Patent Application
20130220862
This invention relates to a biodegradable label. More specifically the invention relates to a biodegradable label made of paper, particularly on packaging of fresh food products such as fruits and vegetables sold in compostable and biodegradable bags.
Due to the increased awareness of environmental matters, there is an increasing need for ecologically sustainable products. Use of biodegradable plastic as packaging material has increased during the last years. In many cases, however, a problem is created in that containers and packages of products may contain biodegradable materials but also nondegradable, environmentally harmful materials. Such containers and packages are hard to compost successfully because that would require separation of the biodegradable and nondegradable materials.
Fresh food products, such as fruits and vegetables are often sold in various kinds of bags, such as paper bags, boxes, or in plastic net bags. US patent application publication US2009/0180717 discloses one such plastic net bag, where the bag is formed from a tubular mesh body fabricated at least partially of plastic material, and the product label is heat sealed to the tubular mesh body to form a heat weld at the ends of the tubular body, thereby closing the ends of the tubular body. The state of the art is to use non-compostable thermoplastic for the label to enable the heat welding process. Thus the bag disclosed in US2009/0180717 uses non-degradable plastic as the material of the net bag as well as of the label.
European patent application publication EP1176104 discloses a plastic net bag where the label is used to close the ends of the tubular net and to form a handle for the bag. Similarly, as in the above mentioned patent application, here too the bag comprises only non-degradable thermoplastic.
US patent application publication US 2008/0317985 provides an improvement to US2009/0180717 in that the tubular plastic net bag is made of compostable mesh.
Thus, the state of the art for the bags for fresh food products such as fruits and vegetables therefore provides plastic net bags, made of biodegradable thermoplastic or of compostable plastic and the product labels necessarily have to include non-degradable thermoplastic, because the tubular net bags are closed at the ends by heat sealing and the state of the art does not know a method to adapt the currently used machinery for fully non-degradable materials. Accordingly, the bag necessarily includes either only non-degradable plastic products or a combination of non-degradable and compostable plastic products. From the environmental point of view, such solutions are not good enough because composting a product with any amount of non-degradable plastic is not successful and would require separation of the compostable and non-compostable components. There is currently not a single product nor a method to make a plastic net bag with a label attached to it where only biodegradable material would be used.
U.S. Pat. No. 7,618,694 provides a biodegradable label for in-mold forming for attachment of a surface of a biodegradable container. The label comprises a laminate film having a film comprising a biodegradable resin and a film comprising a heat sealable-biodegradable resin. The label is disposed directly on the mold cavity surface or mold surface and the label will thus be part of the wall surface of the container.
U.S. Pat. No. 5,294,283 discloses a labeling machine for net bags. This machine is capable of printing labels of various forms. U.S. Pat. No. 7,100,658 discloses a machine for manufacturing, filling and closing mesh bags. The machine is capable of manufacturing, filling and closing tubular mesh bags by heat welding a thermoplastic label at the ends of the tubular net.
Other patents, such as U.S. Pat. No. 6,449,929; U.S. Pat. No. 6,164,359 and U.S. Pat. No. 5,845,467 disclose other machines currently in use to make and label net bags for use in fresh food packaging.
Accordingly, the current state of the art uses machinery that necessarily requires heat sealing of product labels to close the tubular net bags. According to current practices and understanding the only materials usable in such machines are non-degradable thermoplastic labels. Therefore, there are currently no product labels that would be totally biodegradable and compatible for the machinery used to make the plastic tubular net bags. Nor is there a method to use fully biodegradable product labels for such tubular net bags. The instant invention provides a solution to this problem.
The present invention provides solution for the above described problems by providing a biodegradable label for labeling tubular net bags, said label consisting of a paper layer having a lower side and an upper side, the upper side having information printed on water based ink or UV cured ink and the lower side being laminated with biodegradable plastic.
It is thus an object of the invention to provide a biodegradable label for use in connection with fresh food product packaging, especially with mesh bags.
It is another object of the invention to provide a biodegradable label for use in connection with compostable and biodegradable netting.
It is another object of the invention to provide a biodegradable label for use in connection with tubular compostable and biodegradable plastic net bags for packing fruits and vegetables.
It is yet another object of the invention to provide a fully compostable net bag for packing fruits and vegetables.
It is yet another object of the invention to provide a fully compostable or biodegradable label optimized for use with the machines used to product fruit and vegetable net bags.
Still another object of the invention is to provide an economic method to make a fully compostable plastic net bag with a label for packing fresh food products, such as fruits and vegetables.
It is a further object of the invention to provide a biodegradable net bag for packing fresh produce, said bag consisting of a tubular net made of biodegradable or compostable plastic and having two open ends, and two biodegradable labels consisting of a paper layer having a lower side, an upper side, two terminal ends and two side ends, the upper side having information printed on water based or UV cured ink and the lower side being laminated with biodegradable plastic, wherein the paper layer is made of paper having a thickness of 50 to 60 LB, and the biodegradable plastic being biodegradable polyethylene; wherein the biodegradable labels are laid on opposite sides of the tubular net and heat of 175° C. is applied along the two terminal ends and the two side ends of the labels, whereby the labels are attached to the tubular bag along the two terminal ends and the two side ends, and wherein the tubular bag is closed from its open ends by applying heat of 175° C. on the ends, thereby forming a seal having the open ends of the bag sealed between the terminal ends of the biodegradable labels.
Reference will now be made in detail to presently preferred compositions, embodiments and methods of the present invention, which constitute the best modes of practicing the invention presently known to the inventor. The invention is now described in reference to the
A biodegradable label of the present invention comprises a paper label laminated with a biodegradable plastic film.
The paper label is preferably made of paper having a thickness between 50 and 60 LB, preferably 55 LB. The paper is preferably virgin paper, but may also be recycled paper. The preferred width of the label is between 2⅞″ to 6¾″. The paper label may contain product information, logos, advertisement or other information. Such information is provided on the paper label with sustainable inks, such as UV cured inks or water based inks. The adhesive used for the lamination is preferably biodegradable polyethylene. The adhesive may be high density polyethylene (HDPE) or low density polyethylene (LDPE) from 0.4 mil to 1 mil. In preferable embodiment 0.75 mil LDPE is used. The laminate is attached only to the back side of the paper label.
The laminate is attached to the paper with conventional lamination processes, such as adhesive lamination, solvent lamination, hot melt lamination or UV lamination. Surprisingly, a laminated label according to this invention may be attached to the mesh bag by using heat of 175° C. According to this invention, the label is attached to the bag by applying heat of 175° C. along all four sides of the laminated label to attach all the sides of the label to the bag. According to a preferred embodiment one label is attached on one side of the bag and another label is attached on the other side of the bag. The tubular bag is closed from the upper and the lower ends by sealing the ends preferably by applying heat, whereby the end seals are formed by the ends of the tubular bag squeezed between the ends of the two labels.
The existing prior art does not disclose anything similar and actually the existing prior art suggests that this approach would not even be possible. According to the existing prior art and the current practices, the only way to close the tubular mesh bag would be by heat melding a non degradable thermoplastic label over the open ends of the tubular bag. The instant invention provides a biodegradable laminated paper label that is used to close the ends of the tubular bag by using heat and additionally the biodegradable label is attached to the bag from all four sides by using heat.
The total thickness of the label is 2.5 to 4 mils (one thousands of an inch) depending on the recipe of the plastic and the thickness of the paper. According to a preferred embodiment the labels are provided in the form of continuous rolls.
The biodegradable label according to this invention is compatible with the currently known machinery for packing and labeling fresh food products in tubular net bags. The biodegradable label according to this invention is capable of making the package degradable using biodegrade components or compostable components.
This application claims priority of U.S. provisional application No. 61/602,729 filed on Feb. 24, 2012 the contents of which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61602729 | Feb 2012 | US |
