Abstract:
A biodegradable tube and closure component for containing a viscous substance and method for assembling the biodegradable tube and closure component includes a fiber board tube with a heat sealable inner surface and a polymer closure component inserted into one end of the fiber board tube and welded therein by heat or ultrasonically welding. The assembled biodegradable tube and closure component can be filled with a desired viscous substance through an opposite open end of the cylindrical tube and then the opposite open end closed to form a biodegradable fiberboard tube and closure assembly filled with the viscous substance.

Description:
FIELD OF THE INVENTION 
       [0001]    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. 
       BACKGROUND OF THE INVENTION 
       [0002]    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. 
         [0003]    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. 
       SUMMARY OF THE INVENTION 
       [0004]    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. 
         [0005]    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. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    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. 
           [0007]    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. 
           [0008]      FIG. 1  is a three-dimensional side view of the fiberboard tube with an ultrasonically welded closure piece, in accordance with the present invention. 
           [0009]      FIG. 2  is a three-dimensional exploded side view of the fiberboard tube and the closure piece, in accordance with the present invention. 
           [0010]      FIG. 3  is a three-dimensional side view of the fiberboard tube with the ultrasonically welded closure piece and the welder, in accordance with the present invention. 
           [0011]      FIG. 4  is a three-dimensional side view of the fiberboard tube with the ultrasonically welded closure piece in combination with a substance injector, in accordance with the present invention. 
           [0012]      FIG. 5  is a three-dimensional side view of the sealed fiberboard tube with ultrasonically welded closure piece, in accordance with the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0013]    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. 
         [0014]    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. 
         [0015]    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. 
         [0016]    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. 
         [0017]    Referring to  FIG. 1 , a fiberboard tube and closure assembly  10  is illustrated. The fiberboard tube and closure assembly  10  is adapted to house a substance that is injected into the assembly  10 . This substance is generally of a viscous consistency, such as sunscreen or other lotions. 
         [0018]    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  FIG. 2 ) and a closer piece  20  (as shown in  FIG. 2 ). The hollow cylindrical tube  12  is constructed of fiberboard that can be printed thereon and with a heat sealable inner lining  17 . The inner surface or wall  18  of the hollow cylindrical tube  12  is coated with a heat sealable lining  17  that is environmentally friendly. The heat sealable lining  17  can be a uniform thermoplastic monolayer or a material with multiple layers, at least one of which is a thermoplastic layer. As discussed below, heat sealing can join two similar materials together or join dissimilar materials wherein one of which has a thermoplastic layer. 
         [0019]    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:
       ACN Acrylonitrile   BOPP Biaxially Oriented Polypropylene   BON Biaxially Oriented Nylon   CA Cellulose Acetate   CTFE Chlorotrifluoroethylene/Aclar   EAA Ethylene Acrylic Acid   EEA Ethylene-Ethyl Acrylate   EMA Ethylene-Methyl Acrylate   EVA Ethylene-Vinyl Acetate   EVOH Ethylene-Vinyl Alcohol   HIPS High Impact Polystyrene   SUR Ionomer/Surlyn   LDPE Low-Density Polyethylene   LLDPE Linear Low-Density Polyethylene   mPE Metallocene Polyethylene   OPP Oriented Polypropylene   PA Polyamide   PAN Polyacrylonitrile/Barex   PB Polybutylene   PE Polyethylene   PET Poly(Ethylene Terephthalate)/Polyester   PETG Poly(Ethylene Terephthalate) Glycol   PLA Poly(Lactic Acid)   PP Polypropylene   PS Polystyrene   PTFE Polytetrafluoroethylene/Teflon   PUR Polyurethane   PVC Poly(Vinyl Chloride)   PVDC Poly(Vinylidene Chloride)       
 
         [0049]    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. 
         [0050]    As seen in  FIG. 2 , the fiberboard tube and closure assembly  10  has a closure piece  20 , such as a “flip-top” lid that is shown, mounted to the open end  14 . While a flip top closure is shown, it is within the terms of the invention to incorporate any type of closure piece such as but not limited to a disc top, a bullet top, and a top suitable for applying lip balm. The flip-top closure piece  20  includes a cylindrical lip  21  extending from one end  23   a  of the cylindrical top section  23 . The cylindrical lip  21  can have a length of between about 0.125 inches and about 0.5 inches. The top surface of the cylindrical top section  23  (not shown) covers the end of the top section and includes an aperture (not shown) extending there through. The flip top section  25  of the flip-top closure piece  20  is typically mounted by a hinged portion (not shown) to the cylindrical top section  23  and includes a plug that seals the aperture. 
         [0051]    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 D 1  into the open end  14  of hollow cylindrical tube  12 . The end  23   a  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. 
         [0052]    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  FIG. 3 , applies high-frequency ultrasonic acoustic vibrations to the area  12   a  of the tube  12  covering the lip  21 . In practice, the lip  21  is first removably secured within the open end  14  of tube  12  by friction and then the ultrasonic device  30  locally applies the high-frequency ultrasonic acoustic vibrations in the frequency range of operation, i.e., about 20 kHz to about 35 kHz, to the area  12   a  covering the lip  21  to create a strong hermetic seal. This ultrasonic welding technique utilizes low heat and is an environmentally friendly process. Nearly all packaging materials and laminates with a thermoplastic sealing layer or coating are suitable for the use of ultrasonic technology. This is the novel and preferred approach to the mounting of a closure piece  20  which previously was secured within a tube by an adhesive. 
         [0053]    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.” 
         [0054]    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. 
         [0055]    As seen in  FIG. 4 , after the closure piece  20  is fitted into the open end  14  of the hollow cylindrical tube  12 , a substance injector  22  inserts the desired substance, such as sunscreen, lotion, toothpaste, etc. into the open end  16  of the hollow cylindrical tube  12 . This filling process may be done manually, semi-automatically, or with standard tube filling equipment. 
         [0056]    Once the substance has been injected into the hollow cylindrical portion  12 , open end  16  is closed and sealed at  32 , as seen in  FIG. 5 . This heat-sealing process may be made using any method available for sealing plastic tubes as described above. 
         [0057]    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  FIG. 5 . The fiberboard tube  12  of biodegradable fiberboard tube and closure assembly  40  is malleable so that when the user applies pressure to the tube  12 , the contents are forced out through an opening in the closure piece  20  as is conventionally known. 
         [0058]    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.