DISPENSING CONTAINER HAVING IMPROVED TORQUE RESPONSE

AND CLOSURE SEALING

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a container for dispensing a product. The present invention also relates to a tubular dispensing container of small diameter. The present invention further relates to a dispensing container having improved torque '^retention and response and closure sealing.

2. Description of the Related Art Dispensing containers are employed commercially to dispense products for a variety of consumer and industrial applications. Such dispensing containers typically have a head, a body or receptacle, and a closure. Particularly useful are tubular dispensing containers, which have a body or receptacle in the form of a tube. Tubular dispensing container of small head and tube diameter, i.e., about 10 millimeters (mm) to about 25 mm, have been useful in pharmaceutical and cosmetic applications.

Industry has avoided use of screw-type tube dispensing containers of small diameter due to handling and use problems. As the closure is screwed onto the neck, excessive torque is generated when the leading edge of the closure contacts the shoulder. The excessive torque forces the thread-bearing surface of the closure, usually a skirt or wall of the closure, outward due to insufficient rigidity of the skirt or wall. The outward force can diminish the ability to completely screw on

the closure and the ultimate integrity of seal between the closure and the neck.

It would be desirable to have a dispensing container having improved torque retention and response and closure sealing. It would also be desirable to have a tubular dispensing container of small diameter having such improved torque retention and response and closure sealing.

SUMMARY OF THE INVENTION

According to the present invention, there is a dispensing container. The dispensing container has a head, a body, and a closure. The head has a neck and a shoulder. The neck also has a bore extending longitudinally therethrough. The neck defines one or more external threads. The head has an indentation extending therein and circumferentially therearound proximal to the junction of the neck and the shoulder. The indentation is bounded by a tapered surface tapering outward with respect to the neck towards a top surface of the shoulder. The body is connected to the shoulder. The body has a chamber therein adapted to retain a product. The bore is in communication with the chamber. The closure defines one or more internal threads therein. The one or more internal threads are intermated with the one or more external threads. The closure has a skirt having a leading edge. The indentation in the head receives the leading edge. The leading edge contacts the tapered surface. The closure is openable and reclosable with respect to the head. The head and the closure are adapted such that the leading edge returns to contact with the tapered surface when the closure is re-closed.

DESCRIPTION OF THE FIGURES

Fig. 1 is a perspective view of a dispensing container according to the present invention.

Fig. 2 is a perspective view of the dispensing container of Fig. 1 without the closure.

Fig. 3 is an enlarged, cross-sectional view of the dispensing container of Fig. 2 along line 3-3.

Fig. 4 is an enlarged, close-up view of a portion of the cross-sectional view of Fig. 3 at Inset 4.

Fig. 5 is an enlarged, cross-sectional view of the dispensing container of Fig. 1 along line 5-5.

Fig. 6 is an enlarged, close-up view of a portion of the cross-sectional view of Fig. 5 at Inset 6.

DETAILED DESCRIPTION OF THE INVENTION The dispensing tube of the present invention provides improved torque retention and response and closure sealing. The dispensing tube has a tapered surface within an indentation in the head that is adapted to receive and contact the leading edge of a closure. The tapered surface diminishes excessive torque generated when the closure is screwed onto the neck of the head.

The tapered surface is present within an indentation that extends into the head proximal to the junction of the neck and the shoulder and that extends circumferentially around the neck. The tapered surface tapers or slopes outward with respect to the neck (away from the neck) towards a top surface of the shoulder.

The taper or slope of the tapered surface enables the leading edge of the skirt of the closure to be easily received yet simultaneously be contained, constrained, or blocked as the closure is screwed on to the neck and head. Since the tapered edge is tapered inward toward the neck, the leading edge is guided and constrained inward the farther down the closure is screwed.

The tapered surface has a positive slope with respect to the longitudinal extension of the neck. The tapered surface is inclined at an angle of about 20° to about 70° and preferably about 30° to about 45° with respect to an imaginary line perpendicular to the longitudinal extension of the neck. The tapered surface may be substantially flat (planar) or curved. Flat (planar) is preferred.

Although the present invention is useful with dispensing containers of any size or diameter, it is particularly useful with dispensing containers having small head diameters. In the instance of tube dispensing containers, such small diameters typically range from about 10 mm to about 25 mm.

The body or receptacle of the dispensing container may take any form or shape known in the art, such as a bottle or a tube. α preferred body or receptacle is a tube.

Plastic tube dispensing containers may be produced by any method known in the art, such as extrusion or lamination. In extrusion, plastic tubes are extruded continuously and cut into discrete lengths to form tube lengths or sleeves. Heads are then heat welded or adhered to the tube lengths to form dispensing containers. Closures, such as a caps or tops, are applied to the heads to form packages. The open ends of packages are typically filled with product to be dispensed and then sealed by heat or mechanical means. A preferred means of sealing may be carried out by overlapping the open ends and following with heat sealing. In lamination, sheets of plastic material are rolled into tubes and sealed along the sheet edges to form continuous tubes. The continuous tubes are cut into discrete tube lengths and further processed in the same manner as described above for extruded dispensing containers.

The closure and head may be manufactured according to any method known in the art such as injection molding, compression molding or stamping with a plastic material. Injection molding is preferred.

The dispensing container may be manufactured from any plastic material known in the art. Representative plastic materials include ethylene polymers, propylene polymers, polyesters, and polyamides . Useful ethylene polymers include low density polyethylene, medium density polyethylene, high density polyethylene and linear low density polyethylene. A

useful propylene polymer is polypropylene. Useful polyesters include polyethylene terephthalate. Preferred plastic materials are low density polyethylene and polypropylene. Different parts of the package may be manufactured from the same or different materials. A preferred plastic material for tube body walls is low density polyethylene. Preferred plastic materials for the head and the closure are high density polyethylene and polypropylene .

A preferred embodiment of a dispensing container is shown in Fig. 1 and is generally referenced by the numeral 10. Dispensing container 10 has a head 12, a body 30, and a closure 36. As shown in Fig. 2, head 12 has a neck 14 and a shoulder 16. Neck 14 has a bore 18 extending longitudinally through it. Neck 14 defines one or more external threads 20. As shown in Fig. 3, body 30 is connected to shoulder 16. Body 30 has a chamber 32 therein adapted to retain a product (not shown) . Bore 18 is in communication with chamber 32. As shown in Fig.

5, closure 36 has a top panel 38 and an inner skirt 42 and an outer skirt 44 appending therefrom. Inner skirt 42 has a leading edge 46. Closure 36 defines one or more internal threads 48. The one or more internal threads 48 mates with the one or more external threads 20 of neck 14. Figure 5 shows claws 39 and 41, which help maintain a tight seal and prevent product (not shown) from leaking out of closure 36. Other types of seals, such as plug seals (not shown), are also possible.

Head 12 has an indentation 22 extending therein and circumferentially therearound proximal to the junction of neck 14 and shoulder 16 as shown in Fig. 3. As shown in Figs. 4 and

6, indentation 22 is partially bounded by an inner surface 24

that is generally directional with respect to neck 14 and extends circumferentially around neck 14. Indentation 22 is also partially bounded by a bottom surface 26 that generally perpendicularly intersects inner surface 24 and extends outward with respect to neck 14. Bottom surface 26 intersects tapered surface 28. Tapered surface 28 tapers outward with respect to neck 14 towards top surface 29 of shoulder 16. Tapered surface 28 is substantially flat or planar. Tapered surface 28 is inclined at an angle of 30° (θ = 30°) with respect to an imaginary line 27 perpendicular to the longitudinal extension of the neck. Indentation 22 receives leading edge 46 as closure 36 is screwed onto head 12. As leading edge 46 contacts tapered surface 28, the outward force generated by the interaction of internal thread (s) 48 and external thread (s) 20 when closure 36 is screwed on neck 14 is counteracted and effectively diminished or constrained.

Closure 36 is openable and reclosable with respect to head 12. Head 12 and closure 36 are adapted such that leading edge 46 returns to contact with tapered surface 28 when closure 36 is re-closed.

It should be understood that the foregoing description is only illustrative of the present invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.