GB2237000A

GB2237000A - Container Wall Construction

Info

Publication number: GB2237000A
Application number: GB9024046A
Authority: GB
Inventors: Steen Vesborg
Original assignee: Colgate Palmolive Co
Current assignee: Colgate Palmolive Co
Priority date: 1986-10-21
Filing date: 1987-10-20
Publication date: 1991-04-24
Anticipated expiration: 2007-10-20
Also published as: GB9024046D0; GB2237000B

Abstract

A container (10), in particular a disposable plastic bottle, comprises a hyperboloidic surface (34), and a closure at one end. The hyperboloidic surface ensures that the wall does not dimple when the interior of the container is subject to low pressure. The side wall 16 may carry a printed panel 14. <IMAGE>

Description

A CONTAINER, A BLANK FOR A CONTAINER AND A METHOD FOR ITS PRODUCTION The present invention relates to a container with printed information and in particular to a disposable plastic bottle. The invention further relates to a method of manufacturing a container blank and to a container blank for forming the container.

Various different containers are known in which information is printed on a cylindrical, conical or planar surface in order to permit mass production of the container with printed information.

It is an object of the present invention to provide a container of the above type, which is suitable for mass production, which has an agreeable external appearance and which is pleasant to handle.

According to one aspect of the invention, there is provided a container such as a disposable plastics bottle comprising a hyperboloidic surface or a hyperboloidic-like surface, on which information has been printed by means of a printing technique using line contact between the surface to be printed on and the print transferring element. As a result a container is obtained with an agreeable external appearance, and which is pleasant to handle and which is at the same time particularly suited for mass production.

According to another aspect of the invention, there is provided a method of printing on a hyperboloidic surface or a hyperboloidic-like surface of a container blank by means of a serigraphy-machine including a doctor blade in contact with a silk screen, in,which the doctor blade is moved relative to the screen, the side of the screen positioned opposite the doctor blade is maintained in constant line contact with the surface of the container blank to be printed on during relative movement between the blade and the screen, the container blank being moved synchronously with the doctor blade, and in which the doctor blade and consequently its line of contact with the screen are arranged as generatrix for the hyperboloidic surface or the hyperboloidic-like surface to be printed on in such a manner that the print producing part of the screen remains in line contact with the surface along a generatrix.

This implies that it is possible very quickly and rationally to apply print to hyperboloidid surfaces or hyperboloidic-like surfaces with a rectilinear generatrix, whereby the degree of freedom with respect to the construction of the container is increased considerably.

The screen may according to the invention stand still while the doctor blade and the container blank are moved synchronously in relation to each other.

Consequently, the method becomes very simple and easily practicable.

According to another aspect of the invention, there is provided a plastics.container blank for manufacturing the container according to the invention, in particular a plastic bottle for liquid, powdered or paste-like cleaning materials or. detergents, the container blank including a closable opening, and in which a horizontal section through the wall of the container blank in its upright position describes a convex curve, preferably substantially an ellipse or a circle, and in which at least portions of the wall of the container blank describe one or several hyperboloidic surfaces or hyperboloidic-like surfaces.

Such a container will, when containing an oxygen absorbing medium, not be visibly deformed when the medium absorbs the oxygen and a partial vacuum arises inside the container. This is particularly due to the fact that a relative rotation or bending, caused by the partial vacuum, between the upper and lower parts of the container blank, about the longitudinal axis of the container blank will not be visible provided part of the wall of the container blank is a hyperboloidic surface and or a hyperboloidic-like surface. This is opposed to what would be the case is the wall of the container blank was e.g. a cylindrical surface, which would dent if a partial vacuum should arise in the container blank.

Preferably, the wall of the container blank comprises a number of pairs of hyperboloidic surfaces or hyperboloidic-like surfaces which are mutually symmetrical about symmetry planes along the longitudinal axis of the container blank.

In a preferred embodIment of the container according to the invention the container has a substantIallyelliptic cross-section, and the wall of the container blank comprises two pairs of hyperboloidic surfaces mutually symmetrical about two mutually perpendicular symmetry planes. A container blank is consequently obtained with an agreeable external appearance and which is pleasant and easy to handle.

Preferably, the waist-curve of the hyperboloidic surfaces or the hyperboloidic-like surfaces are contained in the wall of the container blank.

Preferably, the dimensions across the blank at the two symmetry planes are the same at the shoulder as they are at the base.

The invention may be carried into practice in various ways and one embodiment will now be described by way of example with reference to the accompanying drawings in which: Figure 1 is a side view of a container according to the invention with printed information; Figure 2 is a top view of the container of Figure 1; Figure 3 is a transverse cross-section of the container along the line III-III of Figure 2; and Figure 4 is a schematic view of a method according to the invention for applying print to a hyperboloidic surface.

Figures 1 and 2 are a side view and a top view, respectively, of a preferred embodiment of a container 10 according to the invention with printed information.

The areas 12, 14 of the container 10, on which information has been printed, are shown in broken lines. The container 10 comprises a body 16 which at the top passes into a shoulder 18 and at the bottom into a base 20. The shoulder 18 is substantially partconical, is inclined relative to the longitudinal axis 22 of the container and passes at the top into a neck 24 provided with a closable opening. The base 20 extends from the body 16 in a slightly conical downward direction to form the.support surface 26 of the container 10.

As shown in Figure 3, the body 16 has a substantially elliptical cross-section made up of two pairs of hyperboloidic surfaces 28, 30 and 32, 34, respectively, which are mutually symmetrical about two mutually perpendicular symmetry planes. The areas 12, 14 with printed information form part of the hyperboloidic surfaces 32, 34. As can be seen from Figures 1 and 2, the greatest dimensions lmaXt bmax of the container along the two symmetry planes of the body 16 are the same at the shoulder 18 and at the base 20, and the body 16 has its smallest dimensions 1max' bmax at the waist-curves, (Figure 3) for the two pairs of symmetrical hyperboloidic surfaces 28, 30 and 32, 34, respectively. This means that the container will stand steadily and stably when packed in e.g. a cardboard box.

The container blank may be manufactured by blow moulding and is particularly suited for stretch blow moulding.

The container blank is preferably made from a plastics material, such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyethylene terephthalateglycol (PETG), polyvinyl chloride (PVC), acrylonitrile (AN) and copolymers thereof. These materials may also contain a reinforcing material such as glass fibre.

As a result of the use of hyperboloidic surfaces 28,30; 32, 34 for the formation of the body 16, there is no visible deformation of the container blank 10, when a partial vacuum arises therein. A partial vacuum can occur in a container blank when the container blank contains an oxygen absorbing medium, e.g. a medium containing aldehydes or unsaturated fatty acids, and the container blank is not filled completely during filling. The medium will then absorb the oxygen after some time. Due to the partial vacuum formed, the upper part of the container blank will tend to bend or rotate relative to the lower part of the container blank.

This will result in a dent in the body if the container does not - as in the present invention - consist of hyperboloidic surfaces 28, 30 and 32, 34 respectively, or hyperboloidic-like surfaces.

The method for applying print, preferably serigraphy, to a hyperboloidic surface or a hyperboloidic-like surface of a container blank is schematically illustrated in Figure 4. This figure shows a hyperboloidic surface 40, to which serigraphy should be applied. In serigraphy a doctor blade 42 is used in contact with a planar, flexible silk screen 41 (illustrated with a dot-and-dash line). The doctor blade 42 moves relative to the silk screen 41 and thus presses ink through the masks of the silk screen 41 and onto the surface to be printed i.e. in the present case the hyperboloidic surface 40. The surface 40 moves synchronously in relation to the movement of the doctor blade in such a manner that there is constant line contact between the surface to be printed on and the silk screen 41, and between the silk screen 41 and the doctor blade 42, respectively.

In the method according to the invention the doctor blade 42 and consequently its line of contact with the silk screen 41 arranged as the generatrix for the hyperboloidic surface 40 to be printed on, whereafter the doctor blade 42 moves rectilinearly across the silk screen 41, which stands still, and simultaneously the hyperboloidic surface is partly rotated and partly moved translatively synchronously with the movement of the doctor blade 42. Thus, the print causing part of the silk screen 41 remains in line contact with the surface along a generatrix to the hyperboloidic surface 40.

It is thus possible by means of the method according to the invention to apply print to an arbitrarily formed surface which can be formed by propagating a rectilinear generatrix along any planoconvex directrix, the generatrix generally not being surface normal compared to the plane of the directrix. The hyperboloid is a special example thereof, as the curved guide is here an ellipse or in connection with a rotary hyperboloid a circle.

Claims

1. A container which includes a hyperboloidic surface or a hyperboloidic-like surface, on which information has been printed by means of a printing technique using line contact between the surface to be printed on and the print transferring element.

2. A method of printing on a hyperboloidic surface or a hyperboloidic-like surface of a container blank by means of a serigraphy-machine including a doctor blade in contact with a silk screen, in which the doctor blade is moved relative to the screen, the side of the screen positioned opposite the doctor blade is maintained in constant line contact with the surface of the container blank to be printed on during relative movement between the blade and the screen, the container blank being moved synchronously with the doctor blade, and in which the doctor blade and consequently its line of contact with the screen are arranged as generatrix for the hyperboloidic surface or the hyperboloidic-like surface to be printed on, whereafter the doctor blade and the screen are moved relative to each other and relative to the surface to be printed on in such a manner that the print producing part of the screen remains in line contact with the surface along a generatrix.

3. A method as claimed in Claim 2, in which the screen stands still while the doctor blade and the container blank are moved synchronously in relation to each other.

4. A method of printing on a hyperboloidic or a hyperboloidic-like surface substantially as herein specifically described with reference to and as shown in Figure 4 of the accompanying drawings.

5. A container including a closable opening, and in which a horizontal section through its wall when in an upright position describes a convex curve and in which at least portions of the wall of the container blank describe one or several hyperboloidic surfaces or hyperboloidic-like surfaces.

6. A container printed with information, constructed and arranged substantially as herein specifically described with reference to and as shown in Figures 1 to 3 of the accompanying drawings.

6. A container as claimed in Claim 5 in which the wall of the container blank comprises a number of pairs of hyperboloidic surfaces or hyperboloidic-like surfaces which are mutually symmetrical about symmetry planes along the longitudinal axis of the container blank.

7. A container blank as claimed in Claim 6 having a substantially elliptical cross-section and in which the wall of the container blank comprises two pairs of hyperboloidic surfaces or hyperboloidic-like surfaces which are mutually symmetrical about two mutually perpendicular symmetry planes.

8. A container blank as claimed in any of Claims 5 to 7 in which the waist-curve of the hyperboloidic surfaces or the hyperboloidic-like surfaces are contained in the wall of the container blank.

9. A container blank as claimed in any of Claims 5 to 8.in which the dimensions across the blank at the two symmetry planes are the same at the shoulder as they are at the base.

10. A container printed with information, constructed and arranged substantially as herein specifically described with reference to and as shown in Figures 1 to 3 of the accompanying drawings.

Amendments to the claims have been filed as follows

1. A container including a closable opening, and in which a horizontal section through its wall when in an upright position describes a convex curve and in which at least portions of the wall of the container describe one or several hyperboloidic surfaces or hyperboloidic-like surfaces.

2. . A container as claimed in Claim 1 in which the wall of the container comprises a number of pairs of hyperboloidic surfaces or hyperboloidic-like surfaces which are mutually symmetrical about symmetry planes along the longitudinal axis of the container blank.

3. A container as claimed in Claim 2 having a substantially elliptical cross-section and in which the wall of the container comprises two pairs of hyperboloidic surfaces or hyperboloidic-like surfaces which are mutually symmetrical about two mutually perpendicular symmetry planes.

4. A container as claimed in any of Claims 1 to 3 in which the waist-curve of the hyperboloidic surfaces or the hyperboloidic-like surfaces are contained in the wall of the container.

5. A container as claimed in any of Claims 1 to 4 in which the dimensions across the container at the two symmetry planes are' the same at the shoulder as they are at the base.