JPH0361040A - Laminated film and carton - Google Patents

Abstract

PURPOSE:To make a crack hard to generate in a resin layer by constituting a laminated film of a layer composed of poly 3-methyl-1-butene having a specific m.p. and the paper layer provided to one surface thereof. CONSTITUTION:As the paper layer laminated to one surface of a layer composed of poly 3-methyl-1-butene having an m.p. of 220-300 deg.C, paper generally used in the formation of the laminate with a resin such as clay coated paper or milk carton paper is pref. used. The thickness of the poly 3-methyl-1-butene layer is within a range of 1-2000mum and the thickness of the paper layer is 5-5000mum. A laminated sheet can be prepared by directly applying poly 3- methyl-1-butene to paper by extrusion.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a laminated film or sheet formed by laminating a layer made of a specific resin and a layer of paper, and a carton formed from the laminated film or sheet. More specifically, the melting point is 220-3
The present invention relates to a laminated film having excellent oil and fat impermeability, consisting of a layer of poly3-methyl-1-butene at 00°C and a layer of paper, and a carton formed from this laminated film.

Technical background of the invention Recently, cooking methods using microwave ovens have rapidly progressed and become popular.
It has become possible to prepare a wide variety of foods such as dishes and sweets extremely easily.

When cooking food in a microwave oven, a simple container made of a laminate of resin and paper is often used. For example 4-
Food to be cooked is stored in a tray-shaped container formed from a laminated sheet with an inner layer made of methyl-1-pentene polymer and an outer layer made of paper, and the tray-shaped container is placed in a microwave oven.・A cooking method is used in which the whole tray-shaped container is heated using high frequency waves.

Some of the foods that are cooked in the above manner include those that contain oil and fat components such as butter and margarine, such as pound cakes, and those that contain fats and oils such as hamburgers after being heated in a microwave. There are foods that complete cooking by adding seasonings containing oil and fat components, such as sauces. Foods prepared using such cooking methods are often stored in box-shaped containers after being heated in a microwave oven or after being coated with seasonings containing oil and fat components.

However, since the coating layer conventionally made of resin such as 4-methyl-1-pentene polymer is highly rigid, fine cracks may occur in the coating layer. In such cases, the oil and fat components permeate into the paper layer constituting the container over time and ooze out from the paper layer, impairing the appearance of the container and causing problems during handling. , your hands and clothes may become contaminated with oil and fat components.

[1] An object of the present invention is to provide a laminated film or sheet that can be used as a container that can completely prevent penetration of oil and fat components from stored cooked foods, and a laminated film or sheet formed using this sheet or film. is to provide cartons.

Summary of the invention The laminated film according to the invention has a melting point of 220 to 300°C.
a layer (A) made of poly-3-methyl-1-butene; and a paper layer (B) provided on at least one surface of the layer (A) made of poly-3-methyl-1-butene. Consists of two layers.

Further, the carton according to the present invention has the above-mentioned melting point of 220 to 220.
A layer made of poly-3-methyl-l-butene at 300°C (A
) and a paper layer (B) provided on at least one side of the layer (A) made of the poly-3-methyl-butene.

A laminated film consisting of a layer made of poly3-methyl-1-butene having a specific melting point as described above and a paper layer has excellent heat resistance and moderate flexibility.
Cracks are less likely to occur in the resin layer, and cartons formed using such laminated films are made of poly 3-
No oily components penetrate the methyl-1-butene layer into the paper layer.

Detailed Description of the Invention Next, the laminated film and carton of the present invention will be specifically described.

The laminated film of the present invention comprises a layer (A) made of 3-methyl-1-butene and a paper layer (B) laminated on at least one side of the layer (A) made of 3-methyl-1-butene.
) consists of at least two layers.

3-methyl-1-butene used in the present invention is
It has a melting point within the range of 220-300°C, preferably 240-290°C. Poly 3-methyl-1-butene with a melting point of h is produced by copolymerizing 3-methyl-1-butene with an α-olefin.
Alternatively, it can be prepared by changing the type of catalyst used when polymerizing 3-methyl-1,-butene and further changing the conditions during polymerization. Usually, the relationship between these factors and melting point is determined experimentally in advance, and then poly-3-methyl-1-butene having a desired melting point can be produced by conducting polymerization according to the determined conditions. . In this way, 220-30
By laminating a layer of poly-3-methyl-l-butene, which has a relatively low melting point of 0°C, with a layer of paper, the oil and fat components will not penetrate into the paper layer even when heated in a microwave oven, and the container will not accumulate. IW laminated film suitable as a moon
(j', can.

For example, when copolymerizing α-olefins, examples of α-olefins that can be used include ethylene, propylene, l-butene, (-hexene, l-octene, 1-decene, t-tetradecene, i-octadecene). α-olefins having 2 to 20 carbon atoms can be mentioned.

In addition, in the present invention, as 3MB, it is also possible to use modified 3MB in which part or all of it has been modified with an unsaturated carboxylic acid such as maleic anhydride. In this case, modified 3MB can also be used in combination with unmodified 3MB.

In addition, the poly-3-methyl-l-butene used in the present invention may include weathering stabilizers, heat stabilizers, antistatic agents, antifogging agents, antiblocking agents, Compounding agents such as slip agents and colorants can be added.

The paper layer laminated on at least one side of the layer made of poly-3-methyl-1-phthene as described in ``2'' may be paper that is generally used to form a laminate with a resin. can be used. Particularly in the present invention, clay coat paper, milk carton paper, etc., which are usually used as box-making materials, are preferably used. Among these papers, clay 't-1-paper is particularly preferred. By using this clay coated paper, for example, if the poly-3-methyl-1-butene layer of the carton has pinholes or slight cracks due to unexpected external impact or abrasion, or Even if the oil and fat components penetrate from the end faces of the laminated sheet, there is an advantage that the penetration of the oil and fat components is extremely slow. Furthermore, since this clay coated paper has excellent printability, it is also a suitable printing base material when forming a printing layer on the outer surface of the container as required.

The laminated film of the present invention only needs to be provided with a paper layer (B) on at least one surface of the layer (A) made of poly3-methyl-(-butene as described above). The film consists of the above (A) layer and (B) layer.
In addition to the layer film, there are two layers (A) sandwiching the (B) layer.
) layer, a three-layer laminate with two (B) layers sandwiching the (A) layer, (A)
It may be a laminate of four or more layers in which the layers and the (B) layers are alternately laminated.

In the laminated film of the present invention, the thickness of the poly-3-methyl(-butene layer can be set appropriately, but it is usually in the range of 1 to 2000 μm, preferably 5 to 50 μm, and the thickness of the paper layer is Thickness is usually 5 to 5000 μm
1 preferably within the range of 100 to 600 μm. Therefore, the laminated film of the present invention includes what is called a film-like film and a sheet-like film.

The laminated sheet of the present invention is, for example, on the above paper,
It can be produced by direct extrusion coating of poly-3-methyl-1-butene. In this case, in order to further increase the adhesive strength between the poly-3-methyl-1-butene layer and the paper, an anchor coating agent such as organic titanium, polyethyleneimine, or isocyanate is applied to the surface of the paper. After forming an undercoat layer using a known method, such as a method of forming an undercoat layer using adhesive polyolefin, a method of forming an undercoat layer made of adhesive polyolefin, high-pressure polyethylene, etc., 3-methyl-1-butene is extruded. It can also be coated. In this case, a laminated sheet consisting of three layers will be constructed.

In the present invention, poly-3-methyl-1-
Butene has excellent extrusion coating properties at high speeds, so it can be extrusion coated at high speeds using ordinary extrusion coating processing equipment, which improves mechanical properties and interlayer adhesion. An excellent laminated sheet can be obtained. When extrusion coating is performed in this way, by blowing gas such as air or nitrogen gas onto both ends of the film-like material, neck-in and ear wobbling at both ends of the film-like material can be improved. The position where the gas is sprayed is 3-methyl-1-
It is preferable that the gas be blown from the side where the film made of butene is in contact with the base material (paper layer) and not on the side where the film is in contact with the base material. By doing this, −
Extrusion coating can be carried out in a stable layer state and at high speeds.

When the above method is adopted, the method of blowing gas onto the film is to place a conduit such as a metal pipe such as an aluminum pipe or a steel pipe, or a thermoplastic resin pipe downstream of the die, and chain it. There is a method in which gas is blown from a tube at any position between the poly-3-methyl-1-butene film extruded from the die and in contact with the base material, preferably near the contact point where the film-like material is coated on the base material. Can be mentioned. Is the pressure of zero gas when spraying adjusted appropriately, taking into consideration the thickness of the film-like material to be coated? i; 0.5~5kg/cJ G
is within the range of The diameter of the tip of the nostle for spraying is usually in the range of 1 to 50 mm2, preferably 5 to 10 mm2. Also, the distance from the tip of the nozzle to the film is
It is usually in the range of 2 to 100 mm, preferably 5 to 20 mm. Furthermore, it is preferable to direct the tip of the nozzle from the center of the film toward the outer edge, since the blown gas expands the film-like material and further increases the effect of narrowing the neck-in.

In the present invention, the extrusion temperature when extrusion coating poly-3-methyl-1-butene on the group H is usually 250 to 370°C.
Preferably, it can be carried out at a temperature within the range of 290 to 340°C. Further, the extrusion coating speed (coating material take-off speed) can be set at 40 m/min or more, preferably in the range of 150 to 500 m/min.

The carton of the present invention is formed using the above laminated film.

1. In the car I/N of the present invention, the above interlayer film (F) is placed so that the layer (A) made of poly 3-methyl-(-butene described in 2) becomes the side that comes into contact with food, that is, the inner layer. It is preferable to use

There are no particular limitations on the shape or manufacturing method of the carton of the present invention. Therefore, the carton of the present invention can be manufactured by molding the above-mentioned laminated film into a desired shape using a known method.

The thus obtained carton of the present invention can be used in the same manner as conventional cartons.

Effects of the Invention According to the present invention, since a laminated film consisting of a poly-3-methyl-1-butene layer with a low melting point of 220 to 300°C and a paper layer is used, poly-3-methyl-1-butene Penetration of oil and fat components from the layer side is completely prevented, and the sheet made from this laminated sheet exhibits excellent bending resistance, so it can be used as a tray for cooking in a microwave oven, as well as for cakes and pastries. Suitable for use as packaging containers and cartons for foods containing oil and fat components such as
2 I can do it.

Example The present invention will be described in detail below based on examples.

Note that the melting point and MFR1 initial bending modulus in the examples were measured by the following method.

The melting point in the present invention is determined using a differential scanning calorimeter (Model
DSC-U (manufactured by PerkinElmer), the sample was
After melting at 20°C for 1 minute, it was cooled to room temperature at a rate of 20°C/1 minute to crystallize, and after keeping this sample at room temperature for 1 minute, the endothermic curve was measured at a heating rate of 106C/1 minute. This is the peak temperature of the case. In the poly-3-methyl-butene used in the present invention, a plurality of endothermic peaks may be detected, in which case the highest peak temperature is taken as the melting point.

MFR: According to ASTM D 1238, load 5
kg was measured at 320°C.

Initial bending modulus: Measured according to ASTM D 790.

(However, the test speed was 5 mm/min.) -3 Example 1 3-Methyl- with melting point 270°C, MFR; 26 g/lo min, initial bending modulus 14000 kg/c+]
A crystalline copolymer of 1-butene and 1-decene (1-decene content: 6% by weight) (hereinafter referred to as 3MB (I)) was melted in an extruder with a diameter of 65 mm, and the mass was 290 g/
Lamination 1 and molding were performed on RRF milk carton paper.

The coating thickness of 3MB (I) was 20 μm.

From the obtained laminated paper, make sure that the inward side is the coat layer], OcmX i OcmX 5cm (depth)
A box (carton) was created.

40 g of commercially available margarine (manufactured by Snow Brand Milk Industry ■) was weighed, placed in the carton prepared as described above, and heated for 30 seconds in a microwave oven (manufactured by Matsushita Electric Industrial ■; type NE-A740). After heating, the paper layer was allowed to stand at room temperature, and the number of bites until margarine oozed out to the outer surface of the paper layer was visually determined.

Further, using the same carton as above, powdered chocolate cake (manufactured by House Range Gourmet, House Foods ■) and water were added and cooked in the same microwave oven for 3 minutes and 30 seconds. After cooking, when the contents were taken out, it was observed whether the contents oozed out to the outside.

Using the same box as above, powdered butter cake (manufactured by House Range Gourmet, House Foods ■) and water were added, and the mixture was cooked in an oven at a set temperature of 190'C for 20 minutes. After cooking,
Without removing the contents, it was observed whether the contents oozed out to the outside.

The results are shown in Table 1.

Example 2 Instead of 3MB (1) used in Example 1, melting point 2
Crystalline copolymer of 8-methyl-1-butene and 1-decene (l-decene content 4
A laminated film was manufactured in the same manner as in Example 1, except that 3MB (% by weight) (hereinafter referred to as 3MB (II)) was used, and a carton was manufactured in the same manner as in Example 1, except that this laminated film was used, and its performance was evaluated. did.

The results are shown in Table 1.

Comparative Example] Instead of 3MB (1) used in Example 1, 3-methyl-l-butene homozygous with melting point 31-0°C, MFR; 40 g/l, 0 minutes, initial bending modulus 2 BOOO kg/c A laminated film was manufactured in the same manner as in Example 1 except that a polymer (hereinafter referred to as 3MB (H)) was used, and a carton was manufactured in the same manner except that this laminated film was used, and its performance was evaluated.

The results are shown in Table 1.

Comparative Example 2 Instead of 3MB (I) used in Example], melting point 3
05℃SMFR40g, initial bending modulus 22000k
g/cJ of a crystalline copolymer of 3-methyl-1-butene and 1-decene (1-decene content: 2% by weight) (hereinafter referred to as 3M
A laminated film was manufactured in the same manner as in Example 1 except that B (referred to as B (III)) was used, and a carton was manufactured in the same manner except that this laminated film was used, and its performance was evaluated.

The results are shown in Table 1.

6

Claims (3)

[Claims] (1) Poly-3-methyl-1- with a melting point of 220 to 300°C
A laminated film consisting of at least two layers: a layer (A) made of butene and a paper layer (B) provided on at least one surface of the layer (A) made of poly3-methyl-1-butene. . (2) Layer made of the above poly-3-methyl-1-butene (A
2. The laminated film according to claim 1, wherein the thickness of the paper layer (B) is within the range of 1 to 2000 μm, and the thickness of the paper layer (B) is within the range of 5 to 5000 μm. (3) Poly-3-methyl-1- with a melting point of 220-300°C
A laminated film consisting of at least two layers: a layer (A) made of butene and a paper layer (B) provided on at least one surface of the layer (A) made of poly3-methyl-1-butene. carton which is formed from.