WO2011073496A1

WO2011073496A1 - A pallet and a method for manufacturing a pallet

Info

Publication number: WO2011073496A1
Application number: PCT/FI2009/051003
Authority: WO
Inventors: Liisa Lehtinen; Ari Kinnunen; Piia Peltola; Dan O'connell
Original assignee: Upm-Kymmene Corporation
Priority date: 2009-12-16
Filing date: 2009-12-16
Publication date: 2011-06-23

Abstract

The invention relates to a pallet and to a method for manufacturing a pallet, wherein the pallet is formed from a starting material containing at least plastic- based components by a manufacturing method based on heat and pressure. According to the invention the starting material contains at least one adhesive laminate waste component.

Description

A PALLET AND A METHOD FOR MANUFACTURING A PALLET

FIELD OF THE INVENTION

The invention relates to the pallet defined in the preamble of claim 1 and to the method for manufacturing a pallet defined in the preamble of claim 14.

BACKGROUND OF THE INVENTION

Known from the prior art are different pallets and methods for manufacturing them. It has been known to manufacture pallets from wood, plastic and different composite materials. In addition, it is known from the prior art to reinforce pallets by metal ribbons or equivalent metal reinforcements.

It is known from the prior art to manufacture pallets from recycling plastic mainly consisting of polyethylene and polypropylene.

It is known that in conventional recycling of plastic the aim has been as pure a plastic fraction as possible in order to provide undisturbed operation of the recycling process. Respectively, in conventional recycling of paper the aim has been as pure a paper fraction as possible. It has not been possible earlier to utilize waste material that contains siliconized components as recycling material in the recycling ^' of neither plastic nor paper. Especially the siliconized polyethylene terephthalate, also used in the manufacture of adhesive items, has been a material that has been difficult to recycle. It has not been desired that a paper fraction or plastic fraction to be recycled contains silicone-based components. Especially the recycling of adhesive laminate waste has been problematic because it is a combination of wastes containing plastic- and/or fiber-based components, adhe- sive and generally siliconized material and polyethylene terephthalate .

OBJECTIVE OF THE INVENTION

An objective of the invention is to eliminate the preceding defects and disclose a new type of a pallet formed from recyclable materials and being further recyclable, and a method for manufacturing a pallet.

SUMMARY OF THE INVENTION

The pallet and method for manufacturing a pallet according to the invention are characterized by what has been presented in the claims.

The invention is based on a pallet formed from a starting material containing at least plastic- based components and formed by a manufacturing method based on heat and pressure. According to the invention the starting material contains at least one adhesive laminate waste component.

In addition, the invention is based on a method for manufacturing a pallet, wherein the pallet is formed from a starting material containing at least plastic-based components by a manufacturing method based on heat and pressure. According to the invention the employed starting material encompasses at least one adhesive laminate waste component. Preferably the starting material is provided in a desired form and size e.g. by crushing before the manufacture of the pallet .

In this connection a plastic-based component stands for any component substantially containing plastic, e.g. polyethylene, polypropylene, polyethylene terephthalate or equivalent plastic.

In one embodiment the starting material is formed from one starting material component. In one embodiment the starting material is formed from more than one starting material component.

In one embodiment of the invention the starting material contains a fiber-based component. In one embodiment the fiber-based component is formed from wood fibers and/or other botanical fibers, e.g. straw, reed or flax. In one embodiment the starting material contains paper-based material as a fiber-based component .

In this connection a paper-based material stands for any paper-based material preferably mainly formed from plant fibers, such as wood fibers. The paper-based material may be formed from chemical pulp fibers from which lignin has been removed and/or from fibers that contain lignin. For example the fibers obtained from the manufacture of TMP pulp contain lignin. In a preferred embodiment the paper based material contains plant fibers in an amount of more than 50 w-% of the material. If the paper-based material con- sists of lignin-free fibers, the color of the paper and thus herein also the color of the composite product is pale. The absence of l^'ignin also brings weather resistance to the product. Lignin is a coloring element, so its absence allows the use of a larger color scale, e.g. also the pale and bright colors.

In one embodiment the pallet is formed from a starting material containing fiber-based and plastic- based components. The starting material may contain any plastic-based and/or fiber-based components. In addition, the starting material may contain smaller amounts of other components. In one embodiment the proportions of plastic-based components may vary between 10 and 100 % in the pallet. In one embodiment the proportions of fiber-based components may vary be- tween 0 and 90 % in the pallet. In one embodiment the pallet is formed from a starting material containing plastic-based and paper-based components.

In one embodiment of the invention the starting material contains siliconized material, e.g. siliconized film material. The siliconized material may be silicone-based or silicone compound -based material or silicone-based compound that may be part of another material or provided on the surface of another material. Alternatively the siliconized material is plastic- based and/or fiber-based material, the surface of which is siliconized by a silicone-containing compound or compounds .

In one embodiment of the invention the starting material contains glue matter which preferably comes from used adhesive laminate waste. The glue matter increases binding between particles.

In one embodiment of the invention the starting material contains polyethylene terephthalate (PET) either as an independent component or as part of a starting material component. Preferably the polyethylene terephthalate is not fused at the process temperature of the manufacture of the pallet, in which case it acts as excellent filler. In one embodiment the pallet contains 0 to 80 % of polyethylene terephthalate.

Preferably the starting material is at least partially recycling material. More preferably the starting material is mainly recycling material.

In one embodiment of the invention the pallet is formed mainly, in an amount of more than 50w-%, from adhesive laminate waste. In one embodiment the pallet contains one adhesive laminate waste component. In one embodiment the pallet contains more than one adhesive laminate waste component.

In one embodiment the adhesive laminate waste contains adhesive material on which a layer of glue matter has been provided, and fitted on the layer of glue matter as a protective sheet for the layer of glue is release material that can be easily released at the application site of the adhesive item. In one preferred embodiment the adhesive material and/or the release ma- terial contains a wood fiber -based component and/or plastic- or polymer-based or other organic component. Also, the use of different inorganic materials is possible. In one embodiment the adhesive and/or release material is wood fiber -based paper, paperboard or the like. In one embodiment the wood fiber -based paper, paperboard or the like contains or is treated with plastic- or polymer-based material. In one embodiment the adhesive and/or release material may substantially be formed from plastic- or polymer-based material. In one embodiment the release material is mainly formed from plastic-based material, containing e.g. polypropylene, polyethylene, polyethylene terephthalate or their mixtures. In one embodiment the release material contains siliconized material, e.g. siliconized film material. In one embodiment the release material is coated with silicone-based material or compound. In one embodiment the release material contains siliconized polyethylene terephthalate (PET) .

In one embodiment finished adhesive laminate products, waste material produced from them and/or in their manufacture may be used as adhesive laminate waste in the manufacture of the pallet. In addition, reject material from production and recycling material from the upgrading step or end use applications of ad- hesive laminate products may be used. In one embodiment the adhesive laminate waste comes from adhesive laminate production which mainly produces production reject waste, edge trimming waste cut off from rolls, and roll ends, from the adhesive laminate printing plant which mainly produces roll ends and adhesive material left over from die-cutting of stickers and labels, and re- ject waste, and/or from the adhesive laminate end user customer who pastes the printed stickers and labels or the like on products. The waste from the end user is mainly release material, roll ends and waste from the finished product.

In one embodiment the adhesive laminate waste may contain a variable number of different adhesive laminate waste components, such as adhesive material, glue matter and release material. The glue matter may preferably be in connection with adhesive material and/or release material. In one embodiment the adhesive laminate waste contains 0 to 100 % of adhesive material, 0 to 100 % of siliconized film, i.e. release material, and 0 to 40 % of glue matter.

In one embodiment the pallet may contain, in addition to plastic-based and/or fiber-based components, different additives and/or additional plastic, e.g. to improve the mechanical properties, outdoor durability or processability of the product.

In one embodiment of the invention at least one additive is added to the starting material in connection with the manufacture of the pallet. E.g. coloring agent, fire retardant, adhesion promoter, anti- mildew agent, antioxidant and uv stabilizer may be used as additives. Additives which may preferably be added to the pallet include fibrous materials, organic fillers, inorganic fillers, powdery reinforcements, powdery additives, talc, wood fibers, chemical pulp fibers, paper and their combinations. In one embodiment where adhesive laminate waste material that contains lignin-free fibers is used as starting material the pallet product contains a coloring agent which may be selected from a large color scale, from pale colors all the way to dark colors. In one embodiment, especially if the starting material contains polyethylene tereph- thalate or fibers not being naturally compatible with other raw materials, a coupling agent is added to the starting material.

In one embodiment additional plastic is added to the starting material in connection with the manu- facture of the pallet. Virgin plastic and/or recycling plastic may be used as additional plastic. Pallets may be manufactured with or without additional plastic. E.g. polyolefin, polypropylene, polyethylene (HDPE, LDPE) , polyethylene terephthalate or other suitable plastic or their mixture may be added as additional plastic to starting material that consists of adhesive laminate waste material to manufacture the pallet. In one preferred embodiment recycling plastic is at least partially used as additional plastic. In one embodiment recycling plastic is mainly used as additional plastic.

In one embodiment the pallet is formed so as to contain 50 to 100 w-% of plastic- and/or fiber-based components. In one embodiment the pallet contains additional plastic in an amount of less than 50w-%. In one embodiment the pallet contains additives in an amount of less than 50w-%. In one embodiment the pallet contains 0 to 30 % of fiber-based material, 0 to 30 % of polyethylene terephthalate and 20 to 80 % of recycling plastics, such as polyethylene and/or polypropylene. Part of the materials may contain siliconized components and glue matter.

In one embodiment the starting material can be provided in particle form, such as in the form of particles, crushed products, chopped products or ag- glomerates, and the pallet is formed from the particle form starting material.

The pallet manufacturing method may include a pretreatment step in order to pretreat the starting material. E.g. a mixing step, agglomerate forming step, granulation step, their combination or the like may be used as a pretreatment step. In one embodiment the ad- ditives and/or the additional plastic can be added to the starting material during the pretreatment step.

In one embodiment the starting material is compacted by heat and pressure into a pallet and the resulting pallet is preferably cooled in order to form the end product.

In one embodiment of the invention the pallet is formed by injection molding.

Any method known per se in the art and suita- ble for the purpose of use may be used in the manufacture of the pallet according to the invention. E.g. extrusion technique, injection molding technique, compression molding, mold casting, mold compression technique, their combinations or another known method can be used as manufacturing methods.

The pallet may have any predetermined shape known per se and a shape determined by the purpose of use. In one embodiment the pallet includes a planar base that may be a substantially continuous plane or that may have planar structures forming a plane and opening structures therebetween, provided in a desired manner and into a desired pattern. In one embodiment the pallet includes foot structures, optionally more than two, preferably 2 to 9. The dimensions of the pallet may vary according to the standards and the purpose of use of the pallet.

In one embodiment of the invention the pallet includes at least one support element in order to reinforce the pallet and improve the mechanical properties. The support element may be, depending on the purpose of use, batten-type, rod-type, mat-type or of another suitable shape. In one embodiment the pallet includes more than one support element. In one embodiment the pallet includes two support elements. In one embodiment the pallet includes three support elements. In one em- bodiment the pallet includes 4 to 10, in one embodiment 5 to 6 support elements.

In one embodiment of the invention the support element is provided in connection with the pallet in the lengthwise direction of the pallet. In one embodiment the support element is provided in connection with the pallet in the cross direction of the pallet. In one embodiment support elements are provided to the pallet in lengthwise and cross directions of the pal- let, preferably at an angle of approximately 90° to each other.

In one embodiment of the invention the support element is provided substantially within the pallet. In one embodiment the support element provided within the pallet is rod-type.

In one embodiment of the invention at least one site, e.g. a row, groove, opening, tunnel or equivalent is formed in connection with the pallet, substantially within the pallet, for the support ele- ment, preferably in connection with the manufacture or alternatively after the manufacture of the pallet. In one embodiment the site is provided in connection with the base of the pallet. In one embodiment the site is provided in connection with the foot of the pallet. When the pallet has a site for a support element, the support element can be provided, e.g. threaded, in connection with the pallet at any desired stage.

In one embodiment of the invention a support element is provided to at least one surface of the pallet. In one embodiment a mat-type support element is provided to the top and/or bottom surface of the pallet .

In one embodiment the support element is provided in a mold before filling the mold with the starting material. When the starting material is led to the mold, the support element remains at least par- tially within the material, in which case a separate site for the support element is not needed. If it is desirable to locate the support element to or on the surface of the pallet, the support element is located relative to the mold in such a manner that the starting material contacts the support element while filling the mold, fastening at the same time the support element to the resulting pallet.

In one embodiment the support element is formed from fiber-based material, metal, such as aluminum, plastic, fiber reinforced plastic, fiberglass, their mixtures or other suitable material. In one embodiment the support element is formed from recyclable and reusable material. In one embodiment of the invention at least one support element is formed mainly from fiber-based material, e.g. wood fiber and/or plant fiber -based material. In one embodiment the support element is formed from wood. In another embodiment the support element is formed from plywood.

In one preferred embodiment at least one support element is formed from a material that is recyclable in connection with the remanufacture of the pallet, in which case the support element may be recycled together with the pallet.

In one embodiment the support element is formed from material that is recyclable in connection with the remanufacture of the pallet, e.g. wood or plywood, and/or from material that is withdrawn in connection with the remanufacture of the pallet, e.g. metal or fiberglass. The material to be withdrawn, i.e. the non-recyclable material, is removed before recycling the pallet, e.g. before crushing, and the recyclable material is allowed to remain on the pallet. In one embodiment the material to be withdrawn is located to the surface of the pallet or in separate support element site grooves or equivalent, wherefrom it can be easily removed before recycling and remanu- facture of the pallet.

In one embodiment a surface layer, coating or the like, formed from a desired material, is coupled, e.g. by gluing, on the resulting pallet substantially in connection with the manufacture or alternatively after the manufacture of the pallet.

The pallet and its manufacturing according to the invention have many important advantages compared with the prior art.

Thanks to the invention an easily recyclable pallet is provided. The pallet according to the invention may be recycled either as such for reuse or for raw material to the manufacture of new pallets. Alter- natively a pallet that has reached the end of its lifetime can be burnt and this way utilized in energy production. The support elements in connection with the pallet can be removed and utilized in recycling depending on the employed material, and recycling pur- pose. For example if the support elements have been manufactured from a material that can be crushed and recycled together with the pallet and the material obtained this way can be reused in the manufacture of pallets, the support elements need not be removed.

In addition, an advantage of the invention is an inexpensive product according to sustainable development, thanks to the use of recycling materials. The pallet is manufactured from recyclable adhesive laminate waste. In addition, the waste material that con- tains polyethylene terephthalate and/or siliconized material can be utilized in the manufacture of the pallet .

As an advantage, e.g. in comparison with wooden pallets, the pallet according to the invention has a lower square weight while being at the same time strong. Wooden pallets cannot be used e.g. in food- stuff transportations because they may contain insects and worms. There is no such risk with the pallet according to the invention, and the pallet qualifies as such for the standard ISP -15. In addition, - the pal- lets according to the invention are more hygienic than the pallets manufactured from wood. Further, the pallet according to the invention can be easily reinforced by supports structures.

By the invention, an easily industrially ap- plicable pallet for several purposes of use is achieved. The pallet according to the invention can be used in conventional purposes of use of pallets, e.g. in different transportations of goods at different stages of logistics chains.

LIST OF FIGURES

Fig. 1 presents one pallet according to the invention, and

Fig. 2 presents another pallet according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following, the invention will be described by detailed exemplary embodiments, referring to the accompanying drawings.

Example 1

Pallets according to the invention were formed from a starting material mainly formed from adhesive laminate waste. Adhesive laminate waste was used mainly as the starting material in an amount of approximately 70w-%. The adhesive laminate waste contained approximately 20% of an adhesive material component mainly containing chemical pulp -based, i.e. lignin-free, paper-based material, and approximately 70% of a plastic-based release material component con- taining PET, PE, PP and silicone-based components, and approximately 10% of glue matter mainly in connection with adhesive material and release material. Polypropylene was mixed to the chopped starting material as additional plastic in an amount of approximately 25w-% and additives in an amount of approximately 5w-% in a pretreatment device, and the starting material was formed into agglomerates that were provided in the form of a pallet by injection molding. The resulting pallet was cooled to room temperature.

Fig. 1 presents the resulting pallet 1. The pallet includes a planar base 2, which in this embodiment is a substantially continuous plane. In addition, the pallet includes nine foot structures 3 provided in banks of 3 x 3 and connected to each other. In an alternative embodiment the pallet may have six foot structures if it is a so-called smaller store pallet.

Fig. 2 presents a pallet that corresponds to the pallet of Fig. 1 in other respects except for the base 2. In this embodiment the base 2 is not a fully continuous plane but includes planar structures 7 and openings 6 disposed in a predetermined manner.

The base part 2 of the pallets of Fig. 1 and 2 additionally includes site grooves 4a and 4b for support elements 5 in the lengthwise and cross directions of the pallet at the foot banks 3 so that the site grooves 4a and 4b intersect. The support elements 5 are located in sites 4a and 4b in such a manner that the first six shorter rod-type support elements are provided in three grooves 4a of a first direction of the pallet so that two support elements are located in each groove 4a at a distance from one another without crossing the grooves 4b of a second direction. Hence, the first support elements are located in each groove 4a of a first direction substantially between the grooves 4b of a second direction. Provided in site grooves 4b of a second direction of the pallet are another three rod-type support elements 5 which are longer than the first support elements and extend for the entire length of the groove 4b from one end of the base 2 to the other. In this embodiment the support elements are formed from plywood.

Example 2

Pallets according to the invention were formed from a starting material mainly formed from adhesive laminate waste. Adhesive laminate waste was used mainly as the starting material in an amount of approximately 90w-% . The adhesive laminate waste contained release material containing mainly plastic- based material, such as PET, glue matter and a silicone-based component and a minor amount of fiber-based components. Polyethylene was mixed to the crushed starting material as additional plastic in an amount of approximately 10w-% in a pretreatment device, and the starting material was formed into a pallet by injection molding.

The structure of the pallet was equivalent to Example 1 and Fig. 1.

Example 3

Pallets according to the invention were formed from a starting material formed from adhesive laminate waste. Approximately 100w-% of adhesive laminate waste was used as the starting material. The adhesive laminate waste contained release material containing mainly plastic-based material, such as PET, glue matter and a silicone-based component and a minor amount of fiber-based components. The pallet was formed from the starting material by injection molding . The pallet was equivalent to the pallet presented in Example 1 and Fig. 1 in other respects except without support elements and without their site grooves .

It was discovered that pallets were easily provided from waste material by the injection molding technique known per se in the experiments. The pallets were reusable or alternatively they could be utilized in their entirety, including the support elements in Examples 1 and 2, as raw material in the manufacture of new pallets or in energy production by crushing the used pallets. The pallet according to the invention lends itself as different embodiments to be used in the most different applications.

The invention is not limited merely to the examples referred to above; instead, many variations are possible within the scope of the inventive idea defined by the claims.

Claims

1. A pallet (1) formed from a starting material containing at least plastic-based components by a manufacturing method based on heat and pressure, c h a r a c t e r i z e d in that the starting material contains at least one adhesive laminate waste component .

2. The pallet according to claim 1, c h a r - a c t e r i z e d in that the pallet (1) is mainly formed from adhesive laminate waste.

3. The pallet according to claim 1 or 2, c h a r a c t e r i z e d in that the starting material contains fiber-based components.

4. The pallet according to any one of .claims 1 to 3, c h a r a c t e r i z e d in that the starting material contains siliconized material.

5. The pallet according to any one of claims 1 to 4, c h a r a c t e r i z e d in that the starting mate- rial contains adhesive.

6. The pallet according to any one of claims 1 to 5, c h a r a c t e r i z e d in that the starting material contains polyethylene terephthalate .

7. The pallet according to any one of claims 1 to 6, c h a r a c t e r i z e d in that the starting material contains additional plastic and/or additive.

8. The pallet according to any one of claims 1 to 7, c h a r a c t e r i z e d in that the pallet (1) includes at least one support element (5) in order to reinforce the pallet.

9. The pallet according to claim 8, c h a r a c t e r i z e d in that the support element (5) is provided in connection with the pallet (1) in the lengthwise direction of the pallet.

10. The pallet according to claim 8 or 9, c h a r a c t e r i z e d in that the support element (5) is provided in connection with the pallet (1) in the cross direction of the pallet.

11. The pallet according to any one of claims 8 to 10, c h a r a c t e r i z e d in that the support element (5) is provided substantially within the pallet (1) ·

12. The pallet according to any one of claims 8 to 11, c h a r a c t e r i z e d in that the support element (5) is provided to at least one surface of the pallet (1) .

13. The pallet according to any one of claims 8 to 12, c h a r a c t e r i z e d in that at least one support element (5) is mainly formed from a fiber-based material .

14. A method for manufacturing a pallet, wherein the pallet is formed from a starting material containing at least plastic-based components by a manufacturing method based on heat and pressure, c h a r a c t e r i z e d in that at least one adhesive laminate waste component is used as the starting material. ^~

15. The method according to claim 14, c h a r a c t e r i z e d in that the pallet is mainly formed from adhesive laminate waste.

16. The method according to claim 14 or 15, c h a r a c t e r i z e d in that additional plastic and/or additive is added to the starting material.

17. The method according to any one of claims 14 to 16, c h a r a c t e r i z e d in that the starting material is pretreated.

18. The method according to any one of claims

14 to 17, c h a r a c t e r i z e d in that the pallet is formed by injection molding.

19. The method according to any one of claims 14 to 18, c h a r a c t e r i z e d in that at least one support element is provided in connection with the pallet in order to reinforce the pallet.

20. The method according to claim 19, c h a r a c t e r i z e d in that at least one site for the support element is formed in connection with the pallet .