WO2009128718A1

WO2009128718A1 - Container filled with an adhesive or sealant

Info

Publication number: WO2009128718A1
Application number: PCT/NL2009/050202
Authority: WO
Inventors: Boudewijn Rooze
Original assignee: Bison International B.V.
Priority date: 2008-04-15
Filing date: 2009-04-15
Publication date: 2009-10-22
Also published as: NL2001484C2; NL2002750A1

Abstract

The invention relates to a container for an adhesive or sealant. The container has the feature that the container is filled with an adhesive or sealant on the basis of chloroprene rubber and/of styrene butadiene rubber and comprising a solvent or a mixture of at least two solvents; and at least a predominant part of the inner surfaces of the container that are in contact with adhesive or sealant consists of a material compatible with the solvent or the mixture of solvents and forming a diffusion barrier therefor, which material comprises at least a predominant proportion of PET (polyethylene terephthalate).

Description

CONTAINER FILLED WITH AN ADHESIVE OR SEALANT

The invention relates to a container for an adhesive or sealant. Such a container is for instance known from the European patent application EP-A-I 925 569.

Known from this reference is a container which is intended to contain a pasty mass, for instance an adhesive or sealant. According to this publication the walls of the container consist wholly of PET (polyethylene terephthalate) . In this publication no specification is given of the composition of the pasty mass to be received in the container, or of the solvents applied therein.

There are specific solvents, applied in practice by applicant for adhesives and sealants (sealing materials), which are not compatible with the plastic materials usually applied for containers therefor or which tend to evaporate therethrough due to diffusion. Use is therefore sometimes made of polyamide and of aluminium and other metals as barrier layer. A drawback of polyamide is the relatively high cost price. Aluminium and other metals have the drawback that they have no "memory", whereby dents can easily form in the material and the material does not return to its original shape. In addition, both polyamide and metals have the drawback that there are restrictions to the possible shapes a packaging can have. It is for instance very difficult, if not impossible, to make a bottle from polyamide. In the choice of this plastic use is therefore often made of a co-extrudate of PE with an inner layer of PA. This entails higher costs than the use of a single material.

For solvent-containing chloroprene rubber and styrene butadiene rubber adhesives use is made of one or more solvents, the composition of which is chosen such that the rubber falls within the solubility range of this solvent or mixture of solvents. PET does not display barrier properties for all individually applied solvents, although many applied mixtures can be held in PET. In other words, the mixture of solvents behaves as if it were a new solvent which is compatible with PET.

The invention is based on the insight that adhesives on the basis of chloroprene rubbers and/or styrene butadiene rubbers and the associated solvents have an excellent compatibility with PET, while PET also forms an excellent diffusion barrier thereto and prevents undesired substances entering the container, and therefore need only be present in the form of a cover layer on the surfaces in contact with the adhesive or sealant.

For the present specification and claims a compatible material is understood to mean a material which has good barrier properties and does not degrade, in particular preserves its form-retention, despite the influence of various factors, in particular the solvent or the mixture of solvents. The barrier properties must be such that escape of a solvent is effectively blocked, while undesired substances are also prevented from entering the container from outside. It is an object of the invention to embody a container such that the desired compatibility between the solvent-containing mass and the container is ensured, while the costs of the container are nevertheless greatly limited.

It is also an object of the invention to ensure, at low cost, that the shelf life of a filled container is lengthened substantially relative to the known filled containers.

Is also an object of the invention to provide a container which allows a high degree of freedom in the choice of the shape of a container. In respect of the above, the invention relates to a combination of this compatible barrier material with an adhesive or sealant on the basis of chloroprene rubber and/or styrene butadiene rubber and solvents which are applied herein. In this respect a container according to the invention has the feature that the container is filled with an adhesive or sealant on the basis of chloroprene rubber and/of styrene butadiene rubber and comprising a solvent or a mixture of at least two solvents; and at least a predominant part of the inner surfaces of the container that are in contact with adhesive or sealant consists of a material compatible with the solvent or the mixture of solvents and forming a diffusion barrier therefor, which material comprises at least a predominant proportion of PET (polyethylene terephthalate) .

In a specific embodiment the container can have the special feature that the predominant part of the inner surfaces is formed by the whole of the inner surfaces. In yet another embodiment the container has the feature that the material also comprises PEN.

According to yet another aspect of the invention, the container has the special feature that the whole container consists of said material. The container can be manufactured by means of extrusion. This is a known, reliable and inexpensive method of manufacturing prismatic products, i.e. products which have the same cross-sectional form at any axial position. A container according to the invention can further have the special feature that the container is manufactured by blow moulding, injection blow moulding or injection moulding.

In some circumstances it may be desirable for the container to be translucent, for instance transparent. According to yet another aspect of the invention, the invention has the feature that the material is arranged as a cover layer on another material, for instance a plastic or cardboard.

According to yet another aspect of the invention, the container has the special feature that the container is a squeezable tube or bottle.

According to another further aspect of the invention, the container has the special feature that the container has a prismatic, in particular cylindrical inner shape and comprises a piston which can be operated from outside and co-acts sealingly and slidably with the prismatic inner surface for pressing mass outward via a dispensing opening when the piston is pushed, wherein at least a predominant part of the inner surfaces of the piston that are in contact with adhesive or sealant consist of a material compatible with the solvent and forming a diffusion barrier therefor, which material comprises at least a predominant proportion of PET (polyethylene terephthalate) , optionally in combination with a certain proportion of PEN.

A cylindrical form will generally be preferred for a prismatic container/dispenser. As is known, this deforms to only negligible extent when pressure is exerted, for instance when a pasty mass of high viscosity is pressed out of the container under relatively high pressure by displacing the piston.

According to a determined aspect of the invention, the container can have the special feature that the whole piston consists of PET, optionally in combination with a certain proportion of PEN.

A container according to the invention can further be embodied such that the material is present in the form of a cover layer on a second material. In this latter embodiment the relevant wall of the container or the relevant wall part comprises two or more layers, of which the inner side coming into contact with solvent-containing mass consists of PET, optionally in combination with a certain proportion of PEN. Such a structure consisting of multiple layers can for instance be manufactured by means of co-extrusion.

Alternatively or in combination therewith, the container can have the special feature that the container is manufactured by in-mould labelling. According to a further aspect of the invention, the container can have the feature that the container comprises a dispensing opening which is covered by a removable cap. The use of such a cap has the advantage that a container which has not been fully emptied can be resealed, such that mass exposed to the air does not harden as a result of the evaporation of solvent.

The above described embodiment can preferably be embodied such that the container has a screw thread in the vicinity of the dispensing opening which co-acts with a screw thread present on the cap.

The desired wall thickness of a container depends on, among other factors, the mechanical properties of the material used.

The dimensions of a container with a piston can for instance amount to: length: 215 mm, outer diameter about 48 mm. The thickness of the wall can lie in the range of 0.3 - 2.5 mm. In the case of a reclosable dispensing opening a cap or cover can be provided with a tamper-evident seal. When seeing an intact seal the purchaser can be sure that the container has not yet been opened.

Additives which can have a positive effect on, among other properties, the heat resistance of the container can be added to the material of at least part of the inner surfaces of the container, at least a predominant part of which material consists of PET. It is hereby possible for the container to preserve its form-retention, even in the case of prolonged exposure to high temperatures.

Other grades of PET can also be used to realize the same objective.

Attention is drawn to the fact that the invention is not limited to a squeezable tube or a generally tubular container provided with a displacing means, for instance a piston, but that the invention can also be applied with a container which is embodied as a cup, bucket or bottle. Such a container also has a dispensing opening, in particular a mouth, which is covered by a cover prior to first opening. Such a cover is known in combination with a container in many embodiments and can preferably also be provided with a tamper-evident seal. At least the inner surface of such a cover will preferably be embodied, as the container itself, such that at least a component of the material of the inner surface thereof consists of PET, optionally in combination with a certain proportion of PEN.

Claims

1. Container for an adhesive or sealant, characterized in that the container is filled with an adhesive or sealant on the basis of chloroprene rubber and/of styrene butadiene rubber and comprising a solvent or a mixture of at least two solvents; and at least a predominant part of the inner surfaces of the container that are in contact with adhesive or sealant consists of a material compatible with the solvent or the mixture of solvents and forming a diffusion barrier therefor, which material comprises at least a predominant proportion of PET (polyethylene terephthalate) .

2. Container as claimed in claim 1, wherein the predominant part of the inner surfaces is formed by the whole of the inner surfaces.

3. Container as claimed in either of the foregoing claims, wherein the material also comprises PEN polyethylene-2, 6-naphthalate.

4. Container as claimed in any of the foregoing claims, wherein the whole container consists of said material.