Paper structure, paper tray and method of manufacturing same

Abstract

To propose a paper tray which comprises a tray body and a liner material and which has good moldability of a body, makes the liner material less likely to be lifted, and has one flat flange part to achieve good sealability of a lid member.SOLUTION: A paper structure (BLKS) has one rectangular-frame-like flange part 4. In the paper structure (BLKS), a tray-like paper base 2 comprising the flange part, a top panel 5, an end panel 7, a left side panel 11, a right side panel 21, and a bottom surface is formed by molding. The top panel and a bottom panel A (6) are connected to the inner side of an upper side of the flange part and an end panel and a bottom panel B (8) are connected to the inner side of a lower side of the flange part. The bottom panel A and the bottom panel B are connected through a cuttable perforated line 9.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a paper tray, and to a paper structure from which a paper tray can be easily formed, a paper tray made therefrom, and a method for manufacturing the paper tray. [Background technology]

[0002] As tray-shaped containers, various types of paper and plastic containers have been put to practical use in the past. When it is desired to seal the contents, plastic containers having flat flanges have been generally used so that a lid can be easily sealed.

[0003] However, in recent years, due to environmental concerns, containers made from paper, a renewable resource, have begun to attract attention rather than plastic containers made from limited petroleum resources, and paper trays that combine a paper base with a plastic liner have been proposed.

[0004] However, in conventional paper trays in which the paper base and plastic liner can be separated, the paperboard structure forming the flange is generally separated, and since the flange has a step, it is difficult to completely seal the lid. Therefore, there is an increasing demand for a paper tray in which the flange does not have a step, and therefore the lid can be hermetically sealed.

[0005] The paper container described in Patent Document 1 was created against this background, and is characterized in that it comprises a paper container body assembled from a blank made primarily of paper, in which a reinforcing surface, side surface, and bottom half surface are connected sequentially to the outer edges of a pair of opposing frames of a rectangular frame-shaped flange portion via fold lines, the side surfaces are connected to the inner edges of another pair of opposing frames via fold lines, and the reinforcing surfaces are connected to the outer edges via fold lines, and an internal protective film layer made of thermoplastic resin that is tightly adhered to the inner surface of the paper container body by being sucked by vacuum or compressed air in a heated state.

[0006] The paper container described in Patent Document 1 has a flange formed from a single continuous paper base material, which is advantageous for the sealing of the lid material, but the side of the container is structured with a front and back paper, which makes the molding process complicated and raises concerns that it may get caught during molding, resulting in a high reject rate. Also, because there is no overlap of panels on the bottom surface, there is an issue that the liner material may float when the tray is bent. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Patent No. 4305981 Summary of the Invention [Problem to be solved by the invention]

[0008] The problem that the present invention aims to solve is to propose a paper tray composed of a paper tray body and a liner material, in which the paper body has good formability, the liner material is less likely to float, and the lid material has good sealing properties due to the presence of a continuous flat flange portion. [Means for solving the problem]

[0009] As a means for solving the above problem, the invention described in claim 1 is a paper structure having a flange portion in the shape of a continuous rectangular frame consisting of an upper side, a lower side, a left side, and a right side, and by molding, a tray-shaped paper base consisting of the flange portion, a top panel, an end panel, a left side panel, a right side panel, and a bottom, wherein the top panel and the bottom panel A are connected to the inside of the upper side of the flange portion via fold lines, and the end panel and the bottom panel B are connected to the inside of the lower side of the flange portion via fold lines, and the bottom panel A and the bottom panel B are connected to each other via a cuttable perforation line, and a left glue tab is bonded to the back surface of the left side of the flange portion, connecting the left side panel and the bottom panel C via the fold lines, and a right glue tab is bonded to the back surface of the right side of the flange portion, connecting the right side panel and the bottom panel D via the fold lines.

[0010] In the paper structure of the present invention, the opposing bottom panels A and B are connected via a cuttable perforation line, so that the paper structure will not bend or overlap during transportation or molding, and stable moldability can be expected.

[0011] The invention described in claim 2 is a paper tray composed of a paper base formed from a paper structure and a thermoplastic resin liner material, the paper structure having a flange portion in the shape of a continuous rectangular frame consisting of an upper side, a lower side, a left side, and a right side, a top panel and a bottom panel A are connected to the inside of the upper side of the flange portion via a fold line, an end panel and a bottom panel B are connected to the inside of the lower side of the flange portion via a fold line, the bottom panels A and B are connected to each other via a cuttable perforation line, a left glue tab is attached to the back surface of the left side of the flange portion, connecting the left side panel and the bottom panel C via the fold line, and a right glue tab is attached to the back surface of the right side of the flange portion, connecting the right side panel and the bottom panel D via the fold line, and when the paper structure is formed into a tray shape, the perforation line is cut and the bottom panels A and B are separated.

[0012] The invention described in claim 3 is a paper tray composed of a paper base formed by molding a paper structure and a thermoplastic resin liner material, the paper structure having a flange portion in the shape of a continuous rectangular frame consisting of upper, lower, left and right sides, a top panel and a bottom panel A are connected to the inside of the upper side of the flange portion via respective fold lines, an end panel and a bottom panel B are connected to the inside of the lower side of the flange portion via respective fold lines, and the bottom panels A and B are cuttable. The left and right sides of the flange are connected via a perforation line, and a left glue tab is adhered to the back surface of the left edge of the flange, connecting the left side panel and the bottom panel C via a fold line, and a right glue tab is adhered to the back surface of the right edge of the flange, connecting the right side panel and the bottom panel D via a fold line.When the paper structure is molded into a tray shape, the perforation line is cut and the bottom panels A and B are separated, and the bottom panels C and D have an overlapping portion.This is a paper tray characterized in that:

[0013] The invention described in claim 4 is the paper tray described in claim 2 or 3, characterized in that the thermoplastic resin liner material has a gas barrier layer.

[0014] The invention described in claim 5 is a method for manufacturing a paper tray described in any one of claims 2 to 4, characterized in that the paper structure described in claim 1 is placed on a receiving mold of a molding machine, a mold is pressed from above to cut the perforation line of the paper structure, and the paper structure is molded into a tray shape, and then a vacuum forming machine or a vacuum pressure forming machine is used to cover and adhere a thermoplastic resin liner material to the inner surface of the tray.

[0015] The invention described in claim 6 is the method for manufacturing a paper tray described in claim 5, characterized in that the forming machine also serves as a vacuum forming machine or a vacuum / pressure forming machine. Effect of the Invention

[0016] In the paper structure of the present invention described in claim 1, the opposing bottom panels A and B are connected via a cuttable perforation line, and are cut only when the structure is molded, so the structure does not bend or overlap during transportation or molding, and is excellent in transport suitability and transport efficiency. In addition, because the structure exhibits stable moldability, it is possible to build a stable logistics and filling line even if the factory where the paper structures are manufactured is different from the factory where the paper structures are molded, paper trays are assembled, and the contents are filled in.

[0017] The paper tray of the present invention has a structure in which a thermoplastic resin liner material is integrally attached to a paper base, so that the paper base and the liner material can be easily separated after use, making it highly efficient for recycling.

[0018] The paper tray according to the present invention has a flat flange portion that is continuous and has no steps, so that the paper tray has excellent sealing properties for the lid material and can stably seal the lid.

[0019] When the bottom panels which are extensions of the side panels are overlapped with each other as in the paper tray described in claim 3, this has the effect of preventing the thermoplastic resin liner material from floating up.

[0020] When the thermoplastic resin liner material has a gas barrier layer as in the invention described in claim 4, it becomes possible to store food and the like and achieve long-term preservation.

[0021] The paper tray of the present invention can be easily formed using a general forming machine or a vacuum / compressed air forming machine, etc., so even food manufacturers and other entities with no experience in producing traditional paper containers can easily set up an integrated production line for forming paper trays and filling them with contents. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic plan view showing one embodiment of a paper tray according to the present invention. [Diagram 2]FIG. 2 is a schematic cross-sectional view showing the AA′ cross section of FIG. [Diagram 3] FIG. 3 is a schematic plan view showing a paper base blank that is the basis of the paper structure according to the present invention, in which the left and right side panels and the bottom panel are not yet bonded. [Figure 4] FIG. 4 is a schematic plan view showing one embodiment of the paper structure according to the present invention. [Diagram 5] FIG. 5 is an explanatory cross-sectional view showing how the paper structure is pressed by the receiving die and the pressing die of the molding machine to form the paper base. [Figure 6] FIG. 6 shows the state in which the paper structure is molded by the molding machine to form the completed paper base. [Figure 7] FIG. 7 is a cross-sectional explanatory view showing the process of adhering a thermoplastic resin liner material to a molded paper base by using a vacuum / compressed air molding machine. [Figure 8] FIG. 8 is a cross-sectional explanatory view showing a process in which the upper chamber of the vacuum and pressure molding machine is closed and the thermoplastic resin liner material is heated and softened. [Figure 9] FIG. 9 is an explanatory cross-sectional view showing a process of adhering a thermoplastic resin liner material to a paper base by applying compressed air to an upper chamber of a vacuum and pressure forming machine and suctioning a lower chamber by vacuum. [Figure 10] FIG. 10 is a schematic cross-sectional view showing an example of a cross-sectional configuration of a thermoplastic resin liner material. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] The paper tray according to the present invention, the paper structure for forming the paper tray, and the method for manufacturing the paper tray will be described in detail below with reference to the drawings. Fig. 1 is a schematic plan view showing one embodiment of the paper tray according to the present invention. Fig. 2 is a schematic cross-sectional view showing the AA' cross section of Fig. 1. Fig. 3 is a schematic plan view showing a paper base blank that is the basis of the paper structure according to the present invention, showing a state in which the left and right side panels and the bottom panel are not bonded. Fig. 4 is a schematic plan view showing one embodiment of the paper structure according to the present invention.

[0024] The paper structure (BLKS) of the present invention, as described in the claims, is a paper structure (blank) that has a continuous rectangular frame-shaped flange portion (4) consisting of an upper side (4A), a lower side (4B), a left side (4C), and a right side (4D), and is molded to form a tray-shaped paper base (2) consisting of the flange portion (4), a top panel (5), an end panel (7), a left side panel (11), a right side panel (21), and a bottom surface.

[0025] A top panel (5) and a bottom panel A (6) are connected to the inside of the upper side (4A) of the flange portion (4) via fold lines (a) and (b), respectively, and an end panel (7) and a bottom panel B (8) are connected to the inside of the lower side (4B) of the flange portion (4) via fold lines (c) and (d), respectively. The bottom panel A (6) and the bottom panel B (8) are connected to each other via a cuttable perforation line (9).

[0026] A left glue tab (10) is adhered to the back surface of the left side (4C) of the flange portion (4), connecting the left side panel (11) and the bottom panel C (12) via fold lines (e) and (f). A right glue tab (20) is adhered to the back surface of the right side (4D) of the flange portion (4), connecting the right side panel (21) and the bottom panel D (22) via fold lines (g) and (h).

[0027] Next, the paper base (2) that is the basis of the paper tray (1) obtained by molding this paper structure (BLKS) will be described. Fig. 1 is a schematic plan view showing one embodiment of the paper tray (1) according to the present invention, but for ease of understanding, the thermoplastic resin liner material (3) is omitted in this drawing as it is transparent and invisible. Therefore, Fig. 1 can also be seen as a drawing showing the paper base (2).

[0028] FIG. 2, which is a cross-sectional view taken along the line AA′ of FIG. 1, shows a thermoplastic resin liner material (3) and a lid material (30) which is finally sealed.

[0029] In the example shown in Figure 1, bottom panel C (12) and bottom panel D (22) form a bottom overlapping portion (13). The length of bottom panel C (12) and the length of bottom panel D (22) may be set to a length that just butts together when molded, but it has been found that the presence of this overlapping portion (13) has the effect of preventing lifting when the thermoplastic resin liner material (3) is adhered.

[0030] Fig. 3 is a schematic plan view showing the paper base blank (BL) that is the basis of the paper structure (BLKS) according to the present invention, showing the state in which the left and right side panels and the bottom panel are not glued. In this figure, when the left glue tab (10) is glued to the back surface of the left side (4C) and the right glue tab (20) is glued to the back surface of the right side (4D), the paper structure (BLKS) shown in Fig. 4 is obtained. In Fig. 4, the fold lines a to h are omitted to avoid complication.

[0031] The paper structure (BLKS) shown in FIG. 4 is made of a receiving mold (41) and a pressing mold (42) as shown in FIG. By molding the paper base (2) using a molding machine (40) equipped with a mold (42), a three-dimensional paper base (2) can be produced extremely easily and stably. Figure 5 is a cross-sectional explanatory diagram showing how the paper base (2) is formed by pressing the paper structure (BLKS) with the receiving mold (41) and the pressing mold (42) of the molding machine (40). Figure 6 shows the completed paper base (2) after the paper structure (BLKS) is molded by the molding machine (40).

[0032] 7 to 9 are cross-sectional explanatory views showing the process of adhering a thermoplastic resin liner material (3) to a completely molded paper base (2) by a vacuum pressure molding machine (50). Fig. 7 is a cross-sectional explanatory view showing the paper base (2) being set in the lower chamber (51) of the vacuum pressure molding machine (50) and the upper chamber (52) being lowered.

[0033] Fig. 8 is a cross-sectional explanatory diagram showing a process in which the upper chamber (52) of the vacuum pressure molding machine (50) is closed and the thermoplastic resin liner material (3) is heated and softened by a heater (53). Next, as shown in Fig. 9, pressurized air (54) is applied to the upper chamber (52) of the vacuum pressure molding machine (50) and the lower chamber (51) is subjected to vacuum suction (55), thereby bonding the thermoplastic resin liner material (3) to the paper base (2).

[0034] In the above explanation, the molding machine (40) that molds the paper base (2) and the vacuum / compressed air molding machine (50) that adheres the thermoplastic resin liner material (3) to the paper base (2) are described as separate devices, but these series of processes can also be performed consistently by a single common device (not shown).

[0035] The materials used for the paper tray (1) according to the present invention will be described. First, the paper base (2) has a basis weight of 100 g / m 2 ~500g / m 2Paperboard of any grade can be used. The paperboard is selected according to the intended use of the paper tray and its printability. Specific examples include manila cardboard, white cardboard, chipboard, double-sided cardboard, white-backed cardboard, ivory paper, carton base paper, cup base paper, coated cardboard, etc. If the application is to store food, food-grade paperboard is preferable.

[0036] As the thermoplastic resin liner material (3), various thermoplastic resin films that can be vacuum-formed can be used. Specifically, synthetic resin films such as low-density polyethylene resin (LDPE), high-density polyethylene resin (HDPE), linear low-density polyethylene resin (LLDPE), polypropylene resin (PP), polyolefin-based resins such as polyolefin-based elastomers, polyester-based resins such as polyethylene terephthalate resin (PET), polybutylene terephthalate resin (PBT), and polyethylene naphthalate resin (PEN), polymethyl methacrylate resin (PMMA), ethylene-vinyl acetate copolymer resin (EVA), polyamide-based resins such as nylon-6 and nylon-66, polyvinyl chloride resin (PVC), and polyvinylidene chloride resin (PVDC) can be used alone or in combination with an adhesive layer.

[0037] Figure 10 is a schematic cross-sectional view showing an example of the cross-sectional configuration of a thermoplastic resin liner material (3). This example is a multilayer film consisting of three layers: a polyolefin resin (3A), a gas barrier layer (3B), and a polyolefin resin (3C). As the polyolefin resin, a polyethylene resin or a polypropylene resin is used. When heating in a microwave oven is expected, a polypropylene resin is used.

[0038] Examples of the gas barrier layer (3B) include gas barrier films such as polyvinylidene chloride (PVDC) films, polyvinyl alcohol (PVA) films, ethylene vinyl alcohol copolymer (EVOH) films, gas barrier nylon films, and gas barrier polyethylene terephthalate (PET) films; metal-deposited films in which metals such as aluminum are deposited on PET films; and inorganic oxides such as aluminum oxide and silicon oxide are deposited on PET films. Examples of the gas barrier coating layer that can be used include an inorganic oxide vapor deposition film in which an inorganic oxide is vapor-deposited by vapor-depositing an inorganic oxide, a polyvinylidene chloride coating, a coating containing a water-soluble resin and an inorganic layered compound, and a resin layer formed by reacting a metal alkoxide or its hydrolysate with an isocyanate compound.

[0039] The lid material (30) is generally printed, and is selected in consideration of printability, sealability, ease of opening, etc. A composite film formed by dry laminating a biaxially oriented film and a sealant film, which have good printability, is preferably used.

[0040] The paper tray according to the present invention will be described in more detail below based on examples and comparative examples. EXAMPLES

[0041] <Example 1> As a paper-based material, food-grade paperboard (OK Frace PRO manufactured by Oji Paper Co., Ltd., basis weight 310 g / m 2 ) was used to create a paper base blank as shown in Figure 3. The overlapping parts were glued with emulsion adhesive (manufactured by Nichiei Kako Co., Ltd.) to create a paper structure with overlapping bottom panels as shown in Figure 4.

[0042] The thermoplastic resin liner material used was a three-layer laminate film of polyethylene resin (20 μm) / EVOH (10 μm) / polyethylene resin (20 μm).

[0043] Using these materials, paper trays as shown in Figures 1 and 2 were created and evaluated for the following items. <Separability> The peelability of the paper base and the liner material was evaluated. Thirty panelists were asked to peel the paper from the liner material, and if 25 or more judged the paper base and liner material to be easy to separate, the paper base and liner material were marked as "good." <Suitability for transporting blanks> 500 paper structures (blanks) were packed in a cardboard box, and the blanks were evaluated for displacement after vibration and drop tests, as well as for the blanks getting caught or stuck. Cases where each could be separated independently were marked as ◯. <Moldability> The yield rate during molding of paper structures (blanks) was evaluated. A value of 95% or higher was rated as ◯. <Float> After forming the paper tray, it was manually bent from the side panel to the inside and the lifting of the liner material was evaluated. Those that did not float were marked with an O. <Sealing performance> Those which could completely seal the lid were rated as ◯.

[0044] <Example 2> The paperboard used was food-grade paperboard (OK Frace PRO, manufactured by Oji Paper Co., Ltd., with a basis weight of 400 g / m 2 A paper tray was prepared in the same manner as in Example 1, except that ), and was evaluated in the same manner.

[0045] <Example 3> A paper tray was prepared in the same manner as in Example 2, except that a three-layer laminated film of polyethylene resin (20 μm) / EVOH (10 μm) / polypropylene resin (20 μm) was used as the thermoplastic resin liner material, and was evaluated in the same manner.

[0046] <Example 4> As the paperboard, food-grade paperboard (APP Alikin Cream, basis weight 250 g / m 2 A paper tray was prepared in the same manner as in Example 3, except that ), and was evaluated in the same manner.

[0047] <Example 5> As the paperboard, food-grade paperboard (APP Alikin Cream, basis weight 250 g / m 2 A paper tray was prepared in the same manner as in Example 1, except that ), and was evaluated in the same manner.

[0048] <Example 6> A paper tray was produced in the same manner and using the same materials as in Example 1, except that no overlapping of the bottom plates was generated at the bottom, and was similarly evaluated.

[0049] <Example 7> A paper tray was produced in the same manner and using the same materials as in Example 2, except that no overlapping of the bottom plates was generated at the bottom, and was similarly evaluated.

[0050] <Example 8> A paper tray was produced in the same manner and using the same materials as in Example 3, except that no overlapping of the bottom plates was generated at the bottom, and was similarly evaluated.

[0051] <Example 9> A paper tray was produced in the same manner and using the same materials as in Example 4, except that no overlapping of the bottom plates was generated at the bottom, and was similarly evaluated.

[0052] <Example 10> A paper tray was produced in the same manner and using the same materials as in Example 5, except that no overlapping of the bottom plates was formed on the bottom surface, and was similarly evaluated.

[0053] <Comparative Example 1> Commercially available paper trays (paperboard basis weight 310 g / m 2 A similar evaluation was carried out using a paper tray (liner material: polyethylene resin 20 μm). This paper tray had a step at the flange.

[0054] <Comparative Example 2> A paper tray was produced in the same manner as in Example 6 using the same materials, except that the perforations were cut in the paper structure (blank) from the beginning, and was similarly evaluated.

[0055] <Comparative Example 3> A paper tray was produced in the same manner as in Example 7 using the same materials, except that the perforations were cut from the beginning in the paper structure (blanks), and was similarly evaluated.

[0056] <Comparative Example 4> A paper tray was produced in the same manner as in Example 8 using the same materials, except that the perforations were cut from the beginning in the paper structure (blanks), and was similarly evaluated.

[0057] <Comparative Example 5> A paper tray was produced in the same manner as in Example 9 using the same materials, except that the perforations were cut from the beginning in the paper structure (blanks), and was similarly evaluated.

[0058] <Comparative Example 6> A paper tray was produced in the same manner as in Example 10 using the same materials as in Example 10, except that the perforations in the paper structure (blank) were cut from the beginning, and was similarly evaluated.

[0059] The above evaluation results are summarized in Table 1.

[0060] [Table 1]

[0061] From the results in Table 1, it was found that in the paper structure, bottom panel A and bottom panel B are connected by a perforation line, which improves the transportability and formability of the blank. It was also found that the overlap of the bottom panels has the effect of preventing floating. [Explanation of symbols]

[0062] 1. Paper tray 2. Paper-based BL...Paper-based blank BLKS: Paper structures (blanks) 3. Thermoplastic resin liner material 3A: Polyolefin resin 3B: Gas barrier layer 3C: Polyolefin resin 4. Flange section 4A...Top 4B... Bottom edge 4C... Left side 4D...Right side 5. Top panel 6 Bottom Panel A 7 End panel 8 Bottom panel B 9. Perforation 10...Left glue allowance 11 Left side panel 12 Bottom Panel C 13 Bottom overlap 20 Right margin 21 Right side panel 22 Bottom panel D a~h... fold lines 30...Lid material 40...Molding machine 41...Mold 42 Press mold 50...Vacuum pressure forming machine 51 Lower chamber 52 Upper chamber 53 Heater 54 Pressurized air 55...Vacuum suction

Claims

1. A paper structure having a flange portion in the shape of a continuous rectangular frame consisting of an upper side, a lower side, a left side, and a right side, and formed to form a tray-shaped paper base consisting of the flange portion, a top panel, an end panel, a left side panel, a right side panel, and a bottom surface, A top panel and a bottom panel A are connected to the inside of the upper side of the flange portion via a fold line, An end panel and a bottom panel B are connected to the inside of the lower side of the flange portion via a fold line, The bottom panel A and the bottom panel B are connected via a cuttable perforation line, A left glue tab is attached to the back surface of the left side of the flange portion, which connects the left side panel and the bottom panel C via a fold line. This paper structure is characterized in that a right glue tab is adhered to the back surface of the right side of the flange portion, connecting the right side panel and the bottom panel D via a fold line.

2. A paper tray comprising a paper base formed by molding a paper structure and a thermoplastic resin liner material, The paper structure has a flange portion in the shape of a continuous rectangular frame having an upper side, a lower side, a left side, and a right side, A top panel and a bottom panel A are connected to the inside of the upper side of the flange portion via a fold line, An end panel and a bottom panel B are connected to the inside of the lower side of the flange portion via a fold line, The bottom panel A and the bottom panel B are connected via a cuttable perforation line, A left glue tab is attached to the back surface of the left side of the flange portion, which connects the left side panel and the bottom panel C via a fold line. A right adhesive tab is attached to the back surface of the right side of the flange portion, which connects the right side panel and the bottom panel D via a fold line. This paper tray is characterized in that when the paper structure is formed into a tray shape, the bottom panel A and the bottom panel B are separated along the perforation line.

3. A paper tray comprising a paper base formed by molding a paper structure and a thermoplastic resin liner material, The paper structure has a flange portion in the shape of a continuous rectangular frame having an upper side, a lower side, a left side, and a right side, A top panel and a bottom panel A are connected to the inside of the upper side of the flange portion via a fold line, An end panel and a bottom panel B are connected to the inside of the lower side of the flange portion via a fold line, The bottom panel A and the bottom panel B are connected via a cuttable perforation line, A left glue tab is attached to the back surface of the left side of the flange portion, which connects the left side panel and the bottom panel C via a fold line. A right adhesive tab is attached to the back surface of the right side of the flange portion, which connects the right side panel and the bottom panel D via a fold line. This paper tray is characterized in that, when the paper structure is formed into a tray shape, the perforation line is cut to separate bottom panel A and bottom panel B, and bottom panel C and bottom panel D have an overlapping portion.

4. 4. The paper tray according to claim 2 or 3, wherein the thermoplastic resin liner material has a gas barrier layer.

5. A method for manufacturing a paper tray according to any one of claims 2 to 4, characterized in that the paper structure according to claim 1 is placed on a receiving mold of a molding machine, a press mold is pressed against it from above to cut the perforation line of the paper structure, and the paper structure is molded into a tray shape, and then a thermoplastic resin liner material is coated and adhered to the inner surface of the tray using a vacuum molding machine or a vacuum pressure molding machine.

6. 6. The method for manufacturing a paper tray according to claim 5, wherein the forming machine also serves as a vacuum forming machine or a vacuum / compressed air forming machine.

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