JP6015036B2 - Laminated base paper and insulated container using the same - Google Patents

Description

  The present invention manufactures a container for eating and drinking in a hot state after pouring hot water such as coffee, tea, cocoa, urine, amazake, instant noodles, instant buckwheat, instant vermicelli, instant soup, and the like. Regarding laminated base paper.

  Pour hot water, such as coffee, tea, cocoa, urine, amazake, instant noodles, instant soba noodles, instant vermicelli, instant soup, etc. to melt or reconstitute soups, seasonings, powders, or other solid contents For example, a container for cooking and eating by heating needs to be a heat-resistant container. Therefore, the heat cooking container needs to have a heat resistance of 100 ° C. or higher. In addition, when it is expected to eat and drink with the hand in hand, it is necessary to insulate the high temperature from being transmitted to the container surface and to prevent heat from being transmitted to the hand holding the container. It was.

  The main of many disposable containers are paper cups used in vending machines such as coffee, tea and cocoa. Since it is paper, it has some heat insulation, and the paper adhesive is heat and water resistant, so the contents will not ooze or spill, but the surface temperature will rise to around 80 ° C. . It is possible to hold it for a moment, but it is a container that can not be held for a long time, leave it to cool, eat and drink after it has reached the appropriate temperature, or put it on the table without holding it in your hand Then, I sipped with chopsticks and spoons, took only the amount to put in my mouth, cooled and ate while eating and drinking.

  In addition, there are expanded polystyrene cups and the like that have been used in fast food stores. This container uses styrene, has no joints, has high heat resistance, and has improved heat insulation compared to a paper cup. However, when the contents close to 100 ° C are poured, the surface exceeds 60 ° C. The problem of becoming too hot to eat and drink for a long time has not been solved.

In order to solve the above-described problem, in Patent Document 1, a two-layer structure heat insulating film composed of a foamed inner layer of a thermoplastic resin having a low melting point and a non-foamed layer of a thermoplastic resin having a melting point higher than that of the thermoplastic resin is applied. A container is disclosed.
In this document, the two-layer structure heat insulating film is used on the outside of the paper or on both the inside and outside of the paper. And it describes that only the low melting point thermoplastic resin layer is foamed by heating and evaporation of moisture contained in the paper.

  In Patent Document 2, a relatively thick foam heat insulating layer made of a thermoplastic synthetic resin film on a printed portion of an organic solvent-containing ink on an outer wall surface of a container body member, and a relatively thin foam made of a thermoplastic synthetic resin film on a non-printed portion. An insulating paper container with an insulating layer is described.

In addition, Patent Document 3 includes a thermoplastic resin foam layer, a printing layer, a paper-based base material layer, and a thermoplastic resin layer from the outside, and is provided between the thermoplastic resin foam layer and the paper-based base material layer. Describes a foamed paper cup having a transparent varnish layer formed thereon.
In these containers, there is no complete heat insulating function, and the container gradually becomes hot, and there is a problem that it is too hot to eat and drink while holding it.

A material in which a foamed PS sheet is wound around the outside of paper as a material having a large heat insulation effect with respect to a container having these resin layers has a sufficient heat insulation effect as a container for containing the high-temperature contents. However, since the heat of the contents is not transmitted at all, there is a problem that it is difficult to understand whether it is really hot or how cold it is to drink. For this reason, even though it is still very hot, it is not noticeable, and accidents such as burning the tongue, hurting the throat, or spilling and burning the hands and feet are likely to occur.
In view of the above problems, the present inventor has invented a container that can feel whether the contents have reached an appropriate temperature, and that can be held for a long time without becoming too hot.

JP-A-5-42929 Japanese Patent Laid-Open No. 7-232774 JP-A-9-142435

The first problem of the present invention is to make a heat-resistant and heat-insulating container that can only rise to a temperature at which the surface temperature can be maintained for a long time even when hot water of 100 ° C. is present inside.
In addition, the second problem is not to know whether the contents are hot or cold due to over-insulation, but it is possible to feel the temperature of the contents by appropriately transferring the heat of the contents to the container surface. It is to make a container.

In order to achieve the above object, a laminated base paper according to claim 1 of the present invention is a laminated base paper in which both sides of paper used for a heat insulating container are coated with a synthetic resin, and the melting point is the foaming temperature of the outer resin layer as the inner resin layer. Using the above polyethylene resin, the outer resin layer contains a low melting point resin of 100 ° C. or lower ,
An outer resin layer containing a low melting point resin having a melting point of 100 ° C. or lower has a linear low density polyethylene (LLDPE) having a melting point of 100 ° C. or lower, and a low density polyethylene resin (LDPE) having a melting point of 100 ° C. or more on the outside. )
The linear low density polyethylene (LLDPE) having a melting point of 100 ° C. or lower is a metallocene catalyst-based linear low density polyethylene,
The inner resin layer has a density of 0.936, a laminate sheet having a melting point was characterized by Ru density polyethylene Tona in the 126 ° C..

The laminated base paper according to claim 2 is a laminated base paper in which both sides of paper used for a heat insulating container are covered with a synthetic resin, and the inner resin layer is made of a polyethylene resin having a melting point equal to or higher than the foaming temperature of the outer resin layer. The resin layer contains a low melting point resin of 100 ° C. or lower,
An outer resin layer containing a low melting point resin having a melting point of 100 ° C. or lower has a linear low density polyethylene (LLDPE) having a melting point of 100 ° C. or lower, and a low density polyethylene resin (LDPE) having a melting point of 100 ° C. or more on the outside. )
The outer resin layer is composed of linear low density polyethylene, ethylene vinyl acetate copolymer resin (EVA), ethylene / methacrylic acid copolymer resin (EMAA), ethylene acrylic acid copolymer resin (EAA), or ionomer resin. A mixed resin containing a low-melting point resin having a melting point of 100 ° C. or lower and a low-density polyethylene resin having a melting point of 100 ° C. or higher, consisting of at least one of polypropylene resin and polybutene resin,
The inner resin layer is a laminated base paper characterized by being made of medium density polyethylene having a density of 0.936 and a melting point of 126 ° C.

Then laminated sheet according to claim 3, the outer layer of the outer resin composed of the mixed resin, further, according to claim 2, characterized in that laminated with melting point 100 ° C. or more low-density polyethylene resin Laminated base paper.

Insulated container then according to claim 4, using a laminate sheet according to any one of claims 1 to 3, a heat insulating container, characterized in that imparted sectional heat.

The container using the laminated base paper of the present invention can suppress the rise in surface temperature due to the large heat absorption of resin melting, so the temperature does not become extremely high. Therefore, even if hot water or soup of about 100 ° C. is put, Since the temperature is suppressed to 60 ° C. or lower and the rigidity does not decrease, the container can be held for a long time.
On the contrary, even if such high-temperature contents are poured into the container, the temperature of the surface of the container rises to a temperature around 50 ° C., but it is felt that the inside of the container is hot at a temperature that is not too hot. The contents inside the container are not easily swallowed and the throat is burned.

  In addition, since the laminated base paper can be produced with a normal laminating machine, it does not require any special installation or modification of equipment, so that it can be started up in a short period of time and is excellent in mass productivity.

It is a partial expanded sectional view of one reference example of the laminated base paper of this invention. It is the perspective view (2-1) and sectional drawing (2-2) showing an example of the container shape which uses the laminated base paper of this invention. It is the graph which showed the temperature change in the container outer surface when hot water is poured into the container of various structures. It is the graph which showed the temperature change in the outer surface of a container when hot water was poured into the container created with the laminated base paper of this invention, and the container created with the conventional expanded polystyrene, and the temperature change of hot water. It is a cross-sectional structure diagram showing an example of a laminate base paper of a conventional configuration. It is a partial expanded sectional view showing an example of the lamination base paper of the present invention. It is a partial expanded sectional view showing other examples of the lamination base paper of the present invention. It is the partial expanded sectional view showing another example of the lamination base paper of this invention.

  Hereinafter, a laminated base paper of the present invention and a container using the laminated base paper will be described with reference to the drawings.

FIG. 1 shows a configuration of one reference example of the laminate base paper of the present invention. What is actually used is a cylindrical shape such as a cup shown in FIG. As shown in section 2-2 in the section, the sheet is pulled out into a shape, and the connecting portion 4 of the trunk and the bottom portion is a normal cup shape made by fusing. Of course, the cup shape may be a square tube shape or a bag shape, but the cup shape is preferable because it has a large capacity, is easy to hold, is easy to place, and has strength and rigidity.
The laminated base paper used for this container is mainly made of paper 1 and both sides are covered with a synthetic resin, but the synthetic resin is changed between the inner resin layer 3 and the outer resin layer 2. That is, a resin having a low melting point is used for the outer resin layer 2, and a normal polyethylene resin having a melting point of 105 ° C. to 130 ° C. that is not a low melting point is used for the inner resin layer 3.
At this time, the low melting point resin layer 7 used as the outer resin layer is made of low density polyethylene having a low melting point of 100 ° C. or lower.
Examples of the low density polyethylene resin having a melting point of 100 ° C. or lower include Sumitomo Chemical's Excellen FX CX2001 (melting point 94 ° C.), CX3007 (melting point 83 ° C.), Ube Industries' UBE super polyethylene 0540F (melting point 87 ° C.), 1540F (melting point 99 ° C.) ), Evolution Metallocene SP0510 (melting point: 98 ° C.) manufactured by Prime Polymer Co., Ltd.

  The metallocene catalyst-based linear low density polyethylene used in the present invention is made by copolymerization of ethylene and α-olefin, has a very narrow molecular weight distribution and composition distribution, and is excellent in heat sealability and strength at low temperatures. In other words, a resin called metallocene plastomer is used. An ultra-low density resin can be synthesized. Due to the uniform comonomer composition distribution, tie molecules are formed in the solid state, and there are high tensile strength and high impact strength. Moreover, there is little stickiness and heat sealability is good. Utilizing this property, the present inventor uses a resin having a melting point of 100 ° C. or less in the metallocene catalyst-based linear low-density polyethylene resin for the outer layer of the container, and foams it, and the heat insulation effect by the foaming is obtained. The invented laminated base paper and the container using it were invented.

For the outer resin layer 2 of the laminated base paper of the present invention, among the above metallocene catalyst-based linear low density polyethylene resins, particularly those having a resin density of less than 0.9 and a melting point of 60 ° C. or less are used. It is effective.
Such resin is commercially available from Nippon Polyethylene Co., Ltd. as KC650T, a commercial name kernel having a melting point of 55 ° C. and a density of 0.888. As the modifying resin, Kernel KJ640T having a melting point of 58 ° C. and a density of 0.880, Kernel KS240T having a melting point of 60 ° C. and a density of 0.880 are commercially available, and these resins can be used.
This low-melting resin has a thickness of 40 μm to 120 μm, preferably 60 μm to 100 μm, in order to reliably exhibit the heat insulating effect due to foaming. When the thickness is less than 40 μm, there is a problem that even if foaming is performed, the film is too thin and the heat insulating effect is difficult to be obtained, or foaming is performed too much and the fusing power of paper or the like is reduced. In addition, when the thickness is 120 μm or more, it becomes difficult to mold the container into a cup shape or the like, and when it is made into a container such as a cup, there is a problem that leakage is likely to occur due to weakness and weak fusion. To do.

  The inner resin layer 3 may be a general-purpose polyethylene resin having a melting point of 105 ° C. or higher, and may be a Ziegler-Natta catalyst polyethylene, a Philips catalyst polyethylene, a gas phase metallocene polyethylene, or the like.

The gas to be foamed is moisture contained in the paper, and the paper is laminated after adjusting the moisture so that the paper contains a humidity of 4 to 12 percent, preferably 7 to 8 percent.
As the paper itself, paper having a thickness of 100 to 400 g / m ^2, preferably 200 to 400 g / m ² is used. This is because it is difficult to make the paper that is too thin contain sufficient foaming moisture, and if it is too thick, it will be too stiff and difficult to be molded into a container.
Since the inner layer of these papers has a resin layer having a high melting point, the inner resin layer 3 is not in a molten state even when a temperature of about 100 ° C. is applied. Even if it is applied, the viscosity is still higher than that of the outer low melting point resin layer 7, and water vapor does not easily pass therethrough. Therefore, the moisture contained in the paper is dammed by the inner layer resin on the inside even if it tries to penetrate. Therefore, the moisture contained in the paper is transferred to the low melting point resin layer 7 where heat begins to dissolve, penetrates the outer low melting point resin layer 2 where the viscosity is lower than that of the inner resin layer and water vapor easily flows, and boils there. The low melting point resin layer that becomes a gas and melts at that temperature foams 10 to 15 times.

FIG. 3 shows changes in the container surface temperature when hot water is filled for each base paper used in the container in the shape of the cup container of FIG. 2 in the present invention.
The high temperature danger area A in the graph of FIG. 3 is an area where the surface temperature is 70 ° C. or higher in an area where the temperature is very high, the burn is caused even in a short contact, and the container cannot be held with bare hands.
The B high temperature caution area is a temperature range where the container cannot be held with bare hands for a long time at a surface temperature of 60 ° C. to 70 ° C.
The C high temperature safety range is a temperature at which the container can be held for a long time, but the temperature inside the container can be felt from the outside, and is a surface temperature from 40 ° C to 60 ° C.
The low temperature region D is a temperature at which the temperature is not transmitted and the internal temperature is hardly felt from the outer surface, and the surface temperature is 40 ° C. or lower.

In the graph of FIG. 3, the paper cup of S1 uses a laminated base paper in which the front and back sides of the paper are coated with ordinary polyethylene, or a laminated base paper in which only the inside is coated with polyethylene. The heat insulation is low, and the container surface is very hot. turn into.
The foamed polyethylene cup (foamed PE cup) of S2 is made of a sheet in which polyethylene is laminated on the front and back of paper, and a polyethylene layer provided on the outside is foamed to give heat insulation. Since the polyethylene layer has a foaming ratio of about 8 times, heat conduction is large, and the container surface exceeds 60 ° C. and cannot be held for a long time.
Since the expanded polystyrene sheet-wound cup of S4 has an expansion ratio of 20 to 50 times, it has sufficient heat insulation. However, its thermal insulation is too high, heat is not transmitted to the container surface, and it is difficult to detect the temperature state of the contents. On the other hand, the contents are hot. Come. In addition, the rigidity is greatly reduced at high temperatures, and problems such as deformation due to softening of the internal high temperature portion are likely to occur.
An appropriate temperature cup, which is a heat insulating container using the laminated base paper of the present invention of S3, is at 60 ° C. or lower even if it rises, and is in a C high temperature safety region where the temperature inside the container can be sufficiently felt from the outside.

FIG. 4 shows a detailed relationship between temperature and time in the heat insulating container using the laminated base paper of the present invention as the S3 appropriate temperature cup, as compared with the S2 foamed PE cup.
The suitable temperature cup, which is a heat insulating container using the laminated base paper of the present invention of S3, has a temperature rise after pouring hot water, and when the outer layer surface is 60 ° C. or less, the crystal of the low melting point resin layer 2 is melted inside. As a result, the heat is absorbed by the heat of fusion at which the crystals disappear, and the rise is suppressed. Moreover, on the inner side surface of the outer resin layer 2 made of a low melting point resin that has started to melt, heat conduction is suppressed by foaming, heat is hardly transmitted to the surface, and the temperature difference between the inner side and the outer side becomes larger. After a while, the crystal inside the outer resin layer 2 is in a molten state, and then the temperature rises again. However, at that time, since time has passed, the heat has escaped and the hot water temperature has decreased. Then, the temperature rise after that is small, does not rise above 60 ° C., and then falls. Therefore, although it feels hot, it is not a temperature that burns, but it is a container that keeps it at the proper temperature.

In contrast to the above film configuration, in the configuration of FIG. 6, linear low density polyethylene (L-LDPE) is used as the low density polyethylene resin of the low melting point resin layer 7 provided just outside the paper layer. Further, in the configuration of FIG. 6, a surface resin layer 9 made of general-purpose low-density polyethylene is provided outside the linear low-density polyethylene.
The low melting point resin used here has a low melting point of 100 ° C. or less, and is also a linear low density polyethylene. Among them, a metallocene catalyst type linear low density polyethylene (mL-LDPE) is used. Is more suitable.
As a countermeasure against the occurrence of tackiness due to heat in the layer on the surface of the hand, the general-purpose linear low-density polyethylene resin layer provided on the outside is made into a metallocene catalyst-based linear low-density polyethylene, and further to the outside A surface resin layer 9 made of general-purpose high melting point polyethylene was provided.
The general-purpose low-density polyethylene can be high-pressure low-density polyethylene using the oxygen catalyst of Imperial Chemical Industries (ICI), Philip method, standard method, or other manufacturing methods, but the melting point Is polyethylene having a melting point of about 105 ° C. or higher. If possible, polyethylene at 103 ° C to 107 ° C is preferred.

In FIG. 7, as the outer resin, linear low density polyethylene (LLDPE) having a melting point of 100 ° C. or lower, ethylene vinyl acetate copolymer resin (EVA), ethylene / methacrylic acid copolymer resin (EMAA), ethylene acrylic A mixed resin layer 8 containing at least two of acid copolymer resin (EAA), ionomer resin, polypropylene resin, and polybutene resin is used.
Among these, ethylene vinyl acetate copolymer resin (EVA) has a melting point that varies depending on the content of vinyl acetate, and at a content of 40% or more, it does not crystallize at room temperature. If the content of vinyl acetate is 7% or more, the melting point is 100 ° C. or less.
The melting point of ethylene / methacrylic acid copolymer resin (EMAA) and ionomer resin also varies depending on the content of methacrylic acid. When the methacrylic acid is 9% or more, the melting point becomes 100 ° C. or less, so such a resin is used. Specifically, in the case of ethylene / methacrylic acid copolymer resin, Nukurel N410 (MAA 9%, melting point 98 ° C.), N035C (MAA 10%, melting point 68 ° C.) manufactured by Mitsui DuPont Polychemical Co., Ltd. Among ionomer resins, there is HiMilan 1554 (zinc type, melting point 97 ° C.) manufactured by Mitsui DuPont Polychemical Co., Ltd.
Furthermore, the melting point of the polypropylene resin is homo and 165 ° C., but the melting point of the polypropylene resin copolymerized with polyethylene is 135 ° C. to 150 ° C. for the random type, 160 ° C. to 165 ° C. for the block type, and the melting point of polybutene is 129 ° C. These are not used as low melting point resins but as aggregates made from general-purpose molten resins.

  Using a resin as described above, including a resin having a melting point of 100 ° C. or lower, the mixed resin containing at least two is distributed in a micellar state on the micro and after they are molded into a container When heated, the low melting point resin inside the layer, that is, the portion in contact with the paper, is converted into melting energy to absorb heat and melt. Then, the water contained in the paper starts to volatilize, the volume increases, and foams out of the paper. However, since the aggregate component by general-purpose resin, such as the polypropylene resin and polybutene resin which are not the low melting point contained, does not melt, the whole does not melt.

  In FIG. 8, a surface resin layer 9 made of a general-purpose polyethylene resin is provided on the outer side of the outer mixed resin layer 8 provided with the mixed resin. As in the configuration of FIG. 6, general-purpose low-density polyethylene has a melting point of 100 ° C. or higher, and is laminated with polyethylene having a melting point of around 105 ° C., preferably 103 ° C. to 107 ° C. In addition to reducing the property and softening, it has the role of ensuring rigidity, having no hindrance to grasping by hand, and making it possible to lift more stably.

The lamination base paper of the present invention processed in this way is produced by ordinary extruder lamination or dry lamination. The paper at the time of manufacture needs to be moisture-conditioned, and even after the lamination base paper is manufactured, it is necessary to maintain the moisture absorption state until foaming.
That is, since foaming is an element that foams paper and is an element that imparts heat insulation properties, it is necessary to complete foaming by processing into a container such as a cup while the moisture content absorbed is not changed. Because of that.

The present invention is a lamination base paper as described above, and the low-melting point resin layer 7 is foamed and processed into a heat-insulating container after molding.
This lamination base paper is manufactured by ordinary extruder lamination or dry lamination. The paper at the time of manufacture needs to be moisture-conditioned, and even after the lamination base paper is manufactured, it is necessary to maintain the moisture absorption state until foaming.
That is, since foaming is an element that foams paper and is an element that imparts heat insulation properties, it is necessary to complete foaming by processing into a container such as a cup while the moisture content absorbed is not changed. Because of that.

Such a lamination base paper of the present invention is cut into a predetermined shape with a punching die, bent with a cup making machine, and then shaped into a cup shape by fusing the bottom surface and the back of the trunk. Then, it was put into a furnace at 110 ° C. to 130 ° C. for several minutes to foam the low melting point resin portion layer.
It is necessary to change the foaming temperature and time depending on the furnace structure and the specifications of the laminated base paper. If the temperature is too low, foaming does not occur vigorously and manufacturing takes time. However, when the temperature is too high, the shape changes due to remelting of the seal portion of the container that is not desired to be melted. Therefore, the condition of the furnace is set by confirming the foaming state.

< Reference Example 1>
1 , the inner resin layer 3 has a density: 0.936, a melting point: 126 ° C. medium density polyethylene, a thickness of 30 μm,
Paper 1 has a thickness (unit weight) of 300 g / m ² , a moisture content of 8%,
The low-melting point resin layer 7 made of a paper outer resin is a metallocene catalyst-based linear low-density polyethylene having a density of 0.888, a melting point of 55 ° C. and a thickness of 70 μm
Was molded into a 300 ml capacity cup in FIG. 2 and foamed at 120 ° C. for 10 minutes to prepare a heat insulating container.

<Example 1 >
6, the inner resin layer 3 has a density of 0.936, a melting point of 126 ° C. medium density polyethylene, a thickness of 30 μm,
Paper 1 has a thickness (unit weight) of 300 g / m ² , a moisture content of 8%,
The low-melting point resin layer 7 is a metallocene catalyst-based linear low-density polyethylene with a density of 0.888, a melting point of 55 ° C., and a thickness of 70 μm.
The surface resin layer 9 provided outside the low melting point resin is a general-purpose low density polyethylene, density: 0.918, melting point: 106 ° C., thickness 16 μm.
In the same manner as in Reference Example 1, a cup with a capacity of 300 ml in FIG. 2 was molded and foamed at 120 ° C. for 10 minutes to prepare an insulated container.

<Example 2 >
In the configuration of FIG. 7, the inner resin layer 3 has a density of 0.936, a melting point of 126 ° C. medium density polyethylene, a thickness of 30 μm,
Paper 1 has a thickness (unit weight) of 300 g / m 2, a moisture content of 8%,
As a low-melting-point resin outside the paper, a metallocene polyolefin plastomer having a density of 0.870 and a melting point of 53 ° C. and a low-density polyethylene (LDPE) having a density of 0.921 and a melting point of 110 ° C. as a general-purpose resin are used. 70 μm of mixed resin layer (8) mixed at a ratio of 1: 1
As in Reference Example 1, it was molded into a 300 ml capacity cup in FIG. 2 and then foamed at 120 ° C. for 10 minutes to produce an insulated container.

<Example 3 >
In the configuration of FIG. 8, the inner resin layer 3 has a density: 0.936, a melting point: 126 ° C. medium density polyethylene, a thickness of 30 μm,
The paper has a thickness (unit weight) of 300 g / m2, a moisture content of 8%,
A metallocene polyolefin plastomer having a density of 0.870 and a melting point of 53 ° C. as a low-melting resin outside the paper and a low-density polyethylene having a density of 0.921 and a melting point of 110 ° C. as a general-purpose resin are 1: 1. The mixed resin layer (8) mixed at a ratio of 70 μm in thickness
On the outside of the low melting point resin is a low density polyethylene resin layer having a density of 0.918 and a melting point of 106 ° C. and a thickness of 16 μm.
As in Reference Example 1, it was molded into a 300 ml capacity cup in FIG. 2 and then foamed at 120 ° C. for 10 minutes to produce an insulated container.

<Comparative Example 1>
In the configuration of FIG. 5, the inner resin layer 3 has a density: 0.936, a melting point: 126 ° C. medium density polyethylene, a thickness of 30 μm,
Paper 1 has a thickness (unit weight) of 300 g / m 2, a moisture content of 8%,
The outer resin 6 of the paper has a density of 0.918, a melting point of 106 ° C., a low density polyethylene, and a thickness of 70 μm.
As in Reference Example 1, it was molded into a 300 ml capacity cup in FIG. 2 and then foamed at 120 ° C. for 10 minutes to produce an insulated container.

<Comparative example 2>
In the configuration of FIG. 5, the inner resin layer 3 has a density of 0.936, a melting point of 126 ° C., medium density polyethylene, a thickness of 30 μm,
Paper 1 has a thickness (unit weight) of 300 g / m 2, a moisture content of 8%,
The outer resin 6 of the paper has a density of 0.918, a melting point of 106 ° C., a low density polyethylene, and a thickness of 70 μm.
As in Reference Example 1, a cup with a capacity of 300 ml in FIG. 2 was formed, and then a container that was not foamed was prepared.

  270 ml of boiling water at 100 ° C. was poured into the above heat insulating container, a surface thermometer was installed on the outer surface of the container, the change in surface temperature was measured, and the maximum value was measured.

As indicated, when a foam layer using a low-melting point resin is provided, the surface temperature can be kept below 60 ° C., which can be sustained, and the heat of the contents can be sufficiently felt.

  As described above, the heat insulating container using the laminated base paper of the present invention has a surface temperature of 60 ° C. or less even when hot water is put inside, so that the rigidity as the container is maintained and held continuously. It is possible that In addition, the temperature of the contents is slightly felt, and there is appropriate heat conduction that can be noticed when the contents are hot. Therefore, it is difficult to cause accidents that cause the contents to be noticed and burned when the contents are hot. Moreover, since an ordinary extruder lamination machine or dry lamination machine can be used, mass productivity is also good, and the effect of the laminated base paper of the present invention and the heat insulating container using the same is great.

1 ··· Paper 2 ··· Outside resin layer (foamed layer of low melting point resin)
3... Inner resin layer 4... Bottom fused portion 5... Laminated base paper cross-sectional position 6.・ Low melting point resin layer 8 ・ ・ ・ ・ ・ ・ Mixed resin layer 9 ・ ・ ・ ・ ・ ・ Surface resin layer

Claims (4)

In the base paper laminated with synthetic resin on both sides of the paper used for the heat insulating container, polyethylene resin having a melting point equal to or higher than the foaming temperature of the outer resin layer is used as the inner resin layer, and the outer resin layer has a low melting point resin of 100 ° C. or lower. and contain,
An outer resin layer containing a low melting point resin having a melting point of 100 ° C. or lower has a linear low density polyethylene (LLDPE) having a melting point of 100 ° C. or lower, and a low density polyethylene resin (LDPE) having a melting point of 100 ° C. or more on the outside. )
The linear low density polyethylene (LLDPE) having a melting point of 100 ° C. or lower is a metallocene catalyst-based linear low density polyethylene,
The inner resin layer is laminated base paper density 0.936, melting point and wherein the Ru-density polyethylene Tona in the 126 ° C.. In the base paper laminated with synthetic resin on both sides of the paper used for the heat insulating container, polyethylene resin having a melting point equal to or higher than the foaming temperature of the outer resin layer is used as the inner resin layer, and the outer resin layer has a low melting point resin of 100 ° C. or lower. Contains
An outer resin layer containing a low melting point resin having a melting point of 100 ° C. or lower has a linear low density polyethylene (LLDPE) having a melting point of 100 ° C. or lower, and a low density polyethylene resin (LDPE) having a melting point of 100 ° C. or more on the outside. )
The outer resin layer is composed of linear low density polyethylene, ethylene vinyl acetate copolymer resin (EVA), ethylene / methacrylic acid copolymer resin (EMAA), ethylene acrylic acid copolymer resin (EAA), or ionomer resin. A mixed resin containing a low-melting point resin having a melting point of 100 ° C. or lower and a low-density polyethylene resin having a melting point of 100 ° C. or higher, consisting of at least one of polypropylene resin and polybutene resin,
The laminated base paper , wherein the inner resin layer is made of medium density polyethylene having a density of 0.936 and a melting point of 126 ° C. The laminated base paper according to claim 2 , wherein a low-density polyethylene resin having a melting point of 100 ° C or higher is further laminated on the outer side of the outer resin layer composed of the mixed resin. With a lamination sheet according to any one of claims 1 to 3, insulated container, characterized in that imparted sectional heat.