JPWO2018025676A1 - Nonwoven sheet - Google Patents

Abstract

An object of the present invention is to provide a non-woven sheet excellent in cleaning performance. A nonwoven fabric sheet comprising a web layer formed by an air laid method, wherein the nonwoven fabric sheet comprises a powder exhibiting acidity when in contact with moisture, and provides a nonwoven fabric sheet mainly composed of a water absorbing material.

Description

  The present invention relates to a nonwoven sheet, and more particularly to a nonwoven sheet containing a material that exhibits acidity when in contact with water. The nonwoven fabric sheet of the present invention is suitable for cleaning applications, in particular, wiping applications such as wiping for cleaning, wiping for skin cleaning, wiping for household wipers and industrial wipers, and application to cleaning objects And can be suitably used in the field of cleaning products, sundries and the like.

  Sheets containing materials that exhibit acidity upon wetting with water are known in the art. For example, Patent Document 1 includes, as an inner layer, a web layer formed by an air laid method in which an organic acid powder, a thermoadhesive fiber, and optionally a cellulose-based pulp are blended, and exhibits acidity when it is wetted with water. Disclosed is a cleaning sheet.

Patent No. 5413884

  The cleaning sheet of Patent Document 1 has a certain degree of rigidity as a whole in order to use heat fusible fibers as an essential component, and the cleaning sheet is cleaned when applied to a cleaning object having a curved surface portion and a corner portion. It is considered that it may be difficult to arrange in close contact with the entire surface of the target surface.

  In the case of a sheet containing a material exhibiting acidity by wetting with water, when the sheet does not exhibit a desired pH due to a chemical reaction of the material exhibiting acidity, outflow from the sheet, etc. when time passes after wetting with water. Will come. As a result, when the user continues using the sheet, the desired wiping and cleaning effect can not be obtained.

  An object of the present invention is to provide a non-woven sheet excellent in cleaning performance. A further object of the present invention is to provide a non-woven sheet capable of easily recognizing a suitable time for use.

The present invention for solving the above-mentioned subject has the following modes.
1. A nonwoven fabric sheet comprising a web layer formed by an air laid method, wherein the nonwoven fabric sheet contains a powder that exhibits acidity when in contact with moisture, and the web layer is mainly composed of a water absorbing material.
2. The powder is contained in the web layer, Nonwoven sheet as described in.
3. The powder is localized on one side of the web layer in the thickness direction of the web layer. Nonwoven sheet as described in.
4. The powder is uniformly distributed in the thickness direction of the web layer. Nonwoven sheet as described in.
5. The powder is layered on the web layer, Nonwoven sheet as described in.
6. The web layer is mainly composed of a water absorbing fiber. To 5. The non-woven sheet according to any of the above.
7. The non-woven fabric sheet comprises a particulate heat fusible resin having a particle size of 1 μm to 1000 μm. To 6. The non-woven sheet according to any of the above.
8. The web layer contains a fibrous heat-fusible resin having a fineness of 1 dtex or more and 120 dtex or less and an average fiber length of 1 mm or more and 100 mm or less. To 7. The non-woven sheet according to any of the above.
9. The non-woven sheet comprises a water-permeable or water-absorbent sheet adjacent to the web layer; To 8. The non-woven sheet according to any of the above.
10. The non-woven fabric sheet includes a water-permeable or water-absorbent sheet adjacent to the powder, which is disposed in a layer shape in contact with the web layer. Nonwoven sheet as described in.
11. The film layer which consists of a film was provided in one side of the said nonwoven fabric sheet. To 9. The non-woven sheet according to any of the above.
12. The non-woven sheet further includes an alkaline layer containing a powder that exhibits alkalinity when in contact with moisture. To 11. The non-woven sheet according to any of the above.
13. The non-woven sheet according to any of the preceding claims, wherein the web layer comprises the water-absorbing material in an amount of more than 60% by weight based on the weight of the web layer.
14. The non-woven sheet contains a pH indicator and a carrier in the same layer as the powder,
The pH indicator is fixed to the carrier by a quaternary ammonium salt; To 13. The non-woven sheet according to any of the above.
15. 14. A binder is further included, and the pH indicator is immobilized on the carrier by the quaternary ammonium salt and the binder. Nonwoven sheet as described in.
16. 14. The same layer contains fibers, and the carrier having the pH indicator fixed thereto and the powder are held in the voids formed by the fibers. Or 15. Nonwoven sheet as described in.
17. The same layer includes a heat-fusion resin, and a part of the carrier to which the pH indicator is fixed is fixed in a state of being covered with the heat-fusion resin. . To 16. The non-woven sheet according to any of the above.
18. The adjacent layer adjacent to the same layer contains a heat fusible resin, and is fixed in a state in which a part of the carrier on which the pH indicator is fixed present in the same layer is covered with the heat fusible resin. 14. characterized in that To 17. The non-woven sheet according to any of the above.
19. 14. The quaternary ammonium salt is at least one selected from the group consisting of benzirconium chloride, cetyl pyridinium chloride, benzethonium chloride, and didecyldimethyl ammonium salt; To 18. The non-woven sheet according to any of the above.
20. 14. The carrier fixing the pH indicator is cellulose and / or a cellulose derivative, 14. To 19. The non-woven sheet according to any of the above.
21. 15. The binder is characterized by being a water-insoluble polymer compound. The nonwoven fabric sheet in any one of to 20.
22. 14. To 21. It is a manufacturing method of the nonwoven fabric sheet in any one of,
Dissolving the pH indicator and the quaternary ammonium salt in a non-aqueous organic solvent;
Applying the solution obtained by the above step to the carrier;
A method of producing a non-woven sheet, comprising:
23. Further including the step of forming the carrier into a sheet,
22. The applying step is performed before the sheet forming step. The manufacturing method described in.
24. Further including the step of forming the carrier into a sheet,
22. The applying step is performed after the sheet forming step. The manufacturing method described in.

  The non-woven fabric sheet of the embodiment of the present invention containing a powder that exhibits acidity when in contact with moisture is a non-woven fabric sheet including a web layer formed by the air laid method, and the web layer is mainly composed of a water absorbing material. That is, the web layer comprises the water-absorbing material in an amount of more than 60% by weight based on the weight of the web layer. In the nonwoven fabric sheet of the present invention, since the web layer is mainly composed of a water absorbing material, a large amount of water can be held when water is contained, and it is easily deformed along the surface to be cleaned of the object to be cleaned Also, the adhesion to the surface to be cleaned is good. Thereby, the nonwoven fabric sheet of the present invention can effectively apply water containing an acidic component to the surface to be cleaned, and exhibits excellent cleaning performance. Such an effect tends to be higher as the water-absorbent material content in the web layer is higher.

  Moreover, the nonwoven fabric sheet containing the powder (Hereafter, it is also called "acidic powder") which exhibits acidity when contacting with water | moisture content of another aspect of this invention further contains the pH indicator of the form fixed to the support | carrier. When water is applied to the non-woven sheet, the acid powder comes in contact with the water to exhibit acidity. At this time, the pH indicator is colored (colored) or discolored according to the change of the hydrogen ion concentration, thereby changing the color of the non-woven sheet. The user can visually recognize that the non-woven fabric sheet exhibits the desired pH and then that the non-woven fabric sheet does not exhibit the desired pH by the color change of the non-woven fabric sheet. Therefore, the user can use the non-woven sheet while the non-woven sheet is exhibiting the desired pH (that is, the time suitable for use) and easily determine the end time of use of the non-woven sheet. be able to.

Fig.1 (a)-(k) is a figure which shows the structural example of the nonwoven fabric sheet which concerns on the 1st and 3rd aspect of this invention. Fig.1 (a) and (b) are figures which show the structural example of the nonwoven fabric sheet which concerns on the 2nd and 3rd aspect of this invention. Fig.1 (a)-(f) is a figure which shows the structural example of the nonwoven fabric sheet which concerns on the specific aspect of this invention. It is a schematic diagram which shows the web formation apparatus which can be used in the manufacturing method of the nonwoven fabric sheet of this invention.

<Non-woven sheet>
The non-woven fabric sheet according to the embodiment of the present invention is a non-woven fabric sheet including a web layer formed by an air laid method, and the non-woven fabric sheet contains a powder exhibiting acidity when contacted with moisture. And a water absorbent material. In the embodiment of the present invention, the web layer of the non-woven sheet is in an amount of more than 60% by mass, preferably 65% by mass or more, more preferably 70% by mass or more based on the mass of the entire web layer. , Including water absorbent material. When the water-absorbent material is contained in an amount of more than 60% by mass based on the weight of the entire web layer, the non-woven sheet can contain a large amount of water when it is contained, and the object to be cleaned can be cleaned It is easily deformed along the target surface and exhibits good adhesion to the cleaning target surface. The non-woven sheet may contain a heat fusible resin.

  The nonwoven fabric sheet according to the embodiment of the present invention further contains a pH indicator and a carrier in the same layer as the powder, and the pH indicator is fixed to the carrier by a quaternary ammonium salt. It is characterized by

  Hereinafter, the present embodiment will be described with reference to the drawings, but the present embodiment is not limited to the embodiments. In the drawings, the same reference numerals indicate the same components. Duplicate descriptions may be omitted for identical components.

[First aspect]
FIG. 1 is a view showing the configuration of the nonwoven fabric sheet according to the first and third aspects of the present embodiment for the purpose of illustration rather than limitation. With reference to FIG. 1, the structure and effect of the nonwoven fabric sheet which concerns on the 1st aspect of this Embodiment are demonstrated.

  The nonwoven fabric sheet 1000 which concerns on the 1st aspect of this Embodiment illustrated by Fig.1 (a) has a single layer structure which consists of the web layer 100. As shown in FIG. The web layer 100 is mainly composed of a water absorbing material 110 (not shown). A powder 120 (not shown) that exhibits acidity when contacted with moisture is incorporated into the web layer 100. The web layer 100 is formed, for example, of an air-laid sheet material of a web material including a water-absorbent material 110, a powder 120 which exhibits acidity when contacted with moisture, and a heat-fusible resin 130 (not shown). And thermally melting the heat fusible resin 130 to bond the components. In the manufacturing process of the nonwoven fabric sheet of the present embodiment, by using the dry laid method, the reaction between the water and the powder 120 exhibiting acidity when contacted with moisture is prevented.

  In the web layer 100, the powder 120 that exhibits acidity when in contact with moisture is fixed in a state where a part of the powder 120 is covered with the heat-fusible resin 130. Therefore, the powder 120 which exhibits acidity when in contact with moisture hardly falls off from the non-woven fabric sheet 1000, and the powder 120 can be in contact with moisture when the non-woven fabric sheet 1000 is used.

  In this example, both the water absorbing material 110 and the heat fusible resin 130 are blended in a fibrous form as constituent fibers for constituting the web layer 100. However, the present invention is not limited to this, and in the present embodiment, the heat fusible resin may be blended in a particulate form. Generally, when the heat fusible resin is compounded in particulate form, the non-woven sheet has higher flexibility than when it is compounded in fibrous form, and the shape of the object to be cleaned in cleaning applications It is easy to deform according to. On the other hand, when the heat fusible resin is blended in a fibrous form, rigidity is obtained in the non-woven fabric sheet, and the non-woven sheet tends to be excellent in scraping ability in cleaning applications. In addition, the less the blending amount of the heat fusible resin, the higher the flexibility of the non-woven fabric sheet and the lower its rigidity. Therefore, the form and blending amount of the heat-fusible resin in the non-woven fabric sheet can be appropriately set according to the target performance. The heat fusible resin in fibrous form and the heat fusible resin in particulate form may be used in combination.

  In the present embodiment, powder 120 which exhibits acidity when in contact with moisture is contained in nonwoven sheet 1000 itself. Therefore, the user of the non-woven fabric sheet 1000 can save the trouble of separately blending the cleaning agent by himself or applying it to the stain.

  In the present embodiment, the web layer 100 of the non-woven fabric sheet 1000 is mainly made of a water absorbing material. Therefore, when water is given to the nonwoven fabric sheet 1000, the nonwoven fabric sheet 1000 can prevent the outflow of water by absorbing and holding water, and the nonwoven fabric sheet 1000 is relatively soft. Therefore, even if the cleaning target surface of the cleaning target (for example, the surface with dirt) is a corner portion or a curved surface, the non-woven fabric sheet 1000 is stuck so as to be in close contact with the cleaning target surface of the cleaning target It is possible to wipe away dirt and dirt. Thus, the component exhibiting acidity can be effectively applied to the object to be cleaned, and dirt can be made to float and fall off easily.

  The nonwoven fabric sheet 1000 (generally referring to the nonwoven fabric sheets 1010 and 1020) illustrated in FIGS. 1 (b) and 1 (c) has a multilayer structure including the web layer 100, and the web layer 100 is a water absorbent material. The main component is 110. In this example, a water-permeable or water-absorbent sheet 300 which is a sheet having a water-permeable property (water permeability) and / or a water-absorbing property (water absorption) is provided to cover one side or both sides of the web layer 100. ing. When the non-woven sheet includes a plurality of water-permeable or water-absorbent sheets 300, they do not necessarily have to be the same material. The water-permeable or water-absorbent sheet is hereinafter also simply referred to as a water-absorbent sheet. In this example, the web layer 100 and the layer of the water absorbing sheet 300 are adjacent to each other, and the heat sealing resin and / or the layer are separately applied when the heat sealing resin is contained in each layer. The entire surface is bonded by heat fusion with a binder. In the present embodiment, bonding may be performed by means such as physical entanglement of constituent fibers of each layer. Moreover, the web layer 100 and the water absorbing sheet 300 may be partially joined instead of the entire surface.

  According to the structure of FIG.1 (b) and FIG.1 (c), the effect similar to the nonwoven fabric sheet of a structure shown to Fig.1 (a) is acquired.

  That is, in the present embodiment, the powder 120 that exhibits acidity when in contact with moisture is included in the nonwoven sheet itself. Therefore, the user of the non-woven fabric sheet can save the trouble of separately blending the cleaning agent by himself or applying it to the stain.

  Further, in the present embodiment, the web layer 100 of the non-woven fabric sheet is mainly made of a water absorbing material. Therefore, when water is applied to the non-woven fabric sheet, the non-woven fabric sheet can prevent the outflow of water by absorbing and holding the water. Also, non-woven sheets are relatively flexible. Therefore, even if the surface to be cleaned of the object to be cleaned (e.g., the soiled surface) is a corner portion or a curved surface, the non-woven fabric sheet can be stuck to the surface to be cleaned of the object to be cleaned can do. Thus, the component exhibiting acidity can be effectively applied to the object to be cleaned, and dirt can be made to float and fall off easily.

  In addition, in addition to the web layer 100, in the structure of FIG.1 (b) and FIG.1 (c), the water-permeable or water-absorbent sheet 300 is included. Therefore, the flexibility of the non-woven fabric sheet is influenced by the nature of the water-permeable or water-absorbent sheet 300 and the proportion of the water-permeable or water-absorbent sheet 300 in the non-woven fabric sheet. In the case where the water-permeable or water-absorbent sheet 300 itself has high flexibility, the non-woven sheet containing this tends to be highly suitable for application to be applied along the surface to be cleaned. In addition, when the water-permeable or water-absorbent sheet 300 itself is high in rigidity, the non-woven sheet containing the same tends to be highly suitable for use in removing dirt when it is cleaned. In addition, the influence of the properties of the water-permeable or water-absorbent sheet 300 becomes greater as the ratio of the water-permeable or water-absorbent sheet 300 in the nonwoven fabric sheet becomes higher.

  Moreover, according to the configuration of FIG. 1 (b) and FIG. 1 (c), in addition to the above effects, the possibility of powder fall off from the non-woven sheet of the powder 120 exhibiting acidity when contacted with moisture is further It can be reduced.

  The nonwoven fabric sheets 1030 and 1040 shown in FIG. 1 (d) and FIG. 1 (e) are relative to one water-permeable or water-absorbent sheet 300 in the configuration shown in FIG. 1 (b) and FIG. And a configuration in which the low breathable film 400 is substituted. Each web layer 100 of the nonwoven fabric sheets 1030 and 1040 is mainly composed of the water absorbing material 110. In the configuration having the low breathable film 400 on one side, in addition to the same effects as the configurations shown in FIG. 1 (b) and FIG. 1 (c), the surface on the film disposition side of water containing an acidic component generated during use. It is possible to prevent the outflow of water and evaporation of water. Moreover, by bonding the film, the strength of the non-woven fabric sheet is obtained and it becomes easy to handle.

  In the above, the nonwoven fabric sheet 1000 which concerns on the 1st aspect of this invention was demonstrated using Fig.1 (a)-(e). In the nonwoven fabric sheet 1000, the web layer 100 is mainly composed of the water absorbing material 110. In this configuration, the powder 120 which exhibits acidity when contacted with moisture is dispersed or uniformly distributed in the thickness direction of the layer in the layer of the web layer 100 due to the presence of the water absorbing material 110 or the web layer 100. It can be localized on one side of the Furthermore, the water absorbent material 110 can absorb and hold water. Therefore, when the non-woven fabric sheet 1000 is used, the acidic component generated by the reaction between the powder 120 and the moisture can be retained on the non-woven fabric sheet for a certain period of time, and good washability can be obtained.

  Also, in the web layer 100, particularly when the water absorbent material 110 is in the form of fibers, the powder 120 is likely to be maintained in the layer by the presence of the water absorbent material 110. In addition, the nonwoven fabric sheet 1000 can be easily maintained in shape by the web layer 100 containing the water absorbing material 110. Therefore, it is possible to improve the yield of the powder 120 at the time of production, storage and use of the non-woven fabric sheet 1000, and to prevent powder falling even when the non-woven fabric sheet 1000 is deformed, for example, folded. Can. Therefore, the loss of the powder 120 exhibiting acidity when it comes in contact with moisture is prevented, leading to cost reduction. In addition, cost can be reduced by selecting the water absorbing material itself.

  As mentioned above, the structure of the nonwoven fabric sheet which concerns on the 1st aspect of this invention was demonstrated using Fig.1 (a)-(e). However, these are only examples, and other configurations and combinations of the respective configurations are also included in the scope of the present invention.

  The modified example of the nonwoven fabric sheet 1000 which concerns on the 1st aspect of this invention from FIG.1 (f) to FIG.1 (k) is shown non-limitingly for the purpose of illustration. The nonwoven fabric sheet shown in FIG. 1 (f) to FIG. 1 (k) is in contact with the water in addition to the web layer 100 containing the powder 120 which exhibits acidity when it is mainly made of the water absorbing material 110 and contacts water. It further comprises an alkaline layer 200 comprising a powder exhibiting alkalinity.

  The non-woven fabric sheet of the present invention according to this configuration exhibits acidity when it comes in contact with the moisture contained in the web layer 100 by wetting the surface on the web layer 100 side of the non-woven fabric sheet with water during use. The powder 120 comes in contact with moisture and exhibits acidity. In addition, by wetting the surface on the side of the alkaline layer 200 of both surfaces of the non-woven fabric sheet with water during use, the powder exhibiting alkalinity when contacted with moisture, which is included in the alkaline layer 200, contacts with moisture and is alkaline Present.

  Generally, water stains, rust, soap scum, stains inside electric pots, urine stones, tobacco smell, tobacco stains, etc. are known as alkaline stains. In addition, oil stains, hand soaking, hot water smell, smell of garbage, and burnt fish grille are known as acid stains. It is also known that alkaline soils are acidic and neutralize, and acidic soils are alkaline and have high cleaning effect.

  By selectively using the surface of the non-woven fabric sheet on the web layer 100 side for alkaline soiling and the surface of the non-woven fabric sheet on the alkaline layer 200 side for acidic soiling, alkaline soiling and acidity can be obtained. Good washability is obtained for both stains.

  In such usage, it is preferable that the self-neutralization reaction in the nonwoven fabric sheet during use, that is, the reaction between the acidic component in the web layer 100 and the alkaline component in the alkaline layer 200 does not easily occur. Therefore, as shown in FIG. 1 (g), FIG. 1 (h), and FIG. 1 (j), the web layer 100 and the alkaline layer 200 may be separated. An arrangement comprising layers of is preferred. In addition, the self-neutralization reaction can be reduced by applying water so that a small amount of water is in contact with only one side of the non-woven fabric sheet at the time of use.

  Alternatively, as another use, there is a method of utilizing a self-neutralization reaction in the non-woven fabric sheet in use. Specifically, when carbonate and / or bicarbonate are used as a powder exhibiting alkalinity when in contact with moisture, both components of the web layer 100 and the alkaline layer 200 can be obtained by including water in the non-woven fabric sheet at the time of use. React to generate carbon dioxide gas, and when applied to the object to be cleaned, the effect of floating dirt is enhanced.

[Second aspect]
FIG. 2 is a view showing the configuration of the nonwoven fabric sheet 2000 according to the second and third aspects of the present embodiment for purposes of illustration and not limitation. With reference to FIG. 2, the structure and effect of the nonwoven fabric sheet which concerns on the 2nd aspect of this Embodiment are demonstrated.

  The nonwoven fabric sheet 2010, 2020 which concerns on the 2nd aspect of this Embodiment illustrated by FIG. 2 (a) and (b) was laminated | stacked in layers on the web layer 100 and one surface of the web layer 100. And a powder 120 that exhibits acidity when in contact with moisture. That is, in the nonwoven fabric sheet 1000 according to the first aspect, the powder 120 exhibiting acidity when contacted with moisture was included in the web layer 100, but the nonwoven fabric sheet 2000 according to the second aspect (nonwoven fabric sheet 2010 and In 2020), powder 120 that exhibits acidity when in contact with moisture is placed in contact with web layer 100. The web layer 100 is mainly composed of the water absorbent material 110, and contains the water absorbent material 110 in an amount of more than 60% by mass based on the mass of the entire web layer.

  The laminated configuration of the web layer 100 and the powder 120 is, for example, depositing a web material containing the water absorbing material 110 and the heat fusible resin 130 in the form of a sheet by an air laid method to form a web layer, A mixture of powder 120 that exhibits acidity when in contact with moisture and particulate heat-sealable resin is further deposited thereon to form a step of heat-melting the heat-sealable resin. be able to. In the non-woven fabric sheet of the present embodiment, by using a dry method in the manufacturing process, the reaction between the powder 120 that exhibits acidity when it comes in contact with moisture and water is prevented. Hereinafter, the layer of the powder 120 laminated on one surface of the web layer 100 and exhibiting acidity when in contact with moisture is also simply referred to as a particle layer.

  Also in the nonwoven fabric sheet 2000 of the second aspect, the same effect as the nonwoven fabric sheet 1000 of the first aspect can be obtained. That is, in the present embodiment, the powder 120 that exhibits acidity when in contact with moisture is contained in the nonwoven fabric sheet 2000 itself. Therefore, the user of the non-woven fabric sheet 2000 can save the trouble of separately blending the cleaning agent by himself or applying it to the stain. Further, in the present embodiment, the web layer 100 of the non-woven fabric sheet 2000 is mainly made of a water absorbing material. Therefore, when water is given to the nonwoven fabric sheet 2000, the nonwoven fabric sheet 2000 can prevent the outflow of water by absorbing and holding water, and the nonwoven fabric sheet 2000 is relatively soft. Therefore, even if the surface to be cleaned (for example, the surface to which the object to be cleaned is contaminated) is a corner portion or a curved surface, the non-woven fabric sheet 2000 adheres to the surface to be cleaned of the object to be cleaned Can be Thus, the component exhibiting acidity can be effectively applied to the object to be cleaned, and dirt can be made to float and fall off easily.

  Also in the non-woven fabric sheet 2000 of the second embodiment, in addition to the web layer 100 and the powder 120 laminated in a layer on one surface of the web layer 100, the powder 120 exhibits acidity when in contact with moisture. It can further be configured to further include an alkaline layer 200 containing a powder that exhibits alkalinity when in contact with the

  The nonwoven fabric sheet of the present embodiment according to the configuration of this modification has the surface of the nonwoven fabric sheet on the web layer 100 side with respect to alkaline stains and the surface of the nonwoven fabric sheet on the alkaline layer 200 side with respect to acidic stains. By selective use, good washability is obtained for both alkaline and acidic soils. In this method of use, it is preferable that no self-neutralization reaction in the nonwoven fabric sheet during use, ie, reaction between the acidic component and the alkaline component does not occur. For that purpose, the alkaline layer 200 is preferably provided on the side of the web layer 100 opposite to the surface on which the powder 120 that exhibits acidity when in contact with moisture is laminated.

  Alternatively, as another use, there is a method of utilizing a self-neutralization reaction in the non-woven fabric sheet in use. Specifically, when carbonate and / or bicarbonate are used as a powder exhibiting alkalinity when contacted with moisture, both acidic and alkaline components react by containing water in the non-woven sheet at the time of use. Carbon dioxide gas is generated, and when applied to a cleaning object, the effect of floating dirt is enhanced.

[Third aspect]
The configuration of the nonwoven fabric sheet (nonwoven fabric) of the third aspect of the present embodiment will be described with reference to FIGS. 1 and 2 again. In the drawings, the same reference numerals indicate the same components. Duplicate descriptions may be omitted for the same components.

  The nonwoven fabric sheet which concerns on a 3rd aspect has the structure which further contains a pH indicator and a carrier with respect to the structure of the 1st aspect demonstrated using FIG.1 and FIG.2, and a 2nd aspect. The pH indicator and the carrier are contained in the same layer as the layer (acidic powder-containing layer) containing powder (acidic powder) 120 that exhibits acidity when in contact with moisture.

  In the configuration examples shown in FIGS. 1 (a) to 1 (k), as described above, since the powder 120 that exhibits acidity when contacted with moisture is included in the web layer 100, the web layer 100 contains acid powder. It becomes a layer. Further, in the configuration example shown in FIG. 2A and FIG. 2B, since the powder 120 exhibiting acidity when contacted with moisture is included in the particle layer in contact with the web layer 100, these particles The layer becomes an acidic powder-containing layer. The acidic powder-containing layer contains powder 120 that exhibits acidity when in contact with moisture, a pH indicator, and a carrier. The pH indicator is formulated in a form fixed to a carrier.

  Hereinafter, in the present specification, when referring to the “nonwoven fabric sheet contains a pH indicator” configuration, “a pH indicator is contained in a form fixed to a carrier” unless otherwise specified. It is intended to be a configuration. When it is said that "a pH indicator is contained in a form fixed to a carrier", it is a matter of course that the whole amount of the pH indicator blended in the non-woven fabric sheet may be fixed to the carrier, It does not have to be fixed to the carrier. That is, the nonwoven fabric sheet may contain a pH indicator that is not fixed to the carrier. The powder and pH indicator that exhibit acidity when in contact with moisture can each be contained in one kind, and are not limited thereto, and plural kinds are contained in the same layer and / or different layers of the nonwoven sheet. It can be done.

  As shown in FIGS. 1 (f) to 1 (k), in the configuration in which the non-woven fabric sheet has an alkaline layer (hereinafter also referred to as "alkaline powder-containing layer") 200 containing a powder exhibiting alkalinity when contacted with moisture. The pH indicator can also be formulated into the alkaline powder-containing layer. Also in the alkaline powder-containing layer, it is desirable that the pH indicator be incorporated in a form fixed to a carrier.

  By including the pH indicator in the form of being fixed to the carrier, the pH indicator can be easily incorporated into the desired layer of the non-woven sheet, and the outflow of the pH indicator from the non-woven sheet during use can be prevented .

  In the nonwoven fabric sheet according to the present embodiment, the sheet is exhibited by the color change of the sheet brought about by the pH indicator contained in the acidic powder-containing layer (and the pH indicator contained in the alkaline powder-containing layer, if present). The status of the pH, in particular whether or not the desired pH is being presented, is visually recognized.

  By blending a pH indicator in the same layer as the acidic powder-containing layer (and the alkaline powder-containing layer, if present), the non-woven fabric sheet quickly changes color or changes color in response to the pH change upon contact with water. Can.

  In the non-woven fabric sheet according to the embodiment of the present invention, the acid powder-containing layer and / or the alkaline powder-containing layer (if present) is the outermost layer, or the outermost layer is acidic, for easy recognition of color change. Even if it is another layer other than a powder content layer, it has the composition which can visually recognize the color of an acid powder content layer from the exterior via other layers. For example, the other layers may be mesh structures or perforated structures, thin in thickness or translucent or transparent in material, and the lower layer may be seen through.

  The acidic powder-containing layer and / or the alkaline powder-containing layer may contain, in addition to the pH indicator and the acidic powder and / or alkaline powder, fibers, a heat-sealable resin, an effect promoter, and the like. The fiber, the heat fusible resin, and the effect promoter may each be of one type or a plurality of types.

  As an example of the configuration for preventing the pH indicator and the acidic powder and / or the alkaline powder from falling off from the non-woven sheet, the following specific embodiments will be described. Hereinafter, the acidic powder and / or the alkaline powder will be comprehensively described as a "functional material". In addition, the acidic powder-containing layer and / or the alkaline powder-containing layer will be comprehensively described as a "functional substance-containing layer".

(First Specific Embodiment)
FIG. 3A is an example in which the functional substance-containing layer contains the fiber F. In the functional substance-containing layer 160 containing the fiber F, the functional substance D is prevented from falling off by being held in the void formed by the fiber F, that is, the void in the fiber structure constituted by the fiber F. ing. The pH indicator I can be held on the non-woven sheet by fixing the fiber F as a carrier. Alternatively, the pH indicator I may be held in a void in the fiber structure constituted by the fiber F in the same manner as the functional substance D, using a material other than the fiber F as a carrier and being fixed thereto. Can. Alternatively, both may be used. Details of the carrier will be described later.

  The functional substance-containing layer 160 containing fibers can contain only the pH indicator I, the functional substance D, and the fibers F. In addition to the pH indicator I, the functional substance D, and the fiber F, the functional substance-containing layer 160 containing a fiber may contain a heat fusible resin, an effect accelerator, and the like. Also, the fiber F itself may be a heat fusible resin.

(Second specific embodiment)
FIG. 3 (b) is an example in which the functional substance-containing layer contains the heat fusible resin A. The functional substance-containing layer 140 containing the heat fusible resin is obtained by melting the heat fusible resin A in the mixture containing the pH indicator I, the functional substance D, and the heat fusible resin A. It is obtained. In this example, the pH indicator I and the functional substance D in the functional substance-containing layer are fixed (also referred to as binding or adhesion) in a state where a part of the pH indicator I and the functional substance D is covered with the heat fusible resin A.

  In the functional substance-containing layer 140 containing the heat fusible resin, the pH indicator I and the functional substance D are fixed in a partially coated state when the heat fusible resin A is solidified. By this, powdering is prevented. Also, the heat fusible resin A is compounded in an amount not to cover the whole of the pH indicator I and the functional substance D, and the pH indicator I and the functional substance D are coated with the heat fusible resin A It has parts that are not, and contact with water and elution when using the sheet is guaranteed.

  The functional substance-containing layer 140 containing the heat fusible resin can contain only the pH indicator I, the functional substance D, and the heat fusible resin A. In addition to the pH indicator I, the functional substance D, and the heat-fusible resin A, the functional substance-containing layer 140 containing the heat-fusible resin contains fibers, an effect accelerator, and the like. It is also good. Also, the heat fusible resin itself may be fibrous.

(Third Specific Embodiment)
FIG. 3C is an example in which the layer adjacent to the functional substance-containing layer contains the heat fusible resin B. The layer 200 containing the heat fusible resin B adjacent to the functional substance containing layer 150 has the heat fusible resin B disposed on the surface of the functional substance containing layer 150 and is thermally fused. It is obtained by melting. In this example, the pH indicator I and the functional substance D in the functional substance-containing layer 150 are fixed in a state where a part of the pH indicator I and the functional substance D is covered with the heat-fusible resin B. The heat fusible resin A contained in the layer 140 and the heat fusible resin B contained in the layer 200 may be the same resin or different resins.

  The functional substance D contained in the functional substance-containing layer 150 is partially covered when the heat fusible resin B melted in the layer 200 containing the heat fusible resin B adjacent thereto solidifies. By being fixed, powdering is prevented. Also, the functional substance D has a portion not covered with the heat-fusible resin B, and the contact with water and the elution at the time of using the sheet are guaranteed.

  The layer 200 containing the heat fusible resin B can contain only the heat fusible resin B. In addition to the heat-fusible resin B, the layer 200 containing the heat-fusible resin B may contain fibers, an effect accelerator, and the like. When these other components are contained, the layer 200 containing the heat fusible resin B is a mixture of the heat fusible resin B and these other components on the surface of the functional substance-containing layer 150 to obtain heat. It can be obtained by melting the heat fusible resin B by

  In detail, the nonwoven fabric sheet of the example shown in FIG. 3 (c) includes a layer 200 containing a heat-fusible resin B, a functional substance-containing layer 150 composed of a pH indicator I and a functional substance D, and a pH indicator I , Functional substance D, and functional substance-containing layer 140 containing heat fusible resin A, and has a three-layer structure. In the case of this example, the functional substance-containing layer 140 can also contribute to the prevention of dusting of the pH indicator I and the functional substance contained in the functional substance-containing layer 150 positioned as the intermediate layer.

  Here, a functional substance-containing layer 150 consisting of a pH indicator I and a functional substance D, and a functional substance-containing layer 140 further containing a heat fusible resin A in addition to the pH indicator I and the functional substance D Although illustrated and described as separate layers, the two layers are integrally configured, and the constituent materials, pH indicator I, functional substance, and heat fusible resin A, are unevenly distributed in the thickness direction. The structure which comprises the functional substance containing layer 140 of one layer is also contained in this aspect. According to this aspect, particularly when powdery material is unevenly distributed on one surface side of the functional substance-containing layer 140, powder removal is effective by arranging the layer 200 adjacent to the surface. Can be prevented.

  Also, although both the layer 150 and the layer 140 are illustrated and described as containing the pH indicator I and the functional substance D, the pH indicator I is contained in only one of the layer 150 and the layer 140. It may be done. From the viewpoint of the visibility of the color change of the non-woven fabric sheet, the pH indicator I is preferably contained on the outer surface side of the non-woven fabric sheet.

  In the present embodiment, the layer 200 containing the heat fusible resin B may be provided on both sides of the functional substance-containing layer. That is, for example, the configuration (not shown) including the layer 200 containing the heat fusible resin B, the functional substance containing layer, and the layer 200 containing the heat fusible resin B in this order is not It is a range.

  In the present embodiment, the non-woven fabric sheet is, for example, of the outer surface of the laminate of the functional substance-containing layer and the layer 200 containing the heat fusible resin B for the purpose of functionalization such as surface modification or strength (rigidity). The multi-layered structure (not shown) in which another layer 350 is laminated on one side or both sides of In that case, the other layer 350 adopts a configuration that does not hinder the visual recognition of the color change of the non-woven fabric sheet.

(Fourth aspect)
The nonwoven fabric sheet according to the embodiment of the present invention described above may be formed by heat seal processing. As one example, FIG. 3D shows a configuration in which another layer 350 containing a heat fusible resin is laminated on both sides of the functional substance-containing layer 150, and the four sides are heat-sealed. At least one of the other layers 350 has a configuration in which the color of the functional substance-containing layer 150 can be recognized through the other layer 350.

(Fifth aspect)
FIG. 3E shows an example in which an adhesive layer is provided adjacent to the functional substance-containing layer 150. The adhesive layer 500 adjacent to the functional substance-containing layer is obtained by disposing the adhesive layer on the surface of the functional substance-containing layer. The adhesive layer is not particularly limited as long as it is a layer exhibiting an adhesive function so that powdering of the pH indicator I and the functional substance D contained in the functional substance-containing layer 150 is prevented, for example, a hot melt adhesive Etc.

  Specifically, the non-woven fabric sheet of the example shown in FIG. 3 (e) has an adhesive layer 500 made of a hot melt adhesive such as a thermoplastic resin, for example, between the functional substance containing layer 150 and the other layer 350. Interveningly, it has a configuration in which interlayer bonding is performed by hot melt processing.

  More specifically, the non-woven fabric sheet of the example shown in FIG. 3 (e) has a function including the pH indicator I and the heat fusible resin A on the surface of the functional substance-containing layer 150 opposite to the adhesive layer 500. It has the organic substance containing layer 140. Also in the non-woven fabric sheet of the example shown in FIG. 3 (e), the functional substance-containing layer 140 containing the heat fusible resin A is positioned as an intermediate layer as in the case of the example shown in FIG. It can contribute to the prevention of dusting of the pH indicator I and the functional substance contained in the functional substance-containing layer 150. Also, although the functional substance-containing layer 150 and the functional substance-containing layer 140 including the pH indicator I and the heat fusible resin A are illustrated and described as separate layers here, these two layers are integrated. In this case, it is also configured that one functional substance-containing layer 140 is configured, in which the pH indicator I, the functional substance, and the heat fusible resin A, which are constituent materials, are unevenly distributed in the thickness direction. Included in the embodiment. According to this embodiment, particularly when powdery material is unevenly distributed on one surface side of the functional substance-containing layer 140, powder removal is effective by arranging the layer 500 adjacent to the surface. Can be prevented.

  Also, although pH indicator I and functional substance D have been illustrated and described as being contained in both the outermost layer 140 and the layer 150 which is the inner layer, pH indicator I May be included in only one of them. From the viewpoint of the visibility of the color change of the non-woven fabric sheet, the pH indicator I is preferably contained on the outer surface side of the non-woven fabric sheet.

(Sixth aspect)
The functional substance-containing sheet according to the embodiment of the present invention described above may be formed by embossing. As one example, FIG. 3F shows a configuration in which another layer 350 is laminated on both sides of the functional substance-containing layer 140 containing the heat-fusible resin A, and the layers are adhered by embossing. At least one of the other layers 350 has a configuration that allows the color of the functional substance-containing layer 140 to be recognized through the other layer 350.

  In the above, the structure of the nonwoven fabric sheet of this invention was demonstrated using Fig.3 (a)-(f). However, these are exemplifications, and other configurations, for example, combinations of the illustrated embodiments are also included in the scope of the present invention. For example, the layer shown as the functional substance-containing layer 150 in the figure may be the functional substance-containing layer 160 containing the fiber F or the functional substance-containing layer 140 containing the heat fusible resin A, or , And the layer containing both of the fiber F and the heat fusible resin A. Similarly, configurations in which layers are replaced between these layers are included in the scope of the present invention.

  Hereinafter, each component and component of the nonwoven fabric sheet of the present embodiment will be described in detail.

(Web layer)
The nonwoven fabric sheet of the present embodiment includes a web layer formed by an air laid method. In the present embodiment, the web layer 100 is mainly composed of the water absorbing material 110, and the amount is more than 60% by mass, preferably 65% by mass or more, more preferably 70% by mass based on the mass of the entire web layer. The water absorbent material 110 is included in an amount of% or more.

(Water-absorbent material)
The nonwoven fabric sheet of the present embodiment is mainly made of a water absorbing material. Examples of water-absorbent materials include natural fibers such as pulp, hemp, cotton, silk, wool and mineral fibers, regenerated fibers such as rayon, and fibrous water-absorbent materials such as synthetic fibers such as polylactic acid and nylon (water-absorbent fibers Can be used. The water absorbent fibers can be used, for example, in the form of fibrillated chopped fibers. The average fiber length of the water-absorbent fiber is preferably 1 to 100 mm, more preferably 1 to 60 mm, and still more preferably 2 to 30 mm. The fineness of the water-absorbent fiber is preferably 1 dtex to 120 dtex, and more preferably 1 dtex to 85 dtex. In addition, when the average fiber length and fineness of the water-absorbent fiber are in the above-mentioned range, the formation of the web layer is easy, and it is easy to obtain a uniform dispersed state. Two or more water absorbing materials may be used in combination. As the water absorbing material, particulate water absorbing material (water absorbing resin particles) such as water absorbing resin particles can also be used as an aid. Examples of the water-absorbent resin particles include carboxymethyl cellulose, polyvinyl alcohol and a polymer absorbent (SAP). The average particle diameter of the particulate water-absorbing material is preferably 1 to 1000 μm, and more preferably 10 to 800 μm. When the average particle diameter of the particulate water absorbing material is in the above range, it is easy to obtain a uniform dispersed state.

  The web layer of the nonwoven fabric sheet of the present embodiment is mainly made of a water absorbing material, and preferably, is mainly made of water absorbing fibers. Powders that exhibit acidity when contacted with moisture can be present dispersed or unevenly distributed in the web layer due to the presence of the water-absorbing material.

  In addition, the water-absorbent material of the present embodiment contacts with water and the component (acidic component) of the powder dissolved in water at the time of use of the non-woven fabric sheet to absorb and hold them while releasing it slowly be able to. Therefore, at the time of use of the non-woven fabric sheet, the acidic component generated by the reaction with water can be applied continuously over a long period of time to the surface to be cleaned of the object to be cleaned.

(Powder that exhibits acidity when in contact with moisture)
The nonwoven fabric sheet of the present embodiment contains a powder that exhibits acidity when in contact with moisture. As a powder that exhibits acidity when it comes in contact with moisture, any grade of acid that can be used in cosmetics can be used without particular limitation, and when used in applications that do not touch the human body or the like and do not affect the environment, No special grade is specified. For example, malonic acid, maleic acid, citric acid, malic acid, tartaric acid, succinic acid, fumaric acid, hyaluronic acid, sodium dihydrogen phosphate or derivatives thereof, substances which are hydrolyzed to produce an acid, and the like can be used. Two or more acids may be used in combination. The acid is a solid composition, for example in the form of particles. Hereinafter, in the present specification, a powder that exhibits acidity when in contact with moisture is also simply referred to as acid particles. The acid may also contain water as crystal water. When crystal water is included, the solubility in water is increased, and the reactivity is improved. However, from the viewpoint of storage stability, it is preferable that the acidic layer does not contain water that causes deterioration, such as hydrolysis or reaction with carbonate and / or bicarbonate being initiated.

As an acid used for this Embodiment, the particle | grains of 5 to 5000 micrometers of average particle diameters are preferable. When the average particle diameter is 5 to 5000 μm, the particles are less likely to fall off, and a proper feeling of use can be obtained due to the appropriate granular feeling. The smaller the average particle size, the faster the dissolution rate, and the reaction proceeds immediately after wetting with water. Therefore, in the configuration including the layer containing carbonate and / or bicarbonate among the aspects of the present embodiment, the initial generation amount of CO ₂ gas when water is included at the time of use is increased. In addition, it is possible to reduce graininess that can affect the feeling of use of the non-woven sheet. On the other hand, when the average particle size is increased, dissolution proceeds gradually when in contact with water. Therefore, in the configuration including the layer containing a carbonate and / or a bicarbonate among the aspects of the present embodiment, it is effective in extending the duration of carbon dioxide gas generation when water is included at the time of use. In addition, by increasing the average particle size, there is an effect of reducing particle detachment.

  In the nonwoven fabric sheet according to the first aspect of the present embodiment, powder 120 which exhibits acidity when contacted with moisture is blended in web layer 100. In the nonwoven fabric sheet concerning the 2nd mode of this embodiment, powder 120 which exhibits acidity when contacted with moisture is arranged in contact with web layer 100. In the present embodiment, a powder that exhibits acidity when in contact with moisture can be formulated into the web layer and placed in contact with the web layer. The layer of the powder 120 which is disposed in contact with the web layer 100 and exhibits acidity when in contact with moisture is hereinafter also referred to simply as a particle layer.

  In the non-woven fabric sheet according to the first embodiment, the web layer may further contain a heat fusible resin in addition to the water absorbing material and the particles of the powder 120 that exhibits acidity when in contact with moisture. In this case, the powder particles that exhibit acidity when in contact with moisture, and the water-absorbent material can be fixed in the web layer in a state where a portion thereof is covered with the heat-fusible resin. Such a web layer may be used, for example, when the surface of the carrier sheet of the web forming apparatus or the other layer (for example, a water-permeable or water-absorbent sheet) constituting the non-woven sheet comes in contact with the water-absorbent material and moisture. It can be formed by depositing a mixture containing powder particles exhibiting acidity and a heat fusible resin, and thermally melting the heat fusible resin to bond the components.

(Particle layer)
In the nonwoven fabric sheet according to the second embodiment of the present embodiment, the powder 120 which exhibits acidity when in contact with moisture can constitute a particle layer disposed in contact with the web layer 100. The particle layer may further contain a heat fusible resin, in addition to the particles of the powder 120 that exhibit acidity when in contact with moisture. In this case, the particles of the powder that exhibits acidity when in contact with moisture are fixed in the particle layer in a state where a part of the powder is covered with the heat fusible resin. Such a particle layer is formed, for example, by disposing a mixture containing powder particles that exhibit acidity when brought into contact with moisture and a heat fusible resin on the surface of other layers constituting the nonwoven fabric sheet, such as a web layer. It can be formed by thermally melting a heat fusible resin and bonding the components.

(Heat fusible resin)
The nonwoven fabric sheet of the present embodiment can contain a heat fusible resin. The heat fusible resin can be blended into the web layer and / or the particle layer, and at that time, it can function as a constituent material for bonding the components in the layer to provide strength to each layer. In addition, the heat fusible resin can play the role of a binder which is disposed between the layers constituting the non-woven fabric sheet to bond the layers.

  For example, the heat fusible resin is uniformly mixed with the powder (and the water absorbing material, if included) which exhibits acidity when in contact with moisture, and is deposited in layers as one of the layers constituting the non-woven sheet. The powder (and the water-absorbing material, if contained) is partially covered in the particle layer (or web layer) by being heated, melted and brought into contact with moisture in the particle layer (or web layer) It can be fixed. The heat fusible resin can be in the form of particles, fibers, or any other form. The heat fusible resin is desirably in the form of particles from the viewpoint of uniform mixing with the powder (and the water-absorbing material, if contained) that exhibits acidity when in contact with moisture in the layer forming step. Also, from the viewpoint of bonding between a plurality of particles (and / or fibers) of the powder (and the water absorbing material, if contained), the heat fusible resin exhibits acidity when it comes in contact with moisture. It is desirable that it is fibrous. The heat fusible resin can be, for example, in the form of a short-cut fiber. You may use together heat-fusible resin of various shapes.

  As the heat fusible resin, for example, low density polyethylene (PE) having a melting point of 95 ° C to 130 ° C, high density polyethylene having a melting point of 120 ° C to 140 ° C, homopolymer or block copolymer having a melting point of 160 ° C to 165 ° C Polypropylene, a polypropylene having a melting point of 135 ° C. to 150 ° C., a low melting point polyethylene terephthalate (PET) having a melting point of 110 to 190 ° C., a low melting point polyamide having a melting point of 100 to 130 ° C., a melting point of 110 ° C. The low melting point polylactic acid of -150 ° C, polybutylene succinate having a melting point of 115 ° C, and the like can be mentioned. A thermoplastic resin having a melting point of more than 110 ° C. is preferably used in the present embodiment. Two or more kinds of heat fusible resins may be used in combination.

  When the thermally fusible resin is fibrous, the fineness of the thermally fusible fiber is preferably 1 dtex to 120 dtex, and more preferably 1 dtex to 85 dtex. The average fiber length of the heat-fusible fiber is preferably 1 to 100 mm, more preferably 1 to 60 mm, and still more preferably 2 to 30 mm. When the fineness and the average fiber length of the heat-fusible fiber are in the above-mentioned range, the formation of the web layer is easy, and it is easy to obtain a uniform binding strength and a dispersed state.

  When the thermally fusible resin is in the form of particles, the average particle diameter of the thermally fusible particles is preferably 1 to 1000 μm, and more preferably 10 to 800 μm. The average particle size of the heat fusible resin can be appropriately selected within the range in which the powder exhibiting acidity when contacted with the water to be used is not completely covered.

(Composition of heat fusible resin)
The heat fusible resin described above may be a composite of two or more components. For example, core-sheath fibers in which resins having different melting points are compounded, side-by-side fibers using different resins in cross sections perpendicular to the longitudinal direction, core-shell particles having a core and a shell, and the like can be mentioned. Among these, core-sheath fibers are preferably used because different resins can be easily complexed.

  As the core-sheath fiber, a core-sheath fiber having a melting point of the sheath portion lower than that of the core portion is suitably used. For example, a PP / PE composite core-sheath fiber comprising a core part made of polypropylene fiber (melting point 160 ° C.) and a sheath part made of polyethylene (melting point 130 ° C.) formed on the outer periphery of the core part can be mentioned.

  Further, as other core-sheath fibers, for example, PET / low melting point PET composite core-sheath fibers, high density polyethylene / low density polyethylene composite core-sheath fibers, polyethylene / low melting point PET composite core-sheath fibers, polyamide / low melting polyamide composite Core-sheath fibers, polylactic acid / low-melting polylactic acid composite core-sheath fibers, polylactic acid / polybutylene succinate composite core-sheath fibers, etc. may be mentioned.

  The core-sheath fibers generally have a sheath portion melting point of more than 110 ° C., and such core-sheath fibers are preferably used in the present embodiment.

  When core-sheath fibers in which the melting point of the sheath portion is lower than the melting point of the core portion are used in the nonwoven fabric sheet of the present embodiment, heating to a temperature higher than the melting point of the sheath portion and lower than the melting point of the core portion The resin of the sheath portion melts, and the resin of the core portion maintains its shape. Thereby, the molten resin in the sheath portion retains carbonate and / or bicarbonate in the carbonate layer and / or retains the acid in the acidic layer, and the absorbent material and the fibers of the core portion The effect of binding the components of the structure constituted by Therefore, the non-woven fabric sheet of the present embodiment can provide sheet strength after securing a void in the sheet, and can provide a sheet that is soft and excellent in strength.

  The composite of two or more components as described above can provide heat fusion property by the presence of the heat fusion resin exposed to the outside, and can function as a binder. Therefore, these composites can be compounded as a heat fusible resin in the present embodiment.

(Alkaline layer)
As a modified example included in the scope of the present embodiment, a layer (alkaline layer) including a powder exhibiting alkalinity when in contact with moisture can be further provided. Alkali inorganic salts such as carbonates and / or bicarbonates can be used as powders which exhibit alkalinity when contacted with moisture. As the alkali inorganic salt, any grade that can be used as a cosmetic can be used without particular limitation, and no special grade is specified when using it for applications that do not touch the human body or the like and have no problems with the environment. For example, sodium carbonate, sodium hydrogencarbonate, sodium sesquicarbonate, potassium carbonate, potassium hydrogencarbonate, calcium carbonate, magnesium carbonate, magnesium bicarbonate, calcium bicarbonate or derivatives thereof can be used. Two or more kinds of carbonates and / or bicarbonates may be used in combination. In particular, one or both of sodium hydrogen carbonate and sodium carbonate can be preferably used. The alkali inorganic salt is a solid composition, for example, preferably in the form of particles. The alkali inorganic salt may be in the form of being supported on a support such as silica, for example. The alkali inorganic salt may contain water as crystal water. When crystal water is included, the solubility in water is increased, and the reactivity is improved. However, from the viewpoint of storage stability, it is preferable that the layer containing a powder exhibiting alkalinity when in contact with water does not contain water that causes deterioration such as hydrolysis or reaction with an acid being initiated. In addition to this, metal oxides such as calcium hydroxide and sodium hydroxide, metal hydroxides, phosphates and silicates can be used as powders exhibiting alkalinity when in contact with moisture. As a powder which exhibits alkalinity when in contact with water used in the present embodiment, particles having an average particle diameter of 5 to 5000 μm are preferable. When the average particle diameter is 5 to 5000 μm, the particles are less likely to fall off, and a proper feeling of use can be obtained due to the appropriate granular feeling.

  The alkaline layer may further contain a heat fusible resin in addition to the alkaline particles. In this case, the alkaline particles are fixed in the alkaline layer in a state in which a part of the alkaline particles is covered with the heat fusible resin. Such an alkaline layer arranges, for example, a mixture of alkaline particles and a thermally fusible resin on the surface of one of the other layers constituting the non-woven fabric sheet to melt the thermally fusible resin by heat. It can be formed by

  Moreover, the acidic layer may further contain a water absorbing material. The water absorbent material may also have a fibrous form. In this case, the acidic layer can be formed, for example, by an air laid method.

(Effect promoter)
In the nonwoven fabric sheet of the present embodiment, one or more effect enhancers can be blended depending on the application.

  As the effect promoter, for example: oily base, moisturizer, touch improver, surfactant, polymer, thickening / gelling agent, solvent, propellant, antioxidant, reducing agent, oxidizing agent, preservative , Antibacterial agents, chelating agents, pH adjusters, acids, alkalis, powders, inorganic salts, ultraviolet absorbers, skin lightening agents, vitamins and their derivatives, anti-inflammatory agents, anti-inflammatory agents, hair growth agents, blood circulation promoters, Stimulant, hormones, anti-wrinkle agent, anti-aging agent, tempering agent, cooling agent, warming agent, wound healing promoter, irritation reducing agent, analgesic agent, cell activator, plant / animal / microbe extract, antipruritic agent , Keratin exfoliating / dissolving agent, antiperspirant, cooling agent, astringent, enzyme, nucleic acid, fragrance, pigment, coloring agent, dye, pigment, metal-containing compound, unsaturated monomer, polyhydric alcohol, polymer additive Anti-inflammatory and analgesic, antifungal, antihistamine, hypnotic sedative, mental stabilizer, antihypertensive Antihypertensive diuretics, antibiotics, anesthetics, antibacterial substances, antiepileptics, coronary vasodilators, herbal medicines, adjuvants, wetting agents, thickeners, tackifiers, antipruritic agents, keratin softeners, oily Raw materials, UV blockers, preservatives, disinfectants, antioxidants, liquid matrices, fat-soluble substances, polymeric carboxylates, additives, metal soaps, etc. may be mentioned.

  Effect enhancers can be incorporated into the web layer. When the nonwoven sheet has a layer different from the web layer, it can also be added to one or both of the web layer and another layer.

(Water-permeable or water-absorbent sheet)
As the water-permeable or water-absorbent sheet 300 of the present embodiment, any sheet can be used from the sheet having the property of passing water (water-permeable) and the sheet having the property of absorbing water (water-absorbing). it can. As a sheet having the property of passing water (water permeability), it is only necessary to pass water, and there is no limitation. As a sheet having a property of absorbing water (water absorption), a sheet capable of taking in and holding water inside and releasing the water inside can be used. That is, it can be said that the sheet having the property of absorbing water (water absorption) applicable to the present embodiment is a kind of sheet having the property of passing water (water permeability). The water-permeable or water-absorbent sheet 300 has a water absorption rate of 60 seconds or less, preferably 30 seconds or less, which is measured according to the method of measuring the sedimentation rate defined in JIS L1907. Alternatively, it is more preferable that the water absorption (or water flow) speed by the dropping method defined in the JIS L 1907 standard be 60 seconds or less, and 30 seconds or less. The lower the water absorbency of the water-permeable or water-absorbent sheet 300, the faster the speed of passing water through it, and in the case of a non-woven sheet using this, the reaction between the powder 120 and water that exhibit acidity when contacted with water is rapid. It is possible to generate water containing an acidic component in a short time. Moreover, the water-permeable or water-absorbent sheet 300 can hold water containing an acidic component for a long time as the water absorbency (water holding power) is higher.

  The water-permeable or water-absorbent sheet 300 can be, for example, a sheet having a non-woven fabric, a cloth or another mesh structure, and can be, for example, a special non-woven fabric such as Warif (registered trademark). For example, as a water-permeable or water-absorbent sheet having high water retentivity, any sheet having a property capable of gradually releasing the water passing through the inside or the water absorbed inside can be used over time. In addition, depending on the type of water-permeable or water-absorbent sheet 300, the non-woven fabric sheet to which it is bonded has high wet strength, which is the wet strength, and the effect of improving the wiping performance can be obtained. As such a water-permeable or water-absorbent sheet 300, for example, a non-woven fabric such as rayon spunlace can be preferably used.

  By using a thick sheet or a sheet having a low density as a water-permeable or water-absorbent sheet to be used on the surface, it is possible to provide the nonwoven sheet with the wet strength and the scraping performance. On the other hand, the use of a thin sheet or a highly water-permeable, highly breathable sheet makes it difficult to prevent the infiltration of water from the surface of the non-woven sheet and the outflow of water containing the produced acidic component, and the acidic component is immediately released. It is easy to get the effect. The water-permeable or water-absorbent sheet is appropriately selected according to the application and purpose.

  Moreover, you may surface-treat an unevenness | corrugation etc. on the surface of the water-permeable or water-absorptive sheet used as the outer layer of a nonwoven fabric sheet for the purpose of design improvement and the wiping-off property improvement in the case of using as cleaning articles. A plurality of water-permeable or water-absorbent sheets may be stacked and used.

(the film)
The film 400 has flexibility such that it can be applied along the cleaning target surface (including corners and curved surface) of the cleaning target when using the nonwoven sheet, and other layers of the nonwoven sheet In particular, any film having relatively low air permeability as compared to the water-permeable or water-absorbent sheet 300 can be used.

The lower the air permeability of the film, the higher the effect of preventing the outflow of water containing the acidic component generated during use of the non-woven sheet from the film disposition side of the film and the evaporation prevention effect of water. Therefore, by applying the surface on the opposite side to the surface on the film disposition side to the surface to be cleaned, etc., it is possible to apply water containing an acidic component to an application site for a long time. For example, the air permeability measured by the “fabric testing method for woven and knitted fabrics” defined in Japanese Industrial Standard JIS L 1096: 2010 is preferably 200 cm ³ / cm ² / s or less, more preferably 150 cm ³ / cm ^2. A film of 2 / s or less can be used. The air permeability is a unit area when a predetermined pressure is applied, and an amount of air permeating the film per unit time, and the larger the value, the higher the air permeability. The use of a film having a relatively low air permeability as compared to the other layers of the non-woven fabric sheet, in particular, the water-permeable or water-absorbent sheet, can make the carbon dioxide gas permeable.

  Examples of the film include resin films such as polyester, polyvinyl alcohol, polyethylene, polypropylene, and composite films of polyethylene and polypropylene.

(Other layers)
In addition to the web layer 100 and the functional substance-containing layers 140, 150, 160, the non-woven fabric sheet of the present embodiment has another layer 350 for the purpose of functionalization such as surface modification or strength (rigidity) imparting. Can be included.

  The other layer 350 may be, for example, any sheet having a property of passing moisture (water permeability) and / or a property of absorbing moisture (water absorption) such as non-woven fabric, cloth, paper and the like. Also, any film can be used. These sheets and films may be the water-permeable or water-absorbent sheets 300 and films 400 described above.

  The other layer 350 may include a heat fusible resin. When the other layer 350 includes a heat-fusible resin, the heat-fusible resin contained in the other layer 350 may be the same as or different from the heat-fusible resins A and B described above. It may be one type or a combination of two or more types.

  The use of a film having relatively low water permeability on one side of the functional substance-containing sheet can prevent the functional components from being eluted from the side when the sheet is used. That is, elution of the component of the functional substance from the other side can be promoted. With a transparent or translucent film, the color change of the non-woven fabric sheet can be easily viewed from the outside.

  The surface of the other layer 350 to be the outer layer of the functional substance-containing sheet may be subjected to surface processing such as imparting of irregularities and processing such as formation of holes or slits. For example, in applications such as food tray mats, it is preferable to use a perforated film or a slit film having a large number of holes formed on one or both sides of a functional substance-containing sheet, such as a sanitary material surface material. It can be used. With such a configuration, the functional material can be easily eluted by the holes and slits when the sheet is used, and the drip from the food can be absorbed by the inner layer of the functional material-containing sheet .

(Heat seal processing)
Heat sealing is a method of applying heat by means of heating means such as a heat sealer to cause interlayer adhesion. In the embodiment of the present invention, for example, a functional substance-containing layer consisting of only a pH indicator and a functional substance is used as an intermediate layer, and a layer 200 containing a heat fusible resin as another layer 350 is disposed on both sides. Then, the functional sheet having a multilayer structure can be formed by heat sealing the four sides. At least one of the layers 200 disposed on both sides of the functional substance-containing layer has a configuration through which the user can visually recognize the color change of the functional substance-containing layer. For example, the layer 200 may be transparent or translucent, or may have a mesh structure having a mesh size such that the constituent material of the functional substance-containing layer does not leak to the outside.

(Adhesive layer)
The method for forming the adhesive layer is not particularly limited, but it is preferably an adhesive layer obtained by hot melt processing. Hot melt processing is a processing method in which a thermoplastic resin is melted and extruded to bond a sheet to a sheet. It can be used for interlayer adhesion when bonding a functional substance-containing layer to another layer.

  Examples of thermoplastic resins that can be used for hot melt processing include ethylene / vinyl acetate copolymer (EVA), and resins generally known as hot melt adhesives can be used.

(Embossed)
Embossing is a process in which pressure is applied by a die with a concavo-convex pattern and heat is applied. This method can also be used for interlayer adhesion of multilayer structures. In addition, this method can also be used to perform surface processing such as unevenness on a functional substance-containing sheet having a single layer or multilayer structure.

(PH indicator)
The pH indicator is also referred to as an acid-base indicator, and is not particularly limited as long as it is an indicator that reacts with hydrogen ions in the solution and changes color tone according to the hydrogen ion concentration.

  Examples of pH indicators applicable to the embodiments of the present invention include methyl bio red, thymol blue, congo red, methyl yellow, bromothymol blue (also called bromthymol blue), methyl red, methyl orange, litmus, bromo cresol Synthetic dyes such as purple (also called brom cresol purple), phenol red, phenolphthalein, cresolphthalein, thymolphthalein, alizarin yellow R, eriochrome black T and the like can be mentioned. In addition, natural pigments such as red cabbage pigment, persimmon pigment, purple potato pigment, red radish pigment, purple corn pigment, elderberry pigment, and grape / blueberry pigment can be used.

  These synthetic dyes and natural dyes are generally known and can be purchased from manufacturers. In the present specification, pH indicators are also simply referred to as dyes.

  Although only one type of pH indicator may be used, by using two or more types in combination, it is possible to provide a non-woven product corresponding to a wide range of pH change. For example, color tone can be changed in the range of pH 2 to 9 by combining methyl orange and bromothymol blue.

(Carrier)
The carrier is a substance that is the basis for securing the pH indicator to the nonwoven sheet. The carrier is also referred to as a carrier or a support. The carrier is also a component of the layer of the non-woven sheet to which the pH indicator is blended. For example, if the non-woven sheet is a structure composed of fibers, the pH indicator may be fixed to the non-woven sheet with such fibers as a carrier. Alternatively, the pH indicator may be fixed to the non-woven fabric sheet by holding the carrier in a void in the fiber structure constituted by such a fiber using a component other than such a fiber, for example, a particulate matter as a carrier. Alternatively, both may be used.

  Examples of carriers applicable to the embodiments of the present invention include pulp derived from wood, hemp, cotton, manila hemp, cellulose, hemicellulose, microcrystalline cellulose, cellulose-based substances such as ion exchange cellulose, nylon, polyester And fine fibers of clay mineral such as kaolin, synthetic silica, glass, aluminum silicate, zeolite and bentonite, starch, protein and the like. The shape of the carrier is not particularly limited, and may be particulate or fibrous.

Pulp is an aggregate of cellulose fibers removed by mechanical or chemical treatment from wood or other plants. Plants, in particular their cell walls, generally contain cellulose and hemicellulose as constituents as water-insoluble polysaccharides. Among these, cellulose is a polysaccharide (carbohydrate) represented by a molecular formula (C ₆ H ₁₀ O ₅ ) _n , and hemicellulose is a general term for non-cellulose polysaccharides. The pulp is based on cellulose and generally contains both cellulose and hemicellulose, but may contain only cellulose. Hereinafter, in the present specification, cellulose and hemicellulose may be generically referred to as cellulose. That is, in the present specification, for example, the cellulose fiber is mainly composed of cellulose and may consist of cellulose alone, or may contain cellulose and hemicellulose.

  The pulp may be wood pulp obtained from wood materials such as softwoods and hardwoods, and may be non-wood pulp made from non-wood materials such as cotton, hemp and other herbaceous materials. Wood pulp can be obtained, for example, by subjecting wood chips to treatment such as kraft digestion, but the manufacturing method is not limited thereto, and wood pulp manufactured by a known method is an embodiment of the present invention. Examples of carriers applicable to the form of

  The microcrystalline cellulose is obtained by hydrolyzing pulp to remove an amorphous region, and the main component is crystalline cellulose.

  An ion exchange cellulose is what gave the property as an ion exchanger by introduce | transducing the group which carries out positive or negative charge in cellulose. Examples of ion exchange cellulose include diethylaminoethyl cellulose, carboxymethyl cellulose (CMC), phosphocellulose and the like.

  The cellulose derivative is a polymer compound obtained by partially modifying cellulose. The above-mentioned ion exchange cellulose is also a kind of cellulose derivative. Examples of cellulose derivatives include cellulose acetate, carboxymethylcellulose (CMC), hydroxyethylcellulose (HEC), hydroxypropyl methylcellulose (HPMC) and the like.

  A cellulose fiber can be preferably used from the point which is excellent in the formation and the appearance when it mix | blends with a nonwoven fabric. The cellulose fiber may be in the form of long fibers, short fibers or may be processed into powder. In terms of fiber length, cellulose fibers of about 0.01 mm to 5 mm can be preferably used. For example, powdered cellulose from Rettenmeyer has products with an average fiber length of 18 μm to 2.2 mm, and cellulose fibers of suitable fiber length can be used.

  Powdered cellulose fiber can be used for pigment coating treatment without pretreatment, but sheet cellulose fiber is used as pretreatment for pigment coating treatment, cut into a size suitable for subsequent mechanical treatment, and then disentangled and used You may.

<Quaternary ammonium salt>
The quaternary ammonium salt is formulated to promote the color development of the pH indicator to clarify the color change and to enhance the adhesion of the pH indicator to the carrier.

  Quaternary ammonium salts are salts of quaternary ammonium cations with other anions. A quaternary ammonium cation is a positively charged polyatomic ion represented by the molecular formula NR 4 + (wherein R is an alkyl group or an aryl group), and is always charged in solution regardless of the pH of the solution. It is known as a material. It is believed that this quaternary ammonium cation causes the pH indicator to be attached to the carrier by chemical bonding such as surface activity or ionic bonding.

  Examples of quaternary ammonium salts applicable to the embodiments of the present invention include cetyl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, lauryl trimethyl ammonium chloride, benzyl trimethyl ammonium chloride, benzyl triethyl ammonium chloride, cetyl pyridinium chloride, Benzalkonium chloride, benzethonium chloride, dialkyldimethyl ammonium chloride, didecyl dimethyl ammonium chloride, distearyl dimethyl ammonium chloride and the like can be mentioned. Cetyl pyridinium chloride, benzethonium chloride or didecyldimethylammonium chloride can be preferably used. In particular, benZirconium chloride can be preferably used.

<Binder>
Binders are used to fix the pH indicator to the carrier. The binder is preferably one that does not adversely affect the color reaction of the pH indicator. The binder is preferably a water-insoluble polymer compound.

  Examples of binders applicable to the embodiment of the present invention include cellulose derivatives such as nitrocellulose, cellulose acetate and ethylcellulose, or polyester resin, alkyd resin, polyurethane resin, epoxy resin, acrylic resin, vinyl chloride resin, Synthetic resins such as vinyl chloride copolymer resin, polyvinyl butyral resin, polyvinyl acetate emulsion, acrylic acid ester copolymer emulsion, vinylidene chloride copolymer emulsion, epoxy resin emulsion, synthetic rubber latex and the like can be mentioned.

  When a binder is used to fix a pH indicator to a carrier, first, the pH indicator mixed solution (hereinafter also referred to as a dye solution) is prepared by dissolving the binder in a solvent in addition to the pH indicator and the quaternary ammonium salt. Prepare. The dye solution is then coated on the carrier by methods such as spray coating or dropping. This physically fixes the pH indicator and the quaternary ammonium salt to the carrier.

  Since it is mixed as a component of the dye solution, it is preferable that the binder has high solubility in a solvent and low viscosity. The viscosity of the binder is preferably 60 mPa · s or less in a solution prepared by adjusting the binder to ethanol / toluene (1/1) (w / w) so that the final concentration is 10% by mass, and further It is desirable that it is 30 mPa · s or less.

(Content ratio of each component)
The web layer of the nonwoven fabric sheet of the present embodiment is water-absorbable in an amount exceeding 60% by mass, preferably 65% by mass or more, more preferably 70% by mass or more, based on the mass of the entire web layer. Contains the material.

  The nonwoven fabric sheet of the present embodiment contains a powder that exhibits acidity when in contact with moisture. Powders that exhibit acidity when in contact with moisture can be formulated into and / or in contact with the web layer. The content ratio (X: Y) of the water-absorbent material (X) in the web layer to the powder (Y) exhibiting acidity when contacted with moisture in the nonwoven sheet is, for example, more than 60%: 40% on a mass basis Less than 90%: in the range of 10%.

  The web layer can further include a heat fusible resin (Z). In this case, the content ratio of the water absorbing material (X) in the web layer to the total (Y '+ Z) of the powder (Y') that exhibits acidity when in contact with moisture and the thermally fusible resin (Z) [X: (Y '+ Z)] (mass basis) is, for example, in the range of more than 60%: less than 40% to 90%: 10%.

  When the ratio is in the above-mentioned range, the non-woven fabric sheet has flexibility and, at the time of use, can retain moisture suitably, so that the produced acidic component can be properly applied to the surface to be cleaned. In addition, before use, it is possible to maintain a powder that exhibits acidity when it comes in contact with moisture in the thickness direction in the web layer, thereby suppressing powder removal.

  In addition, if there is a web layer and another layer different from the web layer, an appropriate amount of one or more effect enhancers is compounded in one or more of the other layers (for example, particle layer) be able to.

(Content ratio of ingredients)
The blending amount of the functional substance (powder which exhibits acidity when in contact with moisture and powder which exhibits alkalinity when contacted with moisture when contained) depends on the type of material, use and desired effect. Also different.

  For example, from the viewpoint of the desired functional effect, the compounding amount is preferably as large as possible. Also, from the viewpoint of the effect of preventing powder fall, the blending amount is preferably as small as possible. For example, the blending amount is preferably 0.01% by mass or more, more preferably 0.2% by mass or more, and further preferably 0.5% by mass or more, based on the total amount of the sheet. It is particularly preferable that the content is at least mass%, and it is preferably at least 1 mass%, more preferably at least 3 mass%, still more preferably at least 5 mass%, and still more preferably at least 8 mass%. It is particularly preferable that the content is 10% by mass or more. Also, for example, the blending amount is preferably 60% by mass or less, more preferably 50% by mass or less, and still more preferably 40% by mass or less based on the total amount of the sheet.

(Basis weight)
The basis weight of the non-woven fabric sheet can be appropriately set according to the application. For example, the basis weight of the non-woven fabric sheet is preferably 30 to 300 g / m ² . That is, when the non-woven fabric sheet has a single layer structure comprising a web layer, the basis weight of the web layer itself can be 30 to 300 g / m ² . In addition, when the non-woven fabric sheet includes the water-permeable or water-absorbent sheet 300 and / or the film 400, the total basis weight of the web layer constituting the non-woven fabric sheet and the water-permeable or water-absorbent sheet 300 and / or the film 400 is It can be 30 to 300 g / m ² . The ratio of the basis weight of the web layer and the water-permeable or water-absorbent sheet 300 and / or the film 400 in the non-woven fabric sheet can be appropriately set according to the application and the target quality.

<Method of manufacturing non-woven sheet>
As a method of manufacturing the non-woven fabric sheet according to the first aspect of the present embodiment illustrated in FIG. 1A, for example, there is a method using a web forming apparatus that adopts a generally known air laid method. For example, on a carrier sheet for transporting a web layer, a homogeneous mixture of a water absorbing material, a powder that exhibits acidity when contacted with moisture, and a heat fusible resin such as polyethylene (PE), for example. The layers can be laminated, a carrier sheet can be disposed thereon, and the heat fusible resin can be melted by heat treatment to bond the components. At this time, by using the water-permeable or water-absorbent sheet of this embodiment for one or both of the two carrier sheets, the layer configuration illustrated in FIG. 1 (b) or FIG. 1 (c) is obtained. It is also good. In addition, by using an arbitrary film having relatively low air permeability as compared to the other layers in one of the carrier sheets, the layer configuration exemplified in FIG. 1 (d) or FIG. 1 (e) is obtained. It is also good. The carrier sheet is not essential in the present embodiment, and may be peeled off from the formed laminate after the heat treatment. In the present embodiment, in order to prevent the reaction between the powder that exhibits acidity when it comes in contact with moisture and water, the lamination of these is performed by a dry method. For forming a web layer mainly composed of a water absorbing material, a web forming apparatus employing a generally known air laid method can be used.

  As a method for producing a non-woven fabric sheet according to the second aspect of the present embodiment illustrated in FIG. 2, for example, a web layer containing a water absorbing material is produced by a web forming apparatus employing a commonly known air laid method. On the other hand, there is a method using a manufacturing method in which other layers are laminated separately. As such a method, a uniform mixture of a powder that exhibits acidity when contacted with moisture and a fusible binder particle, such as polyethylene (PE), is disposed on the surface of the web layer containing the water absorbing material. The fusible binder may be thermally melted and bonded to form a particle layer. At this time, when the web layer containing the water absorbing material is produced by the web forming apparatus adopting the air laid method, the water permeable or water absorbent sheet of the present embodiment is used as a carrier sheet for transporting the web layer. A laminate may be formed to obtain a non-woven sheet having a layer configuration exemplified in FIG. 2 (a). Moreover, you may obtain the layer structure illustrated by FIG.2 (b) by using arbitrary films whose air permeability is relatively low compared with another layer for one of a carrier sheet. The carrier sheet is not essential in the present embodiment, and may be peeled off from the formed laminate after the heat treatment.

  The layers of the non-woven fabric sheet prepared separately may be bonded by embossing or heat sealing. Moreover, there is also a method of providing an adhesive layer on at least one of the bonding surfaces of each layer of the non-woven fabric sheet to bond the layers. In the present embodiment, in order to prevent the reaction between the powder that exhibits acidity when it comes in contact with moisture at the time of production and water, these layers are stacked by a dry method.

(Manufacturing method of nonwoven sheet adopting air laid method)
The example of the manufacturing method of the nonwoven fabric sheet of this embodiment which employ | adopts the air laid method is shown in more detail. The method comprises a fibrillation step, a mixing step, a web forming step and a binding step.

(Disintegration process)
The fibrillation step is a step of fibrillating the material in the form of shortcut fiber by an air flow to obtain a fibrillated shortcut fiber.

  In the defibration method by the air flow of the shortcut fiber, the air flow is formed by a blower or the like, the shortcut fiber is supplied to the air flow, and the air is defibrillated by the stirring effect of the air flow.

  As a fibrillation method, it is preferable to disintegrate by a swirling air flow. According to the fibrillation method using a swirling air flow, the shortcut fiber can be sufficiently fibrillated, and when forming the air laid web by the air laid method, the dispersibility of the fibrillated shortcut fiber can be further enhanced .

  As a disintegration method using a swirling air flow, for example, there is a method in which a short cut fiber is inserted into a blower and disintegrated by the blower. In addition, air may be sent along the circumferential direction into the cylindrical container by a blower to form a swirling flow, and a shortcut fiber may be supplied into the swirling flow and stirred to break up the fibers.

  The flow velocity of the air flow is appropriately selected according to the amount of the short-cut fiber, but is usually in the range of 10 to 150 m / sec.

(Mixing process)
The mixing step is a step of mixing the water-absorbent material in the form of a defibrated short-cut fiber with other web layer essential constituent material to obtain a web material. In the first aspect of the present embodiment, the other web layer essential components include powders that exhibit acidity when in contact with moisture. At this time, any other material can be mixed simultaneously. The shape of any other material may be fibrous or particulate. Examples of optional other materials include heat-sealable resins, water-absorbent resin particles, auxiliary agents added as necessary, such as effect accelerators, and the like. There is no particular limitation on the order of addition of these materials, and these materials can also be added by, for example, spraying or the like after the mixing step.

  At the time of mixing, in order to improve the dispersibility of the defibrated shortcut fiber, it is preferable to stir the defibrated shortcut fiber and the other material. However, in order to prevent breakage of the defibrated shortcut fiber, it is preferable to apply stirring using an air flow instead of stirring using mechanical shear force.

  The mixing step may be performed after the fibrillation step or simultaneously with the fibrillation step. When the mixing step is performed simultaneously with the fibrillation step, the air flow in the fibrillation step is used to mix the fibrillation shortcut fiber with any material. Further, arbitrary particles may be introduced into and mixed with the web forming line of the defibrated shortcut fiber in the particle dispersion step described later.

(Web formation process)
The web forming step is a step of obtaining an air-laid web from a web material by an air-laid method. Here, the air laid method is a method of forming a web by randomly depositing fibers in a three-dimensional manner using an air flow.

(Particle dispersion process)
The particle dispersion step is a step of blending the powder into the web material by a known method. Either the method of mixing powder with fibers to form a web or the method of spraying on the surface of a web or a carrier sheet may be used. Powders that exhibit acidity when contacted with moisture may be spread on the surface of the web or carrier sheet in this particle spreading step.

  In the web forming step in the present embodiment, for example, a web forming apparatus 1 shown in FIG. 4 is used. The web forming apparatus 1 includes a conveyor 10, an air permeable endless belt 20, a fiber mixture supply means 30, a first carrier sheet supply means 40, a second carrier sheet supply means 50, and a suction box 60.

  Here, the conveyor 10 is configured by a plurality of rollers 11. The air permeable endless belt 20 is attached to the conveyor 10 and is configured to rotate. The fiber mixture supply means 30 supplies the fiber mixture to the air-permeable endless belt 20 together with the air flow. The first carrier sheet supply means 40 supplies the first carrier sheet 41 toward the air-permeable endless belt 20. The second carrier sheet supply means 50 supplies the second carrier sheet 51 toward the first carrier sheet 41 which has passed through the air permeable endless belt 20. The suction box 60 sucks the permeable endless belt 20 from the inside thereof.

  In the web forming apparatus 1, the fiber mixture supply means 30 is installed above the permeable endless belt 20, and the first carrier sheet supply means 40 is installed upstream of the permeable endless belt 20, and the second carrier sheet The supply means 50 is disposed downstream of the air permeable endless belt 20.

  In the web forming process using the web forming apparatus 1, the conveyor 10 is driven to rotate the air-permeable endless belt 20 by rotating the rollers 11 in the same direction. Further, the first carrier sheet 41 is fed out from the first carrier sheet supply means 40 so as to be in contact with the air permeable endless belt 20.

  Then, while suctioning the air-permeable endless belt 20 by the suction box 60, the fiber mixture is lowered with the air flow from the fiber mixture supply means 30, and the fiber mixture is dropped onto the first carrier sheet 41 on the air-permeable endless belt 20. , Deposit. Thereby, the air-laid web W is formed. The air-laid web W thus formed becomes the web layer of the nonwoven fabric sheet according to the present embodiment. If the basis weight of the web layer is high, the water containing the acidic component can be retained for a long time.

  Next, the second carrier sheet 51 is supplied from the second carrier sheet supply means 50 onto the air-laid web W to obtain an air-laid web-containing laminated sheet.

(Binding process)
The bonding method is preferably a thermal bonding method from the viewpoint of bonding without using water. The binding step by the thermal bonding method is a step of heating the air-laid web to bind the disaggregated short cut fibers with the heat-fusible resin.

  Examples of the heat treatment of the air-laid web include hot air treatment and infrared irradiation treatment, and in terms of low cost of the apparatus, hot air treatment is preferred.

  As the hot air treatment, the air-laid web is brought into contact with a through-air dryer provided with a rotating drum having air permeability on its circumferential surface and heat-treated (hot air circulation rotary drum system) or the air-laid web is passed through a box type dryer The method (Hot-air circulation conveyor oven system) etc. which heat-process by letting hot air pass an air laid web are mentioned.

  When the air-laid web is sandwiched between the first carrier sheet and the second carrier sheet to form a laminated sheet as in the present embodiment, the laminated sheet may be subjected to hot air treatment as it is. The first carrier sheet and the second carrier sheet can be peeled off from the air laid web after the hot air treatment. The heat treatment temperature may be a temperature at which the heat fusible resin melts. For example, when using materials such as PP and PE generally used for a thermal bonding method, it is desirable to set the heating temperature to 115 ° C. or higher.

  After the binding step, in order to finely adjust the thickness and density of the non-woven fabric sheet, it may be compressed through a heating roll.

(Formation of functional substance-containing layer)
The manufacturing method of the nonwoven fabric sheet concerning the 3rd mode of this embodiment is explained. The nonwoven fabric sheet which concerns on a 3rd aspect has a layer (functional material containing layer) containing the powder which exhibits acidity when it contacts with water | moisture content. In the present embodiment, the functional substance-containing layer is a layer provided by a dry method. The dry method that can be used in the present embodiment includes a non-water-based arbitrary layer forming method that does not use water. The same manufacturing method can be adopted for any other functional substance-containing layer, which contains a powder exhibiting alkalinity when in contact with moisture.

(Method of applying dye solution to carrier)
The functional substance-containing layer of the nonwoven fabric sheet of the present embodiment contains a pH indicator (hereinafter also referred to as a pigment) in a form fixed to a carrier. For this purpose, a step of applying a dye to the carrier is performed. A method of applying a pH indicator mixed solution (dye solution) to a carrier, which can be used in the embodiment of the present invention, will be described.

  The method of applying the dye to the non-woven fabric sheet can be roughly divided into the following methods from the viewpoint of the process of applying the dye to the carrier.

  Specifically, there is a method of first carrying a pigment on a component (for example, cellulose fiber etc.) constituting a layer to which a pH indicator is to be blended in a non-woven fabric sheet, and then sheeting it as a raw material. For example, there is a method of adding a dye mixture solution while stirring with a cellulose fiber mixer or the like to obtain cellulose fibers with the dye solution coated on the surface as a raw material for forming a sheet.

  Alternatively, there is a method in which the dye solution is applied to the surface of the nonwoven sheet after the nonwoven sheet is prepared. For example, there is a method of coating a sheet surface by spraying (spraying) a dye solution at the time of forming a non-woven sheet. In addition to the coating, the dye solution may be applied to the carrier by impregnation.

  In addition, the sheeting process itself of a structural component can be performed according to the above-mentioned nonwoven fabric sheet manufacturing method demonstrated about the 1st and 2nd aspect.

(solvent)
Non-aqueous solvents (organic solvents) such as aromatic hydrocarbons, aliphatic hydrocarbons, esters, alcohols and the like can be mentioned as examples of solvents applicable for producing a dye solution (pH indicator mixed solution) . A drug (pH indicator, quaternary ammonium salt, and, as appropriate, a binder, etc.) to be a constituent material of the dye solution can be dissolved to prepare a uniform dye solution, and after the carrier is coated with the dye solution, It is preferable that the solvent be removable by a technique such as vacuum drying. In particular, alcohols are preferred, and furthermore, isopropyl alcohol is preferred.

(Blended amount)
The compounding amount of the dye (pH indicator) varies depending on the dye to be used, but it is preferable that a clear color change is observed upon use. For example, the blending amount of thymol blue is preferably 0.01 to 0.5% (w / w), more preferably 0.02 to 0.1% (w / w) based on the weight of the carrier. In addition, a carrier here means the component (fiber, powder, etc.) of the functional substance containing layer in which the pH indicator is mix | blended among non-woven fabric sheets.

  The blending amount of the binder is preferably 3% (w / w) or less, more preferably 2% (w / w) or less based on the weight of the carrier. If the amount is more than 3%, the water-repellency of the dye-carrying carrier becomes high, the solution is difficult to penetrate, and the color developability tends to deteriorate.

  The amount of quaternary ammonium is preferably 0.05 to 5% (w / w), more preferably 0.1 to 2%, based on the weight of the carrier. For example, benzalkonium chloride is commercially available from the manufacturer in the form of an aqueous solution such as a 10% aqueous solution and a 50% aqueous solution, but the above figures are the amount of solid content as benzalkonium chloride .

  The above-mentioned blending amount can be optimized according to the blending amount of each drug. For example, when 2% (w / w) of the binder is blended with respect to the weight of the carrier, the blending amount of benzalkonium chloride is 0.1 to 0.5% (w / w) with respect to the weight of the carrier It is good to do. When no binder is blended, the blending amount of benzalkonium chloride is preferably 0.3 to 2% (w / w) based on the weight of the carrier.

  That is, although the composition which does not mix a binder is included in the embodiment of the present invention, by blending a binder, it is possible to reinforce the fixation of the pH indicator to the carrier, and benzalkonium chloride The amount can be reduced.

  The blending amount of the solvent is preferably 10 to 100% (w / w), more preferably 15 to 50% (w / w) based on the weight of the carrier. When the blending amount of the solvent is small, the viscosity of the dye solution becomes high and uniform mixing with the carrier becomes difficult. In addition, when the solvent is too much, the processing time of the drying step after mixing the dye solution and the carrier becomes long, which causes the increase of the processing time and the cost.

(Compounding amount of carrier)
The carrier on which the pH indicator I is fixed can be blended in the functional substance-containing layers 140, 150, 160 at an arbitrary ratio. From the viewpoint of the visibility of the color change of the functional sheet, it is preferable that the color change of the pH indicator I can be clearly confirmed.

(Use of non-woven sheet)
Below, the use of the nonwoven fabric sheet which concerns on this Embodiment is illustrated.

  Non-woven sheet applications include (1) for protection, (2) for medical use, (3) for construction materials and civil engineering, (4) for hygiene, (5) for wipers, (6) for agriculture and horticulture, (7) For living materials, (8) for industrial materials, and (9) for experimental materials.

  (1) For protection, for example, protective articles may be mentioned. A specific example of the protective article is a mask or the like.

  (2) For medical use, for example, gauze, a mask, sheets, antibacterial mats, a base for patch, a base for poultice, a therapeutic agent for arousal syndrome and the like can be mentioned.

  (3) For building materials and civil engineering, for example, water-impervious sheets, protective materials, non-contact materials and the like can be mentioned.

  (4) For hygiene purposes, for example, diapers, sanitary products, emergency supplies, cleaning products, hand towels, masks and the like can be mentioned. As a specific example of the said diaper, it is a paper diaper etc. Specific examples of the sanitary product are napkins, tampons and the like. Specific examples of the first aid are gauze, first aid bandages, cotton swabs and the like. Specific examples of the cleaning products include wet tissues, cosmetic cotton, breast milk pads, wiping sheets, sweat absorbing sheets (for face, side, neck, legs, etc.), antibacterial and disinfecting sheets, antiviral sheets, Anti-allergen sheet, antibacterial deodorant sheet, etc. A specific example of the mask is a disposable three-dimensional mask or the like.

  (5) For the wiper, for example, a wiper, a wet wiper, an oil strainer, a copier cleaning material, etc. may be mentioned.

  (6) For agricultural and horticultural use, for example, a sheet for nursery beds, a sheet for solid covering, a sheet for preventing frost, a sheet for preventing grass, a gardening planter and the like can be mentioned. When used for agriculture and horticulture, it can be used, for example, to create an anaerobic environment and perform forced cultivation.

  (7) Examples of household materials include packaging materials, cleaning products, bags, food products, household items, kitchen products, sports products, beauty materials and the like. Specific examples of the cleaning supplies include wipers, chemical wipes, scraps and the like. A specific example of the bag is a desiccant bag or the like. Specific examples for the food are tea bags, coffee bags, food bags, freshness holding materials, sheets for absorbing water for food, carbonated injections, food additives and the like. Specific examples of the household goods are bath salts, eye masks, cold feeling sheets, warm feeling sheets, neck scarves, gloves, deodorizing sheets, fragrance base materials, insect repellents, pet sheets and the like. Specific examples of the kitchenware include a draining sheet, a fire extinguishing cloth and the like. A concrete example of the sporting goods is a fatigue recovery material and the like. The beauty materials include face masks, puffs, beauty packs, beauty gloves and the like.

  (8) For industrial materials, for example, industrial materials, electric materials, batteries, product materials, OA devices, AV devices, rolls, device members and the like can be mentioned.

  (9) For experimental materials, for example, anaerobic environment-forming materials, anesthetics, insect attractants and the like can be mentioned.

  The nonwoven fabric sheet of the present embodiment can be suitably used particularly for cleaning sheets, household material sheets, cosmetic sheets, and medical and hygiene sheets such as gauze. Also, without being limited to the above classification, the same nonwoven sheet can be used in a wide variety of fields and applications.

  Hereinafter, the present embodiment will be more specifically described by way of examples and comparative examples, but the present embodiment is not limited to the following examples.

(Evaluation test)
The nonwoven fabric sheets of Examples, Comparative Examples, and Experimental Examples were manufactured as follows, and the performance was evaluated.

<Evaluation item and test method>
I. Water Retentiveness When the non-woven fabric sheet contains water, the non-woven fabric sheet applies the liquid containing the acidic component to the object to be cleaned for a long time as the ability to retain the contained water (water retentivity) is higher. Is considered possible. The water retentivity may be judged, for example, by the amount of water that can be taken into the interior when water is contained in the nonwoven fabric sheet, the length of time that the taken-in water can be kept inside, etc. it can.

  Here, the water retention was evaluated according to the following procedure. First, each of the nonwoven fabric sheets (5 cm by 5 cm) of the examples and comparative examples is made to contain a predetermined amount (2 ml) of water, and then lightly squeezed, and the nonwoven sheet can not be held and the amount of water overflowing is visually observed It confirmed by. Furthermore, the non-woven fabric sheet after lightly squeezing was placed on the surface to be cleaned (the surface of the tile measuring 15 cm square) and left for a predetermined time (5 minutes). During this time, the surface to be cleaned was inclined with respect to the horizontal, and the presence or absence of water (liquid dripping) overflowing from the nonwoven fabric sheet and dripping was visually confirmed.

  It was evaluated that the lower the amount of overflowing water, the higher the water retention and the better.

  In addition, although it confirmed visually here, as an alternative method, the quantity of the water which a nonwoven fabric sheet hold | maintains, and its fluctuation | variation are confirmed by measuring the weight of the nonwoven fabric sheet in each step with a meter. It is also good.

II. Performance concerning dirt removal When the surface to be cleaned is wiped with a non-woven sheet, the number of wipings until the dirt is removed is less, and the smaller the amount of force that needs to be applied to remove the dirt, the dirt on the non-woven sheet It is considered that the performance to drop

  Here, a wiping operation was performed to wipe the surface to be cleaned with a non-woven fabric sheet containing water, and the state of soiling was visually confirmed. When the dirt was not removed, the wiping operation was repeated with substantially the same force as the previous one. The performance with respect to soil removal was evaluated based on the number of wiping operations until the soil was removed.

  Specifically, assuming a water stain, 1 ml of a 0.1% aqueous solution of calcium hydroxide is sprayed in advance to adhere to the surface of a tile measuring 15 cm by 15 cm in the form of a mist, and the temperature is kept constant at 23 ° C. and 50% RH. It was left to solidify under constant humidity conditions for 2 hours. The same operation was repeated a total of five times. Hereinafter, the stain solidified in this manner is referred to as "water stain".

  With the surface of the tile to which the scale was attached as the cleaning target surface, the non-woven fabric sheet was placed on the cleaning target surface according to the same procedure as the water retention test described above and left for a predetermined time (5 minutes) . Then, the wiping operation was performed by wiping the surface of the tile on which the nonwoven fabric sheet was placed with the nonwoven fabric sheet placed on the surface. The wiping operation was repeated until the water scale was completely removed, up to a maximum of 10 times.

  The less the number of wiping operations before the dirt was removed, the higher the performance regarding dirt removal was evaluated as being better.

III. Stickiness There is a method of using a non-woven fabric sheet containing water in contact with a surface to be cleaned and leaving it as it is, and performing a wiping operation after a certain amount of time has elapsed. According to this method, it is possible to intensively apply a liquid containing an acidic component to the portion of the surface to be cleaned which the non-woven fabric sheet contacts. According to this, the dirt adhering to the surface to be cleaned can be floated, and the cleaning efficiency is considered to be high.

  By the way, the surface to be cleaned is not necessarily horizontal, and may not necessarily be flat and curved, or may include corners and irregularities. In order to obtain the above-mentioned effects, the non-woven fabric sheet can be deformed along the shape of the surface to be cleaned to be in contact with the surface to be cleaned, and the state can be maintained for a certain period of time , Stickiness is required.

  Here, the following two points were visually confirmed as sticking properties.

  (1) In the above-described water retention evaluation test, the cleaning target surface (the surface of the tile) was inclined to the horizontal when confirming the presence or absence of dripping, but at this time, the nonwoven fabric sheet is from the cleaning target surface Whether it can stay without slipping or peeling off.

  (2) Assuming that a sink is a cleaning object as one example, a non-woven fabric sheet in which water is made to dive quickly adheres along the shape to the corner portion (surface to be cleaned) of the sink It stuck and it left to stand for a predetermined time (1 minute). At this time, whether or not the non-woven fabric sheet can be maintained as it is when it is attached without peeling off from the surface to be cleaned.

  In any of the above (1) and (2), it is desirable that the non-woven fabric sheet does not peel off from the surface to be cleaned, and the smaller the change in the relative position of the non-woven fabric sheet to the surface to be cleaned, the better the adhesion. It was evaluated.

IV. Colorability: color change, clearness of color change, and dye runoff property When water is contained in a non-woven sheet containing a functional substance such as a powder that exhibits acidity when contacted with water and a pH indicator (pigment) The reaction of functional substances changes the hydrogen ion concentration (pH) in water. The pH indicator (pigment) incorporated in the sheet reacts in response, and the color or color changes, and the color of the sheet changes. The color corresponding to pH and the clarity of the color change may differ depending on the type and the amount of the pH indicator (pigment) and the like. In addition, if the pH indicator (pigment) does not stay in the sheet due to water and flows out of the sheet, color transfer may occur in water, the sheet may be lightened, and the color change may not be clear.

  Here, as an indicator of the colorability of the sheet, tests were conducted using a sheeting raw material in a form in which a pH indicator (pigment) was fixed to cellulose fibers as a carrier instead of the sheet. As pH indicators, several ones that change in the acidic to weakly alkaline region were tested. Specifically, according to the following procedure, the coloration (color change, clearness of color change, and color outflow) of the sheeting raw material was visually confirmed.

  (1) The dye-coated cellulose fibers 2 and 3 obtained in the experimental examples described later each contained a 5-fold amount (mass basis) of a pH adjuster (acidic, neutral, alkaline).

0.1 N sulfuric acid (pH 1.4) was used as an acidic pH adjuster. As a neutral pH adjuster, 1 M phosphate buffer (pH 7.0) was used. 0.1% Ca (OH) ₂ (pH 2.0) was used as an alkaline pH adjuster.

  (2) The color change of the cellulose fibers 2 and 3 by the pH adjuster, the clearness of the color change, and the outflow of the dye to the liquid were visually confirmed.

  Thereby, for each pH indicator, it was grasped what color the cellulose fiber exhibited in response to the pH. The clearer the color change, the more easily the user perceives the pH change when in use when applied to the non-woven sheet, which is preferred. In addition, the smaller the dye outflow, the clearer the color change of the sheet, the easier it is to recognize the pH change, and the smaller the influence of the material outflow on the environment. The effect of the presence or absence of blending of the binder to the dye solution was confirmed for the dye efflux.

V. Colorability of Sheet: Color Change, and Dye Outflowability The following tests were conducted on the non-woven fabric sheet of the example (specifically, example 4) containing a pH adjuster among the examples described later.

(Confirmation of color change)
The formed sheet was cut into a size of 5 cm × 5 cm square, and water was included in an amount of 5 times the sheet weight. At this time, the color and pH of the sheet were confirmed before (dry), immediately after, 15 minutes, and 60 minutes after the addition of water.

(Dye spillage)
The white plastic sheet was wiped with a colored sheet as one index of dye run-out and color transfer was visually confirmed. Here, "color transfer" means that a pigment which is a coloring component of a sheet is eluted out of the sheet and transferred to a plastic sheet. The smaller the degree of color transfer, the lower the dye outflow and the more preferable. More preferably, the color transfer can not be confirmed.

Example 1
<Manufacture of non-woven sheet>
Short cut rayon fiber (fineness 3.3 dtex, fiber length 5 mm) and short cut core-sheath type heat-sealable composite fiber (PET / PE composite core-sheath fiber, fineness 2.2 dtex, fiber length 5 mm, sheath melting point 130 ° C. ) Were subjected to disintegration processing using a swirl flow jet air flow disintegration device to obtain disintegrated short cut fibers.

  Next, rayon fibers in the form of disintegrated short cut fibers and heat-fusible composite fibers in the form of open disintegrated short cut fibers are uniformly mixed by an air flow at a ratio (mass ratio) of 70/30 to make rayon / ( A fiber mixture of PET / PE) was obtained.

  Citric acid (average particle diameter 100 μm) and PE powder (average particle diameter 400 μm) were mixed at a ratio (mass ratio) of 80/20 to obtain a particle mixture of citric acid / PE powder.

  Then, using the web forming apparatus 1 shown in FIG. 4 on a carrier sheet, a sheet having an air-laid web formed using a fiber mixture was obtained.

Specifically, a rayon spunlace nonwoven fabric (basis weight 27 g / m ² , air permeability 292 cm ³ / cm) is provided by the first carrier sheet supply means 40 on the air-permeable endless belt 20 mounted on the conveyor 10 and traveling. The 1st carrier sheet 41 which consists of ² / s) was drawn out.

While suctioning the air-permeable endless belt 20 by the suction box 60, PE powder is sprayed so as to be 5 g / m ² on the first carrier sheet 41, and the air flow from the fiber mixture supply means 30 is thereon. The above fiber mixture was dropped and deposited. At that time, the fiber mixture was supplied so that the basis weight per air laid web portion would be 150 g / m ² .

Then, a particle mixture of citric acid / PE powder was sprayed onto the air laid web at 50 g / m ² and deposited. A second carrier sheet consisting of a rayon spunlace nonwoven fabric (basis weight 27 g / m ² , air permeability 292 cm ³ / cm ² / s) was laminated thereon, to obtain an air-laid web-containing laminated sheet.

The obtained laminated sheet was passed through a box type drier of a hot air circulating conveyor oven system and subjected to hot air treatment at 140 ° C. to obtain a non-woven sheet having a basis weight of 259 g / m ² .

Example 2
<Manufacture of non-woven sheet>
Short-cut core-sheath type heat-sealable composite fiber (PET / PE composite core-sheath fiber, fineness 2.2 dtex, fiber length 5 mm, sheath melting point 130 ° C.) is broken using a swirl flow jet air flow fibrillation device The fiber was treated to obtain a defibrated shortcut fiber.

  Next, the fibers of pulp / (PET / PE) are uniformly mixed with a soft chemical pulp and a heat-fusible composite fiber in the form of a defibrated shortcut fiber at a ratio of 70/30 (mass ratio) by an air flow. A mixture was obtained.

  Then, using the web forming apparatus 1 shown in FIG. 4 on a carrier sheet, a sheet in which an air-laid web was formed using a fiber mixture and citric acid (average particle diameter 100 μm) was obtained.

Specifically, a rayon spunlace nonwoven fabric (basis weight 27 g / m ² , air permeability 292 cm ³ / cm) is provided by the first carrier sheet supply means 40 on the air-permeable endless belt 20 mounted on the conveyor 10 and traveling. The 1st carrier sheet 41 which consists of ² / s) was drawn out.

While suctioning the air-permeable endless belt 20 by the suction box 60, PE powder is sprayed so as to be 5 g / m ² on the first carrier sheet 41, and the air flow from the fiber mixture supply means 30 is thereon. Together with the above fiber mixture and citric acid in a ratio of 135/15 (mass ratio) while dropping and depositing. At that time, the fiber mixture and citric acid were supplied so that the basis weight per air laid web portion would be 150 g / m ² .

Next, PE powder was sprayed and deposited on the air-laid web at 5 g / m ² . A second carrier sheet consisting of a rayon spunlace nonwoven fabric (basis weight 27 g / m ² , air permeability 292 cm ³ / cm ² / s) was laminated thereon, to obtain an air-laid web-containing laminated sheet.

The obtained laminated sheet was passed through a box type drier of a hot air circulating conveyor oven system and subjected to hot air treatment at 140 ° C. to obtain a nonwoven fabric sheet having a basis weight of 214 g / m ² .

[Example 3]
<Manufacture of non-woven sheet>
A laminated sheet obtained by laminating a tissue (14 g / m ² basis weight) made of wood pulp as a second carrier sheet instead of a rayon spunlaced non-woven fabric is a hot air circulating conveyor oven type box type dryer A film (PE, 26 g / m ² basis weight) coated with 5 g / m ² of a hot melt adhesive (ethylene-vinyl acetate copolymer) by hot-air treatment at 140 ° C. A sheet was obtained in the same manner as in Example 1 except that lamination was performed so that the surface on which the hot melt adhesive was applied faces the tissue. The basis weight was about 277 g / m ² .

Example 4
<Preparation of dye solution>
50 g of a 2% strength thymol blue solution (solvent: ethanol), 10 g of a 50% strength aqueous benzalkonium chloride solution, and 40 g of polyvinyl butyral were dissolved in isopropanol, and the total amount was 500 g with isopropanol (mass / mass) Criteria). A mixture was prepared by mixing until the polyvinyl butyral was completely dissolved, to give a dye solution C1.

<Application of dye solution to carrier>
While stirring 50 g of powdered cellulose fiber (fiber length 0.2 mm) with a mixer, 25 g of dye solution C1 was added and stirred until the fiber and dye solution were uniformly mixed. Next, the resultant was dried in a dryer at 105 ° C. for 2 hours to remove the solvent, and powdered dye-coated cellulose fiber 1 (fiber length 0.2 mm) was obtained.

<Manufacture of non-woven sheet>
Instead of the particle mixture of citric acid / PE powder, citric acid and PE powder (average particle diameter 400 μm) and dye-coated cellulose fiber 1 are mixed at a ratio (mass ratio) of 70/25/15, citric acid / PE A sheet was obtained as in Example 1 except that a particle mixture of powder / dye coated cellulose fibers was obtained. The basis weight was 185 g / m ² .

Comparative Example 1
A sheet was obtained in the same manner as in Example 1 except that PE powder (average particle diameter 400 μm) was sprayed onto the air-laid web at 5 g / m ^{2 in place of the} particle mixture and deposited. The basis weight was about 214 g / m ² .

Comparative Example 2
Core-sheath type heat-fusible composite fiber (PET / PE composite core-sheath fiber, denier 2.2 dtex, fiber length 5 mm, sheath instead of rayon / (PET / PE) fiber mixture instead of fiber mixture of rayon / (PET / PE) An air-laid web-containing sheet was obtained in the same manner as in Example 1 except that a partial melting point of 130 ° C. was used.

Experimental Examples 1 to 8
<Preparation of dye solution>
First, 1% solutions of each of eight pH indicators (pigments) described in Table 1 below were prepared. At this time, Congo red, indigo carmine, red cabbage pigment was dissolved in water, and the other pigments were dissolved in ethanol to prepare a solution. The materials were then mixed according to the formulations described in Table 2 to prepare two dye solutions C2, C3 for each pH indicator.

(Table 1) pH indicator

(Table 2) Formulation of dye solution (mass / mass basis)

<Application of dye solution to carrier>
While stirring 50 g of powdered cellulose fiber (fiber length 0.2 mm) with a mixer, 25 g of dye solution C2 was added, and the fiber and dye solution were stirred until they were uniformly mixed. Next, the resultant was dried by a dryer at 105 ° C. for 2 hours to remove the solvent, and powdered dye-coated cellulose fiber 2 (fiber length 0.2 mm) was obtained.

  Powdered dye-coated cellulose fiber 3 (fiber length 0.2 mm) was obtained in the same manner as in dye solution C3 except that dye solution C3 was used.

(Test results)
Table 3 shows the evaluation test I.2. ~ III. Show the results of Table 4 shows the evaluation test IV. Show the results of Table 5 shows the evaluation test V.2. Show the results of

(Table 3) Evaluation test I. ~ III. Result of

(Table 4) Evaluation test IV. Result of

(Table 5) Evaluation test V. Result of

The test results are indicated by symbols ○, 、, and x in the order from the one with the highest evaluation. The specific content of the evaluation is as follows.
I. Water retention ○: The water did not overflow when lightly squeezed, and the nonwoven fabric sheet was able to retain the contained water. In addition, when the non-woven fabric sheet was placed on the surface to be cleaned and left to stand, no dripping phenomenon was observed.
X: The water was repelled, the water overflowed before squeezing lightly, and the nonwoven fabric sheet could not hold the contained water.
II. Dirt removal ○: By performing the wiping operation several times, it was possible to wipe off dirt and stains easily.
X: Even if wiping operation was repeated 10 times, the stain could not be wiped off completely. III. Stickability o: The nonwoven fabric sheet did not peel off from the surface to be cleaned.
X: The nonwoven fabric sheet peeled off from the surface to be cleaned.
IV. Colorability ○: The color change was large and clear.
Δ: Color change was visible.
X: The color change was small and unclear.

  As mentioned above, the nonwoven fabric sheet of this embodiment could fully hold the water containing an acidic ingredient. Moreover, the non-woven fabric sheet of the present embodiment was able to float off the scale and easily wipe it off. Furthermore, the non-woven fabric sheet of the present embodiment did not peel off from the surface to be cleaned during application to the surface to be cleaned.

  That is, the non-woven fabric sheet of the present embodiment can be deformed along the shape of the surface to be cleaned while maintaining the water containing the acidic component, and can keep the shape, so the water containing the acidic component Can be effectively applied to the surface to be cleaned.

  Moreover, from Experimental Examples 1 to 8, it was found that the cellulose fiber carrying the pH indicator (pigment) changes its color in response to the pH change. It has been found that by appropriately selecting the pH indicator (pigment) to be used, it can be configured to cause a color change in a desired pH range. In addition, it was found that clear color change can be obtained by properly selecting the pH indicator (pigment) to be used. At this time, it was also found that the tendency of dye outflow for the obtained carrier can be reduced by incorporating a binder into the dye solution for fixing the pH indicator (pigment) to the carrier. This is considered to be because the pH indicator (pigment) and the carrier were more firmly fixed by the binder.

  In Example 4, the non-woven fabric sheet was colored by applying water to the non-woven fabric sheet. When the pH of the water contained in the non-woven fabric sheet changes with time, a clear change in the color of the non-woven fabric sheet was observed according to the change in pH.

  Therefore, in the nonwoven fabric sheet of the present embodiment, by using a carrier on which a pH indicator (pigment) is carried as a component of the nonwoven fabric sheet, a nonwoven fabric sheet whose color changes in response to a change in pH can be obtained. The user can visually recognize that the non-woven fabric sheet exhibits the desired pH range pH and then that the non-woven fabric sheet does not exhibit the desired pH range pH by the color change of the non-woven fabric sheet it can. Therefore, the user can use the non-woven sheet while the non-woven sheet exhibits the pH of the desired pH range (that is, the time suitable for use), and also facilitates the end of use of the non-woven sheet. It can be judged.

DESCRIPTION OF SYMBOLS 1 web forming apparatus 30 fiber mixture supply means 41 first carrier sheet 51 second carrier sheet 100 web layer 110 water absorbing material 140 functional substance containing layer 150 containing heat fusible resin functional substance containing layer 160 fiber Containing functional substance-containing layer 200 Alkaline layer 300 Water-permeable or water-absorbent sheet 350 Other layer 400 Film 1000, 2000, 2010, 2020 Non-woven sheet A, B Heat fusible resin D Functional substance F Fiber I pH indicator (pigment )
W Airlaid Web

Claims (15)

A nonwoven sheet comprising a web layer formed by an air laid method, comprising:
The non-woven sheet comprises a powder that exhibits acidity when in contact with moisture,
The web layer is a non-woven sheet mainly composed of a water absorbing material.   The non-woven sheet according to claim 1, wherein the powder is included in the web layer.   The non-woven fabric sheet according to claim 2, wherein the powder is unevenly distributed on one side of the web layer in the thickness direction of the web layer.   The nonwoven fabric sheet according to claim 2, wherein the powder is uniformly distributed in the thickness direction of the web layer.   The nonwoven fabric sheet according to claim 1, wherein the powder is laminated in a layer form on the web layer.   The nonwoven fabric sheet according to any one of claims 1 to 5, wherein the web layer is mainly composed of a water absorbing fiber.   The non-woven fabric sheet according to any one of claims 1 to 6, wherein the non-woven fabric sheet comprises a particulate heat-fusible resin having a particle size of 1 μm to 1000 m.   The nonwoven fabric sheet according to any one of claims 1 to 7, wherein the web layer contains a fibrous heat-fusible resin having a fineness of 1 dtex to 120 dtex and an average fiber length of 1 mm to 100 mm.   The non-woven sheet according to any one of claims 1 to 8, wherein the non-woven sheet comprises a water-permeable or water-absorbent sheet adjacent to the web layer.   The non-woven fabric sheet according to claim 5, wherein the non-woven fabric sheet comprises a water-permeable or water-absorbent sheet adjacent to the powder arranged in a layer in contact with the web layer.   The nonwoven fabric sheet according to any one of claims 1 to 10, wherein a film layer made of a film is provided on one surface of the nonwoven fabric sheet.   The non-woven fabric sheet according to any one of claims 1 to 11, wherein the non-woven fabric sheet further comprises an alkaline layer containing a powder exhibiting alkalinity when in contact with moisture.   The non-woven sheet according to any one of the preceding claims, wherein the web layer comprises the water-absorbing material in an amount of more than 60% by weight based on the weight of the web layer. The non-woven sheet contains a pH indicator and a carrier in the same layer as the powder,
The non-woven fabric sheet according to any one of claims 1 to 13, wherein the pH indicator is fixed to the carrier by a quaternary ammonium salt.   The nonwoven fabric sheet according to claim 14, further comprising a binder, wherein the pH indicator is fixed to the carrier by the quaternary ammonium salt and the binder.

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