm thick×2pcs), heat speed: 50° C./hour with an applied load of 10N), of 165 to 170° C.; said polyester comprises a polyethylene terephthalate; and the difference between the Tg of the polyester and that of said COC or PMP is at least 30° C.

10. (canceled)

11. (canceled)

12. (canceled)

13. A container body according to claim 1, wherein the sum of the wt % of thermoplastic polymers in said container body is at least 94 wt %; and/or the sum is less than 97 wt %.

14. A container body according to claim 1, wherein said container body includes a first light shielding pigment which is preferably zinc sulphide.

15. A container body according to claim 14, wherein 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.

16. A container body according to claim 15, wherein said container body includes less than 2 wt %, of titanium dioxide; and the sum of the wt % of light shielding pigments in said container body is less than 8 wt %.

17. A container body according to claim 15, wherein said container body includes a second light shielding pigment which is preferably a particulate metal.

18. A container body according to claim 17, wherein said container body includes less than 0.050 wt % of said second light shielding pigment.

19. (canceled)

20. A container body according to claim 1, wherein said container body includes 88-93 wt % polyester, 1-6 wt % zinc sulfide, 3-7 wt % of COC, 0.01 to 0.2 wt % of particulate aluminium.

21. A container body according to claim 1, wherein said container body includes 88-93 wt % polyester, 1-6 wt % zinc sulfide, 3-7 wt % of PMP and 0.01 to 0.2 wt % of particulate aluminium.

22. A preform for making a container body according to claim 1, the preform comprising: (i) a polyester; (ii) a cyclic olefin copolymer (COC) or a polymethylpentene (PMP); wherein: said preform includes 88-93 wt % polyester, 1-6 wt % zinc sulfide, 3-7 wt % of COC, 0.01 to 0.2 wt % of particulate aluminium; or said preform includes 88-93 wt % polyester, 1-6 wt % zinc sulfide, 3-7 wt % of PMP, 0.01 to 0.2 wt % of particulate aluminium.

23-29. (canceled)

30. A formulation for use in a method of making a preform according to claim 22, the formulation comprising a cyclic olefin copolymer (COC) or polymethylpentene (PMP), wherein: said formulation includes a first light shielding pigment and a second light shielding pigment; said formulation includes less than 12 wt % titanium dioxide; and includes 0 wt % of polyester; said formulation includes 40-70 wt % COC or PMP, 20-50 wt % of said first light shielding pigment and 0.05-1 wt % of said second light shielding pigment.

31-37. (canceled)

38. A container body according to claim 1, 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; the L* of the side wall of the container body is least 90 and is less than 98; the L* of the neck portion is at least 83 and less than 88; a first ratio defined as the L* of the side wall of the container body divided by the L* of the neck portion is at least 1.03 and less than 1.15; the difference between the b* of the side wall of the container body and the neck portion of the container body is greater than 1.0 and is less than 3.0; and said container body has a light transmission (LT %) at 550 nm as described in Test 3 of less than 1.0%.

39. A container body according to claim 1, wherein: a ratio (A) defined as the weight of polyester divided by the weight of COC or PMP in the container body is in the range 15 to 25; said container body includes 88.0 to 94.0 wt % of polyester, 3.0 to 6.0 wt % of COC and 1.0 to 7.0 wt % of other ingredients; or said container body includes 88.0 to 94.0 wt % of polyester, 3.0 to 6.0 wt % of PMP and 1.0 to 7.0 wt % of other ingredients; and said polyester comprises a polyethylene terephthalate.

40. A container body according to claim 39, wherein: the difference between the Tg of the polyester and that of said COC is at least 30° C.; said container body includes 88-93 wt % polyester, 1-6 wt % zinc sulfide, 3-7 wt % of COC, 0.01 to 0.2 wt % of particulate aluminium.

41. A container body according to claim 39, wherein said container body includes 88-93 wt % polyester, 1-6 wt % zinc sulfide, 3-7 wt % of PMP and 0.01 to 0.2 wt % of particulate aluminium.

Description

[0122] Specific embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings, in which:

[0123] FIG. 1 is a cross-section through a preform;

[0124] 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;

[0125] FIGS. 3 and 4 are graphs of light transmission v. wavelength for bottles produced.

[0126] The following materials are referred to hereinafter:

[0127] PET-X—refers to a proprietary bottle grade PET (Lighter C93 from Equipolymers, with an Intrinsic Viscosity (IV) of 0.80+/−0.02).

[0128] Comparative Test Material A (CTM-A)—a polyolefin having a Tg of less than 90° C.

[0129] 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.3/10 min ISO 1133 (260° C., 2.16 kg) Tensile modulus (1 mm/min) 2900 Mpa ISO 527-3 Glass transition 142 ° C. ISO 11357-1, -2, -3 temperature (10° C./min) DTUL @ 0.45 MPa 130 ° C. ISO 75-1, -2

[0130] 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.

[0131] PMP (TPX)—refers to polymethylpentene polymer (PMP) sold as TPX RT18 by Mitsui.

[0132] 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.

[0133] The following tests are referred to herein:

Test 1—L*a*b*Colour Space Assessment of Preforms

[0134] 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

[0135] 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

[0136] 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.

EXAMPLE 1—GENERAL PROCEDURE FOR PRODUCING PREFORMS

[0137] Preforms are manufactured in a Husky GL160 injection moulder machine, with a two cavity mould installed. PET is weighed and premixed manually with the COC or PMP (TPX) and any other additives at the required percentages and the mixture manually added into a hopper installed above the feed throat of the machine. A standard PET injection moulding process is employed to produce preforms.

EXAMPLE 2—GENERAL PROCEDURE FOR PRODUCING BOTTLES FROM PREFORMS

[0138] Preforms are stretch blow moulded using a Sidel SB01 blow moulding machine into 1 litre cylindrical bottles.

EXAMPLES 3 AND 4—SCANNING ELECTRON MICROSCOPY (SEM) OF PREFORMS AND BOTTLES

[0139] Using the general procedures referred to in Example 1, preforms were made having the formulations described in the table below.

TABLE-US-00002 Identity of Amount of added Example No. PET-X (wt %) added polymer polymer (wt %) 3 99 CTM-A 1 4 99 Topas 6013-M-07 1

[0140] To analyse preform material, samples were produced by cutting a section of a preform. Each sample was cryo-fractured with liquid nitrogen to reveal the sample's cross-section. The samples were attached to a sample holder using a carbon based tape and a colloidal dispersion of graphite to increase the conductivity. Finally, the sample was metallized with Pd and Au for 45 seconds. SEM was then undertaken.

[0141] To analyse bottles samples for SEM, samples were produced by cutting a section while frozen with liquid nitrogen to reveal the sample's cross-section. The samples were attached to a sample holder using a carbon based tape and a colloidal dispersion of graphite to increase the conductivity. Finally, the sample was metallized with Pd and Au for 45 seconds.

[0142] Respective sections were analysed using SEM at 10.0 k SE (M).

[0143] The SEM analysis of preforms showed that, for both Examples 3 and 4, generally spherical particles of the added polymer in a discreet phase, separate from a PET-X phase, were observable.

[0144] The SEM analysis of blown bottles showed that, for the Example 3 bottle, a homogenous structure was observable and discreet phases seen in the precursor preforms were no longer observed. In contrast, for the Example 4 bottle, generally spherical particles of the added polymer in a discreet phase, separate from the PET-X phase, were still observed.

EXAMPLES 5—LIGHT TRANSMISSION (LT %) OF BOTTLES OF EXAMPLES 3 AND 4

[0145] The light transmission (LT %) of bottles of Examples 3 and 4 were assessed as described in Test 3 and results are provided in FIG. 3 from which it will be seen that the Example 3 material has almost the same light transmission as PET-X alone which suggests that, if a homogenous structure is produced on blowing, negligible opacity is produced; whereas when the COC polymer is present as a discreet phase, separate from a PET-X phase, significantly increased opacity is achieved. Thus, the bottle blown from the preform described in Example 4 was significantly more opaque than that of the bottle blown from the preform of Example 3. In fact, the bottle blown from the preform of Example 3 was less opaque than the preform from which it was blown.

EXAMPLE 6—ESTABLISHING TARGET COLOUR VALUES FOR PREFORMS

[0146] To produce bottles with commercially relevant opacity and/or whiteness, additional additives are included in the formulation of example 4. Applicant was able to achieve high opacity and whiteness (ie high L*) by addition of, for example, titanium dioxide and aluminium flake such as described in co-pending application GB 1915770.0. However, it was also observed that, in some cases, the neck portion of a blown bottle was significantly (and aesthetically unacceptably) darker than the body of the bottle. It was concluded by Applicant that opacity in the stretched bottle wall results from stretching the preform during blow molding and, since the neck portion is not stretched during the blow molding process, its opacity remains the same as in the preform from which it is blown. As a result, with a view to producing commercially acceptable bottles, Applicant developed target colour values for a preform wall (and by extension the neck of a bottle blown from the preform, since the neck in the bottle is unstretched as described, and its colour values are substantially identical to the colour values in the preform). The target colour values are detailed below.

TABLE-US-00003 L* a* b* Target colour values 86.32 −1.23 −1.31 for preform

EXAMPLES 7 AND 8—PREPARATION OF PREFORMS WITH TARGET COLOUR VALUES

[0147] Following the general procedure described in Example 1, preforms were made having the formulations described in the table below.

TABLE-US-00004 COC (Topas 6013-M- Titanium Zinc sulphide Aluminium Example No PET-X (wt %) 07)(wt %) dioxide (wt %) (wt %) paste (wt %) 7 90.97 5 1 3 0.03 8 90.97 5 0 4 0.03

EXAMPLE 9—ASSESSING COLOUR VALUES OF PREFORMS

[0148] Following the procedure referred to in Test 1, the colour values of the preforms of Examples 7 and 8 were assessed for comparison with the target colour values of Example 6. Results are detailed in the table below.

TABLE-US-00005 Example No L* a* b* 7 86.97 −1.23 −1.38 8 85.83 −1.07 −1.14

EXAMPLE 10—PRODUCTION AND ASSESSMENT OF BOTTLES

[0149] Following the procedure referred to in Example 2, the preforms of Examples 7 and 8 were blown into bottles and assessed. Results were as follows:

TABLE-US-00006 Example No L*(D65) a*(D65) b*(D65) 7 93.27 −0.32 −0.17 8 93.42 −0.28 −0.14

[0150] LT % Transmission data for the bottles is provided in FIG. 4 from which it will be noted that the light transmission in both cases is very low.

[0151] The results show that the bottles produced have excellent opacity and whiteness. In addition, the neck portions of the bottles (having the colour values referred to in Example 9) were found to be sufficiently similar in colour to be 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.

EXAMPLES 11 AND 12—SCANNING ELECTRON MICROSCOPY (SEM) OF PREFORMS AND BOTTLES

[0152] Using the general procedures referred to for Examples 3 and 4, preforms were made having the formulations described in the table below.

TABLE-US-00007 Identity of Amount of added Example No. PET-X (wt %) added polymer polymer (wt %) 11 99 CTM-A 1 12 99 PMP (TPX) 1

[0153] Preform material was analysed as described for Examples 3 and 4 and SEM analysis of preforms showed that, for both Examples 11 and 12, generally spherical particles of the added polymer in a discreet phase, separate from a PET-X phase, were observable.

[0154] The SEM analysis of blown bottles showed that, for the Example 11 bottle, a homogenous structure was observable and discreet phases seen in the precursor preforms were no longer observed. In contrast, for the Example 12 bottle, generally spherical particles of the added polymer in a discreet phase, separate from the PET-X phase, were still observed.

EXAMPLES 13—LIGHT TRANSMISSION (LT %) OF BOTTLES OF EXAMPLES 11 and 12

[0155] The light transmission (LT %) of bottles of Examples 11 and 12 were assessed as described in Test 3 and it was found that the Example 11 material has almost the same light transmission as PET-X alone which suggests that, if a homogenous structure is produced on blowing, negligible opacity is produced; whereas when the PMP polymer is present as a discreet phase, separate from a PET-X phase, significantly increased opacity is achieved. Thus, the bottle blown from the preform described in Example 12 was significantly more opaque than that of the bottle blown from the preform of Example 11. In fact, the bottle blown from the preform of Example 11 was less opaque than the preform from which it was blown.

EXAMPLES 14 AND 15—PREPARATION OF PREFORMS WITH TARGET COLOUR VALUES

[0156] Following the general procedure described in Example 1, preforms were made having the formulations described in the table below.

TABLE-US-00008 PMP Titanium Zinc sulphide Aluminium Example No PET-X (wt %) (TPX)(wt %) dioxide (wt %) (wt %) paste (wt %) 14 90.97 5 1 3 0.03 15 90.97 5 0 4 0.03

EXAMPLE 16—ASSESSING COLOUR VALUES OF PREFORMS

[0157] Following the procedure referred to in Test 1, the colour values of the preforms of Examples 14 and 15 were assessed for comparison with the target colour values of Example 6. It was found that the differences in colour values were relatively small and were acceptable.

EXAMPLE 17—PRODUCTION AND ASSESSMENT OF BOTTLES

[0158] Following the procedure referred to in Example 2, the preforms of Examples 14 and 15 were blown into bottles and assessed. Results show that the light transmission in both cases is very low. Additionally, the results show that the bottles produced have excellent opacity and whiteness. In addition, the neck portions of the bottles were found to be 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.

[0159] 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.