WO2005070773A1

WO2005070773A1 - Sheet pallet

Info

Publication number: WO2005070773A1
Application number: PCT/JP2005/000675
Authority: WO
Inventors: Kenichi Kobayashi; Masato Kimura
Original assignee: Nippon Petrochemicals Co., Ltd.
Priority date: 2004-01-21
Filing date: 2005-01-20
Publication date: 2005-08-04
Also published as: JP2005231738A

Abstract

A sheet pallet small in thickness and having a sufficient mechanical strength capable of withstanding repeated use. The sheet pallet (1) comprises a reinforced net-like layer (2), a front surface layer (3) stacked on one surface thereof, and a rear surface layer (4) stacked on the other surface thereof. The reinforced net-like layer (2) is formed by stacking, on each other, two sheets of uniaxial oriented fiber films drawn in one direction so that their drawing directions are orthogonal to each other.

Description

Specification

Seatno "Let

Technical field

The present invention relates to a sheet pallet used for logistics transportation.

Background art

[0002] Conventionally, wooden pallets and plastic pallets have often been used as pallets for loading loads during logistics transportation. However, with the recent increase in material flow, sheet pallets have come to be used in order to improve the efficiency of loading and transporting cargo and to improve the efficiency of physical distribution. The sheet pallet has a sheet-like portion on which a load is loaded, and a tab portion extending integrally with the side force of the sheet-like portion. Forklifts equipped with push-pull attachments are used to handle loads loaded on sheet pallets with forklifts. Loading and unloading of the forklift onto the platen is performed by holding the tab with a push-pull attachment and moving the push-pull attachment forward and backward on the platen.

[0003] The sheet pallet itself is very thin! Therefore, it is possible to save storage space while loading a load, and to store a spare sheet pallet that can be used without force. When collecting pallets, compared with conventional pallets, there are significant advantages in storage space and ease of transportation. In addition, since the sheet pallets themselves are lightweight, an empty sheet pallet can be easily transported and operated by a single worker, contributing to more efficient work in factories.

[0004] A conventional sheet pallet is based on a sheet formed by extrusion molding of a thermoplastic resin or the like. Then, on one or both sides, a layer made of an appropriate material has been proposed for the purpose of improving abrasion resistance or sliding a loaded load. (See, for example, JP-A-7-257576 and JP-A-2000-289995.)

[0005] While the conventional sheet pallets are based on thermoplastic resin formed into a sheet, the weight of the sheet pallets is reduced in order to take advantage of the above-mentioned advantages. The mechanical strength that can withstand repeated use is reduced. Disclosure of the invention

[0006] An object of the present invention is to provide a sheet knot which is lightweight and has sufficient mechanical strength to withstand repeated use.

[0007] In order to achieve the above object, a sheet pallet of the present invention is a sheet pallet in which a tab portion integrally extends from a sheet-like portion on which a load is loaded, and is made of thermoplastic resin and extended in one direction. A base material layer in which a plurality of stretched bodies are combined so that the stretching directions are orthogonal to each other; at least one surface layer provided on one surface of the base material layer and constituting a load loading surface; It is formed by a laminated sheet body including at least one back surface layer provided on the other surface.

[0008] As described above, the sheet pallet of the present invention is formed with a laminated sheet body in which a front surface layer and a back surface layer are laminated on both surfaces of a base material layer. Here, since the base material layer is formed by combining a plurality of stretched bodies made of a thermoplastic resin and stretched in one direction so that the stretching directions are orthogonal to each other, the base layer has high tensile strength while being lightweight. As a result, a sheet pallet that can sufficiently withstand repeated use can be obtained. Further, by appropriately combining the materials of the surface layer and the back surface layer, the friction coefficient between the front surface and the back surface can be arbitrarily adjusted, and a sheet pallet having excellent recyclability can be obtained.

[0009] At least a portion of the tab portion may be formed by folding a part of the laminated sheet body and bonding the overlapping facing surfaces to each other. As a result, the rigidity of the tab portion is increased, and the tab portion can be prevented from being bent or damaged during cargo handling.

Brief Description of Drawings

FIG. 1 is a perspective view of a sheet pallet according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of the sheet pallet shown in FIG. 1.

FIG. 3 is a plan view of the reinforcing mesh layer shown in FIG. 2.

FIG. 4A is a partial perspective view of the uniaxially stretched split fiber film shown in FIG. 3.

FIG. 4B is an enlarged view of the uniaxially stretched split fiber film shown in FIG. 4A.

FIG. 5 is a partial perspective view of a raw film used for producing the uniaxially stretched split fiber film shown in FIG. 4, in a state where slits are formed. FIG. 6A is a partial perspective view of a uniaxially stretched slit film applicable to the present invention.

FIG. 6B is an enlarged view of the uniaxially stretched slit film shown in FIG. 6A.

FIG. 7 is a plan view of a nonwoven fabric which is another example of a network structure applicable to the present invention.

FIG. 8 is a plan view of a woven fabric that is still another example of the network structure applicable to the present invention.

FIG. 9 is a perspective view of a base layer made of a nonwoven fabric made of a drawn yarn, which is applicable to the present invention.

FIG. 10 is a plan view of a base material layer which can be applied to the present invention and has a draw yarn force and a woven fabric force.

FIG. 11 is a perspective view of a base layer composed of a uniaxially stretched reticulated film and a uniaxially stretched multilayer tape applicable to the present invention.

FIG. 12 is a perspective view of a base layer composed of a uniaxially stretched reticulated film and a stretched yarn, applicable to the present invention.

FIG. 13 is a diagram illustrating an example of a method for manufacturing a sheet pallet of the present invention by an extrusion lamination method.

FIG. 14 is a perspective view of a sheet pallet according to another embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

[0011] Referring to FIG. 1, a sheet pallet 1 according to an embodiment of the present invention, having a preferably square plate-shaped sheet portion la and a tab portion lb with which one side of the sheet portion la also extends integrally. Is shown. The sheet portion la is a portion on which a load is loaded. The tab portion lb is a portion that is gripped by the push-pull attachment mounted on the forklift when the sheet pallet 1 on which the load is loaded is handled by the forklift. Fig. 1 shows an example in which the tab portion lb extends only on one side of the sheet portion la.The force from each of a plurality of sides such as two opposing sides, two adjacent sides, or three sides of the sheet portion la is shown. The tab part lb is extended.

When handling a sheet pallet 1 loaded with a load, first, a tab lb is gripped by a push-pull attachment mounted on a forklift, and in this state, the pushable attachment is pulled toward the base of the platen of the forklift. As a result, the tab lb is pulled, and the sheet pallet 1 moves while sliding on the platen. And the load is loaded Move the forklift to the desired location with the sheet pallet 1 placed on the platen, and push back the push-pull attachment. As a result, the sheet pallet 1 is lowered on the platen.

[0013] As described above, a very large tensile force is applied to the tab portion lb during the cargo handling operation using the sheet pallet 1. This pulling force is applied repeatedly each time the sheet pallet 1 is used. Therefore, in the present embodiment, the structure described below is employed in order to withstand the tensile force applied repeatedly.

As shown in FIG. 2, the sheet pallet 1 has a reinforcing mesh layer 2, a surface layer 3 stacked on one surface of the reinforcing mesh layer 2, and a sheet layer 1 stacked on the other surface of the reinforcing mesh layer 2. And a back surface layer 4. The surface layer 3 is the side on which the load of the sheet pallet 1 is loaded, and the back layer 4 is the side that contacts the floor surface or the platen of a forklift during use. The sheet pallet 1 also has a laminated sheet strength composed of the reinforced mesh layer 2, the surface layer 3, and the back layer 4. Therefore, the deviation between the sheet-like portion la and the tab portion lb shown in FIG. 1 has the same laminated structure.

[0015] The reinforcing mesh layer 2 has a small thickness and also provides a necessary strength to the sheet pallet 1 and can be made, for example, from a uniaxially stretched mesh film that is stretched in one direction and has a mesh structure. . FIG. 3 shows a plan view of the reinforcing mesh layer 2. As shown in FIG. 3, the reinforced network layer 2 is formed by laminating two uniaxially stretched split fiber films 21 as an example of a uniaxially stretched network film by heat fusion.

[0016] As shown in FIG. 4B, the uniaxially stretched split fiber film 21 has a second thermoplastic resin having a lower melting point than the first thermoplastic resin on both surfaces of a layer 21a made of the first thermoplastic resin. As shown in FIG. 4A, a plurality of trunk fibers 22 extending in parallel with each other and a plurality of It is composed of branch fibers 23 connecting the fibers 22 to each other. The mechanical strength of the uniaxially stretched split fiber film 21, in which the branch fibers 23 are narrower than the trunk fibers 22, is mainly provided by the trunk fibers 22.

[0017] The thickness of the layer 21b made of the second thermoplastic resin is 50% or less, preferably 40% or less, of the entire thickness of the uniaxially stretched split fiber film 21. In order to satisfy various physical properties such as the adhesive strength at the time of heat fusion between the uniaxially stretched split fiber films 21, the thickness of the second thermoplastic resin layer 21b may be 5 μm or more. , Preferably from the range of 10-100 μm Selected.

As a method for producing the uniaxially stretched split fiber film 21, for example, the following method can be mentioned.

First, a layer 2 lb of the second thermoplastic resin is laminated on both surfaces of the first layer 21 a of the thermoplastic resin by extrusion molding such as a multilayer inflation method or a multilayer T-die method. Produce a three-layer raw film. Next, as shown in FIG. 5, the raw film 20 is stretched in the longitudinal direction (L direction), and the stretched raw film 20 is split with a splitter. To form a large number of parallel slits 20a in a zigzag pattern in the vertical direction. Then, the raw film 20 having the slits 20a formed thereon is widened in a direction orthogonal to the direction of the slits 20a. Thereby, as shown in FIG. 4A, a uniaxially stretched split fiber film 21 in which trunk fibers 22 are arranged in a substantially vertical direction is obtained.

The stretching ratio (orientation ratio) is preferably 1.1 to 15 times, more preferably 3 to 10 times.

If the stretching ratio is less than 1.1, the mechanical strength may not be sufficient. On the other hand, if the elongation ratio exceeds 15 times, there arise problems such as the necessity of an expensive apparatus which makes it difficult to perform elongation by a normal method. Stretching is preferably performed in multiple steps to prevent stretching unevenness.

Finally, two uniaxially stretched split fiber films 21 obtained as described above are overlapped with each other so that the stretching directions are orthogonal to each other, and the two are heated and fused to each other, as shown in FIG. As a result, a reinforced mesh layer 2 is obtained. At the time of heat fusion, the superposed uniaxially stretched split fiber film 21 is supplied between a pair of heating cylinders arranged opposite to each other, and is fixed so as not to cause shrinkage in the width direction, and the first heat is also applied to the first heat cylinder. In order not to lose the stretching effect of the layer 21a made of the thermoplastic resin, heat fusion is performed at a temperature lower than the melting point of the first thermoplastic resin and higher than the melting point of the second thermoplastic resin.

[0022] The thickness of the reinforcing mesh layer 2 is preferably from 100 m to 300 µm. More preferably, it is 150 m-250 μm. Since the uniaxially stretched split fiber film 21 constituting the reinforced mesh layer 2 is stretched in one direction, it has sufficient strength even with such a thickness.

[0023] The uniaxially stretched split fiber film 21 has a high tensile strength in the stretching direction. Therefore, two uniaxially stretched split fiber films 21 were laminated so that their stretching directions were orthogonal. By using the reinforcing mesh layer 2 for the sheet pallet 1, the sheet pallet 1 has a high tensile strength that can withstand repeated use. Since the reinforcing mesh layer 2 is a net-like structure, the weight is reduced as a result of using less material, and the sheet pallet 1 itself is easy to handle.

[0024] For example, as a typical example of the reinforced mesh layer 2 in which two uniaxially stretched split fiber films 21 are orthogonally laminated, Nisseki Prif (registered trademark), which is a polyethylene split fiber nonwoven fabric manufactured by Nisseki Plast Co., Ltd. Trademark). Among them, EX (T) (grade name) has a thickness of 0.21 mm and a longitudinal tensile strength of 284 NZ5 cm and a transverse tensile strength of 294 NZ5 cm.

[0025] However, since the reinforced mesh layer 2 has a network structure, the reinforced mesh layer 2 alone is not suitable as the sheet pallet 1. Therefore, the sheet pallet 1 has a structure in which the front surface layer 3 and the back surface layer 4 are laminated on both surfaces of the reinforcing mesh layer 2 respectively. The material for the surface layer 3 and the back layer 4 is appropriately selected in consideration of the purpose of use of the sheet pallet 1 and the required performance. Further, the surface layer 3 and the back surface layer 4 may each be a single layer or may be composed of a plurality of layers. For laminating the surface layer 3 and the back layer 4 on the reinforcing mesh layer 2, a lamination method generally used for laminating sheet materials, such as an extrusion lamination method or a thermocompression bonding method, is used. It can be appropriately selected and used depending on the conditions.

FIG. 13 shows an example of a method of manufacturing the sheet pallet 1 in the case of the extrusion lamination method. In FIG. 13, the reinforcing mesh layer 2, the surface layer 3, and the back layer 4 are wound in a roll shape. First, the reinforcing mesh layer 2 and the back layer 4 are supplied between the first pressure roller pair 13 from different directions. A first extruder 11 is provided above the junction between the reinforced mesh layer 2 and the back layer 4, and the T-die 11 a of the extruder 11 connects the first extruder 11 with the reinforced mesh layer 2 and the back layer 4. A binder made of a thermoplastic resin for bonding is supplied between the reinforcing mesh layer 2 and the back layer 4. The supplied binder is sandwiched between the reinforcing mesh layer 2 and the back layer 4 between the first pressure roller pair 13, and a part of the binder permeates the reinforcing mesh layer 2, whereby the reinforcing mesh layer 2 is removed. And the back surface layer 4 are laminated.

[0027] The obtained laminate la is further sent to the second pressure roller pair 14. In the second pressure roller pair 14, the surface layer 3 is supplied to face the reinforcing mesh layer 2 of the laminate la. Above the junction of the laminate la and the surface layer 3, a second extruder 12 is installed. From the T-die 12a of the machine 12, a binder force made of a thermoplastic resin for bonding the laminate la and the surface layer 3 is supplied between the laminate la and the surface layer 3. The supplied binder is sandwiched between the laminate la and the surface layer 3 between the second pressure roller pair 14, and a part of the binder penetrates into the reinforcing mesh layer 2, whereby the laminate la And the surface layer 3 are laminated.

As described above, a continuous laminate lb having a three-layer structure, which is a material of the sheet pallet 1 (see FIG. 1), is obtained. The obtained laminate lb is cut into a desired shape to obtain a sheet pallet 1 as shown in FIG. In FIG. 13, the back surface layer 4 is laminated first, but the surface layer 3 may be laminated first.

Hereinafter, some examples of combinations of the front surface layer 3 and the back surface layer 4 will be described. In the layer structure shown below, the surface layer is described earlier than the reinforcing mesh layer, the back layer is described later, and the order of the layers indicates the lamination order.

(1) Kraft paper ZLD film Z reinforced mesh layer ZLD film Z kraft paper:

In this layer configuration example, kraft paper is used for the front surface layer 3 and the back surface layer 4, respectively, and this is suitable when it is desired to give the sheet pallet 1 stiffness. The LD film (low-density film) is sandwiched between the kraft paper and the reinforcing mesh layer 2 on the front surface layer 3 and the back layer 4, respectively, and is an adhesive layer (binder) between the kraft paper and the reinforcing mesh layer 2. ). If the reinforcing mesh layer 2 is made of a resin suitable for heat fusion, this adhesive layer can be omitted. As the kraft paper, for example, kraft paper having a basis weight of 100 gZm ² can be used. Further, as the LD film, for example, a low-density polyethylene film having a thickness of 10 μm to 20 μm or a linear low-density polyethylene film can be used.

[0031] (2) LD film Z reinforced mesh layer ZLD film Z kraft paper:

In this layer configuration example, an LD film is used for the surface layer 3 and kraft paper is used for the back layer 4. In order to stably load the sheet pallet 1 so that it does not move on the sheet pallet 1 carelessly, it is preferable that the loading surface of the load has a high friction coefficient. On the other hand, since the back surface of the sheet pallet 1 becomes a sliding surface with respect to the floor surface and the platen of the forklift when handled by the forklift, the coefficient of friction is preferably small.

[0032] Therefore, as in this example, the loading surface and the back surface of the sheet pallet 1 are made of materials having different friction coefficients so that the loading surface has a higher friction coefficient, so that the loaded load can be reduced. Pussy Provided is a sheet pallet 1 that can be easily moved to a platen force and a floor force, and easily moved to the floor surface. Also in this example, the LD film in the back layer 4 functions as an adhesive layer between the craft paper and the reinforcing mesh layer.

Further, in this example, the friction coefficient between the loading surface and the back surface is made different by the combination of the LD film and the kraft paper, but in a combination in which the friction coefficient of the loading surface is higher than the friction coefficient of the back surface. If you like, you can combine them with any material! / ヽ.

[0034] (3) LD film ZOPP film ZLD film Z reinforced mesh layer ZLD film ZOPP film:

In this layer configuration example, the back layer 4 has a configuration in which an OPP film is laminated on the reinforced mesh layer 2 via an LD film functioning as an adhesive layer, and the surface layer 3 has an LD film on top of this layer configuration. Are laminated. The OPP film is a biaxially stretched polypropylene film, for example, a film having a thickness of 20-50 / zm can be used. The coefficient of friction of the LD film is higher than the coefficient of friction of the OPP film. As in the case of the layer configuration (2), the placed load is less likely to slip and the floor force is transferred to the platen and the platen force is applied to the floor. A sheet pallet 1 is provided that can easily be moved. Furthermore, in the present layer configuration example, if the LD film and the reinforced mesh layer 2 are made of a polypropylene-based resin, the recyclability will be excellent.

(4) OPP film ZLD film Z reinforced mesh layer ZLD film ZOPP film:

Also in this layer configuration example, since the OPP film is used for the front layer 3 and the back layer 4, if a polypropylene resin is used for the other layers, the sheet pallet 1 having excellent recyclability can be obtained. In addition, since this layer configuration has a simpler laminated structure as compared with the layer configuration example (3), the manufacturing process is simplified, and as a result, the sheet pallet 1 can be manufactured at low cost.

(5) LD film Z reinforced mesh layer ZLD film ZOPP film:

This layer configuration example is a further simplified layer configuration than the layer configuration example (4).

As described above, the force exemplifying some typical layer configurations of the sheet pallet 1 In the present invention, the front surface layer 3 and the back surface layer 4 may have various other combinations.

[0038] The surface layer 3 and the back layer 4 can each be made of a craft paper resin film, as can be seen from the above-mentioned layer configuration example, and therefore the thickness is also 10 μm-150 mm. μm It may be thin. Therefore, the thickness of the entire sheet pallet 1 is also about 250 m to 550 m. Therefore, according to the present invention, the sheet pallet 1 which is lightweight and has excellent mechanical strength is provided. In addition, since the front surface layer 3 and the back surface layer 4 are made of a kraft paper resin film, they are resistant to moisture and moisture, have excellent durability, and are sanitary without fungus and germs breeding. In particular, when the front surface layer 3 and the back surface layer 4 are made of a resin film, paper dust is not generated and water washing is possible.

FIG. 3 also shows an example in which a uniaxially stretched split fiber film 21 stretched in the longitudinal direction is laminated as a base layer of a sheet pallet in a weft manner. A structure can be used. In the following example, as described above, the constituent materials of the surface layer and the back layer can be appropriately applied in consideration of the purpose of use of the sheet pallet, required performance, and the like.

FIG. 6A shows a partial perspective view of a uniaxially stretched slit film 25 which is another example of the uniaxially stretched mesh film that can be used for the reinforcing mesh layer 2. The uniaxially stretched slit film 25 can be made from the same raw film force used to manufacture the uniaxially stretched split fiber film 21 shown in FIG. 4A. That is, as shown in FIG.6B, the uniaxially stretched slit film 25 has a layer 25a made of a first thermoplastic resin, and a second thermoplastic resin laminated on both surfaces and having a lower melting point than the first thermoplastic resin. And a layer 25b made of thermoplastic resin. Then, the raw film having the layer structure is split or slit in a staggered manner in the horizontal direction (the direction of the arrow T shown in FIG. 6A), stretched in the horizontal direction, and then opened in the vertical direction. As a result, a uniaxially stretched slit film 25 having a network structure and high tensile strength mainly in the transverse direction can be obtained.

[0041] The obtained uniaxially stretched slit film 25 is laminated and thermally fused so that the stretching directions are orthogonal to each other, whereby the reinforced mesh layer 2 can be formed. Alternatively, it is reinforced by combining with the uniaxially stretched split fiber film 21 shown in FIG. 4A and superimposing the uniaxially stretched split fiber film 21 and the uniaxially stretched slit film 25 so that the stretching directions are orthogonal to each other, and heat-sealing. Reticulated layer 2 can be configured.

[0042] The resin constituting the uniaxially stretched split fiber film 21 and the uniaxially stretched slit film 25 includes, for example, polyolefins such as polyethylene and polypropylene, copolymers thereof, and polyolefins. Polyesters such as ethylene terephthalate and polybutylene terephthalate and copolymers thereof; polyamides such as nylon 6 and nylon 66 and copolymers thereof; polymers and copolymers of polychlorinated vinyl, methacrylic acid or derivatives thereof. Coalesced, polystyrene, polysulfone, polytetrachloroethylene polycarbonate, polyurethane and the like. Among them, polyolefin and its polymer, polyester and its polymer, which have good splitting properties, are preferable. Further, the difference in melting point between the first thermoplastic resin and the second thermoplastic resin needs to be 5 ° C or more, preferably 10-50 ° C, for manufacturing reasons. is there.

[0043] As described above, an example in which the two reinforced films are formed by laminating two films each formed in a net shape has been described. However, as a base material layer, other than the above, as shown in FIGS. 7 and 8, Alternatively, a nonwoven fabric 27 or a woven fabric 29 made of a uniaxially stretched multilayer tape 28 can be used. Each of the non-woven fabric 27 and the woven fabric 29 is 1.1 to 15 times, preferably 3 to 10 times the same raw film as used for manufacturing the uniaxially stretched split fiber film 21 shown in FIG. 4A. It is made of a uniaxially stretched multilayer tape 28 which is uniaxially stretched and then cut along a stretching direction at a width of 2 mm to 7 mm. The cutting of the raw film may be performed before stretching. The nonwoven fabric 27 shown in FIG. 7 is made by arranging a plurality of uniaxially stretched multilayer tapes 28 in parallel at regular intervals and laminating them in two layers so that the longitudinal direction of the uniaxially stretched multilayer tapes 28 is orthogonal. is there. The woven fabric 29 shown in FIG. 8 is obtained by weaving the uniaxially stretched multilayer tape 28 vertically and horizontally.

[0044] The base layer may be made of a reinforced mesh layer made of the above-described uniaxially stretched mesh film, a woven fabric or a nonwoven fabric made of a uniaxially stretched multilayer tape, or a thermoplastic resin such as polyethylene or polypropylene. Spun drawn yarns can also be used. Fig. 9 shows a nonwoven fabric substrate in which a plurality of stretched yarns 41 are arranged in parallel at regular intervals and are laminated in two layers so that the stretched direction (longitudinal direction) of the stretched yarns 41 is orthogonal. Layers are shown. FIG. 10 shows a base layer having a woven fabric strength in which a plurality of drawn yarns 41 are woven so that the drawing directions are orthogonal to each other.

[0045] Further, the base material layer may be constituted by appropriately combining the above-described uniaxially stretched reticulated film, uniaxially stretched multilayer tape, and stretched yarn. For example, in the base layer shown in FIG. 11, the stretching direction of the uniaxially stretched reticulated film 51 and the plurality of uniaxially stretched multilayer tapes 28 are orthogonal. The base material layer shown in FIG. 12 also has a laminate force obtained by laminating the uniaxially stretched reticulated film 51 and the plurality of stretched yarns 41 so that the stretching directions are orthogonal to each other.

FIG. 14 is a perspective view of a sheet pallet according to another embodiment of the present invention. The basic structure of the sheet pallet 31 shown in Fig. 14 is the same as that shown in Fig. 1, and a sheet portion 3 la for loading a load and a tab portion 3 lb extending integrally from the sheet portion 3 la are provided. Having. Further, a laminated sheet body as a material of the sheet pallet 31 is configured similarly to the above-described embodiment. This embodiment is different from the above-described embodiment in that the tab portion 31b is double.

[0047] By making the tab portion 31b double, the rigidity of the tab portion 31b is increased. As a result, it is possible to prevent the tab portion 31b from being bent or damaged during the cargo handling operation using the forklift.

[0048] The double tab portion 31b can be formed, for example, as follows. First, when cutting the laminated sheet body to be the material of the sheet pallet 31, the dimensions of the portion to be the tab 31b are determined by the extension length L of the target tab portion 31b (the sheet in the direction perpendicular to the width direction). (Length from the boundary with the section 31a to the tip)). Then, a portion extended with respect to the target dimension of the tab portion 31b is folded back to the sheet portion 31a side by 180 °, and the overlapping surfaces are bonded to each other. This bonding can be performed by heat fusion and ultrasonic bonding if the surface that becomes inside when folded is a thermoplastic resin. Also, if an adhesive is used, even if the overlapping surfaces are kraft paper, they can be bonded.

[0049] Further, the sheet pallet 31 can be obtained by processing both sides into a tapered shape as needed, or bending the tab portion 31b so as to be inclined upward with respect to the sheet portion 31a. . The 3 lb tapered tab portion after the extended portion is folded back and bonded can be saved by cutting in advance into the shape considering the final 3 lb shape when cutting the laminated sheet body. Can be abbreviated. Also, inclining the tab 31b with respect to the seat 31a makes it easier to grasp the tab 3lb with the gripper of the push-pull attachment or to lift it up onto the platen when carrying out cargo handling work by forklift. To do so, the sheet pallet 31 is generally used.

As to the direction in which the laminated sheet body is folded, FIG. 14 shows an example in which the laminated sheet body is folded back to the loading surface side of the load. However, it may be folded in the opposite direction, that is, to the back side of the sheet pallet 31. However, depending on the inclination angle of the tab part 31b with respect to the seat part 31a and the thickness of the sheet pallet 31, if the folded back is located on the back side, it may interfere with the cargo handling work with a forklift. If this is a concern, the turn-back should be on the loading surface side.

In the example shown in FIG. 14, the entire tab portion 31b has a double force. If at least the portion requiring rigidity is double, the entire portion need not be double. The portion requiring rigidity is, for example, a portion where the platen of the forklift enters during loading and unloading and is likely to be bent or damaged.

[0052] The tab portion 31b may be reinforced by folding the sheet pallet 31 into three or more layers within a range that does not impair the lightness of the sheet pallet 31. When the tab portion 31b is folded three or more times, any method can be applied, such as a method of folding the extended portion so as to wind it in, or a method of folding in a zigzag shape. .

Hereinafter, specific examples of the present invention will be described together with comparative examples.

(Example 1)

In this example, a sheet pallet was manufactured according to the above-described layer configuration example (1). The base layer is made of Nisseki Prif (registered trademark), a polyethylene split fiber non-woven fabric manufactured by Nisseki Plast Co., Ltd., grade I (II) (hereinafter referred to as “II Riff II (Τ)”). Was used.ヮ rif ヮ (Τ) had a basis weight of S49 gZm ² and a thickness of 0.21 mm. Then, on both sides of Warifu EX (T), as a front surface layer and the back layer, the basis weight is laminated by an extrusion Ramineshiyon method through a low density polyethylene film m thick respectively kraft paper LOOgZm ^2, resulting A sheet pallet was prepared for the physical strength of the laminated sheet.

(Example 2)

In this example, a sheet pallet was manufactured according to the above-described layer configuration example (3). As a substrate layer, as in Example 1, Perif EX (T) was used. The surface layer has a two-layer structure of a biaxially stretched polypropylene film of 20 / zm thickness and a low-density polyethylene film of 15 μm thickness, and the polyethylene film is a 15 μm-thick low-density polyethylene film with the ヮ rif EX (T) side. It was laminated on one side of Perif EX (T) via a film. The back layer is a biaxially oriented polypropylene film with a thickness of 20 m, and a ヮ rif EX (T) Laminated on the other side. These laminations were performed by an extrusion lamination method. A sheet pallet was also prepared with the laminated sheet thus obtained.

(Comparative Example 1)

Sheet pallets were made by extrusion of polypropylene.

(Comparative Example 2)

Sheet pallets were made of paper.

The thickness, the tensile strength in the longitudinal direction, and the tensile strength in the lateral direction were measured for Examples 1 and 2 and Comparative Examples 1 and 2 produced as described above. Table 1 shows the measurement results.

[Table 1]

Table 1 shows that Example 1 has a higher tensile strength and a lighter weight per unit area than Comparative Examples 1 and 2. Further, Example 2 has a tensile strength equal to or higher than Comparative Examples 1 and 2, and in particular, the weight per unit area is significantly lighter and the thickness is thinner.

Claims

The scope of the claims

[1] A sheet pallet in which a tab portion integrally extends from a sheet-like portion on which a load is to be loaded, wherein a plurality of stretched bodies made of thermoplastic resin and stretched in one direction are arranged so that the stretching directions are orthogonal to each other. A substrate layer provided on one surface of the base material layer, at least one surface layer constituting the loading surface of the load, and at least one surface layer provided on the other surface of the base material layer. A sheet pallet formed of a laminated sheet body including one back layer.

[2] The base material layer has a layer made of a second thermoplastic resin having a melting point lower than that of the first thermoplastic resin laminated on both surfaces of a layer made of the first thermoplastic resin. 2. The sheet pallet according to claim 1, wherein the sheet pallet is a nonwoven fabric formed by laminating a plurality of uniaxially stretched net-like films made from an original film so that stretching directions are orthogonal to each other.

[3] The base material layer has a layer made of a second thermoplastic resin having a melting point lower than that of the first thermoplastic resin laminated on both surfaces of a layer made of the first thermoplastic resin. 2. The sheet pallet according to claim 1, wherein the sheet pallet is a woven fabric formed by weaving a plurality of uniaxially stretched tapes from an original film so that stretching directions are orthogonal to each other.

[4] In the base material layer, a layer made of a second thermoplastic resin having a melting point lower than that of the first thermoplastic resin is laminated on both surfaces of a layer made of the first thermoplastic resin. 2. The sheet pallet according to claim 1, wherein the sheet pallet is a woven fabric formed by weaving a plurality of uniaxially drawn yarns from an original film so that the drawing directions are orthogonal to each other.

[5] The base material layer includes a layer made of a second thermoplastic resin having a melting point lower than that of the first thermoplastic resin laminated on both surfaces of a layer made of the first thermoplastic resin. 2. The sheet pallet according to claim 1, wherein the sheet pallet is a nonwoven fabric formed by laminating a plurality of uniaxially stretched tapes from an original film so that stretching directions are orthogonal to each other.

[6] In the base material layer, a layer made of a second thermoplastic resin having a melting point lower than that of the first thermoplastic resin is laminated on both surfaces of a layer made of the first thermoplastic resin. 2. The sheet pallet according to claim 1, wherein the sheet pallet is a nonwoven fabric formed by laminating a plurality of uniaxially drawn yarns from an original film so that the drawing directions are orthogonal to each other.

[7] In the base material layer, a layer made of a second thermoplastic resin having a melting point lower than that of the first thermoplastic resin is laminated on both surfaces of a layer made of the first thermoplastic resin. From the original film 2. The sheet pallet according to claim 1, wherein the sheet pallet is a laminate obtained by laminating a uniaxially stretched reticulated film and a plurality of uniaxially stretched tapes so that stretching directions are orthogonal to each other.

[8] In the base material layer, a layer made of a second thermoplastic resin having a melting point lower than that of the first thermoplastic resin is laminated on both surfaces of a layer made of the first thermoplastic resin. 2. The sheet pallet according to claim 1, wherein the sheet pallet is a laminate formed by laminating a uniaxially stretched net-like film and a plurality of uniaxially stretched yarns so that the stretching directions are orthogonal to each other.

[9] The sheet pallet according to claim 1, wherein the front surface layer and the back surface layer include kraft paper.

[10] The sheet pallet according to claim 1, wherein the front surface layer has a low density film, and the back surface layer has kraft paper.

11. The sheet pallet according to claim 1, wherein the surface layer has a low-density film, and the back surface layer has a biaxially oriented polypropylene film.

[12] The base layer and the low-density film are made of a polypropylene resin.

The sheet pallet according to 1.

13. The sheet pallet according to claim 1, wherein the front surface layer and the back surface layer have a biaxially stretched polypropylene film, and the base layer is made of a polypropylene resin.

[14] The sheet pallet according to claim 1, wherein the overall thickness is 250 µm-550 µm.

[15] The sheet pallet according to claim 1, wherein at least a part of the tab portion is formed by folding a part of the laminated sheet body and bonding the opposing surfaces overlapping each other. .