Container head with drip-less seal and method for producing the same

Abstract

The present invention is a container head containing a resilient annular sealing ring projecting from the surface plane of the shoulder of the container head. When the cap is seated on the container head, the resilient annular sealing ring forms a secondary fluid-tight seal between the container head and cap.

Description

INTRODUCTION

This application claims the benefit of priority from U.S. provisional application Ser. No. 60/746,197, filed May 2, 2006, which is herein incorporated by reference in its entirety.

BACKGROUND OF THE INVENTION

Containers such as plastic tubes and bottles are used to dispense a number of different products from body creams, lotions, shampoos and conditioners, to pharmaceutical ointments and creams. In general, the consumer desires a clean, easy to dispense, package and product. Most conventional tube and bottle packages have threaded or snap-on caps that fit to a molded threaded or snap-on head. These designs all leave a small space between the cap and the container head which can get filled with water or dirt. Since many containers are being designed to stand on the cap and many of these products are used in the shower, water fills the cap and pours out during use. This is especially unsatisfactory to the user when the water is cold or soapy and has been standing in the cap for a period of time.

Caps have been designed to contain a flange on the outer lip of the cap so that when contacted with the head of the tube a seal is created (Zeller Plastik, a Crown Cork & Seal company). See, e.g., U.S. Pat. No. 6,578,744. The drawbacks to this design are that it does not accommodate a wide variety of caps or tube designs and because the flange is rigid, the flange cuts into the tube head in order to create a seal. This cutting action can create plastic stings and dust on the tube head, which are considered contaminants.

U.S. patent application Ser. No. 10/498,241 also discloses a beverage bottle with a flange on the outside diameter of the cap, which corresponds to the outside diameter of the bottle edge.

U.S. Pat. No. 6,637,966 teaches a cap and a resilient sealing ring that seals between a shoulder of the container and an annular lip of the cap to provide an ectoseal. However, the sealing ring is neither integral with the cap nor the container.

SUMMARY OF THE INVENTION

The present invention is a container head with a drip-less seal. The container head of the invention has integrated into the shoulder thereof an annular sealing ring, which forms a fluid-tight seal with the interior surface of a container cap. Containers and methods for producing the container of head of the invention are also provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of a molded container head 10 with annular sealing ring 12 extending beyond the plane of the container shoulder 14 and contacting the inner surface of cap 20.

FIG. 2 is a sectional view of a molded container head 10 with annular sealing ring 12 extending beyond the plane of the container shoulder 14 and contacting chamfer 22 at the leading edge of cap 20.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is a container head with a resilient sealing member and method for producing the same. The improved container head provides a fluid-tight seal which prevents external water or other foreign materials from accumulating under the cap, i.e., in the space between the cap and the container head. The resilient sealing member is an annular sealing ring molded with the container head which contacts the cap to form a secondary seal at the inner surface of the cap wall. Advantageously, the instant container head can be used in combination with any type of cap including, threaded or snap-on caps.

By way of illustration, FIG. 1 depicts the instant molded container head 10 with a resilient annular sealing ring 12 contiguously molded into shoulder 14 of container head 10. As used herein, contiguously molded is intended to mean that the molded container head 10 and resilient annular sealing ring 12 are molded from a single piece of material. Container head 10 is intended to encompass the narrowing portion of a container through which fluid from the container body is dispensed. As such, container head 10 encompasses shoulder 14, collar or neck 16, and opening (not shown) located at the top of the container for dispensing the product. Alternatively stated, container head 10 is the portion of the container located above the body 18 of the container.

According to the present invention, annular sealing ring 12 projects or extends away from the surface plane of the shoulder 14 so that when the lid or cap 20 is seated on the tube head 10, annular sealing ring 12 contacts the inner surface or wall of cap 20 (FIG. 1) or chamfer 22 at the leading edge of cap 20 (FIG. 2). In particular embodiments, annular sealing ring 12 is integrated (i.e., contiguous) with the shoulder 14 of the container. As such, annular sealing ring 12 and shoulder 14 are produced from a single piece of material to create a unitary one-piece construction. The purpose of annular sealing ring 12 is to deform against cap 20 thereby forming a seal between the contacting surface of the container head 10 and the cap 20. In particular embodiments, the container is a squeeze type tubular container that is made of a soft plastic that is desirably softer than the material from which the cap 20 is fabricated. As such, annular sealing ring 12 is resilient or flexible and when pressed against the contacting surface of cap 20, annular sealing ring 12 will deflect to some degree, forming in effect a secondary fluid-tight or drip-less seal between the cap 20 and the container head 10.

As used in the context of the present invention, a container is intended to include squeeze tubes, squeeze bags, and squeezable bottles used for packaging and dispensing non-solid products of the type which are capable of flowing. Non-solid products include fluid or fluidized materials, including liquids, pastes, powders, and the like, which are collectively and generically referred to herein as fluids. Squeeze tubes or bags and squeezable bottles are flexible packages made from plastic material (e.g., low or high density polyethylene, polypropylene, polyethylene terephthalate, polyvinyl chloride, softouch, dual layer, or coextruded plastics), elastic material (e.g., silicone, thermoplastic elastomer, natural rubber, or synthetic rubber such as isoprene), or combinations thereof with one open end and one closed end. In particular embodiments, the container is a squeeze tube or bag formed by sealing a filled tube at one end resulting in a package with a cylindrical, open end and a flattened, closed end (e.g., a toothpaste tube).

In accordance with the present invention, the annular sealing ring is molded into the container head during the process of producing the container head. Thus, the one-piece construction of the container head is produced by selecting a suitable material and compression molding, injection molding, or bi-injection molding (e.g., when employing a combination of materials) a container head with a thin resilient annular sealing ring extending away from the surface plane of the shoulder. As will be appreciated by the one of skill in the art, the material for the container head can be any moldable material selected for producing the instant container head and can be dependent upon several factors including the flow properties of the fluid being dispensed and whether the container head is contiguous with the body of the container, an integral part of the container cap or lid, or produced as a separate component and welded to the container body. Desirably, the material selected for producing the container head is resilient and flexible, retaining its physical and/or chemical characteristics in response to ambient changes such as temperature fluctuations, repeated use, or exposure to active ingredients in the product. However, because the container material is composed of the same material as the annular sealing ring, it may be necessary to respectively select a more rigid container cap material or container body material suitable to stabilize the flexible material required of the annular sealing ring. Advantageously, the flexible nature of the annular sealing ring is an improvement over seals integrated into the cap or lid as a better secondary seal is created with no cutting of the cap or tube head, and therefore no generation of plastic strings or dust during cap application.

The container head of the invention finds application in the packaging and dispensing of a variety of consumable or purchased goods or products including consumable products such as personal care products (e.g., soaps, shampoos, make-up, insect repellents, and the like); first aid products (e.g., ointments, sunscreens, and the like); cleaners (e.g., detergents and cleaning solutions); paints; and foodstuffs (e.g., yogurt, cheese-like products, jelly, oils, condiments, and the like). The instant invention is a significant improvement in the manufacture of containers as it provides a secondary seal to the primary package seal provided by the seal typically contained in the cap thread area. On threaded caps the primary seal ring is typically a V-seal ring which contacts the land at the top of the container head and seals the V against the land as the cap is screwed or snapped onto the container. In snap-on cap designs, the snap-in bead, which holds the cap in place, generally creates the primary seal. While the primary seal is designed to keep the product from leaking out of the container, the secondary seal, provided by the present invention, is intended to keep foreign matter from entering between the space between the cap and the container head. This secondary seal also provides another purpose in that it seals the container and prevents leakage if the primary seal fails. This is important when the cap is not properly closed thereby causing the product to leak past the primary seal. The secondary seal prevents leakage if the cap is not screwed back tightly on the tube.

Claims

1. A container head with a drip-less seal comprising a shoulder having an annular sealing ring, wherein the annular sealing ring forms a fluid tight seal with the interior surface of a container cap.

2. The container head of claim 1, further comprising a container body.

3. A method for producing a container head with a drip-less seal comprising molding a container head material into a container head with an annular sealing ring integrated into the shoulder thereof thereby producing a container head with a drip-less seal.