Pack for anaerobic products

Abstract

A pack comprising: a container, the container having a container body, and the container body being sufficiently oxygen permeable to prevent an anaerobically curable composition held therein from curing due to absence of oxygen; and an anaerobically curable composition held within the container is provided. The container body is constructed from a plastics material which is formed from a blend of a thermoplastic starch component and a polyethylene.

Claims

1. A pack comprising: a. a container, the container having a container body; and b. an anaerobically curable composition held within the container; wherein the container body is constructed from plastics material which is formed from a blend of a thermoplastic starch component, wherein the starch in the thermoplastic starch component is present in an amount from 6% to 33% of the weight of the blend used to form the container body and a polyethylene, and which is sufficiently oxygen permeable to prevent the anaerobically curable composition held therein from curing due to absence of oxygen.

2. A pack according to claim 1 wherein the starch in the thermoplastic starch component is sourced from a renewable source.

3. A pack according to claim 1 wherein the starch in the thermoplastic starch component is present in an amount from 13% to 32% of the weight of the blend used to form the container body.

4. A pack according to claim 1 wherein the starch in the thermoplastic starch component is present in an amount from 20% to 30% of the weight of the blend used to form the container body.

5. A pack according to claim 1 wherein the starch in the thermoplastic starch component is present in an amount from 23% to 30% of the weight of the blend used to form the container body.

6. A pack according to claim 1 wherein the starch in the thermoplastic starch component is present in an amount of about 26% of the weight of the blend used to form the container body.

7. A pack according to claim 1 wherein the polyethylene is present in an amount from 66% to 94% of the weight of the blend used to form the container body.

8. A pack according to claim 1 wherein the polyethylene is present in an amount from 67% to 87% of the weight of the blend used to form the container body.

9. A pack according to claim 1 wherein the polyethylene is present in an amount from 70% to 80% of the weight of the blend used to form the container body.

10. A pack according to claim 1 wherein the polyethylene is present in an amount of about 74% of the weight of the blend used to form the container body.

11. A pack according to claim 1 wherein the oxygen permeability of the container body is at least 2.4 cm.sup.3 in 24 hours based on a wall thickness of 4 mm.

12. A pack according to claim 1 wherein the viscosity of the anaerobically curable composition is from about 10 centipoise to about 8,000 centipoise.

13. A pack according to claim 1 wherein the polyethylene is LDPE.

14. A pack according to claim 1 wherein the blend from which the container body is formed comprises a plasticiser.

15. A pack according to claim 1 wherein the container body is squeezable for dispensing the anaerobically curable composition.

16. A pack according to claim 1 wherein the container body is a bottle.

17. A pack according to claim 1 wherein the container further comprises a dispensing nozzle, for dispensing the anaerobically curable composition from the container.

18. A pack according to claim 1 wherein the container further comprises a dispensing closure for dispensing the anaerobically curable composition from the container.

19. A pack according to claim 1 wherein the container body is coloured by a pigment.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Embodiments of the invention will be described, by way of example only, with reference to the accompanying drawings in which:

(2) FIG. 1 is an image of (red) coloured 50 ml bottle made and tested in the experimental below; and

(3) FIG. 2 is a graph showing the results of flexibility testing that was conducted on a bottle such as that shown in FIG. 1 and as set out below.

DETAILED DESCRIPTION OF THE DRAWINGS

(4) FIG. 1 shows an image (photo) of a (red) coloured 50 ml bottle made and tested in the experimental below. A ruler is included in the image to give an indication of scale. (A similar bottle was made to hold 250 ml of product as set out below.)

(5) A blend of polyethylene and a thermoplastic starch were utilised to form container bodies. Thereafter packs were formed utilising the container bodies and a closure for the container. Specifically anaerobically curable adhesive was placed in the container. The containers were found to demonstrate comparable storage stability to that demonstrated by a comparable container formed from PE alone.

(6) All Loctite? products are available from Henkel Ireland, Tallaght Business Park, Whitestown, Tallaght, Dublin 24.

(7) The following is a discussion of the creation of packs, tests carried out and the results of those tests:

EXPERIMENTAL

(8) Packs which are in the form of bottles with anaerobic curable adhesive located therein are sold with what is often termed a minimum product fill volumethe containers are not filled to the top, rather a substantial headspace is left in the container. For example packs have been sold with respective fills of 50 ml & 250 ml of anaerobic product even though the containers themselves have a much greater capacity for example internal volumes of approximately 106 ml & 445 ml respectively. The additional headspace is required in order to keep the products stable via access to oxygen.

(9) Existing bottles in both sizes made from 100% LDPE and alternatives made up of 60% of the same LDPE and 40% Cardia BLF02 (Cardia BL-F02 is a commercially available blend of thermoplastic starch and polyethyleneavailable from Cardia Bioplastics Unit 18/35 Dunlop Road Mulgrave, Victoria 3170, Australia) had 50 ml or 250 ml of product placed therein. The products for which specified tests were conducted are Loctite? products 270, 243, 242, 278, 290, 542, 549, 601, 638, 648, 649, 2700, 2400, and 6300 as indicated in Table 1 below.

(10) Cardia BL-F02 is a thermoplastic starch material comprising starch; glycerol; sorbitol; polyethylene-co-acrylic-acid and polyethylene. Cardia BL-F02 is approximately (by weight) 66% starch, 30% polyethylene, and the remaining 4% is glycerol; sorbitol; and polyethylene-co-acrylic-acid.

(11) The bottles were sealed with closures after filling.

(12) Bottles were produced by a two cavity mould on a twin head extrusion blow moulding machine. The bottles made utilising the 40% Cardia BLF02 had the following dimensions and had 50 ml of anaerobic product placed inside:

(13) TABLE-US-00001 50 ml Cardia 40% trial 21.01.14 Cavity number 430.1 430.2 Overall Height 106.00 ? 1.00 mm 105.95 106.00 Overall Width 57.20 ? 1.00 mm 57.65 57.69 Overall Depth 28.00 ? 1.00 mm 28.26 28.30 Neck Height 13.70 ? 0.40 mm 13.75 13.76 T Dimension Outside 23.10 ? 0.20 mm 23.11 23.10 T Ovality Threads 0.40 Max mm 0.27 0.31 E Dimension Inside 21.10 ? 0.20 mm 21.11 21.23 E Ovality Threads 0.40 Max mm 0.21 0.19 I Dimension Internal 17.70 ? 0.20 mm 17.72 17.70 I Ovality Neck 0.40 Max mm 0.21 0.20 S Dimension Thread Start 1.70 ? 0.40 mm 1.39 1.42 Thread Pitch 3.00 ? 0.10 mm 2.98 2.98 Thread Height 2.00 ? 0.10 mm 2.06 2.07 Wall Thickness (Min) 0.25 0.47 0.44 Leak Test P/F Pass Pass Brimfull Capacity 107.00 ? 6.00 ml ? ? Bottle Weight 13.00 ? 1.50 gm 14.50 14.39 Dishing Max top 28.37 28.50 Min 28.08 28.18 Max base 28.33 28.23 D 0.14 0.09

(14) The bottles made utilising the blend with 40% Cardia BLF02 had the following dimensions and had 250 ml of anaerobic product placed inside:

(15) TABLE-US-00002 250 ml Cardia 40% trial 21.01.14 Cavity number 429.10 Overall Height 169.60 ? 2.50 mm 169.95 Overall Width 91.50 ? 1.50 mm 91.86 Overall Depth 45.00 ? 1.00 mm 45.39 Neck Height 14.20 ? 0.40 mm 14.15 T Dimension Outside 23.10 ? 0.20 mm 23.16 T Ovality Threads 0.40 Max mm 0.10 E Dimension Inside 21.10 ? 0.20 mm 21.24 E Ovality Threads 0.40 Max mm 0.17 I Dimension Internal 17.70 ? 0.20 mm 17.71 Neck 0.40 Max mm 0.07 S Dimension Thread Start 1.70 ? 0.40 mm 1.52 Thread Pitch 3.00 ? 0.10 mm 2.98 Thread Height 2.00 ? 0.05 mm 2.05 Wall Thickness (Min) 0.25 mm 0.58 Leak Test P/F Pass Brimfull Capacity 445.00 ? 10.00 ml ? Bottle Weight 36.00 ? 1.50 gm 36.47 Dishing Max top 45.08 Min 45.12 Max base 45.25 D 0.02

(16) Filled samples were then subjected to both accelerated (35? C. & 45? C./98% relative humidity) and real time (22? C.often referred to generically as room temperature, RT) ageing test programs as follows:

(17) 4 wks @ 45? C./98% RH

(18) 8 wks @ 35? C.

(19) 16 wks @ 35? C.

(20) 6 mths @ 22? C.

(21) 12 mths @ 22? C.

(22) 18 mths @ 22? C.

(23) 24 mths @ 22? C.

(24) Length of real time ageing at 22? C. is dependent on shelf life of product, which in most cases is 24 mths.

(25) The products and their specific test points are set out in Table 1 below. (At the time of filing this application the 18 and 24 months testing were still ongoing, but performance to date is similar to that of conventional LDPE bottles.) The products and their test results are set out in Table 2 below. A performance result equivalent to an LDPE bottle is considered to be a positive result.

(26) Once test points are completed both sets of bottles are examined and visually compared for any evidence of gelling of product and/or deterioration of packaging and/or evidence of leakage.

(27) Then samples were tested to ensure that required performance was being met. For this standard test methods STM-754, STM-8, STM-701 & STM-734 were used.

(28) Unfilled bottles were subjected to Flexibility testing & Oxygen Transmission Rate measurements in comparison with LDPE & HDPE. They were also measured dimensionally to ensure they were within specification as indicated in the tabulated dimensions for each bottle.

(29) Oxygen Transmission testing (OTR) was determined in accordance with ASTM F1307-02 using Mocon Oxtran 2/21 equipment with a coulometric sensor. The bottles were mounted such that the inside was purged for 12 hrs by a stream of nitrogen while the outside was exposed to air (20.8% Oxygen) at 23? C., 50% RH. The bottles were tested using the converge mode. Equilibrium is established when the current transmission rate is less than 1% difference between the transmission rate obtained 5 cycles (30 minute/cycle) previous to the current transmission rate.

(30) The result is quoted for 100% Oxygen. Four samples were tested for each bottle type. The integrity of the mounted bottles were checked prior to test using an Ai Leakmeter 120 electron-capture gas detector. The results are as follows.

(31) TABLE-US-00003 O2 transmission rate (cc/pack day to 100% O2) Average Purell LDPE 2.78 2.85 2.55 2.7 2.7 Marlex HDPE 1.34 1.64 1.45 1.63 1.5 Cardia BLF02 40%/Purell 2.66 2.46 1.66 2.69 2.4 LDPE 60%

(32) Purell is a brand name for product available from Lyondell Bassell, Houston, Tex., USA.

(33) Marlex is a brand name for product available from Phillips Chemical International N.V., Overijse, Belgium.

(34) Flexibility of bottles was determined on a TA-XT2i Stable Microsystems Texture Analyser using a P/2N stainless steel probe. Test speed was set at 0.5 mm min and distance from central position was set at 6.5 mm. Bottle was laid flat on the plate in horizontal position with the probe facing down in vertical orientation. Connected probe was set at a starting position where no load is being applied to the face of the bottle wall. Unit was run at test speed until target distance was reached and graph produced of output values (Force/Kg) versus distance to compare the flexibility. Three samples of each bottle type was measured.

(35) The results of this testing for a 50 ml bottle are set out in FIG. 2. The 250 ml bottle was assumed to have equivalent oxygen transmission.

(36) TABLE-US-00004 TABLE 1 Product Test points Loctite 270 All test points Loctite 243 All test points Loctite 242 6 & 12 mths @ 22? C. only Loctite 278 6 & 12 mths @ 22? C. only Loctite 290 All except 6 mths @ 22? C. Loctite 542 6 & 12 mths @ 22? C. only Loctite 549 No 4 wks @ 45? C./98% RH. Shelf life 12 mths @ 22? C. Loctite 601 All test points Loctite 638 All except 4 wks @ 45? C./98% RH Loctite 648 All except 4 wks @ 45? C./98% RH Loctite 649 All test points up to 12 mths @22? C. (shelf life) Loctite 2700 All test points up to 18 mths @ 22 C. (shelf life) Loctite 2400 All test points up to 18 mths @ 22 C. (shelf life) Loctite 6300 All test points up to 12 mths @22? C. (shelf life)

(37) TABLE-US-00005 TABLE 2 Test method STM-734 STM-754 STM-701 Fixture STM-8 Product Shear strength Break Torque test Stab test Result Loctite 270 Mild steel pins & collars Mild & Stainless steel N/A No Results within specification and/or equivalent to LDPE bottles nuts & bolts Loctite 243 Mild steel pins & collars Mild steel nuts & bolts N/A No Results within specification and/or equivalent to LDPE bottles Loctite 242 N/A Mild steel nuts & bolts N/A No Results within specification and/or equivalent to LDPE bottles Loctite 278 Mild steel pins & collars Zinc phosphate nuts & Brass nuts No Results within specification and/or equivalent to LDPE bottles bolts & bolts Loctite 290 Mild steel pins & collars Mild steel nuts & bolts N/A No Results within specification and/or equivalent to LDPE bottles Loctite 542 Mild steel pins & collars N/A N/A No Results within specification and/or equivalent to LDPE bottles Loctite 549 N/A Mild steel nuts & bolts N/A No Results within specification and/or equivalent to LDPE bottles Loctite 601 Mild steel pins & collars Mild steel nuts & bolts N/A No Results within specification and/or equivalent to LDPE bottles Loctite 638 Mild & stainless steel N/A N/A Yes Results within specification and/or equivalent to LDPE bottles pins & collars Loctite 648 Mild steel pins & collars N/A N/A Yes Results within specification and/or equivalent to LDPE bottles Loctite 649 Mild steel pins & collars N/A N/A No Results within specification and/or equivalent to LDPE bottles Loctite 2700 Mild steel pins & collars Mild steel nuts & bolts N/A No Results within specification and/or equivalent to LDPE bottles Loctite 2400 Mild steel pins & collars Mild steel nuts & bolts N/A No Results within specification and/or equivalent to LDPE bottles Loctite 6300 Mild steel pins & collars N/A N/A No Results within specification and/or equivalent to LDPE bottles

CONCLUSION

(38) The bottles prepared according to the experimental above, clearly show that the pack of the invention provides an overall stability which is equivalent to existing packs (such as LDPE). Furthermore, the bottles were shown to be compatible with the contents therein. No issues arose with premature curing/gelling of the product in the container. Furthermore, the containers were slightly easier to squeeze. And this was shown over a wide range of products of differing compositions.

(39) Overall then, the bottles formed from the blending of the thermoplastic starch with LDPE provided the same performance as equivalent 100% LDPE bottles in terms of product stability and compatibility, performance, oxygen transmission and are slightly easier to squeeze.

(40) The words comprises/comprising and the words having/including when used herein with reference to the present invention are used to specify the presence of stated features, integers, steps or components but do not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof.

(41) It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.