JPH0351220B2 - - Google Patents

Description

[Detailed description of the invention]

"Industrial Application Field" The present invention relates to a method for manufacturing a new laminated sheet for cups and a method for manufacturing cups using the sheet, and more specifically, the present invention relates to a method for manufacturing a new laminated sheet for cups and a method for manufacturing cups using the sheet. A mixture consisting of at least one additive selected from waxes, aliphatic hydrocarbons, polyorganosiloxanes and their derivatives (hereinafter referred to as "water repellent") is laminated and bonded onto a paper base material. The present invention relates to a method for producing a sheet for making a cup, and a method for processing and molding the sheet to produce a cup suitable for hot and cold beverages, particularly for cold beverages that are prone to foaming. ``Prior Art'' ``Problems to be Solved by the Invention'' Conventionally, paper cups impregnated with wax have been widely used as cups for cold drinks such as carbonated drinks. This wax-impregnated paper cup is made by spraying wax such as molten paraffin onto the surface of the cup after the cup is formed to impregnate it, thereby imparting water resistance and strength to the base paper.
However, this wax-impregnated paper cup has problems such as insufficient bending properties, complicated manufacturing process, and poor productivity. On the other hand, paper cups coated with polyethylene are often used as cups for hot beverages such as coffee, but when cold beverages such as carbonated drinks are poured into these polyethylene coated paper cups, a violent foaming phenomenon occurs, causing bubbles and the contents to form. There is a problem with overflowing from the cup. "Means for Solving the Problems" The present inventors have conducted extensive research to solve these problems, and have found that by mixing polyolefin resin with a water repellent and laminating and adhering it onto a paper base material,
The inventors have discovered that the above problems can be solved all at once, and have completed the present invention. That is, the first aspect of the present invention is a method for manufacturing a laminated sheet for cups, which is characterized by laminating and adhering a mixture of polyolefin resin and a specific water repellent onto a paper base material. 2 provides a method for producing a cup, which comprises laminating and adhering a mixture of a polyolefin resin and a specific water repellent onto a paper base material to obtain a laminated sheet, and then processing and molding the laminated sheet into a cup. The content shall be as follows. The water repellent used in the present invention is not particularly limited as long as it is used as a food additive, but examples include petroleum-based waxes such as "microcrystalline wax", "carnauba wax (imported by Kato Yoko Co., Ltd.)", etc. animal and plant waxes, mineral waxes such as "Montan Waxes" (imported by Kato Yoko Co., Ltd.),
Aliphatic hydrocarbons such as polyethylene wax such as “Sunwax (manufactured by Sanyo Chemical Industries, Ltd.)”, “Silicone oil” (manufactured by Toray Silicone Co., Ltd.)
Polyorganosiloxanes such as polyorganosiloxanes and their derivatives include modified silicone resins, and examples include polymethylhydrodiene siloxanes, vinyl group-containing polydimethylsiloxanes, and at least olefins or polyolefins having at least one double bond. Modified silicone resins that are modified to be well compatible with the base olefin resin and to facilitate extrusion lamination, such as reaction products with one type of silicone resin, are suitable. As the olefin resin used in the present invention, any resin that is normally used for lamination bonding can be used, and examples thereof include polyethylene, polypropylene, and copolymers thereof. In the present invention, the blending ratio of the polyolefin resin and water repellent is preferably 99 to 80% by weight of the polyolefin resin and 1 to 20% by weight of the water repellent. If the amount of the water repellent is less than 1% by weight, the effect of adding the water repellent will not be sufficient, while if it exceeds 20% by weight, the melting temperature will be low and the melt viscosity will be lowered, resulting in poor processability. As the paper base material used in the present invention, a conventional cup base paper is used. Laminated adhesive in the present invention refers to extrusion laminate,
Although all known lamination methods such as dry lamination, wet lamination, and film adhesion are included, extrusion lamination is particularly preferred from the viewpoint of production efficiency. In carrying out the present invention, it is preferable to laminate and bond a mixture of a polyolefin resin and a water repellent via the polyolefin resin. As such an intervening polyolefin resin, the same polyolefin resin as mentioned above may be used. Note that it is industrially desirable to perform the above two-layer lamination simultaneously using a two-layer extrusion die. The heat treatment in the present invention is to transfer the water repellent to the surface of the laminated adhesive layer made of polyolefin resin and water repellent on the paper base material and make it unevenly distributed on the surface, and the temperature is room temperature to 120°C. , preferably 30
A temperature of ~70°C and a time of 1 to 60 minutes, preferably 3 to 10 minutes are appropriate. When the water repellent is petroleum-based wax, aliphatic hydrocarbon, etc., the wax or the like becomes unevenly distributed during heat treatment and crystallizes on the resin surface, giving the surface a "lotus leaf" shape, further increasing water repellency. Heat treatment is possible either during the lamination bonding step or after the step. The laminated sheet of the present invention is particularly suitable as a cup for cold beverages, and is also useful as a release material that does not require a high degree of releasability. In order to manufacture a cup using the laminated sheet of the present invention, it is sufficient to perform die cutting and cup forming (processing). In this case, the heat treatment may be carried out at any step from the lamination bonding step to after cup processing and molding. "Examples" The present invention will be described in more detail below with reference to Examples and Comparative Examples, but the present invention is not limited in any way by these. Example 1 Low-density polyethylene "Mirason M16p" (MI 3.7 g/10 min, density 0.923) as polyolefin resin
g/cm ³ , manufactured by Mitsui Polychemicals Co., Ltd.) and 10 parts by weight of polyethylene wax "Sanwax 151p" (molecular weight 2000, degradable wax, manufactured by Sanyo Chemical Industries, Ltd.) as a water repellent were mixed. After that, this mixture is passed through a vented extruder (dice outlet).
260°C), mixed, and pelletized using a pelletizer. After thoroughly drying the obtained pellets at 60°C, they were made into a film using a T-die extruder (diameter 40m/m, T-die temperature 290°C) and made into a cup base paper which had been extruded and laminated with 15μ of 100% polyethylene “Mirason M16p” in advance. (245 g/m ² , manufactured by Chuetsu Pulp Industries Co., Ltd.) 15μ was coated on the polyethylene surface. Three types of the obtained laminated paper were formed into cups as described below and tested for foaming properties: one without heat treatment, one heat treated at 70°C for 10 minutes using a dryer, and one heat treated at 120°C for 10 minutes. . Example 2 A laminated paper was obtained in the same manner as in Example 1, except that polyethylene wax "Hiwax 400p" (molecular weight 4000, polymer type, manufactured by Mitsui Petrochemical Industries, Ltd.) was used as a water repellent. The obtained laminated paper was subjected to the same foaming test as in Example 1. Example 3 Polyethylene wax “LUVAX” was used as a water repellent.
A laminated paper was obtained in the same manner as in Example 1, except that "-1151" (molecular weight 700, manufactured by Nippon Seiro Co., Ltd.) was used. The laminated paper was subjected to the same foaming test as in Example 1. Example 4 Example 1 except that polyorganosiloxane "Silicone Oil SH-200" (viscosity 30000CS/25°C, manufactured by Toray Silicone Co., Ltd.) was used as the water repellent.
A laminated paper was obtained in the same manner as above. The laminated paper was subjected to the same foaming test as in Example 1. Example 5 A: Production of modified silicone water repellent Polymethylhydrodiene siloxane (=
5-7) 6.8 parts by weight, vinyl group-containing polydimethylsiloxane (=150, vinyl group 0.7%) 90.2
parts by weight and 1,2-polybutadiene (“B-
1000'', manufactured by Nippon Soda Co., Ltd., MW=1050) 3
Part by weight was charged into a reactor, heated, and when the temperature reached 120℃, 0.3 parts by weight of di-tertiary butyl peroxide was added as a catalyst, and further heated and reacted at 120℃ for 10 hours to start gelation. At the same time, the reactor was cooled to stop the reaction. The reaction product was purified by removing unreacted volatile components under a reduced pressure of 10 mmHg at 110°C for 12 hours. The silicone content of the obtained purified product was 97.0%. B: Manufacture of laminated sheet for cups As a water repellent, 1 part by weight of the above modified silicone water repellent was mixed with 99 parts by weight of polyethylene in the same manner as in Example 1, pelletized, and dried. Thereafter, it was formed into a film using a T-die extruder to obtain a laminated paper similar to that in Example 1. Next, heat treatment was performed at 120℃ for 10 minutes with the resin side of the laminated paper facing up. After the heat treatment, 2.0 x 10 ^-1 mg/m ² of chloroplatinic acid (IPA solution) was applied on the resin surface and the paper was heated again at 120℃. Curing was carried out at ℃ for 20 minutes, and the same foaming test as in Example 1 was conducted on the obtained laminated paper. Comparative Example 1 A polyolefin resin "Mirason M16p" was extruded without pelletizing to form a film, and the film was coated with 30 μm on cup base paper (245 g/cm ² , manufactured by Chuetsu Pulp Industries Co., Ltd.). The obtained laminated paper was subjected to the same foaming test as in Example 1. Comparative Example 2 Polyolefin resin "Milason M16p" alone was pelletized and filmed in the same manner as in Example 1, and extruded onto cup base paper to obtain laminated paper, and the same foaming test as in Example 1 was conducted. Comparative Examples 3 and 4 As Comparative Example 3, a commercially available wax cup and as Comparative Example 4, a commercially available polyethylene coated hot cup were subjected to a foaming test. Cup molding and foaming test: Each of the above laminated papers was molded into 9-ounce cups using a cup molding machine manufactured by PMC, USA. Next, using the apparatus shown in FIG. 1, carbonated drinking water (Coca-Cola) with a liquid temperature of 10° C. was poured into the resulting cup at a pouring speed of 200 ml/6 seconds to test the foaming properties. The results are shown in Table 1. Evaluation method: As shown in Fig. 2, the foam height was determined by pouring 100 c.c. of carbonated drinking water (Coca-Cola) and measuring the distance between the highest point of the foam and the liquid level. The contact angle was measured by the method described in the 1984 magazine "Kobunshi" Vol. 33, August issue, p. 639.

[Table] "Action""Effects of the Invention" From Table 1, the foaming properties of the cups of the present invention are significantly improved by the use of a water repellent compared to the polyethylene laminated paper cups (Comparative Examples 1 and 2). It is clear that the foaming property is as good as or better than that of the commercially available wax cup (Comparative Example 3). In this way, it is possible to provide a cup that is more efficient in manufacturing than conventional wax-impregnated paper cups, has good bending properties, and is suitable for both hot and cold beverages.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing a foaming property testing apparatus according to the present invention, and FIG. 2 is a schematic diagram showing a foaming property measuring method. 1...Holder, 2...Bottle, 3...Silicone rubber stopper, 4, 5...Glass tube, 6...Kottoku, 7
... Cup, 8 ... Drinking water, 9 ... Sample drinking water (100c.c.), 10 ... Foam, L ... Foam height.

Claims (1)

[Claims] 1 Waxes,
A method for producing a laminated sheet for cups, which comprises laminating and adhering a mixture containing at least one selected from aliphatic hydrocarbons, polyorganosiloxanes and derivatives thereof on a paper base material. 2. The manufacturing method according to claim 1, wherein the mixture is laminated and adhered onto a paper base material via a polyolefin resin layer. 3. The manufacturing method according to claim 1 or 2, wherein heat treatment is performed after the lamination bonding step or the lamination bonding step. 4 Additives to polyolefin resins that have water repellency and are used for food products include waxes,
A laminate sheet is obtained by laminating and adhering a mixture containing at least one selected from aliphatic hydrocarbons, polyorganosiloxanes, and derivatives thereof on a paper base material, and then the laminate sheet is processed and shaped. A method of manufacturing a cup. 5. The manufacturing method according to claim 4, wherein the mixture is laminated and adhered onto a paper base material via a polyolefin resin layer. 6. The manufacturing method according to claim 4 or 5, wherein heat treatment is performed in any step from the laminated sheet manufacturing process to after cup processing and molding.