JPS6259666B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel sheet with immobilized chemical agents.

When powdered chemical agents are used for various purposes by utilizing their chemical and physical effects, it is convenient to immobilize them on sheets in advance because they are fluid. is often the case. In order to immobilize a powdered chemical agent on a sheet, it must first be dissolved in a solvent to form a solution.
There is a method of impregnating this into a porous base sheet such as paper and then drying it, or a method of mixing it into a coating agent and applying it to the surface of the base film. However, in these methods, there is a problem that the bonding force of the chemical agent to the base film is weak and the chemical agent easily peels off from the base film, and a large amount of coating is required to increase the bonding force to the base film. If a chemical agent is used, there are problems such as the reactivity of the chemical agent being significantly impaired.

The present invention differs from such conventional methods in that it is intended to firmly immobilize chemical agents by filling and retaining them in recesses formed on the surface of the base film.

That is, according to the present invention, a fibrous film layer B (X) is interposed on the surface of a chemical agent layer A formed by filling a chemical agent into the recesses of a base film having recesses formed on the surface, thereby improving air permeability. There is provided a sheet on which a chemical agent is immobilized, characterized in that it has a structure in which plastic films B(Y) are laminated.

Next, the present invention will be explained with reference to the drawings. Fig. 1 shows a cross-sectional structure of a chemical agent layer in which a chemical agent is filled and fixed in the recesses of a base sheet. In the figure, 1 is the base film, and 2 is the recess. , 3 shows the chemical agent filled and held in the recess. Figure 1a shows an example of a chemical agent layer formed by filling and retaining a chemical agent in the recesses of a base film that has recesses only on the front surface and a smooth surface on the back side. An example of a chemical agent layer formed by filling and retaining a chemical agent in the recesses of the base material obtained by molding the base material into a corrugated or core structure and FIG. 1c shows the base film having holes 5 as shown in FIG. An example of a chemical agent layer formed by using a porous film and filling and retaining a chemical agent into recesses formed on both sides of the film is shown. The recesses can be formed in the base film by embossing or other conventional methods.

As the base film 1, sheets or film-like materials (hereinafter simply referred to as films) made of various materials are used, such as polyethylene, polypropylene, polybutadiene, polyvinyl chloride, polystyrene, polyacrylate, polyamide, polyester, melamine resin, and phenol. Plastic films such as resins and cellophane, films made by blending these plastic films with inorganic fillers, fibrous films such as paper, cardboard, nonwoven fabrics, woven fabrics, and nets, metallic films such as aluminum foil, and wood films. can be mentioned.

The thickness of this base film is not particularly limited and can be varied depending on the use of the sheet of the present invention. For example, the thickness of this substrate is 20-500
μ or more, but when the sheet of the present invention is used as a gas adsorption sheet, it is usually selected from the range of 50 to 200 μ. In addition, the dimensions of the recesses formed in these base materials are not restricted and are arbitrary, but generally the length is 50 μm.
Selected from the range of ~2cm. When using the sheet of the present invention as an adsorption sheet, the dimensions of the recesses should be as small as possible; for example, the length should be 50μ to
It is better to set it to 200μ. Moreover, the shape of the recess formed in these base materials is also arbitrary, and can be made into various shapes such as circular, square, and triangular. Furthermore, when fibrous materials are used as the base material 1 in the present invention, it is preferable to laminate a plastic film on these fibrous materials to improve moldability. The filling of the chemical agent 3 into the base material recess 2 is as follows:
The chemical agent can be used in the form of granules or in the form of a paste.

The distribution shape of the recesses 2 in the base material 1 is arbitrary, and fine recesses may be uniformly distributed over the entire surface,
By distributing minute depressions in blocks on the surface,
Alternatively, coarse recesses can be distributed at regular intervals. Furthermore, the recesses to be distributed can be formed into a suitable shape or pattern on the surface of the base material, for example, in the shape of concentric circles.

In the present invention, the chemical agent to be filled into the recesses 1 of the base film A is usually in powder form, but in some cases, a liquid itself may be used. In the case of a liquid, it is preferable to adsorb or absorb it into a porous filler before filling it. In this case, it is preferable that the adsorption amount of the liquid to the filler be equal to or less than the saturated adsorption amount of the filler.

Chemical agents advantageously applied in the present invention include:
Various gas adsorbents such as oxygen scavengers, desiccants, and deodorizing agents, enzymes, various physiologically active substances, various indicators or diagnostic agents, heavy metal scavengers, decolorizing agents, ion exchange resins,
Liquid crystals, microencapsulated products of various unstable substances such as enzymes and liquid crystals, volatile insect repellents and deodorants, fragrances, and other adsorbent, reactive, or volatile chemical agents are used.

The sheet of the present invention has a structure in which a breathable plastic film B(Y)B with a fibrous film layer B(X) interposed on the surface of such a chemical agent layer A is laminated, and the sheet is in contact with the film B. It is characterized in that gas or liquid can pass through this film B and come into contact with the chemical agent layer A. In this case, examples of the fibrous film B(X) include rayon paper, thin paper, nonwoven fabric, pure white paper, and parchment paper. These fibrous films B(X) are preferably used in the form of a laminate with a perforated plastic film or the like in order to increase its strength. Films that have only air permeability and virtually no liquid permeability include films that are made by applying a coating agent such as a water repellent to the surface of a fibrous film or perforated plastic film to form a thin film on the surface. Alternatively, a water-repellent fibrous film such as parchment paper or a film obtained by sandwiching a water-repellent fibrous film between two perforated plastic films is used.

FIG. 2 shows an explanatory sectional view of the sheet of the present invention.

In the laminated sheet of the present invention, a fibrous film layer B is provided on the surface of the chemical agent layer A as shown in FIG.
A laminated sheet having a laminated structure (X) and a layer B (Y) of an air permeable plastic film (hereinafter also referred to as perforated plastic film) having pores on its surface provides a laminated sheet that is extremely advantageous in terms of use. That is, the fibrous film layer B interposed between the perforated plastic film layer B (Y) and the chemical agent layer A
Since (X) is highly porous and relaxes the bond with both layers B(X) and A, the gas that permeates through the perforated plastic film layer B(Y) is absorbed by this fibrous film layer B(X). ) easily diffuses and comes into contact with the chemical agent in the recesses of the base film, and conversely, the vapor emanating from the chemical agent easily diffuses into the fibrous film layer B (X) and the perforated plastic film layer. It passes through B(Y) and is emitted to the outside of the sheet. Furthermore, the gas permeability from the outside of the sheet to the chemical agent layer in this case is proportional to the number of pores or the size of the pore area existing in the perforated plastic film layer B (Y). By increasing , the gas permeability to the chemical agent layer A can be increased. Moreover, a fibrous film layer B interposed between these two layers A and B (Y)
By making the property of (X) hydrophilic,
On the other hand, by making the material hydrophobic, it becomes possible to substantially prevent water permeation.

In the sheet on which the chemical agent of the present invention is immobilized, in order to increase the mechanical strength of the sheet, various types of films, such as plastic films, etc. Aluminum foil or the like can be laminated, and in order to provide heat sealability, a plastic film with good sealing properties such as polyethylene film can be laminated. FIG. 3 shows an example in which various film layers are laminated on the lower surface of the chemical agent layer A. Figures 3a-b show an example in which an impermeable film C (e.g. non-porous plastic film or aluminum foil layer) is laminated on the lower surface, and Figure 3c shows the upper surface of the chemical agent layer A in Figure 1c. , shows a sheet in which a fibrous film layer B (X) and a perforated plastic film layer B (Y) are similarly laminated on the lower surface, making the entire sheet breathable or liquid permeable.

When creating the laminated sheet in the present invention, various conventionally known methods are applied to bond each layer.
For example, a method using a liquid adhesive, a method that utilizes the heat-sealing property if one of the layers to be bonded is heat-sealable, or a method that uses a heat-sealable layer in advance as a bonding layer on one side of the film to be laminated. There are ways to keep them connected.
When bonding each layer, it is necessary to take care not to impede the air permeability or permeability between the layers, and for this purpose, an adhesive layer or heat seal formed on the film surface to be laminated is required Make the layer thin. When each layer is crimped with such a thin bonding layer interposed, the bonding layer formed between each layer becomes discontinuous and exhibits appropriate air permeability or air permeability. In order to obtain a strong bonding layer, it is preferable to bond each layer through a heat-fusible film having good air permeability, such as perforated polyethylene.

When producing a sheet on which a chemical agent is immobilized according to the present invention, the material and laminated structure of the laminated film are appropriately selected depending on the type of agent to be immobilized. For example, in a sheet on which a chemical agent is immobilized, when a gas adsorbent such as an oxygen absorber, a desiccant agent, or a deodorizer is used as the chemical agent, for example, by using the structure shown in FIG. 3c,
It is possible to obtain a gas adsorption sheet that can perform gas adsorption from both sides.
By having the structures shown in figures a to b, an adsorption sheet that adsorbs gas from one side can be obtained. The latter adsorption sheet that adsorbs gas from one side is advantageously used as a packaging material. That is, in this case, two of the sheets are stacked with the breathable film layer B(Y) on the inner surface, and three sides thereof are joined to form a packaging bag. Then, when an article is put into the opening of the bag and the bag is sealed, an article package is obtained in which the target gas is adsorbed and removed from the internal space by the adsorbent.

Further, when a heavy metal scavenger or an ion exchange resin is used as the chemical agent, a filtration material for heavy metal capture or ion exchange treatment can be obtained by using the structure shown in FIG. 3c. Furthermore, when an indicator is used as a chemical agent, by using a transparent material as the base film 1 and having the structure shown in FIG. 2, an indicator sheet can be obtained in which the discoloration of the indicator can be seen through the back side of the film. Can be done.

In any case, according to the present invention, various chemical agents can be immobilized in the manner described above, and, for example, enzymes, liquid crystals, fragrances, etc. immobilized in sheet form can be easily obtained. In this case, the chemical agent has the advantage that its immobilization is strong and its physical action and reactivity are not impaired.

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 A large number of recesses with a diameter of about 2 mm and a depth of about 100 μm were formed on the surface of a polyethylene film with a thickness of 120 μm as a base material, and the particle size was
Oxygen scavenger (iron powder treated with dilute hydrochloric acid) of 100μ or less is distributed and pressed with a roll to fill the recesses with the oxygen scavenger. After removing the excess deoxidizing material remaining on the surface, thin paper is layered on the surface, and a 40μ thick perforated polyethylene film is layered on top of that, and the whole is bonded under heat and pressure to form an integrated sheet. The sheet thus obtained has the property of reacting with oxygen in the air and is used as an oxygen absorbing sheet. In addition, this oxygen absorbing sheet has a nylon film bonded to its underside under heat.
Applied as an oxygen-absorbing packaging material with increased strength.

Example 2 In Example 1, fine particulate silica gel is used instead of the oxygen scavenger to obtain a laminated sheet in which the recesses are filled with silica gel. This product is used as a dehumidifying sheet or a deodorizing sheet.

Example 3 Polyethylene film with a thickness of 150μ and a pore diameter of approximately 0.3
A recess with a diameter of about 2 mm and a depth of about 100 μm is formed in a base film with good liquid permeability, which is formed by punching a large number of holes of mm in size, and the recess is filled with zeolite powder. Layer and glue thin paper with perforated polyethylene film attached to the surface. This sheet has air permeability and liquid permeability, and is used as a sheet for deodorizing and dehumidifying gas, as well as a sheet-like filtration material for collecting metal ions from solutions.

[Brief explanation of the drawing]

1a-c are cross-sectional illustrations of the chemical agent layer;
The figure is a cross-sectional explanatory diagram of an example in which a breathable film layer is laminated on the surface of the chemical agent layer, and Figures 3a to 3c are cross-sectional views of an example in which a breathable film layer is laminated on the surface of the chemical agent layer, and various types of layers are further applied to the back side. An explanatory cross-sectional view of an example in which film layers are laminated is shown. A... Chemical agent layer, B (X)... Breathable fibrous film layer, B (Y)... Perforated plastic film layer, C... Non-breathable film layer, 1... Base film, 2... ...Recess, 3...Chemical agent, 5...
Hole.

Claims (1)

[Claims] 1. A breathable plastic film layer B (Y) is laminated on the surface of a chemical agent layer A formed by filling a chemical agent into the recesses of a base film having surface recesses via a fibrous film layer B (X). An immobilized sheet of chemical agents with a structured structure.