JP2022015181A - Paper tray with liner - Google Patents

Abstract

To provide a paper tray with liner allowing easy separation and segregation of a paper base material from a liner layer, forming the paper tray with liner, and having enough strength durable against external forces like dropping and vibration during handling or transportation.SOLUTION: A tray is formed by having a flatly continued flange surrounding a circumference of a tray body formed of a bottom surface and a side face. Plastic of a liner layer has a methylene group, and is heat-sealable. The liner layer and a paper base material can be peeled with the paper base material peeling. In FTIR spectrum from the liner layer side of the peeled liner layer, a ratio of a peak top A (%T) by paper base material-origin C-O stretching vibration to a peak top B (%T) by the liner layer-origin C-H stretch vibration is in a range of 0.50≤A/B≤2.5.SELECTED DRAWING: Figure 1

Description

The present invention relates to a paper tray with a liner. In particular, it is a paper tray with a liner that is composed of a liner layer made of plastic laminated on a paper base material, and is related to a paper tray with a liner that can be easily peeled off from the liner and the paper base material. be.

Paper trays are used as packaging materials for foods and the like in retail situations such as supermarkets and convenience stores. There are various forms, but since it is made of paper as a base material, it has excellent safety as well as price advantages, and is widely used as an environment-friendly packaging material even when it is disposed of. There is.

As a type of paper tray, for example, a paper tray with a liner made by assembling from flat blanks in which a liner made of plastic is laminated on a paper base material is also widely used. Further, the paper tray with a liner can be formed by using compressed air molding, press molding, or the like, and the shape thereof varies depending on the application.

This paper tray with a liner has water resistance and oil resistance due to the liner which is a plastic material, and therefore can store liquid or paste-like contents. Further, while the mechanical strength is excellent and the tray is easy to use, it is preferable that the liner and the paper can be separated and separated at the time of disposal after use from the viewpoint of environmental compatibility.

So far, paper trays that have made the paper substrate and liner layer separable generally have partial steps due to the split and separated paperboard structures that form the flanges, which in turn causes completeness. It was difficult to seal.

Attempts have also been made to reduce the interlayer strength between the paper layer and the liner layer in order to completely separate the paper substrate and the liner layer. There was a risk of delamination occurring. Further, the formation of the side surface and the bottom surface by such assembly is a temporary fixing by sealing the liner layer, and has a drawback that the strength of the entire tray is weak.

For example, Patent Document 1 proposes to assemble a tray using a blank of a tray in which a paper and a resin layer are laminated. However, for example, consideration for easy separation and separation of the paper layer and the resin layer at the time of disposal is considered. It wasn't done.

Japanese Unexamined Patent Publication No. 2000-25546

The present invention has been made in view of such a situation, and the paper base material and the liner layer constituting the paper tray with a liner can be easily separated and separated, and the paper base material and the liner layer can be easily separated and dropped, vibrated, etc. due to handling or transportation. The challenge is to provide a paper tray with a liner that has sufficient strength to withstand the external force of.

The invention according to claim 1 is a means for solving the above problems.
A paper-based tray, the tray is formed with a flat and continuous flange that surrounds the bottom and sides and the periphery of the tray body.
Of the components of the tray, at least the flange is composed of a liner layer made of plastic laminated on a paper base material.
The plastic of the liner layer has a methylene group and can be heat-sealed.
The liner layer and the paper base material can be peeled off with the paper peeling of the paper base material.
In the FTIR spectrum of the peeled liner layer from the liner layer side,
Peak top A (% T) due to CO expansion and contraction vibration derived from the paper substrate between 1000 cm ^-1 and 1100 cm ^-1
The ratio to the peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer between 2500 cm ^-1 and 3000 cm ^-1 is 0.50 ≤ A / B ≤ 2.5.
It is a paper tray with a liner, which is characterized by being in the range of.

Further, the invention according to claim 2 is based on the invention.
In the FTIR spectrum of the peeled liner layer from the liner layer side,
Peak top A (% T) due to CO expansion and contraction vibration derived from the paper substrate between 1000 cm ^-1 and 1100 cm ^-1
The ratio to the peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer between 2500 cm ^-1 and 3000 cm ^-1 is 0.80 ≤ A / B ≤ 2.0.
The paper tray with a liner according to claim 1, wherein the tray is in the range of 1.

Further, the invention according to claim 3 is based on the invention.
The paper tray with a liner according to claim 1 or 2, wherein the paper base material is made of paperboard having a basis weight of 40 g / m ² to 400 g / m ² .

According to the present invention, the paper base material and the liner layer constituting the paper tray with a liner can be easily separated and separated, and have sufficient strength to withstand external forces such as dropping and vibration due to handling and transportation. It is possible to provide a paper tray with a liner.

The plastic of the liner layer has a methylene group and can be heat-sealed, and is a thermoplastic, for example, a tray can be covered and the lid material can be heat-sealed and sealed. That is, when a lid material is used, the tray can be used as a packaging material for the purpose of protecting the contents.

Further, in the present invention, the liner layer and the paper base material can be easily peeled off with the paper peeling, and it is possible to achieve both separability and transport suitability depending on the level of the paper peeling. be.

Specifically, in the FTIR spectrum of the peeled liner layer from the liner layer side,
Peak top A (% T) due to CO expansion and contraction vibration derived from the paper substrate between 1000 cm ^-1 and 1100 cm ^-1
The ratio to the peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer between 2500 cm ^-1 and 3000 cm ^-1 is 0.50 ≤ A / B ≤ 2.5.
It is effective to achieve both separability and transportability of a paper tray with a liner within the range of.

In particular, according to the invention of claim 2, in the FTIR spectrum from the liner layer side of the above-mentioned peeled liner layer,
Peak top A (% T) due to CO expansion and contraction vibration derived from the paper substrate between 1000 cm ^-1 and 1100 cm ^-1
The ratio to the peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer between 2500 cm ^-1 and 3000 cm ^-1 is 0.80 ≤ A / B ≤ 2.0.
It is more effective to achieve the above range by achieving both separability and transportability of the paper tray with a liner.

In particular, according to the invention of claim 3, the paper base material constituting the paper tray with a liner is made of paperboard having a basis weight of 40 g / m ² to 400 g / m ² , thereby improving the strength and processability of the tray. It is effective for combining.

FIG. 1 is a schematic perspective view for explaining an embodiment of a paper tray with a liner according to the present invention. FIG. 2 is a plan-developed schematic view for explaining another embodiment of the paper tray with a liner according to the present invention. FIG. 3 is a partial cross-sectional schematic diagram for explaining a paper base material and a liner layer constituting the paper tray with a liner according to the present invention.

Hereinafter, the present invention will be described in more detail with reference to FIGS. 1 and 2. However, the present invention is not limited to the examples shown here. The present invention is specified by the claims.

FIG. 1 is a schematic perspective view for explaining an embodiment of a paper tray with a liner according to the present invention.

The present invention relates to a paper tray (10) with a liner using paper as a base material, and the tray has a bottom surface (2) and a side surface (3), and a flange (a flat continuous flange surrounding the peripheral edge of the tray body). It is formed with 1).

The paper tray (10) with a liner can store the contents in a recessed portion surrounded by the bottom surface (2) and the side surface (3), and the flange (3) is, for example, a lid material for covering the paper tray. It can be sealed and sealed as a packaging container. At this time, the lid material can be sealed to the continuous flange (1) flatly around the peripheral edge, and can be fused and sealed by, for example, heat sealing.

Further, the shape of the paper tray (10) with a liner is arbitrary as long as the flange (1) surrounds the tray body and its peripheral edge and is continuous flatly, as long as it does not hinder the storage of the contents. The molding method is also arbitrary, such as compressed air molding and press molding.

FIG. 2 is a plan-developed schematic view for explaining another embodiment of the paper tray with a liner according to the present invention.

In the example shown in FIG. 2, the flange (1) is an example of a rectangular shape, and the flange (1) is a continuous portion with diagonal lines. In this example, the paper tray (10) is assembled by forming a bottom surface (2) and a side surface (3) from a flat blank (11).

In the figure, the solid line of the blank (11) is the notch (12), and the broken line represents the fold line (13).

As described above, in the present invention, the flange (1) has an arbitrary shape such as an elliptical shape as shown in FIG. 1 or a rectangular shape as shown in FIG. 2, but has a continuous shape without joints or breaks. Is.

FIG. 3 is a partial cross-sectional schematic diagram for explaining a paper base material and a liner layer constituting the paper tray with a liner according to the present invention.

The paper tray (10) with a liner is composed of a laminated body (5), and among the components thereof, at least the flange (1) has a liner layer (7) made of plastic laminated on a paper base material (6). The laminated body (5) is configured.

In the present invention, the plastic of the liner layer (7) has a methylene group and can be heat-sealed, and the liner layer (7) and the paper base material (6) are accompanied by paper peeling (8) of the paper base material. It can be peeled off in the direction of the arrow (9).

Therefore, the peeled liner layer (7) is composed of the original plastic layer and the adhered paper peeling (8), and both spectra are detected in the FTIR spectrum from the liner layer (7) side. To.

Both spectra have a peak top A (% T) due to CO expansion and contraction vibration derived from a paper substrate between 1000 cm ^-1 and 1100 cm ^-1 wavenumber, and a liner layer between 2500 cm- ¹ and 3000 cm ^-1 wavenumber. It is the peak top B (% T) due to the derived CH expansion and contraction vibration.

In the process of diligently studying the present invention, we have a peak top A (% T) due to the CH expansion and contraction vibration derived from these paper substrates and a peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer. )
0.50 ≤ A / B ≤ 2.5
Within the range of the above, it is possible to easily separate and separate the paper base material (6) and the liner layer (7) constituting the paper tray (10) with a liner, which is an object of the present invention. Moreover, it has been found to be effective in providing a paper tray (10) with a liner having sufficient strength to withstand external forces such as dropping and vibration due to handling and transportation.

We further in the FTIR spectrum of the exfoliated liner layer from the liner layer side.
Peak top A (% T) due to CO expansion and contraction vibration derived from paper substrate between wave number 1000 cm ^-1 to 1100 cm ^-1
The ratio with the peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer between 2500 cm- ¹ to 3000 cm ^-1 wavenumber is
0.80 ≤ A / B ≤ 2.0
In the case of the above range, it is possible to easily separate and separate the paper base material (6) and the liner layer (7) constituting the paper tray (10) with a liner, which is an object of the present invention. It has also been found that it is even more effective in providing a paper tray (10) with a liner having sufficient strength to withstand external forces such as dropping and vibration due to handling and transportation.

That is, in the present invention, it is an object of the present invention that when the liner layer (7) and the paper base material (6) are peeled off, the state of the peeled surface is within a certain range of the paper peeling (8). The paper base material (6) and the liner layer (7) constituting the paper tray (10) with a liner can be easily separated and separated, and can withstand external forces such as drop vibration due to handling and transportation. It has been found that it is effective in realizing a paper tray (10) with a liner having sufficient strength.

The liner layers (7) can be overlapped and sealed so that the liner layers (7) face each other. For example, the overlapped portions can be bonded to each other by heating, pressurizing, and heat-sealing. For example, a lid material covers a paper tray (10) with a liner, and a flange (1) makes it possible to heat-seal and seal.

Further, in addition to the sealing property being given to the flange (1) portion by the liner layer (7), the liner layer (7) is provided on the entire inside of the bottom surface (2) and the side surface (3) of the tray. For example, oil resistance and water resistance can be imparted to the paper tray (10) with a liner, and the range of applicable contents can be expanded. For example, it is possible to store liquids and paste-like contents.

Of the thermoplastic resins, polyolefin resins are generally used as the material of the liner layer. Specifically, low-density polyethylene resin (LDPE), medium-density polyethylene resin (MDPE), and linear low-density polyethylene resin. (LLDPE), ethylene-vinyl acetate copolymer (EVA), ethylene-α-olefin copolymer, ethylene-methacrylic acid resin copolymer and other ethylene-based resins, polyethylene-polybutene blend resin, homopolypoly resin Polypropylene-based resins such as (PP), a propylene-ethylene random copolymer, a propylene-ethylene block copolymer, and a propylene-α-olefin copolymer can be used.

As the liner layer (7), in addition to the above-mentioned polyethylene resin and polypropylene resin, polyethylene terephthalate resin and polybutylene terephthalate resin can also be used, and any one or more of these can be used as a paper tray with a liner (7). It can be selected in consideration of the application of 10) and the required quality. In particular, when a polyethylene terephthalate resin or a polybutylene terephthalate resin is used, it is excellent in heat resistance to heating by a microwave oven, for example.

To form the liner layer (7), a molten resin can be formed by using an extruder or the like to form a layer on the front surface or both front and back surfaces of the mount. Alternatively, it is also possible to form the liner layer (7) on the surface of the paper base material (6) or on both the front and back surfaces by laminating a material that has been formed into a film in advance by laminating. The paper base material (6) and the liner layer (7) can be laminated via a molten adhesive polyethylene using, for example, an extruder.

Further, a polyethylene-based barrier multilayer film or a polypropylene-based barrier multilayer film having a gas barrier layer in the liner layer (7) is used to improve the gas barrier property, and the contents are deteriorated or deteriorated due to the influence of the environment. It is also possible to avoid this, and it is possible to improve the storage performance.

Further, the paper base material (6) constituting the laminated body (5) can be a paperboard having a basis weight of 40 g / m ² to 400 g / m ² . By using the paperboard in this range, the paper tray (10) with a liner can be made to have both strength and processability as a packaging container.

Further, when a paperboard having a basis weight in the range of 190 g / m ² to 350 g / m ² is used, it is more preferable in terms of strength and workability. Further, if necessary, a paper base material (6) coated with a gas barrier layer can also be used.

In this way, according to the present invention, the paper base material (6) and the liner layer (7) constituting the paper tray (10) with a liner can be easily separated and separated, and by handling and transportation. It is possible to provide a paper tray (10) with a liner having sufficient strength to withstand external forces such as dropping and vibration.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited to the examples shown here. The present invention is specified by the claims.

A paper tray (10) with a liner was prototyped and evaluated.
The materials used are as follows.
-Paper substrate: A food grade of 100% fresh pulp was used.
-Liner layer: Polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), or polybutylene succinate (PBS), which is a biodegradable plastic, can be used, all of which have a methylene group in the molecule. And selected one that can be heat-sealed.

When a polyethylene-based barrier multilayer film was used for the liner layer, the configuration was as follows.
Polyethylene (thickness 20 μm) / adhesive / ethylene-vinyl alcohol copolymer / adhesive / polyethylene (thickness 20 μm): Made by Mitsubishi Chemical Corporation.

When a polypropylene-based barrier multilayer film is used for the liner layer, the configuration is as follows.
Unstretched polypropylene (thickness 20 μm) / adhesive / ethylene-vinyl alcohol copolymer / adhesive / unstretched polypropylene (thickness 20 μm).

Peeling varnish: When adjusting the peeling level of the paper, PE64 peeling varnish C (manufactured by Toyo Ink) was applied to the paper substrate to adjust the degree of adhesion of the liner layer.

Measurement method: The measurement by FTIR is as follows.
Spectral analysis from the liner surface of the stripped sample was performed by the ATR method using an FTIR measuring instrument (Spoillight200-FortierMIR) manufactured by PerkinElmer.

Peak top A (% T) due to CHO expansion and contraction vibration derived from the paper substrate between 1000 cm ^-1 and 1100 cm ^-1 , and CH expansion and contraction vibration derived from the liner layer between 2500 cm ^-1 and 3000 cm ^-1 . The ratio A / B with the peak top B (% T) was calculated.

The evaluation items are as follows.
-Separability: The peelability between the liner and the paper substrate was evaluated.
We asked 30 panelists to peel off the liner and the paper substrate and evaluated them.

The evaluation criteria are as follows.
⊚: When it is judged that 27 or more people are easy to separate.
〇: When it is judged that 24 or more people are easy to separate.

-Liquid leakage: A penetrant was placed in a paper tray and stored over time (40 ° C, 75%).
The evaluation criteria are as follows.
〇: Those that did not leak in one month.
×: Liquid leakage occurred within one month.

-Transportability: Based on JIS Z 0200, 200 g of contents were put in and a drop and vibration test was carried out.
The evaluation criteria are as follows.
〇: There is no separation between the liner and the paper substrate.
X: Separation of the liner and the paper substrate occurred.

<Example 1>
The shape of the flange of Example 1, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polybutylene succinate (thickness 25 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.5.
This value is within the range specified in claim 1 of the present invention.

<Example 2>
The shape of the flange of Example 2, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 15 μm) / peeling varnish paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.5.
This value is within the range specified in claim 1 of the present invention.

<Example 3>
The shape of the flange, the layer structure of the liner layer and the paper base material, and the state of paper peeling in Example 3 are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 15 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.6.
This value is within the range specified in claim 1 of the present invention.

<Example 4>
The shape of the flange, the layer structure of the liner layer and the paper base material, and the state of paper peeling in Example 4 are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 18 μm) / paper (260 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.7.
This value is within the range specified in claim 1 of the present invention.

<Example 5>
The shape of the flange, the layer structure of the liner layer and the paper base material, and the state of paper peeling in Example 5 are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 15 μm) / barrier coated paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.8.
This value is within the range specified in claim 1 of the present invention, and is also within the range specified in claim 2.

<Example 6>
The shape of the flange, the layer structure of the liner layer and the paper base material, and the state of paper peeling in Example 6 are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.8.
This value is within the range specified in claim 1 of the present invention and also within the range specified in claim 2.

<Example 7>
The shape of the flange of Example 7, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Unstretched polypropylene film (thickness 30 μm) / adhesive polypropylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.8.
This value is within the range specified in claim 1 of the present invention and also within the range specified in claim 2.

<Example 8>
The shape of the flange, the layer structure of the liner layer and the paper base material, and the state of paper peeling in Example 8 are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 15 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 0.8.
This value is within the range specified in claim 1 of the present invention and also within the range specified in claim 2.

<Example 9>
The shape of the flange of Example 9, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 1.0.
This value is within the range specified in claim 1 of the present invention and also within the range specified in claim 2.

<Example 10>
The shape of the flange of Example 10, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polybutylene succinate (thickness 25 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value was 1.1.
This value is within the range specified in claim 1 of the present invention and also within the range specified in claim 2.

<Example 11>
The shape of the flange of Example 11, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 1.5.
This value is within the range specified in claim 1 of the present invention and also within the range specified in claim 2.

<Example 12>
The shape of the flange of Example 12, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 15 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 2.0.
This value is within the range specified in claim 1 of the present invention and also within the range specified in claim 2.

<Example 13>
The shape of the flange of Example 13, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 15 μm) / barrier coated paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 2.2.
This value is within the range specified in claim 1 of the present invention.

<Example 14>
The shape of the flange of Example 14, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 2.3.
This value is within the range specified in claim 1 of the present invention.

<Example 15>
The shape of the flange of Example 15, the layer structure of the liner layer and the paper base material, and the state of paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene (thickness 30 μm) / adhesive polyethylene (thickness 18 μm) / paper (260 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 2.5.
This value is within the range specified in claim 1 of the present invention.

<Comparative Example 1>
The shape of the flange of Comparative Example 1, the layer structure of the liner layer and the paper base material, and the state of the paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 3.0.
This value is out of the range specified in claim 1 of the present invention and is different from the embodiment.

<Comparative Example 2>
The shape of the flange of Comparative Example 2, the layer structure of the liner layer and the paper base material, and the state of the paper peeling are as follows.
Flange: Circular (continuous shape without seams or breaks)
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: Almost no paper peeling. The A / B value according to FTIR was 0.4. This value is out of the range specified in claim 1 of the present invention and is different from the embodiment.

<Comparative Example 3>
The shape of the flange of Comparative Example 3, the layer structure of the liner layer and the paper base material, and the state of the paper peeling are as follows.
Flange: Separation. That is, the flanges are not continuous and deviate from the range specified in the present invention.
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 1.3.

<Comparative Example 4>
The shape of the flange of Comparative Example 4, the layer structure of the liner layer and the paper base material, and the state of the paper peeling are as follows.
Flange: Has wrinkles. In the present invention, the flange is flat, and this portion deviates from it.
Layer structure: Polyethylene-based barrier multilayer film (thickness 50 μm) / adhesive polyethylene (thickness 18 μm) / paper (310 g / m ² )
Paper peeling condition: There is paper peeling. The A / B value according to FTIR was 1.8.

The evaluation results are shown in Table 1.

As can be seen from the results shown in Table 1, Examples 1 to 15 of the paper tray with a liner according to the present invention are evaluated as 〇 or ◎ in all three items of separability, liquid leakage, and transportability. ..

On the other hand, in Comparative Examples 1 to 4, which may deviate from the range specified in the present invention, any one of the three items of separability, liquid leakage, and transport suitability is evaluated as ×. The superiority of the paper tray with liner according to the present invention is clear.

Hereinafter, individual examples and comparative examples will be considered.
In Example 1, the value of A / B is 0.5, which is the lower limit within the range of the value specified in the present invention. All three items, separability, liquid leakage, and transport suitability, are evaluated as 〇.

Whether or not the paper was peeled off was evaluated as 〇, and a paper-rich state was observed. In addition, the liner layer is polybutylene succinate, which is a biodegradable plastic, so that the liner layer is also decomposed after being separated and discarded, so it is made of paper with a liner that is more environmentally friendly. It is a tray.

In Example 2, the value of A / B is 0.5, which is the lower limit within the range of the value specified in the present invention. All three items, separability, liquid leakage, and transport suitability, are evaluated as 〇.

In Example 3, the value of A / B is 0.6, which is within the range of the value specified in the present invention. All three items, separability, liquid leakage, and transport suitability, are evaluated as 〇.

In Example 4, the value of A / B is 0.7, which is within the range of the value specified in the present invention. All three items, separability, liquid leakage, and transport suitability, are evaluated as 〇.

In Example 5, the value of A / B is 0.8, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇. Barrier-coated paper is used as the paper base material, which improves the gas barrier property and is effective in improving the storage stability of the contents.

In Example 6, the value of A / B is 0.8, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇. Further, a polyethylene-based barrier multilayer film (thickness 50 μm) is used for the liner layer, and by having a gas barrier property, it is effective in improving the storage stability of the contents.

In Example 7, the value of A / B is 0.8, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇. Further, polypropylene is used for the liner layer, which is superior in heat resistance to polyethylene.

In Example 8, the value of A / B is 0.8, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇.

In the ninth embodiment, the value of A / B is 1.0, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇. Further, a polyethylene-based barrier multilayer film (thickness 50 μm) is used for the liner layer, and by having a gas barrier property, it is effective in improving the storage stability of the contents.

In Example 10, the value of A / B is 1.1, which is the lower limit of the value specified in the present invention. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇. In addition, the liner layer is polybutylene succinate, which is a biodegradable plastic, so that the liner layer is also decomposed after being separated and discarded, so it is made of paper with a liner that is more environmentally friendly. It is a tray.

In the eleventh embodiment, the value of A / B is 1.5, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇. Further, a polyethylene-based barrier multilayer film (thickness 50 μm) is used for the liner layer, and by having a gas barrier property, it is effective in improving the storage stability of the contents.

In Example 12, the value of A / B is 2.0, which is the upper limit within the range of the value specified in claim 1 of the present invention, particularly within the range of the value specified in claim 2. In particular, the separability is evaluated as ◎, and the liquid leakage and transport suitability are evaluated as 〇.

In Example 13, the value of A / B is 2.2, which is within the range of the value specified in claim 1 of the present invention. All three items, separability, liquid leakage, and transport suitability, are evaluated as 〇.
Barrier-coated paper is used as the paper base material, which improves the gas barrier property and is effective in improving the storage stability of the contents.

In Example 14, the value of A / B is 2.3, which is within the range of the value specified in claim 1 of the present invention. All three items, separability, liquid leakage, and transport suitability, are evaluated as 〇. Further, a polyethylene-based barrier multilayer film (thickness 50 μm) is used for the liner layer, and by having a gas barrier property, it is effective in improving the storage stability of the contents.

In Example 15, the value of A / B is 2.5, which is the upper limit of the value specified in the present invention. All three items, separability, liquid leakage, and transport suitability, are evaluated as 〇.
The possibility of paper peeling was evaluated as 〇, the paper peeling was relatively small, and the resin-rich state of the liner layer was observed.

In Comparative Example 1, the value of A / B is 3.0, which deviates upward from the value specified in the present invention. As a result, separability and liquid leakage are evaluated as 〇, and transportability is evaluated as ×. The result was that the liner layer and the paper substrate were easily peeled off by an external force.
Whether or not the paper was peeled off was evaluated as 〇, and the paper peeling was relatively small, and the state of almost only the resin of the liner layer was observed.

In Comparative Example 2, the A / B value is 0.4, which deviates downward from the value specified in the present invention. As a result, the separability is evaluated as x, liquid leakage, and transportability are evaluated as 0. Paper peeling was evaluated as x, and almost only paper was observed.

In Comparative Example 3, the value of A / B is 1.3, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. Separability is evaluated as 〇. However, liquid leakage and transport suitability are evaluated as x. This indicates that the flange deviates from the state of being flat and continuous as defined in the present invention, and this portion impairs the sealing property and is vulnerable to external force due to transportation or the like. There is.

Further, a polyethylene-based barrier multilayer film (thickness 50 μm) is used for the liner layer, and by having a gas barrier property, it is effective in improving the storage stability of the contents, but for the above reason, it can be used as a container. Practicality remains questionable.

In Comparative Example 4, the value of A / B is 1.8, which is within the range of the value specified in claim 1 of the present invention, particularly the value specified in claim 2. Separability is evaluated as 〇. However, liquid leakage and transport suitability are evaluated as x. This indicates that the flange deviates from the state of being flat and continuous as defined in the present invention, and this portion impairs the sealing property and is vulnerable to external force due to transportation or the like. There is.

Further, a polyethylene-based barrier multilayer film (thickness 50 μm) is used for the liner layer, and by having a gas barrier property, it is effective in improving the storage stability of the contents, but for the above reason, it can be used as a container. Practicality remains questionable.

In this way, according to the present invention, the paper base material and the liner layer constituting the paper tray with a liner can be easily separated and separated, and can withstand external forces such as dropping and vibration due to handling and transportation. It was possible to verify that it is possible to provide a paper tray with a liner that has sufficient strength.

1 ... Flange 2 ... Bottom surface 3 ... Side surface 5 ... Laminated body 6 ... Paper base material 7 ... Liner 8 ... Paper peeling 9 ... Arrow 10 ... With liner Paper tray 11 ... Blank 12 ... Notch 13 ... Folded line

Claims (3)

It is a paper tray with a liner made of paper as a base material, and the tray is formed by having a flat continuous flange surrounding the bottom surface and the side surface and the peripheral edge of the tray body.
Of the components of the tray, at least the flange is composed of a liner layer made of plastic laminated on a paper base material.
The plastic of the liner layer has a methylene group and can be heat-sealed.
The liner layer and the paper base material can be peeled off with the paper peeling of the paper base material.
In the FTIR spectrum of the peeled liner layer from the liner layer side,
Peak top A (% T) due to CO expansion and contraction vibration derived from the paper substrate between 1000 cm ^-1 and 1100 cm ^-1
The ratio to the peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer between 2500 cm ^-1 and 3000 cm ^-1 is 0.50 ≤ A / B ≤ 2.5.
A paper tray with a liner, characterized by being in the range of. In the FTIR spectrum of the peeled liner layer from the liner layer side,
Peak top A (% T) due to CO expansion and contraction vibration derived from the paper substrate between 1000 cm ^-1 and 1100 cm ^-1
The ratio to the peak top B (% T) due to the CH expansion and contraction vibration derived from the liner layer between 2500 cm ^-1 and 3000 cm ^-1 is 0.80 ≤ A / B ≤ 2.0.
The paper tray with a liner according to claim 1, characterized in that it is in the range of. The paper tray with a liner according to claim 1 or 2, wherein the paper base material is made of paperboard having a basis weight of 40 g / m ² to 400 g / m ² .

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