Patent Application
20120305121
The present invention relates generally to a fiberboard tube and closure assembly. More specifically, the present invention relates to a fiberboard tube with a heat sealable inner layer in which the closure piece is sealed thereto.
Fiberboard is a paper-like material usually over 0.01 inches (0.25 mm) thick sometimes called paperboard or cardboard. Cardboard might also be any heavy paper-pulp based board. Fiberboard tubes are conventionally formed by adhesively bonding two or more continuous strips of paper to each other in overlapping layers around a cylindrical mandrel and then cutting the fiberboard cylinder or tube thus formed to desired length. The open ends of the fiberboard tube can then be closed using a suitable end closure to form a container that is both light and strong.
A variety of end closures are known in the art for closing the open end of a fiberboard tube. A very popular type is known in the industry as a plastic end cap or plug. Plastic plugs are relatively simple to manufacture, inexpensive and lightweight. However, it is often the case that the manufacturing process of producing the fiberboard tube with the plastic top is not environmentally friendly.
According to the present invention, a method to assemble a biodegradable tube and closure component for containing a viscous substance is disclosed. The method includes providing a fiber board tube with a heat sealable inner surface; providing a polymer closure component; inserting the closure component into one end of the fiber board tube; and welding the closure component to the one end of the fiber board.
Further according to the present invention, a biodegradable tube and closure component for containing a viscous substance comprises: a fiber board tube with a heat sealable inner surface; a polymer closure component inserted into one end of the fiber board tube; and the closure component welded to the one end of the fiber board.
The structure, operation, and advantages of the present invention will become further apparent upon consideration of the following description taken in conjunction with the accompanying figures (FIGs.). The figures are intended to be illustrative, not limiting. Certain elements in some of the figures may be omitted, or illustrated not-to-scale, for illustrative clarity. The cross-sectional views may be in the form of “slices”, or “near-sighted” cross-sectional views, omitting certain background lines which would otherwise be visible in a “true” cross-sectional view, for illustrative clarity.
In the drawings accompanying the description that follows, both reference numerals and legends (labels, text descriptions) may be used to identify elements. If legends are provided, they are intended merely as an aid to the reader, and should not in any way be interpreted as limiting.
In the description that follows, numerous details are set forth in order to provide a thorough understanding of the present invention. It will be appreciated by those skilled in the art that variations of these specific details are possible while still achieving the results of the present invention. Well-known processing steps are generally not described in detail in order to avoid unnecessarily obfuscating the description of the present invention.
In the description that follows, exemplary dimensions may be presented for an illustrative embodiment of the invention. The dimensions should not be interpreted as limiting. They are included to provide a sense of proportion. Generally speaking, it is the relationship between various elements, where they are located, their contrasting compositions, and sometimes their relative sizes that is of significance.
In the drawings accompanying the description that follows, often both reference numerals and legends (labels, text descriptions) will be used to identify elements. If legends are provided, they are intended merely as an aid to the reader, and should not in any way be interpreted as limiting.
The present invention is directed to an innovative and environmentally conscious manner of manufacturing a fiberboard tube with a closure piece. In broad terms, low temperature ultrasonic welding or heat sealing is utilized to secure, preferably hermetically, the closure piece to the fiberboard tube.
Referring to
The fiberboard tube and closure assembly 10 is designed to be biodegradable when it is disposed of after use. The fiberboard tube and closure assembly 10 includes a hollow cylindrical tube 12 with two opposite open ends 14 and 16 (as seen in
The heat sealable inner lining 17 is constructed of plastic materials, either a mono layer or multiple layers, wherein at least one is a thermoplastic layer, that can be heat sealed and/or ultrasonic sealed. Further the closer piece 20 can also be constructed from the same materials. These include:
An important advantage of the forming the hollow cylindrical fiberboard tube 12 is that approximately 40-50% of the plastic material has been eliminated from a conventional plastic tube typically used to house a viscous substance.
As seen in
The flip-top closure piece 20 can be mounted to the open end 14 of the cylindrical tube 12 by inserting the cylindrical lip 21 having an outer diameter D1 into the open end 14 of hollow cylindrical tube 12. The end 23a of cylindrical top section 23 abuts against the cylindrical wall of the open end 14 of tube 12. Preferably, the cylindrical lip 21 forms a friction fit with the inner wall 18 of the hollow cylindrical tube 12. Closure piece 20 uses has a cylindrical lip 21 which is shorter than a typical cylindrical lip of a prior art flip-top closure piece which is about 40% longer than the cylindrical lip of the present invention. The use of the narrower cylindrical lip for the flip-top closure piece of the present invention is designed to use less plastic than the traditional closure piece in an effort to make the fiberboard tube and closure assembly 10 as environmentally friendly as possible.
The cylindrical lip 21 of closure piece 20 is fitted into the open end 14 of the hollow cylindrical tube 12 and then secured therein using ultrasonic sealing, also referred to as ultrasonic welding wherein the closure piece 20 is bonded and sealed within the open end of the hollow cylindrical tube 12 by using localized heat developed by vibratory mechanical pressure at ultrasonic frequencies. The ultrasonic welding device 30, as seen in
In the prior art, closure piece 20 is fitted into the open end 14 of the hollow cylindrical tube 12 and then secured therein using an adhesive. Being that the adhesives used in the prior art are not biodegradable this is not currently an environmentally friendly option due to the biodegradability. For an adhesive to meet eco-friendly standards, the ASTM defines what constitutes “biodegradability.” Biodegradability means that a product is “capable of undergoing decomposition into carbon dioxide, methane, water, inorganic compounds, or biomass in which the predominant mechanism is the enzymatic action of microorganisms that can be measured by standardized tests, in a specific period of time, reflecting available disposal conditions.”
It is also within the terms of the invention to utilize heat sealing, also known as heat welding to hermetically secure a closure piece 20 fitted into the open end 14 of the hollow cylindrical tube 12. As discussed before, the cylindrical tube 12 can have an inner layer 17 comprising a uniform thermoplastic monolayer or multiple layers, at least one being thermoplastic. The closure piece can be constructed of a thermoplastic material which is the same as the monolayer or the thermoplastic of the multiple layers. Heat sealing can join two similar materials together or can join dissimilar materials, one of which has a thermoplastic layer. In this case, either the closure piece 20, or the hollow cylindrical portion 12, or both may be a thermoplastic material in order to effectively utilize heat sealing. The temperature range of heart sealing is between about 175° C. and 275° C. The breadth of this temperature range is due to a variety of factors. These factors include various types of plastics that may be used with differing melting points, the thickness of the hollow cylindrical fiberboard tube 12 as well as the thickness of its inner plastic layer 17, and the speed of production which when increased, requires higher heat or frequency, as well as increased dwell time, and pressure adjustments.
As seen in
Once the substance has been injected into the hollow cylindrical portion 12, open end 16 is closed and sealed at 32, as seen in
In use, hollow cylindrical tube 12 of the completed fiberboard tube and closure assembly 10, after it has been filled with a substance and has the end 18 sealed closed to form a biodegradable fiberboard tube and closure assembly 40 filled with a viscous substance 10, as shown in
Although the invention has been shown and described with respect to a certain preferred embodiment or embodiments, certain equivalent alterations and modifications will occur to others skilled in the art upon the reading and understanding of this specification and the annexed drawings. In particular regard to the various functions performed by the above described components (assemblies, devices, etc.) the terms (including a reference to a “means”) used to describe such components are intended to correspond, unless otherwise indicated, to any component which performs the specified function of the described component (i.e., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary embodiments of the invention. In addition, while a particular feature of the invention may have been disclosed with respect to only one of several embodiments, such feature may be combined with one or more features of the other embodiments as may be desired and advantageous for any given or particular application.
