JP2915920B2 - Water absorbing sheet with functionality - Google Patents

Description

The present invention relates to a functional water-absorbent sheet, and more particularly to a material for keeping freshness of fresh food, sanitary products, diapers, disposable rags, paper towels and the like. The present invention relates to a water-absorbing sheet having a specific function that is useful as a material of a product requiring water absorption.

[Conventional technology]

BACKGROUND ART Conventionally, super-water-absorbing resins have been widely used as materials for freshness-keeping materials for fresh foods, sanitary products, diapers, disposable rags, paper towels and the like.

For fresh food, to preserve its freshness. Conventionally, various measures have been taken, but in particular, free water leaching from fresh foods such as meat, seafood, etc., significantly reduces the freshness of the food, so that the free water can be immediately removed. It is an important factor indispensable for maintaining freshness.

Conventionally, as a countermeasure against free water, a method of storing a water-absorbent sheet using a superabsorbent polymer material in a packaging form of fresh food and removing the free water by absorbing water is known as a prior art.

For fruits and vegetables such as fruits and vegetables,
Freshness is reduced due to ethylene gas generated from fruits and vegetables or condensation of water vapor due to respiratory action in a sealed state such as bagging or similar state.

Conventionally, in order to prevent such a decrease in freshness of fruits and vegetables, for example, during transport of fruits or vegetables packed in a box or bag with two types of freshness retaining materials such as a water-absorbent sheet using a highly water-absorbent resin and an ethylene gas adsorbent. Methods for storing are known.

Other water-absorbent sheet products used for various applications include, for example, those having a structure in which a highly water-absorbent resin powder is sandwiched between two water-permeable sheet substrates, and a highly water-absorbent resin on a sheet substrate surface. In addition to providing a pattern-shaped water-absorbing layer with a coating agent containing, and forming an adhesive layer on the non-patterned portion and pasting another sheet substrate, various forms are known. .

[Problems to be solved by the invention]

However, in the case of the above-mentioned conventional technology, for example, when packaging fruits and vegetables, it is necessary to separately store two types of materials, a water-absorbing sheet and an ethylene gas adsorbent, in a packaging form, and a large amount of fresh food In the case of packaging processing, there are various problems such as extra time and labor, a reduction in overall work efficiency, and an increase in cost.

Furthermore, during transportation, the sachet containing the ethylene gas adsorbent is damaged, and the ethylene gas adsorbent inside adheres to the surface of the fruits and vegetables, thereby deteriorating the appearance of the product. There was a risk of contamination.

And, the packaging body for ordinary fresh food uses ordinary packaging materials, and the packaging materials themselves include:
For example, since there is no specific function such as antibacterial properties, it is impossible to reliably prevent freshness deterioration of fresh food due to contamination by food deteriorating bacteria with the water-absorbing sheet alone. Establishment was desired.

In addition, animal foods such as meat and fish and shellfish are generally stored and distributed in refrigerated conditions.At this time, a unique smell other than drip is generated from the tissue of the food, and this smell significantly lowers commercial value. Was causing it. In particular, once frozen and thawed, since the tissue itself is destroyed, the generation of odor is remarkable, and it has been strongly desired to establish an effective measure for preventing or removing this odor.

Products other than the above-mentioned fresh foods, for example, sanitary products, diapers, disposable rags, and products requiring high water absorption such as paper towels are also still effective in preventing bacterial contamination in addition to water absorption and deodorizing. The measures were not sufficient, and the development of a new product having a specific function capable of solving them in addition to water absorption was desired.

Furthermore, the conventional water-absorbing sheet has a problem that the absorbed water permeates to the back surface of the water-absorbing sheet, making it difficult to handle.

Under these circumstances, the present inventors have conducted intensive studies to solve the above-mentioned problems of the conventional technology, and as a result, combined a superabsorbent material and a specific functional material with a specific packaging form. The present inventors have found that the above problems can be solved by forming a water-absorbing sheet having a specific function together with water absorption, and have completed the present invention.

That is, an object of the present invention is to provide a novel water-absorbent sheet having high water absorbency and a specific function, and having a useful function as a material for maintaining accuracy of fresh food.

[Means for solving the problem]

The configuration of the present invention adopted to achieve such an object is to sandwich a mixture of a superabsorbent polymer material and a specific functional material between specific packaging materials and further integrate the mixture into a specific packaging material. It is characterized by being packed in a form, and specifically, is as follows.

(1) A mixture 3 containing a highly water-absorbing material and another specific functional material is integrally sandwiched by heat between a first inner layer 1 and a second inner layer 2 at least one of which is water-permeable. And at least one of the first outer layer 4 and the second outer layer 5 is made water-permeable, and then folded into the second outer layer 5 which is wider than the sandwich, and then folded.
The first outer layer 4 is applied from the outside of the outer layer 5, and the side part and the end part are heat-sealed, and the whole is packaged with the first outer layer 4 and the second outer layer 5. Water absorption sheet.

(2) The water-absorbent sheet having the functionality described in (1) above, wherein the specific functional material is a material having at least one specific function such as antibacterial property, deodorizing property, or ethylene gas adsorbing property.

(3) The water-absorbent sheet having the functionality described in (1) above, wherein the mixture is sandwiched and integrated between the first inner layer 1 and the second inner layer 2 together with a binder made of a thermoplastic resin.

(4) The water-absorbing sheet having the functionality described in (1) above, wherein the whole is sandwiched and integrated by a heated embossing roll.

 Subsequently, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which a mixture 3 containing a superabsorbent material and a specific functional material is sandwiched and integrated between an inner layer 1 and an inner layer 2 and then mixed. The outer layer 5 wider than the sandwiched body is folded into the side portion, and then the outer layer 4 is applied from above, the side portion and the end portion are heat-sealed, and the whole is packaged by a package composed of the outer layer 4 and the outer layer 5. It is sectional drawing of the water absorption sheet | seat which has the functionality obtained by doing.

Examples of the packaging material constituting the inner layer and the outer layer include, for example, non-size paper, nonwoven fabric, hydrophilic polyethylene,
Water-permeable porous sheets such as polypropylene, cellophane,
Vinylon film, thermoplastic film foamed to have fine communication holes during film production, inorganic or high melting point nucleating agent added and stretched to form fine communication holes, other polyethylene or polypropylene Mixed paper with pulp, laminated body of paper and non-woven fabric, sized paper or non-woven fabric with cellulose membrane formed by viscose, cellulose membrane with fine pores formed, etc. In addition to the material used, it is also possible to use an appropriate type of non-water-permeable material such as a plastic film made of a thermoplastic resin, PE paper, or metal foil.

In particular, as the nonwoven fabric, a part or all of the nonwoven fabric of a thermoplastic resin, for example, a nonwoven fabric in which a resin such as polyolefin, polyester, or polyamide is impregnated or mixed with a fiber such as rayon or pulp, or a polyolefin, polyester, polyamide, or the like It is preferable to use a nonwoven fabric or the like made of fibers having a basis weight of 15 to 100 g / m ^2.
Are preferred.

In addition, as the paper, a paper on which soft paper such as a tissue paper having a basis weight of 15 to 60 g / m ² is laminated is used, but the paper is not particularly limited.

Among the materials such as the superabsorbent material and the specific functional material constituting the mixture (3), as the functional material, an appropriate function such as an antibacterial agent, a deodorant, an ethylene gas absorbent, or a combination thereof is appropriately used. A substance or a composition having a multifunctionality is used.

Antibacterial agents include antibacterial metal materials such as silver, copper, zinc, tin, lead, bismuth, cadmium, chromium, and mercury, zeolite, activated carbon, silica, activated clay, acid clay, alumina, activated bauxite, and bone charcoal. And those supported on a carrier such as molecular sieve, but the antibacterial material, the type of the carrier and the amount used thereof are not particularly limited.

 The following are illustrated as a deodorant.

(1) Physical adsorption deodorant Neutral activated carbon, fibrous carbon adsorbent, zeolite, activated alumina, acid clay, etc.

(2) Chemical deodorants Acidic, alkaline, oxidizing, and reducing agents.

(3) Physical / chemical deodorants Alkaline or acidic impregnated activated carbon, zeolites adsorbing vegetable essential oils, etc.

(4) Others Iron phthalocyanine derivatives, salts having a desulfurizing action such as zinc oxide, and mixtures of iron (II) compounds with L-ascorbic acid and alum.

Any deodorant other than these deodorants may be used, and a mixture of one or more of these deodorants can be used. These deodorants are 1m in sheet
It is preferable to mix with the superabsorbent material and sandwich between the packaging materials so that the sandwich is held in the range of 0.1 to 150 g per ² pieces.

As the ethylene gas adsorbent, a carbonaceous molecular sieve adsorbing bromine, preferably having a micropore of 4 to 6 °, or an acid water in which sodium bromate or potassium bromate is dissolved was added to activated carbon and reacted. Thereafter, a dried and pulverized one having a particle size of 5 to 500 μm is exemplified. Such an ethylene gas adsorbent is desirable because it is not affected by moisture, that is, does not release adsorbed ethylene gas in the presence of moisture. In general, activated carbon, zeolite, Oyaishi, and the like used as an ethylene gas adsorbent are not preferable because moisture adsorbs ethylene gas when released.

In addition to these functional materials, it is possible to use a material having an appropriate function, and the type is not particularly limited.

Next, examples of the superabsorbent material include starch / acrylate graft polymer, carboxymethylcellulose crosslinked product, vinyl alcohol / acrylate copolymer, polyacrylonitrile hydrolyzate, crosslinked polyacrylate, modified polyvinyl alcohol Examples thereof include acrylic acid polymers, acrylate / acrylamide copolymers, isobutylene / maleic anhydride copolymers, and any other material having high water absorption can be used as appropriate. It is also possible to use two or more of these superabsorbent polymer materials in combination.
The amount of superabsorbent polymer material, the sheet 1 m ² per 0.1
The range is preferably 200 g, particularly preferably 1 to 50 g.

In order to sandwich and integrate the super absorbent material and the specific functional material between the packaging materials, polyolefin, polyamide,
Thermoplastic resins such as polyester and other appropriate binders can be used.

In order to produce the water-absorbing sheet having the functionality of the present invention using the above-mentioned materials, for example, the following method can be employed.

That is, a mixture 3 of a highly water-absorbing material, a specific functional material and a binder is evenly sprayed on the inner layer material 2 in FIG. After that, the integrated base paper is cut into a fixed size, folded by an outer layer 5 wider than the holding body, and the outer layer 4 is applied from above, and the side portion is heat-sealed by a gear roll. Heat seal with a seal bar,
It can be manufactured by sandwiching and integrating the whole through a heated embossing roll.

In addition, the material of the inner layer and the outer layer is not limited to a single layer, and an appropriate laminate composed of multiple layers can be used.

(1) Between the heating embossing roll and the heating embossing roll (2) Between the heating embossing roll and the heating roll (3) Between the heating embossing roll and the roll (4) The heating roll Heating rolls (5) A method of passing through and integrating one of the rolls between the heating rolls.

The water-absorbing sheet having the functionality of the present invention is generally used as it is as a material for maintaining freshness of fresh food, for example, as it is inserted between fresh foods in boxing, bagging, tray packaging, and the like of the fresh foods. As a matter of course, it is also possible to use a food that is easy to dry, in which the freshness-keeping material is made to absorb water in advance to make it wet.

In addition, it can be used in an appropriate form as a material for sanitary products, diapers, disposable rags, paper towels and the like.

〔The invention's effect〕

As described above, the use of the functional water-absorbent sheet of the present invention has an advantage that freshness of fresh food can be maintained easily and at low cost without labor.
In addition, because the specific functional material is integrated with the superabsorbent polymer material, there is no danger of functional materials such as ethylene gas adsorbent and antibacterial agent contaminating fresh food due to breakage of the bag. It has unique effects such as:

In addition, there is an advantage that a water-absorbing sheet having an arbitrary function according to the purpose of use can be produced only by appropriately selecting and mixing a specific functional material together with the highly water-absorbing material.

Further, in the water-absorbent sheet of the present invention, when a highly water-absorbing material or the like is sandwiched and integrated between a water-permeable packaging material and a non-water-permeable, ie, waterproof, packaging material, water absorption may occur in actual use. It is possible to completely prevent the permeated water from permeating to the back surface of the water-absorbent sheet, solve the problems of the conventional water-absorbent sheet by simple means, and further increase the added value of the water-absorbent sheet. The industrial utility value is extremely high.

Hereinafter, the present invention will be described more specifically with reference to Examples of the present invention.

〔Example〕

Example 1 A mixture of activated carbon (Shirasagi A, manufactured by Takeda Pharmaceutical Co., Ltd.), an organic acid, and zinc oxide (manufactured by Dainichi Seika Kogyo Co., Ltd.) as a deodorant on paper having a basis weight of 25 g / m ² (MSP25, manufactured by Meitel) Daimushu 1300) respectively 10 g / m ^2, uniformly spread superabsorbent polymer material (steel chemical Co. AQUA kEEP 10SHP) a 20 g / m ^2, binder (manufactured by Toray Industries, Inc. Kemitto R272S) in an amount of 1 g / m ² and, the mixture layer resin coated paper (35 g / m ² paper polyethylene those extrusion coating at a thickness of 30μ on) sandwiched between, further having a basis weight of 25 g / m ² paper on top of the resin coated paper sheet feeding Then, the mixture was passed through a heating embossing roll and sandwiched and integrated.

The base paper was cut into a size of 320 × 210 mm, placed on a non-woven fabric (NA240JP2096, manufactured by Kuraray Co., Ltd.), and the lower non-woven fabric was folded into the base paper side. Further, the nonwoven fabric was fed from the upper part, and the side part was heat-sealed with a gear roll. The end portion was heat-sealed with a seal bar, and the whole was passed through a heated embossing roll to be sandwiched and integrated. After integration
A water-absorbent sheet was produced by cutting the mixture layer at the end portion to 330 × 210 mm and sandwiching the above mixture layer between the upper three layers and the lower two layers of the laminated material.

Example 2 Ethylene gas adsorption / removal agent (Mol Sivon NG manufactured by Takeda Pharmaceutical Co., Ltd.) on paper having a basis weight of 25 g / m ² (MSP25 manufactured by Meitel)
P6 / 8) 10 g / m ^{2 of} crushed product, binder (Chemit manufactured by Toray Industries, Inc.)
R272S) in a uniform amount of 0.5 g / m ² and further coated with polyethylene (Meter MSP25, M-16P manufactured by Mitsui Nippon Polymer Co., Ltd., extrusion-coated with a thickness of 30μ) to polyethylene. The coated embossing roll was placed inside with the coated embossing roll passed through the embossing roll (heating embossing roll temperature: 160 ° C.).

20g / m ^{2 of} superabsorbent polymer material (Aquakeep 10SHP, manufactured by Iron and Steel Chemical Co., Ltd.) on a paper coated with polyethylene on the above sandwiched and integrated paper, binder (manufactured by Toray Industries, Inc.)
(Chemit R272S) was evenly sprayed at an amount of 1.0 g / m ² , further covered with paper, and passed through a heated embossing roll to be integrally sandwiched (heating embossing roll temperature: 160 ° C.).

This was cut to 320 × 210 mm, placed on a non-woven fabric (NA240JP2096, manufactured by Kuraray Co., Ltd.), and the lower non-woven fabric was folded into the base paper side. Further, the nonwoven fabric was fed from the upper part, and the side part was heat-sealed with a gear roll. The end portion was heat-sealed with a seal bar, and the whole was sandwiched and integrated, and cut at the end portion.

[Brief description of the drawings]

 FIG. 1 shows a sectional view of a water-absorbent sheet of the present invention. DESCRIPTION OF SYMBOLS 1 ... Inner layer 2 ... Inner layer 3 ... A mixture of a superabsorbent polymer material and a functional material 4 ... Outer layer 5 ... Outer layer

────────────────────────────────────────────────── (5) Continuation of the front page (51) Int.Cl. ⁶ Identification code FI A41B 13/02 D (56) References JP-A-59-26502 (JP, A) Real opening sho-59-30876 (JP, U) Japanese Utility Model 1-85271 (JP, U) Japanese Utility Model 63-72525 (JP, U) Japanese Utility Model 64-22430 (JP, U) Japanese Utility Model Utility Model 61-175189 (JP, U) (58) (Int.Cl. ⁶ , DB name) B32B 1/00-35/00 B65D 81/26 A23L 3/00 A61F 13/18

Claims (4)

(57) [Claims] 1. A first inner layer (1) and a second inner layer (2) at least one of which is water-permeable, comprising a mixture (3) containing a superabsorbent material and another specific functional material. Between the first outer layer (4) and the second outer layer (5) to be water-permeable, and then the second outer layer (4) and the second outer layer (5) are wider than the sandwich body. After folding into the outer layer (5), the first outer layer (4) is applied from the outside of the folded second outer layer (5), the side portion and the end portion are heat-sealed, and the whole is covered with the first outer layer (5). 4) A functional water-absorbent sheet, characterized by being packaged by a second outer layer (5). 2. The functional water-absorbing material according to claim 1, wherein the specific functional material is a material having one or more specific functions such as antibacterial property, deodorizing property, and ethylene gas adsorbing property. Sheet. 3. The method according to claim 1, wherein the mixture is sandwiched and integrated between the first inner layer (1) and the second inner layer (2) together with a binder made of a thermoplastic resin. A water-absorbent sheet having the functionality described. 4. The functional water-absorbing sheet according to claim 1, wherein the whole is sandwiched and integrated by a heated embossing roll.