Method for depositing liquid onto the locking ring of a container

Abstract

The invention provides: a method for applying a liquid to the rim of a container by transfer from a roller whose surface is composed of a tubular warp or weft knit of 21 rib construction; a glass jar or equivalent container whose rim has a coating of varnish, adhesion promoter or heat-sealing primer formed by an application method; a jar or equivalent container comprising a seal heat-sealed to the rim.

Claims

1. A method for applying a liquid to a rim of a container, the method comprising: contacting a rim of a container with a roller comprising a liquid, thereby transferring the liquid to the rim of the container, wherein a surface of the roller comprises a tubular warp or weft knit, and the knit comprises a yarn having a metric number of between 1/002 Nm and 1/080 Nm wherein the container is a glass jar, a glass bottle, a glass flask, or a glass decanter, and wherein the liquid is an adhesion promoter or a heat-sealing primer.

2. The method of claim 1, wherein the knit has a rib construction.

3. The method of claim 2, wherein the knit has a 21 rib construction.

4. The method of claim 1, wherein the knit comprises a natural or synthetic fiber.

5. The method of claim 4, wherein the knit comprises a para-aramid fiber.

6. The method of claim 1, wherein the knit comprises a yarn having a metric number of between 1/010 Nm and 1/080 Nm.

7. The method of claim 1, wherein the tubular knit directly covers a fabric, or a foam or a material which is resilient.

8. The method of claim 7, wherein the fabric is a denim and the foam or the material which is resilient is a solid or cellular silicone or rubber.

9. The method of claim 7, wherein the tubular knit directly covers a denim fabric.

10. The method of claim 7, wherein the tubular knit directly covers a solid or cellular silicone.

11. The method of claim 7, wherein the tubular knit directly covers a solid or cellular rubber.

12. The method of claim 1, wherein the knit comprises a natural fiber.

13. The method of claim 1, wherein the knit comprises a synthetic fiber.

14. The method of claim 1, wherein the liquid is an adhesion promoter.

15. The method of claim 14, wherein the adhesion promoter is an aqueous solution comprising [Cr(H.sub.2O).sub.5(C.sub.4H.sub.3O.sub.4)](NO.sub.3).sub.2.

16. The method of claim 1, wherein the liquid is a heat-sealing primer.

Description

EXAMPLE

(1) In this example, the proportions are by mass, unless indicated otherwise.

(2) An adhesion promoter is applied to glass jars having an outer collar diameter of 54.4 mm and a rim width of 4.2 mm.

(3) The adhesion promoter is an aqueous solution of a complex of chromium(III) nitrate and fumaric acid [Cr(H.sub.2O).sub.5(O.sub.4H.sub.3O.sub.4)](NO.sub.3).sub.2, containing 0.13% of chromium(III) and 0.3% of fumaric acid, which is sold by Ardagh Glass Holmegaard A/S from Denmark under the registered trademark Volan.

(4) This solution is diluted where appropriate with demineralized/deionized water, its concentration being indicated as a proportion of chromium.

(5) Two coating rollers are used: a first roller with a surface composed of a denim, and a second which differs from the first only in that the denim is coated with a tubular knit of 21 rib construction, composed of a para-aramid yarn with a metric number of 1/040 Nm (i.e., 40 m/g).

(6) FIG. 1 shows the dry amounts of the adhesion promoter applied to the rim of the jars, at the front of the coating (the part of the rim making contact with the roller first), labeled AV; at the back of the coating, labeled AR, and on the right and left sides of the rim, labeled D and G. These dry amounts are expressed in g/mm.sup.2.

(7) The roller coated with denim is labeled roller 1; the roller coated with tubular knit is labeled roller 2.

(8) In FIG. 1 it is seen that coating with the noninventive roller 1 applies a much greater amount at the back of the coating, whereas the thickness of the coating applied with the inventive roller is uniform over the entire circumference of the rim.

(9) It is also noted that, apart from the rear part of the rim, the noninventive roller, from a solution with 0.043% of chromium, applies a dry amount which is equivalent to that applied with the inventive roller from a solution containing 0.13% of chromium. However, these figures do not predict a better outcome in terms of the amount of adhesion promoter consumed in favor of the noninventive roller, since evaluating such an outcome requires other, dynamic measurements.

(10) On the other hand, it is indeed verified that the method of the invention is notable, as already stated, for the uniformity of thickness of the resulting coating. This thickness can easily be regulated through the selection of the concentration of the solution applied.