JPH0515894Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Field of Application] The present invention relates to inner sheets of containers used for storing and transporting rice, and is designed to prevent rice from getting wet by trapping steam that tends to adhere to the inner wall of the container and condense. This relates to a sheet that can prevent this. [Prior Art] Recently, cooked rice has been sold as a product by rice-cooking specialists to schools, hospitals, various public organization cafeterias, school lunches, bento boxes, restaurants, hotels, inns, etc. (hereinafter referred to as consumers). It's starting to look like this. In other words, rice cooking was originally supposed to be done by individual food and beverage businesses, but under the following circumstances, businesses that specialize in rice cooking take over the task and sell the rice as a product. It is rapidly increasing. Improving and stabilizing the taste The taste of rice varies slightly depending not only on the type of rice and storage period, but also on water quality, water amount, water temperature, heating rate during cooking, holding temperature, etc. It is not always possible to cook the best rice depending on the quality of the rice. However, by making rice cooking an independent specialty, central control becomes possible and a stable supply of high-quality rice becomes possible. Improving the efficiency of rice cooking equipment and rice cooking work From the customer's perspective, rice cooking equipment and work space in the kitchen are no longer necessary, which not only increases the overall work space, but also eliminates the need for rice cooking work at all, making it possible to use specialized equipment. You can concentrate on cooking work. Eliminates the problem of wastewater pollution When cooking rice, a large amount of organic wastewater is generated from washing the rice and washing it in a pot, but the reality is that this is disposed of untreated by individual restaurant operators. Causes water pollution. However, if the rice cooking work is carried out intensively by a rice cooking specialist, it will become possible to purify the organic wastewater generated in large quantities, and the problem of water pollution will be resolved. By the way, rice cooked by a rice cooking specialist is packed into transportation containers and promptly delivered to consumers, but the most important thing here is how to prevent the deterioration of the rice during storage and transportation.
The issue is whether the food should be delivered in a state that retains its freshly cooked taste. Under such conditions, the biggest factor that reduces the taste of rice is water wetting due to dew condensation.
That is, since cooked rice is hot and contains a large amount of water, a large amount of steam is generated. Therefore, even if considerable heat insulation measures are taken, the generation of condensed water due to the temperature difference with the outside air is unavoidable, and the generation of condensed water lowers the partial pressure of water vapor in the gas phase inside the container, so new steam is generated and the steam A vicious cycle of generation → condensation → steam generation results in an increase in condensed water. If this condensed water collects on the side walls or bottom of storage containers or transportation containers,
The rice in this area will be wet. This causes the product to swell and become sticky, become lumpy, and deteriorate in taste, and sometimes bacterial growth begins, causing the product to lose its commercial value in a short period of time. [Problem to be solved by the invention] The present invention was made with attention to the above-mentioned circumstances, and its purpose is to create a container used for storing or transporting food for business use, boxed lunches for home use, etc. An inner sheet that can effectively prevent rice from getting wet due to dew condensation, prevent the above-mentioned undesirable development due to water wetting, and maintain the good taste of rice for a long time. This is what we are trying to provide. Furthermore, the present invention can be applied to a wide range of rice such as white rice, red rice, seasoned rice, and sushi rice. [Means for Solving the Problems] The inner liner sheet according to the present invention, which has solved the above problems, combines a water-absorbing member in which a water-absorbing polymer substance is attached and scattered on the fibers of a fiber mat layer with a water-permeable thin film and a non-woven material. The gist is that it is interposed between water-permeable thin films. In this case, if a water-retaining structural layer is laminated on the water-permeable thin film side, the water-retaining structural layer will function as a supersaturated water-retaining layer, improving the water-retaining performance of the inner sheet as a whole, and preventing rice from getting wet. The prevention effect will be even better. [Function] The basic laminated structure of the inner sheet according to the present invention is as shown in Figures 1 to 4 (schematic cross-sectional diagrams), in which 1 is a water-permeable thin film, 2 is a water-absorbing member, and 3 is a non-woven material. A water-permeable thin film, 4 indicates a water-retaining structure layer. In its use, the water-impermeable thin film 3 is placed on the inner wall of the rice container and lined inside the rice container. First, the inner sheet shown in Fig. 1 has a water permeable thin film 1 laminated on one side with a mat-shaped water absorbing member 2 (detailed structure is shown in Figs. 5 and 6) in between, as shown in the figure, and a water permeable thin film 1 on the other side. It is constructed by laminating water-impermeable thin films 3. In addition, the inner sheet shown in Figs. 2 to 4 is the water absorbing member 2.
It is constructed by laminating a water-retaining structure layer 4 and a water-permeable thin film 1 and a water-impermeable thin film 3 on top and bottom thereof. Next, the functions and materials of each constituent layer will be explained. The water-permeable thin film 1 allows water to permeate in the direction of the water-absorbing member 2, and also serves as a separator to prevent the water-absorbing member 2 or the water-retaining structure layer 4, which has a weak structural strength, from adhering to the rice and being peeled off and mixed into the rice. It functions as a mold layer, and includes, for example, woven fabrics, knitted fabrics, nets, etc. made of natural fibers or synthetic fibers, and slit-shaped, circular, rectangular, etc. holes of appropriate size at appropriate intervals. Synthetic resin films (polyolefin films such as polyethylene and polypropylene, nylon films, polyester films, etc.) are used. The water-absorbing member 2 is a main component that prevents rice from getting wet due to condensation water, and has a structure in which a water-absorbing polymeric substance is attached and scattered on the fibers of a fiber base material. absorbs moisture that has entered from the water-permeable thin film 1 side and prevents the moisture from returning to the rice side. Such water absorbing member 2
For example, a water-absorbing polymer substance is supported on a fiber mat such as paper, nonwoven fabric, or woven fabric made of synthetic fibers or natural fibers in an adhered state. this is,
For example, it is manufactured by the following method. After applying an aqueous solution of a polymerizable monomer or a polymerizable monomer containing a partially crosslinked oligomer to the fiber mat by spraying, impregnation, coating, etc., a crosslinking agent is further added if necessary to form the fibers of the fiber mat. A method of manufacturing by polymerizing and integrating the above. After applying an aqueous solution of a linearly polymerized prepolymer to which a crosslinking agent has been added to the fiber pine by spraying, scattering, impregnating, or coating, the prepolymer is crosslinked and the fiber pine is coated. A method of manufacturing by integrating fibers and water-absorbing polymeric substances. A method of manufacturing by attaching separately manufactured granular water-absorbing polymeric substances to fiber mats by impregnation or coating using a natural, semi-synthetic or synthetic adhesive. In any of these methods, the fifth
As shown in the figure, a fiber mat with a water-absorbing polymer substance unevenly supported mainly on one side, or a fiber mat with a water-absorbing polymer substance supported over the entire fiber mat as shown in Figure 6. can be obtained. When using the water-absorbing member 2 shown in FIG.
The a side is the water-permeable thin film 1 side or the non-water-permeable thin film 3 side.
The object of the present invention can be achieved no matter which side is stacked. Preferred examples of polymerization components used here include acrylic acid (salt), acrylonitrile, acrylic ester, and vinyl alcohol. When polymerized, graft polymerization of these polymer components proceeds starting from active moieties such as active hydrogen present in the fiber constituent molecules, and a water-absorbing fiber mat is suitably obtained. In the present invention, a water-absorbing polymeric substance is attached and scattered on the fiber mat layer, so that all of the polymeric substance participates in water absorption and a high water-absorbing ability is exhibited. As mentioned above, the water-absorbing polymeric substance is attached to the fibers constituting the fiber mat, and even if it absorbs a large amount of water, the absorbed polymeric substance will not move due to vibration or the like. The non-water-permeable thin film 3 has the function of preventing moisture and bacteria adhering to the container wall from entering the container after the container has been cleaned. Polyolefin film, nylon film, polyester film, etc.) or paper or cloth impregnated with or laminated with a water-impermeable resin to make it water-impermeable are used. Moreover, the water retention structure layer 4 used in FIGS. 2 to 4 is
While ensuring a path for moisture to migrate in two directions of the water absorbing member, the water absorbing polymer material expands due to water supply and prevents new moisture from entering.This prevents rice from getting wet. The material for the main layer 4, which has a more reliable blocking function, may be, for example, a non-woven fabric made of synthetic or natural fibers,
Absorbent cotton, bulbs, or foamed resin with open cells are used. The lamination position of the water retaining structure layer 4 may be anywhere as long as the water permeable thin film 1 is between the water impermeable thin films 3 as shown in FIGS. 2 to 4. In order to improve the integrity of the laminate obtained by overlapping these materials, it is preferable to apply embossing, heat sealing, or the like. When the liner sheet configured in this manner is lined on the inner wall of a rice container, water vapor or condensed water present on the rice charging side A enters through the water-permeable thin film 1 and is absorbed by the water-absorbing member 2, and the water-retaining member 2 absorbs water. structural layer 4
If there is an intervening layer, water enters the water absorption member 2 direction through this layer and is absorbed. Since moisture is captured by the water-absorbing polymer material in the water-absorbing member 2,
There is no risk that water will return to the rice side and cause it to get wet. Furthermore, when the water-absorbing member 2 is used in combination with the water-retaining structure layer 4, even when the weight of rice is applied to the sheet with the water-absorbing amount of the water-absorbing member 2 saturated, the water-retaining structure layer functions as a water-retaining layer. ,
It is possible to more reliably prevent rice from getting wet. In addition, a water-impermeable thin film is placed on the back side of the water-absorbing member 2, which prevents moisture from washing the container or microorganisms from remaining food residue due to insufficient washing from migrating to the rice side. can do. Therefore, even when this container is used, for example, as a returnable box, no hygiene problems arise. When the inner sheet of this invention is used in this way,
Wetness due to condensation can be prevented as much as possible, but especially by using a special water absorbing member with a water absorbing polymer material adhering to it, or by using it in combination with a water retaining structure layer. The following effects are exhibited. Since the water-absorbing polymer substance is adhered and supported on the fiber mat layer as a water-absorbing member, there is a risk that the water-absorbing polymer substance will move due to vibrations etc. when handling the inner sheet material and the dispersion state will become uneven. Since the water-absorbing polymer substance is dispersed and adhered to the fiber mat layer, the water-absorbing effect is evenly exhibited over the entire surface of the sheet. When a water-retaining structure layer is used in combination with a water-absorbing member, even if the water-absorbing polymer substance swells during the process of saturation of the water-absorbing member, a new path for water to enter is secured, and backflow of water is prevented. Ru. [Example] Example 1 A 30% by weight aqueous solution of a water-soluble monomer mainly composed of sodium acrylate was sprayed on one side of a polyester nonwoven fabric, polymerized using a polymerization initiator, and then dried to form a nonwoven fabric. A water-absorbing member was obtained in which a water-absorbing polymer substance was adhered and supported on one side of the water-absorbing member. Next, from the top layer, a polyethylene film with 1 cm long slits provided at 1 cm intervals, crepe paper, the water absorbing member with the water absorbing polymer material side facing up, and then a polyethylene film were stacked in that order to form an inner sheet. Obtained. Polypropylene food can (300 ^W × 300 ^L × 180 ^H mm)
The inside of the inner sheet was placed with the slit film side facing inside, cooked rice was placed inside, the lid was covered, and the rice was left at room temperature (25°C). After 15 hours had elapsed, we observed the condition of the rice and found that none of the rice in the can was sticky or lumpy; it remained in good condition, had no strange odor, and was delicious. It didn't change. Furthermore, when we measured the moisture content of the rice in each part of the food can, we found that a desirable moisture content of around 65% was uniformly maintained within the food can, as shown in Table 1.

[Table] Comparative Example 1 An experiment was conducted in the same manner as in Example 1, except that only a polyethylene film bag without holes was placed inside the food can. As a result, the rice on the four sides and bottom of the food can became sticky or lumpy, resulting in a significant decrease in product value. In addition, when we measured the moisture content of the rice in each part of the food can, we found that, as shown in Table 1, the moisture content of the rice varied considerably depending on its location due to condensation, resulting in an uneven state. Shown. [Effects of the invention] The invention is constructed as described above, and since water condensation does not occur, the taste of the rice can be kept good, and bacteria from washing water and dirt on the container wall are removed from the sheet. Since the rice does not get inside the container, even if the container is not washed or dried enough to be used as a returnable box, the rice will not be contaminated. Since it is inexpensive, there is little economic burden even if it is disposable, and it is easy to handle.In addition to the effects described above, it is possible to obtain the effects shown above.

[Brief explanation of the drawing]

1 to 4 are schematic cross-sectional explanatory diagrams showing an embodiment of the present invention, and FIGS. 5 and 6 are schematic cross-sectional explanatory diagrams of a water absorbing member 2 used in the present invention. 1...Water permeable thin film, 2...Water absorbing member, 3...Water impermeable thin film, 4...Water retaining structure layer.

Claims (1)

[Claims for Utility Model Registration] (1) A water-absorbing member in which a water-absorbing polymer substance is attached and scattered on the fibers of the fiber mat layer is interposed between a water-permeable thin film and a water-impermeable thin film. Lining sheet for rice containers. (2) A water-absorbing member in which a water-absorbing polymer substance is attached to the fibers of the fiber mat layer and a water-retaining structure layer are laminated, and these are placed between a water-permeable thin film and a non-water-permeable thin film, and the water-retaining structure layer is placed on the water-permeable thin film side. An inner liner sheet for a rice container, which is characterized by being interposed with a lining sheet.