The invention concerns a dispenser for simultaneously delivering two compositions from separate chambers.

Not all chemical ingredients are mutually compatible. Separation may be required because of chemical reactivity or physical incompatibility during storage. Certain health and beauty aids, cleaning compositions and dental formulas may be benefited by packaging that separates respective components of these products. Of particular concern have been dental products which require simultaneous delivery of mutually reactive sodium bicarbonate and hydrogen peroxide.

The art has described a number of packages that separate reactive components by placing their compositions in different chambers. Only at the point of use are these compositions combined. For instance, U.S. Patent 5,020,694 (Pettengill) and U.S. Patent 5,038,963 (Pettengill et al) describe rigid piston-type multi-cavity dispensing containers for simultaneous co-extrusion of two or more flowable materials in a predetermined proportion. These rigid containers have the advantage of relatively good control over the co-extrusion process. On the other hand, a considerable amount of plastic is involved in their construction. For environmental reasons, packaging with less plastic is sought.

Another suggestion in the art has been to utilise side-by- side collapsible tubes for toothpaste compositions. Representative of this technology is U.S. Patent 4,487,757 (Kiozpeoplou) , U.S. Patent 4,687,663 (Schaeffer) , and U.S. Patent 4,964,539 (Mueller). Each of these disclosures describes a pair of tubes that have been crimped at an end distant from the product dispensing cap end. Actual attempts to crimp the ends of similar tube designs have

resulted in improper seals. Not only were the result crimps difficult to form, but leakage was also noted in several instances.

Accordingly, it is an object of the present invention to provide a dual chamber dispenser utilising less plastic than rigid packaging while still providing good control over co- extrusion of the components.

Another object of the present invention is to provide a dual chamber dispenser utilising a pair of flexible tubes who ends can readily be crimped and whose crimp provides an adequate seal.

Other objects, features and advantages of this invention will become more apparent upon reference to the following detailed description and drawings illustrating a preferred embodiment thereof.

The object of the present invention may be achieved through use of a pair of elongated hollow tubes each of whose cross- section shape changes gradually from a D-shape at a dispensing end to a round or oval shape at a sealing end. Each of the tubes at the dispensing end are D-shaped so that they can readily adjoin one another along a straight surface. On the other hand, at the sealing end distant from the dispensing opening, each tube has gradually transitioned into a round or oval shape to allow for ready crimping in a seal-effective manner.

Thus, according to a first aspect of the invention, there is provided a dual-chamber dispenser including: a cap having a dispensing base and a cover, the cover being hingedly attached to the base; and

shaped hollow seal members each configured as a sector of a circle.

Preferably a hinge is provided to attach the cover to the base. The hinge may conveniently be bisected by a plane separating one of the hollow tubes from the other.

On the dispensing base is an upper and lower surface. A circular spout with an opening bisected by a divider wall can project upwards from the upper surface. A base skirt can project away from the spout and surrounds the lower surface of the base. A pair of hollow cylindrical nozzles may rise from the base lower surface. Each of the nozzles communicates separately with a respective channel leading into the divided spout. Furthermore, each of the nozzles ideally fits snugly into a respective one of the exit orifices of the hollow tubes. Cross-sectional dimensions of the respective nozzles and/or exit orifices for each pair may be of different opening size to allow adjustment for control of component flow, depending upon the flow characteristic of each component.

A series of projections spaced along a lower edge of the base skirt are conveniently arranged to engage the undercut recess of each of the hollow tubes. In a second embodiment, the coupling device employs a pair of semicircular projections protruding from the lower surface of the base downwardly with each partially surrounding a respective nozzle. Along a lower edge of each semicircular projection is an inwardly directed ledge engageable with a D-shaped undercut recess surrounding each exit orifice of the respective hollow tube.

The round or oval ends of the hollow tubes, subsequent to filling with product, are crimped together by a heat sealing machine. Such machines are well-known in the art.

The invention will now be further described by way of example only with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of the dispenser with open cover;

Fig. 2 is a front elevational view of the dispenser with closed cover;

Fig. 3 is a rear elevational view of the dispenser with closed cover;

Fig. 4 is a perspective view of the pair of elongated hollow tubes positioned adjacent one another but without cap;

Fig. 5 is an elevational view of a single one of the elongated hollow tubes without cap and prior to being crimped;

Fig. 6 is a cross-sectional view taken along line VI VI of Fig. 5;

Fig. 7 is a cross-sectional view taken along line VII VII Of Fig. 5;

Fig. 8 is a perspective view of the dispensing base portion of the cap;

Fig. 9 is a bottom view of a second embodiment of the dispensing base portion of the cap;

Fig. 10 is a perspective view of the second embodiment of the dispensing base portion of the cap; and

Fig. 11 is an elevational view of a second embodiment of a single one of the elongated hollow tubes without cap and prior to being crimped.

The dual-chamber dispenser of the present invention is best viewed in Figs. 1-3 which illustrate a cap 2 including a dispensing base 4 and a cover 6. Hinge 8 flexibly attaches base 4 to cover 6. A pair of elongated hollow tubes 10 are joined to an underside of the dispensing base 4. An upper end 12 of each hollow tube 10 has an exit orifice 14. Each hollow tube 10 employs a coupling mechanism 16 for joining same to underside 18 of the dispensing base 4. Upper end 12 is D-shaped in cross-section as shown in Fig. 6. Lower end 20 of hollow tube 10 is either round or oval in cross- section. A crimp 22 seals together each of the lower ends of tubes 10.

Fig. 3 illustrates hinge 8 as being bisected by a plane X-X. This plan demarcates the planar separation between each of the hollow tubes 10.

Fig. 4 shows that upper end 12 of hollow tube 10 is closed by a D-shaped surface 24 defined by ends of a curvilinear edge 26 intersecting a straight edge 28. Coupling mechanism 16 is in the form of an undercut recess 30 symmetrically traced below the D-shaped surface 24 all along the curvilinear edge 26. Exit orifice 14 is positioned on surface 24 at a point adjacent straight edge 28. Figs 2-3 illustrate cover 6 as including an outer upper flat surface 32 with a circumference no smaller than a largest circumference around both of the hollow tubes 10. In a direction away from the upper flat surface 32 is a skirt 34 which surrounds inner flat surface 36 of cover 6. A seal mechanism 38 is centred on the inner flat surface 36. Included within the seal mechanism is a circular outer wall 40 protruding away from the inner flat

surface 36 and a pair of D-shaped hollow seal members 42 each configured as a sector of a circle.

Fig. 5 illustrates a single hollow tube 10 prior to being joined with a second of the hollow tubes and cap, and prior to being crimped. Fig. 7 illustrates the round or oval shape of tube 10 near to its lower end 20.

Fig. 8 provides a view of the dispensing base 4 which includes an upper surface 44 and a lower surface 46. A circular spout 48 projects upward from upper surface 44 and is provided with an opening 50 that bisected by a divider wall 52. A base skirt 54 projects away from spout 48 and surrounds the lower surface 46. Projecting downward from lower surface 46 are a pair of hollow cylindrical nozzles 56. Each of nozzles 56 communicate separately with a respective channel 58 leading into the divided spout 48.

Hollow tubes 10 are fastened in a dual manner to cap 2. Firstly, a set of projections 60 are symmetrically positioned along a lower edge 62 of base skirt 54. These projections 60 engage recess 30 of tubes 10 in a fastening manner. Secondly, each of nozzles 56 tightly insert into a respective exit orifice 14 to further secure hollow tubes 10.

Fig 9 to 11 illustrate a second embodiment of the coupling arrangement for securing the hollow tube 10 to cap 2. In this embodiment, a pair of semicircular projections 64 extend from lower surface 46 of dispensing base 4 in a downward direction. Each projection 64 partially surrounds a respective nozzle 56. An inwardly directed ledge 66 is formed along a lower edge 68 of each projection 64. Ledge 66 is engageable with a D-shaped undercut recess 70 that surrounds each exit orifice 14 of the respective hollow tube 10.

The foregoing description illustrates only selected embodiments of the present invention, variations and modifications all being within the spirit and purview of this invention.