A CONTAINER

Abstract

The present invention relates to a container comprising a film substrate, wherein the film substrate comprises graphene or derivative thereof and an adhesive. It further describes method for preparing the container comprising steps of preparing a suspension of graphene or derivative thereof in solvent, providing an adhesive layer, coating the adhesive layer with the suspension, and allowing the solvent to evaporate.

Claims

1. A container comprising a film substrate, wherein the film substrate comprises graphene or derivative thereof and a pressure sensitive adhesive.

2. A container according to claim 1 wherein the pressure sensitive adhesive is a natural rubber-based adhesive.

3. A container according to claim 1 wherein the container comprises paper.

4. A container according to claim 1 wherein the container comprises a plastic material.

5. A container according to claim 1 wherein the graphene derivative is graphene oxide.

6. A container according to claim 1 wherein the container is a substantially rigid container.

7. A container according to claim 1 wherein the container is a flexible pouch.

8. A container according to claim 7 wherein the container is a unit dose capsule.

9. A method for preparing a container comprising a film substrate, the method comprising the steps of preparing a suspension of graphene or derivative thereof in a solvent, providing an adhesive layer to the outer surface of the container, coating the adhesive layer with the suspension, and allowing the solvent to evaporate thereby providing the film substrate residing on the outer surface of the container.

Description

[0058] Embodiments of the invention are now described with reference to the following non-limiting examples in which FIG. 1 illustrates a stand-up pouch and FIG. 2 illustrates a bottle.

[0059] FIG. 1a provides an overview of a stand-up pouch (1) and FIG. 1b provides cross-section of the pouch. The pouch has a polymer layer (11) as inner most layer. An adhesive layer (12) is adhered to the polymer layer (11). Graphene oxide particles are applied on to the adhesive layer (12). The pouch is formed by sealing the polymer layers (11) at the sides (14).

[0060] FIG. 2a illustrates the invention with an example of a bottle. FIG. 2b provides cross-section the bottle. The bottle (2) has polymer layer (21). An adhesive (22) is provided on the outer surface of the polymer layer (21). Graphene oxide particles (23) are applied on to the adhesive layer (22). Thickness of the layers on both figures are not up to the scale and figures are only for illustration purposes. Figures do not limit the scope of the invention.

[0061] Embodiments of the invention are further described with reference to the following non-limiting examples.

EXAMPLES

Example 1

[0062] To evaluate the performance of the container, a detergent tablet was prepared according to below recipe:

TABLE-US-00001 Ingredients Wt. % Surfactants (Mixture of LAS, SLES, MES) 13.86 Sodium carbonate 26.96 Sodium sulphate 28.00 Other fillers (Salt, clays) 16.00 Disintegrant 12.00 Moisture/minors 3.18 TOTAL 100

[0063] The ingredients were dry mixed and compressed to form a tablet by applying direct compression.

[0064] At first, a film substrate comprising graphene oxide was prepared, by dispersing 50 mg of graphene oxide (ex. Platonic Nano Tech) in 15 mL water. The dispersion was spray coated on 14 cm xl 0 cm area PSA paper (TESA 4302) and dried at 50° C. for 3 hrs.

[0065] A container according to the present invention was formed by taking a tablet prepared by aforesaid process and wrapped it with the film substrate. Comparative container was formed by wrapping a tablet with a paper without graphene oxide and pressure sensitive adhesive.

[0066] To evaluate the efficacy, containers with tablets are stored in hot and humid (37° C., 85% humidity) condition. A tablet without any wrap was also stored along with the containers as control. Tablets were taken out from the container after regular interval and moisture contents of the tablets were evaluated.

TABLE-US-00002 Initial Moisture After Tablet content 2 days After 7 days Detergent control Tablet 7 — Didn't sustain as the entire tablet failed Detergent tablet in 7 18 Didn't sustain as the pure paper without entire tablet failed graphene oxide Detergent tablet in paper, 7 — 11 PSA, graphene oxide

[0067] With paper and PSA but no graphene oxide was not performed as the material is too sticky for commercial applications.

Example 2

[0068] To evaluate the barrier property of the container, a container with a film substrate was prepared with graphene oxide and polyvinyl alcohol, pressure sensitive adhesive and paper.

[0069] PVA with graphene oxide suspension was prepared according to below recipe

TABLE-US-00003 Ingredients (g) (%) PVA (98% hydrolyzed) Mw 31-50 kDa 0.3 PVA (88% hydrolyzed) Mw 85-124 kDa 1.2 Total PVA 1.5 90.5 Plasticizer (PEG-200) 0.15 9.05 Graphene oxide (5 ml of 0.167%) 0.0083 0.5 Total 1.675 100

[0070] 1.5 g of PVA (mixture of two molecular weights) is added to 15 mL water to make an aqueous solution. The mixture was heated to 80° C., with stirring at 300 rpm until homogeneous solution is achieved.

[0071] To the above mixture, 0.15 g plasticizer (PEG-Mw 200) was added, mixed for 5 mins, and cooled down to room temperature.

[0072] 5 mL of the 0.167% Graphene Oxide (GO) dispersion was added to the polymer resin after cooling, and mixing is continued.

[0073] 10 mL of the suspension was casted on the TESA 4302 paper (contained in a tray) and dried at 50° C. for 3 hours. The dimension of the paper was 14 cm×10 cm.

[0074] The container was transparent unlike the previous case. PVA is one example but not limited by the polymer. The requirement for the polymer is it must intercalate with GO and form stable suspension and film should form upon drying. All polymers which are used for solvent-casting route is applicable for this.

[0075] Barrier properties of the container with the film were evaluated in terms of Water Vapour Transmission Rate (WVTR)

TABLE-US-00004 Film Composition WVTR (g/day .Math. m.sup.2) PVA (control) 84.4 PVA + GO (0.03%) 32.0

[0076] The container comprising a film with graphene oxide shows improved WVTR, which implies better barrier properties.