WO2018016646A1

WO2018016646A1 - Sheet of nonwoven fabric

Info

Publication number: WO2018016646A1
Application number: PCT/JP2017/026571
Authority: WO
Inventors: 昴藤村; さくら本多; 夕子齋藤; 寿子得能
Original assignee: 王子ホールディングス株式会社
Priority date: 2016-07-22
Filing date: 2017-07-21
Publication date: 2018-01-25
Also published as: TW201809390A; US20190284738A1; JPWO2018016646A1

Abstract

Provided is a sheet of nonwoven fabric having excellent cleaning performance. The sheet of nonwoven fabric includes a web layer formed by an air-laid method. The sheet of nonwoven fabric includes powder producing alkalinity when in contact with moisture, and has a water-absorbing material as a main component.

Description

Nonwoven sheet

The present embodiment relates to a nonwoven fabric sheet, and more particularly, to a nonwoven fabric sheet containing a material that exhibits alkalinity when contacted with water. The non-woven fabric sheet of the present embodiment is suitable for use in cleaning, in particular, affixed to a cleaning object and used for wiping off at the time of cleaning, and is preferably used in the field of cleaning products and miscellaneous goods. it can.

A sheet containing a material that exhibits alkalinity when wetted with water is conventionally known. For example, Patent Document 1 is mainly composed of an airlaid nonwoven fabric in which an alkaline inorganic salt powder, a heat-adhesive fiber, and optionally a cellulosic pulp are blended, which exhibits alkalinity when wet with water, and a heat-fusible fiber. A cleaning sheet in which a nonwoven fabric is laminated is disclosed.

Japanese Patent No. 4671794

The cleaning sheet of Patent Document 1 has a laminated structure in which a nonwoven fabric layer mainly composed of heat-fusible fibers is an essential component. Therefore, the cleaning sheet has a certain degree of rigidity as a whole, and it is difficult to wipe off the curved surface portion and the corner portion of the object to be cleaned, and the cleaning performance may not be sufficient.

In addition, in a sheet containing a material that exhibits alkalinity by being wetted with water, when the sheet does not exhibit a desired pH due to a chemical reaction of the material exhibiting alkalinity or outflow from the sheet, etc. after a period of time has passed since wetting with water Come. Then, when the user continues to use the sheet, a desired wiping and cleaning effect cannot be obtained.

An object of the present invention is to provide a nonwoven fabric sheet having excellent cleaning performance. It is a further object of the present invention to provide a non-woven sheet that can easily recognize a suitable time for use.

An embodiment of the present invention for solving the above problems has the following aspects.
1. A non-woven sheet including a web layer formed by an airlaid method, wherein the non-woven sheet includes a powder exhibiting alkalinity when contacted with moisture, and the web layer is mainly composed of a water-absorbing material.
2. The powder is contained in the web layer. The non-woven fabric sheet described in 1.
3. 1. The powder is unevenly distributed on one surface side of the web layer in the thickness direction of the web layer. The non-woven fabric sheet described in 1.
4). 1. The powder is uniformly distributed in the thickness direction of the web layer. The non-woven fabric sheet described in 1.
5. The powder is layered on the web layer. The non-woven fabric sheet described in 1.
6). The web layer is mainly composed of water-absorbing fibers. To 5. The nonwoven fabric sheet in any one of.
7). The nonwoven fabric sheet includes a particulate heat-fusible resin having a particle size of 1 μm or more and 1000 μm or less. To 6. The nonwoven fabric sheet in any one of.
8). The web layer includes 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. To 7. The nonwoven fabric sheet in any one of.
9. The nonwoven sheet includes a water-permeable or water-absorbent sheet adjacent to the web layer. To 8. The nonwoven fabric sheet in any one of.
10. 4. The nonwoven fabric sheet includes a water-permeable or water-absorbent sheet adjacent to the powder that is disposed in contact with the web layer. The non-woven fabric sheet described in 1.
11. 1. A film layer made of a film was provided on one surface of the nonwoven fabric sheet. To 9. The nonwoven fabric sheet in any one of.
12 The non-woven fabric sheet further includes an acidic layer containing a powder that exhibits acidity when contacted with moisture. To 11. The nonwoven fabric sheet in any one of.
13. The nonwoven sheet contains a pH indicator and a carrier in the same layer as the powder,
The pH indicator is fixed to the carrier with a quaternary ammonium salt. To 12. The nonwoven fabric sheet in any one of.
14 12. A binder is further included, wherein the pH indicator is fixed to the carrier by the quaternary ammonium salt and the binder. The non-woven fabric sheet described in 1.
15. The same layer includes fibers, and the carrier in which the pH indicator is fixed and the powder are held in voids formed by the fibers. Or 14. The non-woven fabric sheet described in 1.
16. The same layer includes a heat-fusible resin, and a part of the carrier on which the pH indicator is fixed is fixed in a state of being covered with the heat-fusible resin. . To 15. The nonwoven fabric sheet in any one of.
17. The adjacent layer adjacent to the same layer includes a heat-fusible resin, and is fixed in a state where a part of the carrier to which the pH indicator existing in the same layer is fixed is coated with the heat-fusible resin. 13. It is characterized by the above-mentioned. To 16. The nonwoven fabric sheet in any one of.
18. 12. The quaternary ammonium salt is at least one selected from the group consisting of benzil chloride, cetyl pyridinium chloride, benzethonium chloride, and didecyl dimethyl ammonium salt. To 17. The nonwoven fabric sheet in any one of.
19. 12. The carrier for fixing the pH indicator is cellulose and / or a cellulose derivative. To 18. The nonwoven fabric sheet in any one of.
20. 13. The binder is a water-insoluble polymer compound, To 19. The nonwoven fabric sheet in any one of.
21. 13. To 20. A method for producing a nonwoven fabric sheet according to any one of
Dissolving the pH indicator and the quaternary ammonium salt in a non-aqueous organic solvent;
Applying the solution obtained by the step to the carrier;
The manufacturing method of the nonwoven fabric sheet characterized by including this.
22. Further comprising the step of forming the carrier into a sheet,
20. The step of applying is performed before the step of forming the sheet, The manufacturing method as described in.
23. Further comprising the step of forming the carrier into a sheet,
20. The imparting step is performed after the step of forming the sheet. The manufacturing method as described in.

The nonwoven fabric sheet containing powder that exhibits alkalinity when contacted with moisture in the embodiment of the present invention is a nonwoven fabric sheet including a web layer formed by an airlaid method, and the web layer is mainly composed of a water-absorbing material. In the nonwoven fabric sheet of the aspect of the present invention, since the web layer is mainly composed of a water-absorbing material, when water is included, the web layer is easily deformed along the surface to be cleaned of the object to be cleaned. Adhesiveness is good and excellent cleaning performance is exhibited.

Moreover, the nonwoven fabric sheet containing a powder exhibiting alkalinity (hereinafter also referred to as “alkaline powder”) when in contact with moisture according to another aspect of the present invention further includes a pH indicator in a form fixed to a carrier. When water is applied to the nonwoven fabric sheet, the alkaline powder comes into contact with the water and exhibits alkalinity. At this time, the pH indicator changes color (color development) or changes color according to the change in the hydrogen ion concentration, thereby changing the color of the nonwoven fabric sheet. The user can visually recognize that the non-woven fabric sheet has a desired pH and that the non-woven fabric sheet no longer exhibits 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 exhibits a desired pH (that is, a time suitable for use), and easily determines the end time of use of the non-woven sheet. be able to.

FIGS. 1 (a) to 1 (k) are diagrams showing a configuration example of a nonwoven fabric sheet according to the first and third aspects of the present invention. 1 (a) and 1 (b) are diagrams showing a configuration example of a nonwoven fabric sheet according to the second and third aspects of the present invention. 1 (a) to 1 (f) are diagrams showing a configuration example of a nonwoven fabric sheet according to a specific embodiment of the present 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 embodiment of this invention.

<Nonwoven fabric sheet>
The nonwoven fabric sheet which concerns on embodiment of this invention is a nonwoven fabric sheet containing the web layer formed by the airlaid method, Comprising: The said nonwoven fabric sheet contains the powder which exhibits alkalinity when it contacts with a water | moisture content, The said web layer is The main feature is a water-absorbing material. In an embodiment of the present invention, the web layer of the nonwoven sheet is based on the mass of the entire web layer, the amount exceeding 50% by mass, preferably the amount exceeding 60% by mass, more preferably the amount exceeding 65% by mass, More preferably, the water-absorbing material is contained in an amount of 70% by mass or more. The nonwoven fabric sheet may contain a heat-fusible resin.

The nonwoven fabric sheet according to an 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 being.

Hereinafter, the present embodiment will be described with reference to the drawings. However, the present embodiment is not limited to these embodiments. In the drawings, the same reference numerals indicate the same components. For the same component, a duplicate description may be omitted.

[First embodiment]
FIG. 1 is a diagram illustrating the configuration of the nonwoven fabric sheet according to the first and third aspects of the present embodiment for illustrative purposes, not for limiting purposes. 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. FIG. The web layer 100 is mainly composed of a water absorbent material 110 (not shown). A powder 120 (not shown) that exhibits alkalinity when contacted with moisture is blended in the web layer 100. For example, the web layer 100 is made of a web material containing a water-absorbing material 110, a powder 120 that exhibits alkalinity when in contact with moisture, and a heat-fusible resin 130 (not shown) in a sheet form by an airlaid method. It can be formed through a process of depositing and thermally bonding the heat-fusible resin 130 to bond the components. In the manufacturing process of the nonwoven fabric sheet of the present invention, the reaction between the powder 120 exhibiting alkalinity when contacted with water and water is prevented by using the airlaid method which is a dry method.

In the web layer 100, the powder 120 that exhibits alkalinity when in contact with moisture is fixed in a state where a part thereof is covered with the heat-fusible resin 130. Therefore, the powder 120 exhibiting alkalinity when contacted with moisture is difficult to fall off from the nonwoven fabric sheet 1000, and the powder 120 can contact with moisture when the nonwoven 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 blended in a particulate form, the nonwoven fabric sheet is more flexible than when blended in a fibrous form, and the shape of the object to be cleaned in a cleaning application 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 nonwoven fabric sheet, and the scraping property tends to be excellent in cleaning applications. Further, the smaller the blending amount of the heat-fusible resin, the higher the flexibility of the nonwoven fabric sheet and the lower the rigidity. Therefore, the form and blending amount of the heat-fusible resin in the nonwoven fabric sheet can be appropriately set according to the target performance. The heat-fusible resin in the fibrous form and the heat-fusible resin in the particulate form may be used in combination.

In the present embodiment, the powder 120 exhibiting alkalinity when in contact with moisture is contained in the nonwoven fabric sheet 1000 itself. Therefore, the user of the nonwoven fabric sheet 1000 can save the trouble of separately blending the cleaning agent himself or applying it to the dirt.

In the present embodiment, the web layer 100 of the nonwoven fabric sheet 1000 is mainly composed of a water-absorbing material. Therefore, when water is applied to the nonwoven fabric sheet 1000, the nonwoven fabric sheet 1000 absorbs and holds water, thereby preventing outflow of water and the nonwoven fabric sheet 1000 is relatively flexible. Therefore, even if the surface to be cleaned (for example, a surface with dirt) of the object to be cleaned is a corner portion or a curved surface, the nonwoven fabric sheet 1000 is attached to the surface to be cleaned of the object to be cleaned or wiped off the dirt. Can be. Thereby, the component which exhibits alkalinity can be effectively applied with respect to a cleaning target object, and it can make it easy to float and to remove dirt.

The

nonwoven fabric sheets

1010 and 1020 illustrated in FIG. 1B and FIG. 1C have a multilayer structure including the web layer 100, and the web layer 100 is mainly composed of the water-absorbing material 110. In this example, a water-permeable or water-absorbent sheet 300 that covers one or both sides of the web layer 100 and has a property of passing moisture (water permeability) and / or a property of absorbing moisture (water absorption) is provided. ing. When the nonwoven fabric sheet includes a plurality of water-permeable or water-absorbent sheets 300, these are not necessarily the same material. Hereinafter, the water-permeable or water-absorbent sheet is also simply referred to as a water-absorbent sheet. In this example, the web layer 100 and the water-absorbent sheet 300 are adjacent to each other, and each layer includes a heat-fusible resin and / or a binder separately provided between the layers. The entire surface is joined by thermal fusion. In the present embodiment, the joining may be performed by means such as physical entanglement of the constituent fibers of each layer. Moreover, the web layer 100 and the water absorbing sheet 300 may be joined not partially but entirely.

1 (b) and 1 (c), the same effect as the nonwoven fabric sheet having the configuration shown in FIG. 1 (a) can be obtained.

That is, in the present embodiment, the powder 120 exhibiting alkalinity when in contact with moisture is contained in the nonwoven fabric sheet itself. Therefore, the user of the nonwoven fabric sheet can save the trouble of separately blending the cleaning agent himself or applying it to the dirt.

In this embodiment, the web layer 100 of the nonwoven fabric sheet is mainly composed of a water-absorbing material. Therefore, when water is applied to the nonwoven fabric sheet, the nonwoven fabric sheet can prevent outflow of water by absorbing and holding water. Moreover, the nonwoven fabric sheet is relatively flexible. Therefore, even if the surface to be cleaned (for example, a surface with dirt) of the object to be cleaned is a corner portion or a curved surface, the nonwoven fabric sheet can be attached to the surface to be cleaned of the object to be cleaned or wiped off the dirt. can do. Thereby, the component which exhibits alkalinity can be effectively applied with respect to a cleaning target object, and it can make it easy to float and to remove dirt.

In addition, in the structure of FIG.1 (b) and FIG.1 (c), in addition to the web layer 100, the water-permeable or water-absorbing sheet 300 is included. Therefore, the flexibility of the nonwoven fabric sheet is affected by the properties of the water-permeable or water-absorbent sheet 300 and the ratio of the water-permeable or water-absorbent sheet 300 to the nonwoven fabric sheet. When the flexibility of the water-permeable or water-absorbent sheet 300 itself is high, the nonwoven fabric sheet including the water-permeable sheet 300 tends to have a high suitability for applications to be applied along the surface to be cleaned. Moreover, when the rigidity of the water-permeable or water-absorbent sheet 300 itself is high, the nonwoven fabric sheet including the water-permeable sheet 300 tends to have a high suitability for use in scraping off dirt during cleaning. Moreover, the influence of the property of the water-permeable or water-absorbent sheet 300 increases as the proportion of the water-permeable or water-absorbent sheet 300 in the nonwoven fabric sheet increases.

Moreover, according to the structure of FIG.1 (b) and FIG.1 (c), in addition to the said effect, the possibility of the powder fall-off from the nonwoven fabric sheet of the powder 120 which exhibits alkalinity when it contacts with moisture further Can be reduced.

The

nonwoven fabric sheets

1030 and 1040 shown in FIG. 1 (d) and FIG. 1 (e) are relatively different from one water-permeable or water-absorbent sheet 300 in the configuration shown in FIG. 1 (b) and FIG. 1 (c). Shows a configuration in which the film 400 with low air permeability is replaced. Each web layer 100 of the

nonwoven fabric sheets

1030 and 1040 is mainly composed of the water-absorbing material 110. In the structure having the layer of the low-breathable film 400 on one side, in addition to the effects similar to the structures shown in FIGS. 1B and 1C, the side of the water film containing the alkaline component generated during use The effect that the outflow from the surface and the evaporation of water are prevented can be obtained. Moreover, the strength of the nonwoven fabric sheet can be obtained and the film can be easily handled by the bonding of the film.

The nonwoven fabric sheet 1000 according to the first aspect of the present invention has been described above using FIGS. 1 (a) to 1 (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 that exhibits alkalinity when contacted with moisture is dispersed in the web layer 100 so as to be uniformly distributed in the thickness direction of the layer due to the presence of the water-absorbing material 110 or the web layer 100. Can be unevenly distributed on one side of the surface. Furthermore, the water absorbing material 110 can absorb and retain moisture. Therefore, when the nonwoven fabric sheet 1000 is used, the alkaline component generated by the reaction between the powder 120 and moisture can be kept on the nonwoven fabric sheet for a certain period of time, and good detergency can be obtained.

Further, in the web layer 100, particularly when the water absorbent material 110 is in a fibrous form, the powder 120 is easily maintained in the layer due to the presence of the water absorbent material 110. Moreover, the nonwoven fabric sheet 1000 becomes easy to maintain a shape by the water absorbing material 110 being included in the web layer 100. Therefore, it is possible to improve the yield of the powder 120 during manufacturing, storage and use of the nonwoven fabric sheet 1000, and to prevent powder falling even when the nonwoven fabric sheet 1000 undergoes deformation such as folding. Can do. Therefore, loss of the powder 120 exhibiting alkalinity when in contact with moisture is prevented, leading to cost reduction. Further, the cost can be reduced by selecting the water-absorbing material itself.

The configuration of the nonwoven fabric sheet according to the first aspect of the present invention has been described above using FIGS. 1 (a) to (e). However, these are merely examples, and other configurations and combinations of the configurations are also included in the scope of the present invention.

1 (f) to 1 (k) show a non-limiting example of a modification of the nonwoven fabric sheet 1000 according to the first aspect of the present invention for illustrative purposes. When the nonwoven fabric sheet shown in FIG. 1 (f) to FIG. 1 (k) is brought into contact with moisture in addition to the web layer 100 containing the powder 120 exhibiting alkalinity when the water-absorbing material 110 is the main component and brought into contact with moisture. It further includes an acidic layer 200 containing a powder exhibiting acidity.

The nonwoven fabric sheet of this invention by this structure exhibits alkalinity when in contact with moisture contained in the web layer 100 by moistening the surface on the web layer 100 side of both surfaces of the nonwoven fabric sheet with water during use. The powder 120 comes into contact with moisture and exhibits alkalinity. In addition, during use, the surface of the non-woven fabric sheet on the acidic layer 200 side is moistened with water, so that the powder that is acidic and comes into contact with moisture contained in the acidic layer 200 comes into contact with moisture. Presents.

In general, oil stains, hand dings, hot water odors, garbage smells, and grilled fish are known as acidic stains. In addition, water stains, rust, soap residue, dirt inside electric pots, urine stones, cigarette odors, tobacco dust, etc. are known as alkaline dirt. It is also known that when the acidic soil is neutralized with alkali and the alkaline soil is neutralized with acid, the cleaning effect is high.

By selectively using the surface of the nonwoven fabric sheet on the web layer 100 side for acidic stains and the surface of the nonwoven fabric sheet on the acidic layer 200 side for alkaline stains, acidic stains and alkaline Good detergency is obtained for both stains.

In such a method of use, it is preferable that the self-neutralization reaction in the nonwoven fabric sheet during use, that is, the reaction between the alkaline component in the web layer 100 and the acidic component in the acidic layer 200 does not easily occur. For this reason, the web layer 100 and the acidic layer 200 have a thick layer structure, or are separated between the web layer 100 and the acidic layer 200 as shown in FIGS. 1 (g), 1 (h), and 1 (j). A structure including these layers is preferable. Moreover, a self-neutralization reaction can be reduced by giving water so that a small amount of water may contact only one side of a nonwoven fabric sheet at the time of use.

Alternatively, there is another method of using a self-neutralization reaction in the nonwoven fabric sheet during use. Specifically, when carbonate and / or bicarbonate is used as the powder 120 exhibiting alkalinity when in contact with moisture, both the web layer 100 and the acid layer 200 are obtained by including water in the nonwoven fabric sheet during use. The components react to generate carbon dioxide, which increases the effect of floating dirt when applied to a clean object.

[Second embodiment]
FIG. 2 is a diagram showing the configuration of the nonwoven fabric sheet 2000 according to the second and third aspects of the present embodiment for the purpose of illustration and not for the purpose of 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 sheets

2010 and 2020 according to the second aspect of the present embodiment illustrated in FIGS. 2A and 2B are layered on the web layer 100 and one surface of the web layer 100. Powder 120 that exhibits alkalinity when contacted with moisture. That is, in the nonwoven fabric sheet 1000 according to the first aspect, the powder 120 exhibiting alkalinity when contacted with moisture was included in the web layer 100, but in the nonwoven fabric sheet 2000 according to the second aspect, the moisture and The powder 120 that exhibits alkalinity when in contact is disposed in contact with the web layer 100. The web layer 100 is mainly composed of a water absorbing material 110.

The laminated structure of the web layer 100 and the powder 120 is, for example, forming a web layer by depositing a web material containing a water-absorbing material 110 and a heat-fusible resin 130 in a sheet form by an airlaid method. It is formed through a step of further depositing a mixture of powder 120 exhibiting alkalinity when contacted with moisture and particulate heat-fusible resin, and thermally melting the heat-fusible resin. be able to. In the non-woven fabric sheet of the present embodiment, the reaction between the powder 120 exhibiting alkalinity and water when contacted with moisture is prevented by using a dry method in the production process. The layer of the powder 120 that is laminated on one surface of the web layer 100 and exhibits alkalinity when in contact with moisture is hereinafter 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 is obtained. That is, in this Embodiment, the powder 120 which exhibits alkalinity when it comes into contact with moisture is contained in the nonwoven fabric sheet 2000 itself. Therefore, the user of the nonwoven fabric sheet 2000 can save the trouble of separately blending the cleaning agent himself or applying it to the dirt. Moreover, in this Embodiment, the web layer 100 of the nonwoven fabric sheet 2000 mainly consists of a water absorbing material. Therefore, when water is applied to the nonwoven fabric sheet 2000, the nonwoven fabric sheet 2000 absorbs and holds water, thereby preventing outflow of water, and the nonwoven fabric sheet 2000 is relatively flexible. Therefore, even if the surface to be cleaned (for example, a surface with dirt) of the object to be cleaned is a corner portion or a curved surface, the nonwoven fabric sheet 2000 is attached to the surface to be cleaned of the object to be cleaned or wiped off the dirt. Can be. Thereby, the component which exhibits alkalinity can be effectively applied with respect to a cleaning target object, and it can make it easy to float and to remove dirt.

In addition, in the nonwoven fabric sheet 2000 of the second aspect, in addition to the web layer 100 and the powder 120 laminated in a layer on one surface of the web layer 100 and exhibiting alkalinity when in contact with moisture, moisture The structure which further comprises the acidic layer 200 containing the powder which exhibits an acidity when contacting with can be taken.

The nonwoven fabric sheet of the present embodiment according to the configuration of this modification has a surface on the web layer 100 side of the nonwoven fabric sheet for acidic stains, and a surface on the acidic layer 200 side of the nonwoven fabric sheets for alkaline stains. When used selectively, good detergency can be obtained for both acidic soils and alkaline soils. In this method of use, it is preferable that the self-neutralization reaction in the nonwoven fabric sheet during use, that is, the reaction between the alkaline component and the acidic component does not occur. For that purpose, it is preferable that the acidic layer 200 is provided on the opposite side of the surface of the web layer 100 opposite to the surface on which the powder 120 exhibiting alkalinity when it is in contact with moisture.

Alternatively, there is another method of using a self-neutralization reaction in the nonwoven fabric sheet during use. Specifically, when carbonate and / or bicarbonate is used as the powder 120 that exhibits alkalinity when it comes into contact with moisture, both the alkaline and acidic components react when water is contained in the nonwoven fabric sheet during use. Carbon dioxide is generated, and the effect of floating dirt when applied to a clean object is enhanced.

[Third Aspect]
With reference to FIG. 1 and FIG. 2 again, the configuration of the nonwoven fabric sheet (nonwoven fabric) of the third aspect of the present embodiment will be described. In the drawings, the same reference numerals indicate the same components. For the same component, repeated description may be omitted.

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

In the configuration example shown in FIGS. 1A to 1K, the powder 120 (not shown) that exhibits alkalinity when contacted with moisture is contained in the web layer 100 as described above. Becomes an alkaline powder-containing layer. Further, in the configuration example shown in FIGS. 2A and 2B, the powder 120 exhibiting alkalinity when in contact with moisture is contained in the particle layer in contact with the web layer 100. The layer becomes an alkaline powder-containing layer. The alkaline powder-containing layer includes a powder 120 that exhibits alkalinity when contacted 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 configuration of “the pH indicator is contained in the nonwoven fabric sheet”, unless otherwise specified, “the pH indicator is contained in a form fixed to a carrier”. Assume the composition. When “the pH indicator is contained in a form fixed to the carrier”, the pH indicator compounded in the nonwoven sheet may of course be fixed to the carrier, but the total amount is not necessarily limited. It may not be fixed to the carrier. That is, the nonwoven fabric sheet may contain a pH indicator that is not fixed to the carrier. One kind of powder and pH indicator that exhibit alkalinity when contacted with moisture can be included, and the present invention is not limited to this, and multiple types are included in the same layer and / or different layers of the nonwoven fabric sheet. Can be.

As shown in FIGS. 1 (f) to 1 (k), the nonwoven fabric sheet has an acidic layer (hereinafter, also referred to as “acidic powder-containing layer”) 200 containing a powder that exhibits acidity when contacted with moisture. In the above, the pH indicator can also be added to the acidic powder-containing layer. Also in the acidic powder-containing layer, it is desirable that the pH indicator is blended in a form fixed to a carrier.

Since the pH indicator is contained in a form fixed to the carrier, the pH indicator can be easily mixed in a desired layer of the nonwoven fabric sheet, and the pH indicator can be prevented from flowing out of the nonwoven fabric sheet during use. .

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

Coloring or discoloration in response to a pH change when the non-woven sheet comes into contact with moisture by adding a pH indicator to the same layer as the alkaline powder-containing layer (and the acidic powder-containing layer, if present) Can do.

For easy recognition of color change, the nonwoven fabric sheet according to the embodiment of the present invention has a configuration in which the alkaline powder-containing layer and / or the acidic powder-containing layer (if present) is the outermost layer, or the outermost layer is alkaline. Even if it is other layers other than a powder containing layer, it has the structure which can visually recognize the color of an alkaline powder containing layer from the outside through another layer. For example, the other layer may have a mesh structure or a perforated structure, or may have a thin thickness, a material that is translucent or transparent, and the lower layer can be seen through.

The alkaline powder-containing layer and / or acidic powder-containing layer may contain a fiber, a heat-fusible resin, an effect accelerator, and the like in addition to the pH indicator and the alkaline powder and / or acidic powder. Each of the fiber, the heat-fusible resin, and the effect accelerator may be one kind or plural kinds.

Specific examples as shown below will be described as an example of a configuration for preventing pH indicator and alkaline powder and / or acidic powder from falling off the nonwoven fabric sheet. Hereinafter, the alkaline powder and / or the acidic powder are also collectively referred to as “functional substances”. Further, the alkaline powder-containing layer and / or the acidic powder-containing layer is also collectively referred to as “functional substance-containing layer”.

(First specific embodiment)
FIG. 3A is an example in which the functional substance-containing layer includes fibers F. FIG. In the functional substance-containing layer 160 containing the fibers F, the functional substance D is prevented from falling off by being held in the voids formed by the fibers F, that is, the voids in the fiber structure formed by the fibers F. ing. The pH indicator I can be held on the nonwoven fabric sheet by fixing the fiber F as a carrier. Alternatively, the pH indicator I uses a material different from the fiber F as a carrier, and is held in a void in the fiber structure formed by the fiber F in a form fixed to the carrier F, like the functional substance D. Can do. Alternatively, both may be used. Details of the carrier will be described later.

The functional substance-containing layer 160 containing fibers may 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 fibers may contain a heat-fusible resin, an effect accelerator, and the like. Further, the fiber F itself may be a heat-fusible resin.

(Second specific embodiment)
FIG. 3B shows 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 fixing) while being partially 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 covered state when the molten heat-fusible resin A is solidified. As a result, powder falling is prevented. The heat-fusible resin A is blended in such an amount that does not cover the entire pH indicator I and the functional substance D. The pH indicator I and the functional substance D are covered with the heat-fusible resin A. It has a part that is not made, and contact with water and elution are guaranteed when the sheet is used.

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. The functional material-containing layer 140 containing a heat-fusible resin contains fibers, an effect accelerator, and the like in addition to the pH indicator I, the functional material D, and the heat-fusible resin A. Also good. Further, the heat-fusible resin itself may be fibrous.

(Third specific embodiment)
FIG. 3C shows an example in which the layer adjacent to the functional substance-containing layer contains the heat-fusible resin B. The layer 200 including the heat-fusible resin B adjacent to the functional substance-containing layer 150 is disposed on the surface of the functional substance-containing layer 150 and the heat-fusible resin B is heated by heat. It was 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 thereof is covered with the heat-fusible resin B. Note that the heat-sealable resin A included in the layer 140 and the heat-sealable resin B included 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 coated when the heat-fusible resin B melted in the layer 200 containing the heat-fusible resin B adjacent thereto is solidified. By being fixed, powder fall-off is prevented. Moreover, the functional substance D has a part which is not coat | covered with the heat-fusible resin B, and the contact and elution with water at the time of sheet | seat use are ensured.

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 included, the layer 200 containing the heat-fusible resin B is heated by placing a mixture of the heat-fusible resin B and these other components on the surface of the functional substance-containing layer 150. Can be obtained by melting the heat-fusible resin B.

Specifically, the nonwoven fabric sheet of the example shown in FIG. 3C 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. And a functional substance-containing layer 140 including the functional substance D and the heat-fusible resin A. In the case of this example, the functional substance-containing layer 140 can also contribute to the prevention of powder falling of the pH indicator I and the functional substance contained in the functional substance-containing layer 150 positioned as an intermediate layer.

Here, a functional substance-containing layer 150 composed 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 formed, and the constituent materials, pH indicator I, functional substance, and heat-fusible resin A are unevenly distributed in the thickness direction. A configuration in which the one functional substance-containing layer 140 is also included in this embodiment. According to this aspect, in particular, when a powdery material is unevenly distributed on one surface side of the functional substance-containing layer 140, the layer 200 is disposed adjacent to the surface to effectively eliminate powder. Can be prevented.

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

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

In this aspect, the nonwoven fabric sheet is, for example, for the purpose of imparting functionality such as surface modification or strength (rigidity) imparting, among the outer surfaces of the laminate of the functional substance-containing layer and the layer 200 including the heat-fusible resin B It may have a multilayer structure (not shown) in which another layer 350 is laminated on one side or both sides. In that case, the other layer 350 has a configuration that does not hinder the visual recognition of the color change of the nonwoven fabric sheet.

(Fourth aspect)
The nonwoven fabric sheet according to the above-described embodiment of the present invention may be formed by heat sealing. As an example, FIG. 3D shows a configuration in which another layer 350 containing a heat-fusible resin is laminated on both surfaces 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 capable of recognizing the color of the functional substance-containing layer 150 through the other layer 350.

(5th 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 an 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 as to prevent the powder of the pH indicator I and the functional substance D contained in the functional substance-containing layer 150 from being removed. For example, a hot melt adhesive Etc.

Specifically, in the nonwoven fabric sheet of the example shown in FIG. 3E, an adhesive layer 500 made of a hot melt adhesive such as a thermoplastic resin is provided between the functional substance-containing layer 150 and the other layer 350. It has a configuration in which an interlayer is bonded by hot melt processing.

More specifically, the nonwoven 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. The active material-containing layer 140 is included. Also in the nonwoven fabric sheet of the example shown in FIG. 3 (e), the functional substance-containing layer 140 including the heat-fusible resin A is positioned as an intermediate layer, as in the example of FIG. 3 (c). The pH indicator I and the functional substance contained in the functional substance-containing layer 150 can contribute to prevention of powder falling off. Further, here, the functional substance-containing layer 150 and the functional substance-containing layer 140 containing the pH indicator I and the heat-fusible resin A are illustrated and described as separate layers, but these two layers are integrated with each other. The configuration in which the pH indicator I, which is a constituent material, the functional substance, and the heat-fusible resin A is configured as a single constituent of the functional substance-containing layer 140 is also provided. Included in embodiments. According to this aspect, in particular, when powdered material is unevenly distributed on one surface side of the functional substance-containing layer 140, the layer 500 is disposed adjacent to the surface to effectively eliminate powder. Can be prevented.

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

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

In the above, the structure of the nonwoven fabric sheet of this invention was demonstrated using Fig.3 (a) to (f). However, these are merely examples, and other configurations, for example, combinations of the exemplified 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 fibers F, or the functional substance-containing layer 140 containing the heat-fusible resin A, or Further, it may be a layer containing both 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 tier)
The nonwoven fabric sheet of this Embodiment contains the web layer formed by the airlaid method. In the present embodiment, the web layer 100 is mainly composed of a water-absorbing material, and based on the mass of the entire web layer, the amount exceeds 50% by mass, preferably exceeds 60% by mass, more preferably 65% by mass. The water-absorbing material 110 is included in the above amount, more preferably 70% by mass or more.

(Water-absorbing material)
The nonwoven fabric sheet of the present embodiment is mainly composed of a water-absorbing material. Water-absorbing materials include natural fibers such as pulp, hemp, cotton, silk, wool and mineral fibers, regenerated fibers such as rayon, and fibrous water-absorbing materials such as synthetic fibers such as polylactic acid and nylon (water-absorbing fibers). ) Can be used. The water-absorbing fiber can be used, for example, in the form of a defibrated chopped fiber. The average fiber length of the water absorbent fibers is preferably 1 to 100 mm, more preferably 1 to 60 mm, and even more preferably 2 to 30 mm. Further, the fineness of the water-absorbing fiber is preferably 1 dtex to 120 dtex, and more preferably 1 dtex to 85 dtex. Further, when the average fiber length and fineness of the water-absorbing fibers are in the above ranges, the web layer can be easily formed and a uniform dispersed state can be easily obtained. 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 be used as an auxiliary agent. Examples of the water-absorbing resin particles include carboxymethyl cellulose, polyvinyl alcohol, and a polymer absorber (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 within the above range, a uniform dispersion state can be easily obtained.

The web layer of the nonwoven fabric sheet according to the present embodiment is mainly composed of a water-absorbing material, and is preferably composed mainly of a water-absorbing fiber. Powders that exhibit alkalinity when in contact with moisture can be present dispersed or unevenly distributed within the web layer due to the presence of the water-absorbing material.

In addition, the water-absorbing material of the present embodiment contacts and absorbs water and the powder component (alkaline component) dissolved in water while using the nonwoven fabric sheet, and gradually releases it. be able to. Therefore, at the time of use of a nonwoven fabric sheet, the alkaline component produced | generated by reaction with water can be continuously applied over a certain long time with respect to the cleaning object surface of a cleaning object.

(Powder that exhibits alkalinity when in contact with moisture)
The nonwoven fabric sheet of this Embodiment contains the powder which exhibits alkalinity, when it contacts with a water | moisture content. As the powder exhibiting alkalinity when contacted with moisture, alkali inorganic salts such as carbonates or bicarbonates can be used. The alkali inorganic salt can be used without particular limitation as long as it is of a grade that can be used in cosmetics, and no special grade is specified when it is used for applications that do not touch the human body or the like and have no environmental problems. For example, sodium carbonate, sodium bicarbonate, sodium sesquicarbonate, potassium carbonate, potassium bicarbonate, calcium carbonate, magnesium carbonate, magnesium bicarbonate, calcium bicarbonate, or a derivative thereof can be used. Two or more carbonates and / or bicarbonates may be used in combination. In particular, one or both of sodium bicarbonate 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 a form supported on a support such as silica. The alkali inorganic salt may contain water as crystal water. When water of crystallization is included, the solubility in water increases 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 moisture does not contain moisture that causes alteration such as hydrolysis or reaction with acid. As the powder exhibiting alkalinity when in contact with moisture, metal oxides such as calcium hydroxide and sodium hydroxide, metal hydroxides, phosphates, silicates and the like can be used. As the powder exhibiting alkalinity when contacted with moisture used in the present embodiment, particles having an average particle diameter of 5 to 5000 μm are preferable. When the average particle size is 5 to 5000 μm, the dropout of the particles is small, and a good feeling of use can be obtained with an appropriate granular feeling.

In the nonwoven fabric sheet according to the first aspect of the present embodiment, the powder 120 exhibiting alkalinity when in contact with moisture is blended in the web layer 100. Moreover, in the nonwoven fabric sheet which concerns on the 2nd aspect of this invention, the powder 120 which exhibits alkalinity when it contacts with a water | moisture content is arrange | positioned in contact with the web layer 100. FIG. In the present embodiment, the powder exhibiting alkalinity when in contact with moisture can be blended in the web layer and disposed in contact with the web layer. The layer of the powder 120 that is disposed in contact with the web layer 100 and exhibits alkalinity when contacted with moisture is hereinafter simply referred to as a particle layer.

In the nonwoven 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 exhibiting alkalinity when in contact with moisture. In this case, the powder particles exhibiting alkalinity when contacted with moisture and the water-absorbing material can be fixed in the web layer in a state where a part thereof is covered with the heat-fusible resin. Such a web layer is formed when, for example, the surface of a carrier sheet of a web forming apparatus or another layer constituting the nonwoven fabric sheet (for example, a water-permeable or water-absorbent sheet) comes into contact with a water-absorbing material and moisture. It can be formed by depositing a mixture containing powder particles exhibiting alkalinity and a heat-fusible resin, heat-melting the heat-fusible resin, and joining the constituent components.

(Particle layer)
In the nonwoven fabric sheet according to the second embodiment of the present embodiment, the powder 120 exhibiting alkalinity when in contact with moisture can constitute a particle layer disposed in contact with the web layer 100. The particle layer can further contain a heat-fusible resin in addition to the particles of the powder 120 exhibiting alkalinity when in contact with moisture. In this case, the powder particles exhibiting alkalinity when in contact with moisture are fixed in a state where a part thereof is covered with the heat-fusible resin. Such a particle layer is, for example, a mixture of powder particles exhibiting alkalinity when contacted with moisture and a heat-fusible resin on the surface of another layer constituting the nonwoven fabric sheet such as a web layer. It can be formed by thermally melting the heat-fusible resin and bonding the constituent components.

(Heat-fusion resin)
The nonwoven fabric sheet of this Embodiment can contain heat-fusible resin. The heat-fusible resin can be blended in the web layer and / or the particle layer, and at that time, it can function as a constituent material that joins constituent components in the layer and provides strength to each layer. Further, the heat-fusible resin can serve as a binder that is disposed between the layers constituting the nonwoven fabric sheet and adheres the layers.

For example, a heat-fusible resin is uniformly mixed with an alkaline powder (and a water-absorbing material, if included) when contacted with moisture, and is deposited in a layer as one of the layers constituting the nonwoven sheet. When heated and melted, the particle layer (or web layer) covers a part of the powder (and water-absorbing material, if included) that exhibits alkalinity when contacted with moisture. Can be fixed. The heat-fusible resin can be in the form of particles, fibers, or any other form. The heat-fusible resin is preferably in the form of particles from the viewpoint of uniform mixing with the powder (and the water-absorbing material, if included) that exhibits alkalinity when contacted with moisture in the layer forming step. In addition, from the viewpoint of joining a plurality of particles (and / or between fibers) of a powder (and a water-absorbing material, if included) that exhibits alkalinity when it comes into contact with moisture, It is desirable to be fibrous. The heat-fusible resin can be in the form of a shortcut fiber, for example. Various types of heat-fusible resins may be used in combination.

Examples of the heat-fusible resin include 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 (PP) made of a copolymer, a polypropylene made of a copolymer 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 Examples thereof include low-melting polylactic acid having a melting point of ˜150 ° C. and polybutylene succinate having a melting point of 115 ° C. A thermoplastic resin having a melting point exceeding 110 ° C. is preferably used in the present embodiment. Two or more kinds of heat-fusible resins may be used in combination.

When the heat-fusible resin is fibrous, the fineness of the heat-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 further preferably 2 to 30 mm. When the fineness and average fiber length of the heat-fusible fiber are within the above ranges, the web layer can be easily formed, and a uniform binding force and a dispersed state can be easily obtained.

When the heat-fusible resin is in the form of particles, the average particle size of the heat-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 a range that does not completely cover the powder exhibiting alkalinity when in contact with the moisture used.

(Heat-fusion resin composite)
The above heat-fusible resin may be a composite of two or more components. For example, core-sheath fibers in which resins having different melting points are combined, side-by-side fibers using different resins in a cross section perpendicular to the longitudinal direction, and core-shell particles having a core and a shell are included. Among these, core-sheath fibers are preferably used because different types of resins can be easily combined.

As the core-sheath fiber, a core-sheath fiber having a melting point of the sheath part lower than that of the core part is preferably used. For example, a PP / PE composite core-sheath fiber provided with 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.

Other core sheath fibers include, for example, PET / low melting point PET composite core sheath fiber, high density polyethylene / low density polyethylene composite core sheath fiber, polyethylene / low melting point PET composite core sheath fiber, polyamide / low melting point polyamide composite. Examples include core-sheath fibers, polylactic acid / low melting point polylactic acid composite core-sheath fibers, and polylactic acid / polybutylene succinate composite core-sheath fibers.

Many common core-sheath fibers have a melting point of the sheath part exceeding 110 ° C., and such core-sheath fibers are preferably used in the present embodiment.

When the core-sheath fiber having a lower melting point of the sheath part than the melting point of the core part is used for the nonwoven fabric sheet of the present embodiment, when heated to a temperature that is equal to or higher than the melting point of the sheath part and lower than the melting point of the core part, The resin in the sheath part melts and the resin in the core part maintains its shape. As a result, the molten resin in the sheath part retains carbonate and / or bicarbonate in the carbonate layer and / or retains acid in the acid layer, and the water-absorbing material and the fibers in the core part. The effect which binds the structural components of the structure comprised by this is shown. Therefore, the nonwoven fabric sheet according to the present embodiment can provide a sheet strength that is soft and excellent in strength by providing sheet strength after ensuring voids in the sheet.

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

(Acidic layer)
As a modification example included in the scope of the present embodiment, it is possible to adopt a configuration further including an acidic layer containing a powder that exhibits acidity when contacted with moisture. At this time, carbonate and / or bicarbonate is used as the powder exhibiting alkalinity when it comes into contact with moisture blended in the nonwoven fabric sheet. According to the configuration of this modified example, when water is applied at the time of use, the powder that exhibits acidity when in contact with moisture and carbonate and / or bicarbonate contained in separate layers are dissolved in water. Together they generate carbon dioxide. According to the nonwoven fabric sheet of this modification, when applied to the surface to be cleaned of a cleaning object, dirt can be lifted by carbon dioxide gas, and good cleaning performance can be obtained.

As a powder that exhibits acidity when it comes into contact with moisture, it can be used without particular limitation as long as it is an acid of a grade that can be used in cosmetics, and when used in applications that do not touch the human body etc. 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 a derivative thereof, a substance that is hydrolyzed to generate an acid, and the like can be used. Two or more acids may be used in combination. The acid is a solid composition, and is preferably in the form of particles, for example. Hereinafter, in the present specification, a powder that exhibits acidity when contacted with moisture is also simply referred to as acid particles. The acid may contain water as crystal water. When water of crystallization is included, the solubility in water increases and the reactivity is improved. However, from the viewpoint of storage stability, it is preferable that the acidic layer does not contain moisture that causes alteration, such as hydrolysis and a reaction with carbonate and / or bicarbonate. As the acid used in the present embodiment, particles having an average particle diameter of 5 to 5000 μm are preferable. When the average particle size is 5 to 5000 μm, the dropout of the particles is small, and a good feeling of use can be obtained with an appropriate granular feeling. When the average particle size is reduced, the dissolution rate is increased, and the reaction proceeds immediately after being wetted with water, so that the amount of CO ₂ gas generated in the initial stage of use is increased. Moreover, the granular feeling which can affect the usability | use_condition of a nonwoven fabric sheet can be reduced. On the other hand, increasing the average particle size has the effect of extending the duration of carbon dioxide gas generation because dissolution gradually proceeds when contacted with water. In addition, increasing the average particle diameter has the effect of reducing particle dropout.

The acidic layer may further contain a heat-fusible resin in addition to the acid particles. In this case, the acid particles are fixed in a state where a part thereof is covered with the heat-fusible resin in the acidic layer. Such an acidic layer, for example, arranges a mixture of acid particles and a heat-fusible resin on the surface of one of the other layers constituting the nonwoven fabric sheet, and melts the heat-fusible resin by heat. Can be formed.

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

(Effect promoter)
One or a plurality of effect accelerators can be blended in the nonwoven fabric sheet of the present embodiment depending on the application.

Examples of the effect promoter include: oily base, moisturizer, touch improver, surfactant, polymer, thickener / gelator, solvent, propellant, antioxidant, reducing agent, oxidizing agent, preservative , Antibacterial agents, chelating agents, pH adjusters, acids, alkalis, powders, inorganic salts, UV absorbers, whitening agents, vitamins and their derivatives, anti-inflammatory agents, anti-inflammatory agents, hair-growth agents, blood circulation promoters, Stimulants, hormones, anti-wrinkle agents, anti-aging agents, squeeze agents, cooling sensations, warming sensations, wound healing promoters, stimulation relieving agents, analgesics, cell activators, plant / animal / microbe extracts, antipruritics , Exfoliating / dissolving agent, antiperspirant, refreshing agent, astringent, enzyme, nucleic acid, fragrance, pigment, colorant, dye, pigment, metal-containing compound, unsaturated monomer, polyhydric alcohol, polymer additive Anti-inflammatory analgesic, antifungal, antihistamine, hypnotic sedative, tranquilizer, antihypertensive Agents, antihypertensive diuretics, antibiotics, anesthetics, antibacterial substances, antiepileptics, coronary vasodilators, herbal medicines, adjuvants, wetting agents, thickeners, tackifiers, antidiarrheals, keratin softening release agents, Examples thereof include oily raw materials, ultraviolet ray blocking agents, antiseptic disinfectants, antioxidant substances, liquid matrices, fat-soluble substances, polymer carboxylates, additives, metal soaps, and the like.

The effect promoter can be blended in the web layer. If the nonwoven sheet has a layer separate from the web layer, it can also be added to one or both of the web layer and the other layer.

(Water-permeable or water-absorbent sheet)
As the water-permeable or water-absorbent sheet 300 of the present embodiment, an arbitrary sheet is used among a sheet having a property of passing moisture (water permeability) and a sheet having a property of absorbing moisture (water absorption). it can. As a sheet | seat which has the property (water permeability) which lets a water pass, it is only necessary to let water pass through and there is no limitation. As the sheet having the property of absorbing moisture (water absorption), a sheet that can take in and retain moisture and release the moisture inside can be used. That is, it can be said that the sheet | seat which has the property (water absorption) which absorbs the water | moisture content which can be applied to this Embodiment is a kind of sheet | seat which has the property (water permeability) which lets water pass. The water-permeable or water-absorbent sheet 300 has a water absorption rate of 60 seconds or less, more preferably 30 seconds or less, measured according to the sedimentation rate measurement method defined in the JIS L1907 standard. Alternatively, the water absorption (or water passage) speed by the dropping method specified in the JISL1907 standard is 60 seconds or less, and more preferably 30 seconds or less. In the water-permeable or water-absorbent sheet 300, the lower the water absorbency, the faster the speed of water passage. In the nonwoven fabric sheet using the water-absorbent sheet 300, the reaction between the powder 120 exhibiting alkalinity and water quickly comes into contact with moisture. The water containing the alkaline component can be generated in a short time. Further, the water-permeable or water-absorbent sheet 300 can retain water containing an alkaline component for a longer time as the water absorption (moisture retention) increases.

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

As a water-permeable or water-absorbent sheet used on the surface, the use of a thick sheet or a low-density sheet has an effect of providing wet strength and scraping performance to the nonwoven fabric sheet. On the other hand, if a thin sheet or a sheet with high water permeability and air permeability is used, it is difficult to prevent moisture from entering from the surface of the nonwoven fabric sheet and outflow of water containing the generated alkaline component to the outside. Easy to get effect. A water-permeable or water-absorbent sheet is appropriately selected according to the use and purpose.

In addition, for the purpose of imparting design properties and improving the wiping property when used as a cleaning article, the surface of the water-permeable or water-absorbent sheet that is the outer layer of the nonwoven fabric sheet may be subjected to surface treatment such as unevenness. A plurality of water-permeable or water-absorbent sheets may be used in an overlapping manner.

(the film)
When using a nonwoven fabric sheet as the film 400, the film 400 has flexibility so that it can be applied along the surface to be cleaned (including corners and curved surfaces) of the object to be cleaned, and other layers of the nonwoven sheet. In particular, any film having a relatively low air permeability as compared with 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 an alkaline component generated during use of the non-woven sheet from the surface on which the film is disposed and preventing the evaporation of moisture. Therefore, by applying the surface opposite to the surface on the film arrangement side to the surface to be cleaned, there is an effect that water containing an alkaline component can be applied to the application site for a long time. For example, the air permeability measured by the “fabric and knitted fabric test method” 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. / S or less film can be used. This air permeability is the amount of air permeating the film per unit area and unit time when a predetermined pressure is applied, and the larger the value, the higher the air permeability. By using a film having a relatively low air permeability as compared with other layers of the non-woven sheet, in particular, a water-permeable or water-absorbent sheet, carbon dioxide gas permeation can be directed.

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

(Other layers)
In addition to the web layer 100 and the functional substance-containing

layers

140, 150, and 160, the nonwoven fabric sheet according to the present embodiment includes other layers 350 for the purpose of imparting functionality such as surface modification and strength (rigidity). Can be included.

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

The other layer 350 may contain a heat-fusible resin. When the other layer 350 contains a heat-fusible resin, the heat-fusible resin contained in the other layer 350 may be the same as or different from the above-mentioned heat-fusible resins A and B. It may be one type or a combination of a plurality of types.

When a film having relatively low water permeability is used on one surface of the functional substance-containing sheet, it is possible to prevent the functional component from eluting from the surface when the sheet is used. That is, it can promote that the component of a functional substance elutes from the other surface. When a transparent or translucent film is used, the color change of a nonwoven fabric sheet can be easily visually recognized from the outside.

The surface of another layer 350 serving as the outer layer of the functional substance-containing sheet may be subjected to surface processing such as providing irregularities or processing such as formation of holes or slits. For applications such as mats for food trays, for example, a perforated film or a film having slits in which a large number of holes such as a surface material of a sanitary material are formed on one or both surfaces of a functional substance-containing sheet is preferable. Can be used. With such a configuration, the functional substance can be easily eluted by the holes and slits when the sheet is used, and the drip from the food can be sucked into the inner layer of the functional substance-containing sheet. .

(Heat seal processing)
Heat sealing is a method in which heat is applied by a heating means such as a heat sealer to bond the layers. In the embodiment of the present invention, for example, a functional substance-containing layer consisting only of a pH indicator and a functional substance is used as an intermediate layer, and a layer 200 containing a heat-fusible resin is disposed on both sides as another layer 350. And the functional sheet of a multilayer structure can be formed by heat-sealing four sides. At least one of the layers 200 disposed on both surfaces of the functional substance-containing layer has a configuration that allows the user to visually recognize the color change of the functional substance-containing layer via the layer 200. For example, the layer 200 may be transparent or translucent, and may have a mesh structure having a mesh size that prevents the constituent material of the functional substance-containing layer from leaking outside.

(Adhesive layer)
The method for forming the adhesive layer is not particularly limited, but 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 the sheets. It can be used for interlayer adhesion when the functional substance-containing layer and other layers are bonded.

Examples of the thermoplastic resin 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.

(Embossing)
Embossing is a process in which heat is applied with a pressing die carved with uneven patterns. This method can also be used for interlayer adhesion of multilayer structures. Moreover, this method can also be used for applying a surface treatment such as irregularities to a functional substance-containing sheet having a single layer or a 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, bromocresol. Synthetic pigments such as purple (also referred to as bromcresol purple), phenol red, phenolphthalein, cresolphthalein, thymolphthalein, alizarin yellow R, eriochrome black T, and the like. In addition, natural pigments such as red cabbage pigment, perilla pigment, purple potato pigment, red radish pigment, purple corn pigment, elderberry pigment, and grape / blueberry pigment can be used.

These synthetic pigments and natural pigments are generally known and can be purchased from manufacturers. In the present specification, the pH indicator is also simply referred to as a pigment.

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

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

Examples of carriers applicable to the embodiments of the present invention include pulps derived from wood, hemp, cotton, Manila hemp, etc., cellulose materials such as cellulose, hemicellulose, microcrystalline cellulose, ion exchange cellulose, nylon, polyester , Synthetic fibers such as acrylic, kaolin, synthetic silica, glass, aluminum silicate, zeolite, fine powders of clay minerals such as bentonite, starch, protein and the like. The shape of the carrier is not particularly limited and may be particulate or fibrous.

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

The pulp may be wood pulp obtained from wood raw materials such as conifers and hardwoods, and may be non-wood pulp made from non-wood raw materials such as herbs such as cotton and hemp. Wood pulp can be obtained, for example, by processing kraft cooking or the like on wood chips, but the production method is not limited to this, and wood pulp produced by a known method can be used to implement the present invention. Examples of carriers that can be applied to these forms are included.

Microcrystalline cellulose is obtained by hydrolyzing pulp to remove non-crystalline regions, and the main component is crystalline cellulose.

The ion-exchange cellulose is a substance obtained by introducing a positively or negatively charged group into cellulose and imparting properties as an ion exchanger. Examples of ion exchange cellulose include diethylaminoethyl cellulose, carboxymethyl cellulose (CMC), phosphocellulose and the like.

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

Cellulose fibers can be preferably used from the viewpoint of excellent formation and appearance when blended with a nonwoven fabric. The cellulose fibers may be 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 manufactured by Rettenmeier has products with an average fiber length of 18 μm to 2.2 mm, and cellulose fibers having a suitable fiber length can be used.

Powdered cellulose fiber can be used for dye coating treatment without pretreatment, but sheet-like cellulose fiber is used as a pretreatment for dye coating treatment after cutting into a size suitable for subsequent mechanical processing, and then defibrated for use. You may do it.

<Quaternary ammonium salt>
The quaternary ammonium salt is added 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.

The quaternary ammonium salt is a salt of a quaternary ammonium cation and another anion. The quaternary ammonium cation is a polyatomic ion having a positive charge represented by the molecular formula NR4 + (wherein R is an alkyl group or an aryl group), and is always charged in a solution regardless of the pH of the solution. It is known as a material. This quaternary ammonium cation is considered to attach the pH indicator to the carrier by a chemical bond such as a surface active action or an ionic bond.

Examples of quaternary ammonium salts applicable to embodiments of the present invention include cetyltrimethylammonium chloride, stearyltrimethylammonium chloride, lauryltrimethylammonium chloride, benzyltrimethylammonium chloride, benzyltriethylammonium chloride, cetylpyridium chloride, Examples include benzalkonium chloride, benzethonium chloride, dialkyldimethylammonium chloride, didecyldimethylammonium chloride, distearyldimethylammonium chloride, and the like. Cetylpyridinium chloride, benzethonium chloride, or didecyldimethylammonium chloride can be preferably used. In particular, benzylzirconium chloride can be preferably used.

<Binder>
The binder is used to immobilize the pH indicator on 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 embodiments of the present invention include cellulose derivatives such as nitrocellulose, cellulose acetate, and ethyl cellulose, or polyester resins, alkyd resins, polyurethane resins, epoxy resins, acrylic resins, vinyl chloride resins, Examples thereof include synthetic resins such as vinyl chloride copolymer resins, polyvinyl butyral resins, polyvinyl acetate emulsions, acrylate copolymer emulsions, vinylidene chloride copolymer emulsions, epoxy resin emulsions, and synthetic rubber latexes.

When a binder is used to fix the pH indicator to the carrier, first, in addition to the pH indicator and the quaternary ammonium salt, the binder is dissolved in a solvent to obtain a pH indicator mixed solution (hereinafter also referred to as a dye solution). To prepare. The dye solution is then coated on the carrier by a method such as spray application or dropping. Thereby, the pH indicator and the quaternary ammonium salt are physically fixed to the carrier.

Since it is mixed as a component of the dye solution, it is preferably a binder having 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. 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 an amount exceeding 50% by mass, preferably exceeding 60% by mass, more preferably not less than 65% by mass, and more preferably based on the mass of the entire web layer. The water-absorbing material is contained in an amount of 70% by mass or more.

The nonwoven fabric sheet of the present embodiment includes a powder that exhibits alkalinity when contacted with moisture. The powder that exhibits alkalinity when contacted with moisture can be blended in and / or in contact with the web layer. The content ratio (X: Y) of the water-absorbing material (X) in the web layer and the powder (Y) exhibiting alkalinity when contacted with moisture in the nonwoven fabric sheet is, for example, more than 50%: 50% on a mass basis. Less than 90%: 10%, preferably more than 60%: less than 40% to 90%: 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 and the total (Y ′ + Z) of the powder (Y ′) and the heat-fusible resin (Z) exhibiting alkalinity when in contact with moisture [X: (Y ′ + Z)] (mass basis) can be, for example, in the range of more than 50%: less than 50% to 90%: 10%, preferably more than 60%: less than 40% to 90%. : 10% of range.

When the ratio is in the above range, the nonwoven fabric sheet has flexibility and can suitably retain moisture during use, and the generated alkaline component can be accurately applied to the surface to be cleaned. Moreover, before use, it can hold | maintain the powder which exhibits alkalinity when it contacts with a water | moisture content in the thickness direction in a web layer, and can suppress a powder fall.

In addition, when it has a layer different from the web layer and the web layer, one or a plurality of effect promoters are blended in an appropriate amount in one or a plurality of the other layers (for example, the particle layer). be able to.

(Content ratio of ingredients)
The compounding amount of the functional substance in the nonwoven fabric sheet (powder that exhibits alkalinity when contacted with moisture, and powder that exhibits acidity when contacted with moisture when contained) depends on the type of material, application, and desired effect. Is also different.

For example, from the viewpoint of the effect of exhibiting a desired function, the blending amount is preferably as large as possible. Further, from the viewpoint of the effect of preventing powder falling, 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 preferably at least mass%, more preferably at least 1 mass%, more preferably at least 3 mass%, further preferably at least 5 mass%, still more preferably at least 8 mass%. More preferably, it is particularly preferably 10% by mass or more. For example, the amount of the powder in the total amount of the sheet is preferably 60% by mass or less, more preferably 50% by mass or less, and further preferably 40% by mass or less.

(Basis weight)
The basis weight of a nonwoven fabric sheet can be suitably set according to a use. For example, the basis weight of the nonwoven fabric sheet is preferably 30 to 300 g / m ² . That is, when the nonwoven fabric sheet has a single-layer configuration composed of a web layer, the basis weight of the web layer itself can be 30 to 300 g / m ² . Moreover, when the nonwoven 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 nonwoven 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 basis weight ratio between the web layer and the water-permeable or water-absorbent sheet 300 and / or the film 400 in the nonwoven fabric sheet can be appropriately set according to the use and the target quality.

<Method for producing nonwoven sheet>
As a manufacturing method of the nonwoven fabric sheet which concerns on the 1st aspect of this Embodiment illustrated by Fig.1 (a), there exists the method of using the web forming apparatus which employ | adopts the generally known airlaid method, for example. For example, on a carrier sheet for conveying a web layer, a uniform mixture of a water-absorbing material, a powder exhibiting alkalinity when in contact with moisture, and a heat-fusible resin such as polyethylene (PE) Each component can be joined by laminating and disposing a carrier sheet thereon and melting the heat-fusible resin by heat treatment. At this time, by using the water-permeable or water-absorbent sheet of the present embodiment for one or both of the two carrier sheets, the layer configuration illustrated in FIG. 1 (b) or FIG. 1 (c) is obtained. Also good. Moreover, the layer structure illustrated in FIG. 1 (d) or FIG. 1 (e) is obtained by using an arbitrary film having a relatively low air permeability as compared with other layers for one of the carrier sheets. 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 this embodiment, these layers are stacked by a dry method in order to prevent a reaction between the powder exhibiting alkalinity when in contact with moisture and water at the time of manufacture. For forming a web layer mainly composed of a water-absorbing material, a web forming apparatus employing a generally known airlaid method can be used.

As a method for manufacturing a nonwoven 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 generally known airlaid method, On the other hand, there is a method using a manufacturing method in which other layers are separately laminated. As such a method, a uniform mixture of powder that exhibits alkalinity when contacted with moisture and fusible binder particles such as polyethylene (PE) is disposed on the surface of the web layer containing the water-absorbing material. The particle layer can be formed by melting and bonding the fusible binder with heat. At this time, when producing a web layer containing a water-absorbing material in a web forming apparatus that employs the airlaid method, the water-permeable or water-absorbing sheet of the present embodiment is used as a carrier sheet for conveying the web layer. You may form a laminated body and obtain the nonwoven fabric sheet which has a layer structure illustrated by Fig.2 (a). Moreover, you may obtain the layer structure illustrated by FIG.2 (b) by using the arbitrary films whose air permeability is relatively low compared with another layer for one of the carrier sheets. The carrier sheet is not essential in the present embodiment, and may be peeled off from the formed laminate after the heat treatment.

Separately produced layers of non-woven sheets may be joined by embossing or heat sealing. There is also a method in which an adhesive layer is provided on at least one of the bonding surfaces of each layer of the nonwoven fabric sheet and the layers are bonded. In the present embodiment, these layers are stacked by a dry method in order to prevent a reaction between the powder exhibiting alkalinity when in contact with moisture during production and water.

(Nonwoven fabric sheet manufacturing method employing airlaid method)
The example of the manufacturing method of the nonwoven fabric sheet of this embodiment which employ | adopts the airlaid method is shown in detail. The method includes a defibrating step, a mixing step, a web forming step, and a binding step.

(Defibration process)
The defibrating step is a step of defibrating a material in the form of a shortcut fiber to obtain a defibrated shortcut fiber by airflow.

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

As the defibrating method, it is preferable to defibrate with a swirling air flow. According to the defibrating method using the swirling air flow, the shortcut fiber can be sufficiently defibrated, and the dispersibility of the defibrated shortcut fiber can be further increased when forming the air laid web by the air laid method. .

As a defibrating method using a swirling air stream, for example, a method of putting a shortcut fiber into a blower and defibrating with a blower can be mentioned. Further, there is a method in which air is sent along a circumferential direction in a cylindrical container by a blower to form a swirling flow, a shortcut fiber is supplied into the swirling flow, and stirring to defibrate.

The flow rate of the air flow is appropriately selected according to the amount of the shortcut fiber, but is usually in the range of 10 to 150 m / sec.

(Mixing process)
The mixing step is a step of obtaining a web raw material by mixing a water-absorbing material in the form of a defibration shortcut fiber and another web layer essential constituent material. In the first aspect of the present embodiment, the other web layer essential constituent material includes a powder exhibiting alkalinity when in contact with moisture. At this time, any other material can be mixed at the same time. The shape of any other material may be fibrous or particulate. Examples of arbitrary other materials include auxiliary agents added as required, such as heat-fusible resins, water-absorbing resin particles, and effect accelerators. There is no particular limitation on the order of addition of these materials, and these materials can be added by, for example, spraying or the like in a step after the mixing step.

In mixing, in order to improve the dispersibility of the defibrating shortcut fiber, it is preferable to stir the defibrating shortcut fiber and other materials. However, in order to prevent breakage of the defibration shortcut fiber, it is preferable to apply stirring using an air flow instead of stirring using mechanical shearing force.

The mixing step may be after the defibrating step or at the same time as the defibrating step. When the mixing step is performed simultaneously with the defibration step, the defibration shortcut fiber and an arbitrary material are mixed using an air flow in the defibration step. Further, arbitrary particles may be introduced into the web forming line of the defibrating shortcut fiber in a particle spraying step described later and mixed.

(Web formation process)
A web formation process is a process of obtaining an airlaid web from a web raw material by the airlaid method. Here, the airlaid method is a method of forming a web by randomly depositing fibers three-dimensionally using an air flow.

(Particle spraying process)
The particle spraying step is a step of blending the powder into the web raw material by a known method. Either a method of mixing powder with fibers to form a web or a method of dispersing on the surface of a web or a carrier sheet may be used. The powder exhibiting alkalinity when in contact with moisture may be dispersed on the surface of the web or on the carrier sheet in this particle dispersion step.

In the web forming process 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, a gas permeable endless belt 20, a fiber mixture supply unit 30, a first carrier sheet supply unit 40, a second carrier sheet supply unit 50, and a suction box 60.

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

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

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

Next, while sucking the permeable endless belt 20 by the suction box 60, the fiber mixture is lowered together 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 permeable endless belt 20. , Deposit. Thereby, the air laid web W is formed. The air-laid web W formed in this way becomes the web layer of the nonwoven fabric sheet according to the present embodiment. When the basis weight of the web layer is large, water containing an alkaline component can be retained for a long time.

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

(Binding process)
As the binding method, it is preferable to use a thermal bond method from the viewpoint of binding without using water. The binding step by the thermal bond method is a step of heat-treating the air laid web and binding the defibrating shortcut fibers with a heat-fusible resin.

The heat treatment of the air laid web includes hot air treatment and infrared irradiation treatment, and hot air treatment is preferable from the viewpoint of low cost of the apparatus.

As the hot air treatment, the air laid web is contacted with a through air dryer provided with a rotating drum having air permeability on the peripheral surface and heat treated (hot air circulating rotary drum method), and the air laid web is passed through a box type dryer. Examples include a method of heat treatment by passing hot air through an air laid web (hot air circulation conveyor oven method).

When the air laid web is sandwiched between the first carrier sheet and the second carrier sheet as in the present embodiment to form a laminated sheet, the laminated sheet may be subjected to hot air treatment. The first carrier sheet and the second carrier sheet can be peeled 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 that are generally used for thermal bonding, it is desirable to set the heating temperature to 115 ° C. or higher.

After the binding step, it may be compressed through a heating roll for the purpose of finely adjusting the thickness and density of the nonwoven fabric sheet.

(Formation of functional substance-containing layer)
The manufacturing method of the nonwoven fabric sheet which concerns on the 3rd aspect of this Embodiment is demonstrated. The nonwoven fabric sheet which concerns on a 3rd aspect has a layer (functional substance content layer) containing the powder which exhibits alkalinity, when it contacts with a 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 this embodiment includes any non-aqueous layer forming method that does not use water. Moreover, the same manufacturing method can be taken also about the layer containing the powder which exhibits acidity when contacting with moisture, which is any other functional substance-containing layer.

(Application method of dye solution to carrier)
The functional substance-containing layer of the nonwoven fabric sheet of the present embodiment includes a pH indicator (hereinafter also referred to as a dye) 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 that can be used in the embodiment of the present invention will be described.

The method of applying the dye to the nonwoven fabric sheet is roughly divided into the following methods from the viewpoint of the step of applying the dye to the carrier.

Specifically, there is a method in which a pigment is supported on a component (for example, cellulose fiber) constituting a layer in which a pH indicator is to be blended in a nonwoven fabric sheet, and then a sheet is formed using the pigment as a raw material. For example, there is a method of adding a dye mixture solution while stirring cellulose fibers with a mixer or the like, and obtaining cellulose fibers whose surface is coated with the dye solution as a raw material for forming a sheet.

Alternatively, there is a method of applying a dye solution to the surface of the nonwoven fabric sheet after preparing the nonwoven fabric sheet. For example, there is a method of coating a sheet surface by spraying a dye solution when forming a nonwoven fabric sheet. In addition to the coating, the dye solution may be applied to the carrier by impregnation.

In addition, the sheet forming process itself of the constituent components can be performed according to the above-described nonwoven fabric sheet manufacturing method described for the first and second aspects.

(solvent)
Examples of solvents applicable for preparing a dye solution (pH indicator mixed solution) include non-aqueous solvents (organic solvents) such as aromatic hydrocarbons, aliphatic hydrocarbons, esters, and alcohols. . A uniform dye solution can be prepared by dissolving a drug (pH indicator, quaternary ammonium salt, and optionally a binder) to be a constituent material of the dye solution, and after coating the dye solution on a carrier, A solvent that can be removed by a technique such as drying under reduced pressure is preferable. In particular, alcohols are preferable, and isopropyl alcohol is more preferable.

(Mixing amount)
The blending amount of the dye (pH indicator) varies depending on the dye to be used, but is preferably such an amount that a clear color change is recognized during use. For example, the amount of thymolphthalein 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 support | carrier here refers to the component (fiber, powder, etc.) of the functional substance content layer in which the pH indicator is mix | blended among nonwoven fabric sheets.

The blending amount of the binder is preferably 3% (w / w) or less, more preferably 2% (w / w) or less with respect to the weight of the carrier. If it is added in an amount of more than 3%, the water repellency of the carrier carrying the dye becomes high, the solution hardly penetrates, 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 manufacturers in the form of aqueous solutions such as 10% aqueous solution and 50% aqueous solution, but the above figures are the amount of solid content as benzalkonium chloride .

The above 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. ). 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, a configuration in which a binder is not blended is also included in the embodiment of the present invention. However, by blending a binder, adhesion of a pH indicator to a carrier can be reinforced, and benzalkonium chloride A compounding quantity can be reduced.

The blending amount of the solvent is preferably 10 to 100% (w / w), more preferably 15 to 50% (w / w) with respect to the weight of the carrier. When the amount of the solvent is small, the viscosity of the dye solution becomes high and uniform mixing with the carrier becomes difficult. On the other hand, when the amount of the solvent is too large, the treatment time of the drying step after mixing the dye solution and the carrier becomes long, which causes an increase in treatment time and cost.

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

Nonwoven sheet uses include (1) protective, (2) medical, (3) building materials and civil engineering, (4) hygiene, (5) wiper, (6) agriculture and horticulture, (7) Examples include daily life materials, (8) industrial materials, and (9) experimental materials.

(1) Examples of protection include protective equipment. A specific example of the protective article is a mask.

(2) Examples of medical uses include gauze, masks, sheets, antibacterial mats, poultice base cloths, poultice base cloths, and hyperalgesia syndrome treatment agents.

(3) Examples of building materials and civil engineering include water shielding sheets, protective materials, and anti-corrosion materials.

(4) Examples of hygiene include diapers, sanitary products, first aid products, cleaning products, towels, masks, and the like. A specific example of the diaper is a paper diaper. Specific examples of the sanitary product include a napkin and a tampon. Specific examples of the emergency supplies include gauze, first-aid plasters, and cotton swabs. Specific examples of the cleansing products include wet tissues, cosmetic cotton, breast milk pads, wiping sheets, sweat absorption sheets (for face, side, neck, feet, etc.), antibacterial / antibacterial sheets, antiviral sheets, Anti-allergen sheets, antibacterial deodorizing sheets, and the like. A specific example of the mask is a disposable three-dimensional mask.

(5) Examples of wiper use include wipers, wet wipers, oil strainers, and copier cleaning materials.

(6) Examples of the agricultural / horticultural use include a nursery sheet, a solid sheet, a defrosting sheet, a herbicidal sheet, and a gardening planter. When used for agriculture and horticulture, for example, it can be used to create an anaerobic environment and perform forcing cultivation.

(7) Examples of household materials include packaging materials, cleaning products, bags, foods, household goods, kitchenware, sports equipment, beauty materials, and the like. Specific examples of the cleaning article include a wiper, a chemical cloth, and a scrubber. A specific example of the bag is a desiccant bag. Specific examples of the food include tea bags, coffee bags, food bags, freshness maintaining materials, food-absorbing sheets, carbonic acid injection agents, food additives, and the like. Specific examples of the household goods include bathing agents, eye masks, cooling sheets, warm sheets, neck scarves, gloves, deodorant 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 specific example of the sports equipment is a fatigue recovery material. Beauty materials include face masks, puffs, beauty packs, beauty gloves, and the like.

(8) Examples of industrial materials include industrial materials, electrical materials, batteries, product materials, OA equipment, AV equipment, rolls, equipment members, and the like.

(9) Examples of experimental materials include anaerobic environment forming materials, anesthetic agents, insect attractants, and the like.

The nonwoven fabric sheet of the present embodiment can be suitably used particularly for applications such as cleaning sheets, living material sheets, beauty sheets, and medical and hygiene sheets such as gauze. Moreover, the same nonwoven fabric sheet can be used in various fields and applications without being limited to the above classification.

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

(Evaluation test)
The nonwoven fabric sheet of the Example and the comparative example was manufactured as follows, and performance was evaluated.

<Evaluation items and test methods>
I. Water retention When water is contained in a nonwoven fabric sheet, the nonwoven fabric sheet has a higher ability to retain the contained water (water retention), and the liquid containing the alkaline component is applied to the object to be cleaned for a longer time. Is considered possible. The water retention can be determined by, for example, the amount of water that can be taken into the nonwoven fabric sheet, the length of time that the taken-in water can be kept inside, and the like. it can.

Here, water retention was evaluated according to the following procedure. First, a predetermined amount (2 ml) of water is contained in each of the nonwoven fabric sheets (5 cm squares) in the examples and comparative examples, and then lightly squeezed to visually observe the amount of water that overflows when the nonwoven fabric sheet cannot be retained. Confirmed by Further, the non-woven sheet after being squeezed lightly was placed on the surface to be cleaned (the surface of a tile having a length and width of 15 cm square) and left for a predetermined time (1 minute). During this time, the surface to be cleaned was tilted with respect to the horizontal, and the presence or absence of water (liquid dripping) overflowing from the nonwoven fabric sheet and dripping was confirmed.

It was evaluated that the smaller the amount of overflowing water, the better the water retention.

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

II. Performance related to dirt removal When the surface to be cleaned is wiped with a nonwoven sheet, the number of wipes until the dirt is removed is less, and the smaller the amount of force that needs to be applied to remove the dirt, the more dirty the nonwoven sheet. It is thought that the performance to drop is high.

Here, a wiping operation of wiping the surface to be cleaned with a nonwoven sheet soaked with water was performed, and the state of dirt removal was visually confirmed. When the dirt was not removed, the wiping operation was repeated with almost the same force as the previous time. The performance of removing dirt was evaluated by the number of wiping operations until the dirt was removed.

Specifically, assuming oil stains adhering to the wall of the kitchen, 1 ml of cooking oil was sprayed and adhered to the surface of a 15 cm square tile in advance in a mist, and a constant temperature of 23 ° C. and 50% RH. It was allowed to stand for 24 hours under constant humidity conditions to solidify. Hereinafter, the edible oil thus solidified is referred to as “oil stain”.

Using the surface of the tile to which this oil stain was attached as the surface to be cleaned, the nonwoven fabric sheet was placed on the surface to be cleaned and left for a predetermined time (1 minute) in accordance with the same procedure as in the water retention test described above. . Subsequently, the wiping operation | movement which wipes the surface of the tile in which the nonwoven fabric sheet was mounted with the nonwoven fabric sheet mounted on the surface was performed. The wiping operation was repeated up to 10 times the maximum until the oil stain was removed.

It was evaluated that the smaller the number of wiping operations until the dirt was removed, the higher the performance related to dirt removal was.

III. Sticking property As one method of using a nonwoven fabric sheet, there is a method in which a nonwoven fabric sheet containing water is left in contact with the surface to be cleaned and a wiping operation is performed after a certain amount of time has elapsed. According to this method, it becomes possible to concentrate and apply the liquid containing an alkaline component to the part of the surface to be cleaned which the nonwoven fabric sheet contacts. According to this, the dirt adhering to the surface to be cleaned can be lifted, and it is considered that the cleaning efficiency is high.

By the way, the surface to be cleaned is not necessarily horizontal, and is not necessarily flat but may be curved or include corners or irregularities. In order to obtain the above-described effects, the nonwoven fabric sheet can be deformed along the shape of the surface to be cleaned and contacted with the surface to be cleaned, and the state can be maintained for a certain period of time. , Sticking property is required.

Here, the following two points were visually confirmed as stickiness.
(1) In the water retention evaluation test described above, the surface to be cleaned (the surface of the tile) was tilted with respect to the horizontal when the presence or absence of liquid dripping was confirmed. Whether you can stay without slipping or peeling.
(2) As an example, a sink (a sink) is assumed to be a clean object, and a non-woven sheet that is quickly submerged in water is adhered to the corner portion (clean target surface) of the sink along its shape. Affixed and left for a predetermined time (1 minute). At this time, whether or not the non-woven sheet can be maintained as it is without being peeled off from the surface to be cleaned.

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

IV. Colorability: Color change, clarity of color change, and pigment spillability When water is included in a nonwoven sheet containing a functional substance such as powder that exhibits alkalinity when contacted with water and a pH indicator (pigment) The hydrogen ion concentration (pH) in water changes due to the reaction of the functional substance. The pH indicator (pigment) blended in the sheet reacts and changes color or changes color accordingly, and the color of the sheet changes. The color corresponding to the pH and the clarity of the color change may vary depending on the type and amount of the pH indicator (pigment). Further, if the pH indicator (pigment) does not stay in the sheet due to water and flows out of the sheet, color transfer occurs in water, and the color of the sheet becomes light, and the color change may not be clear.

Here, as an index of the color developability of the sheet, a test was performed using a sheet forming raw material in which a pH indicator (pigment) was fixed to cellulose fiber as a carrier instead of the sheet. As the pH indicator, a plurality of pH indicators changing from acidic to weakly alkaline were tested. Specifically, according to the following procedure, the colorability (color change, clarity of color change, and color outflow) of the sheet-formed raw material was visually confirmed.
(1) The dye-coated cellulose fibers 2 and 3 obtained in the experimental examples to be described later each contain 5 times (mass basis) of a pH adjuster (acidic, neutral, alkaline).
As an acidic pH adjuster, 0.1 N sulfuric acid (pH 1.4) was used. As a neutral pH adjuster, 1M phosphate buffer (pH 7.0) was used. As an alkaline pH adjuster, 0.1% Ca (OH) ₂ (pH 2.0) was used.
(2) The color change of the cellulose fibers 2 and 3 by the pH adjuster, the clarity of the color change, and the outflow of the dye into the liquid were visually confirmed.
Thereby, it was grasped | ascertained what kind of color a cellulose fiber responds to pH about each pH indicator. The clearer the color change, the more preferable it is because the user can easily recognize the pH change when used when applied to the nonwoven sheet. Further, the smaller the outflow of the dye, the better the color change of the sheet is clear, the pH change is easily recognized, and the influence of the material outflow on the environment is small. Regarding the outflow of the dye, the effect of the presence or absence of the binder in the dye solution was confirmed.

V. Sheet Colorability: Color Change and Dye Discharge Efficacy The following test was conducted on the nonwoven 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, and 5 times the weight of the sheet was included in water. At this time, the color and pH of the sheet before and after adding water (dry state), immediately, 15 minutes, and 60 minutes later were confirmed.

(Dye efflux)
As one indicator of dye efflux, a white plastic sheet was wiped with a colored sheet, and color transfer was visually confirmed. Here, “color transfer” means that a coloring matter that is a coloring component of a sheet elutes out of the sheet and moves to a plastic sheet. The smaller the degree of color transfer, the lower the dye outflow and the better. More preferably, the color transfer cannot be confirmed.

[Example 1]
<Manufacture of nonwoven 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 each defibrated using a swirling jet airflow defibrating device to obtain respective defibrating shortcut fibers.

Next, the rayon fiber in the form of a defibration shortcut fiber and the heat-fusible composite fiber in the form of a defibration shortcut fiber are uniformly mixed at a ratio (mass ratio) of 60/40 by an air flow, and rayon / ( PET / PE) fiber mixture was obtained.

Sodium hydrogen carbonate (average particle size 100 μm) and PE powder (average particle size 400 μm) were mixed at a ratio (mass ratio) of 80/20 to obtain a particle mixture of sodium hydrogen carbonate / PE powder.

Then, using the web forming apparatus 1 shown in FIG. 4 on the carrier sheet, a sheet in which an airlaid web was 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 formed on the air-permeable endless belt 20 mounted on the conveyor 10 by the first carrier sheet supply means 40. The first carrier sheet 41 composed of ² / s) was fed out.

While sucking the air-permeable endless belt 20 by the suction box 60, the PE powder is spread on the first carrier sheet 41 so as to be 5 g / m ^2, and the air flow is supplied from the fiber mixture supply means 30 onto the PE powder. Along with this, the fiber mixture was dropped and deposited. At that time, the fiber mixture was supplied so that the basis weight per air laid web portion was 100 g / m ² .

Next, a particle mixture of sodium hydrogen carbonate / PE powder was sprayed on the airlaid web to a concentration of 50 g / m ² and deposited. A second carrier sheet made of rayon spunlace nonwoven fabric (basis weight 27 g / m ² , air permeability 292 cm ³ / cm ² / s) was laminated thereon to obtain an airlaid web-containing laminated sheet.

The obtained laminated sheet was passed through a hot air circulating conveyor oven type box type dryer and subjected to hot air treatment at 140 ° C. to obtain a nonwoven fabric sheet having a basis weight of 209 g / m ² .

[Example 2]
<Manufacture of nonwoven 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 part melting point 130 ° C.) is unwound using a swirling jet airflow defibrating device. After fiber processing, a defibration shortcut fiber was obtained.

Next, the pulp / (PET / PE) fiber is obtained by uniformly mixing the softwood chemical pulp and the heat-fusible composite fiber in the form of a defibrated shortcut fiber at a ratio (mass ratio) of 60/40 by an air flow. A mixture was obtained.

Next, using the web forming apparatus 1 shown in FIG. 4 on the carrier sheet, a sheet in which an airlaid web was formed using a fiber mixture and sodium hydrogen carbonate (average particle size 100 μm) was obtained.

While sucking the air-permeable endless belt 20 by the suction box 60, the PE powder is spread on the first carrier sheet 41 so as to be 5 g / m ^2, and the air flow is supplied from the fiber mixture supply means 30 onto the PE powder. At the same time, the fiber mixture and sodium hydrogen carbonate were dropped and deposited while mixing at a ratio (mass ratio) of 100/15. At that time, the fiber mixture and sodium bicarbonate were supplied so that the basis weight per air laid web portion was 115 g / m ² .

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

The obtained laminated sheet was passed through a hot air circulating conveyor oven type box type dryer and subjected to hot air treatment at 140 ° C. to obtain a nonwoven fabric sheet having a basis weight of 179 g / m ² .

[Example 3]
<Manufacture of nonwoven sheet>
Instead of rayon spunlace nonwoven fabric, a tissue made of wood pulp (basis weight 14 g / m ² ) is laminated as a ^second carrier sheet, and a hot melt adhesive (ethylene / vinyl acetate copolymer) is laminated thereon. ) 5 g / m ² coated film (PE, basis weight 26 g / m ² ) is the same as in Example 1 except that the surface of the film coated with the hot melt adhesive is laminated so as to face the tissue. A sheet was obtained. The basis weight was about 227 g / m ² .

[Example 4]
<Preparation of dye solution>
50 g of 2% bromothymol blue solution (solvent is ethanol), 10 g of 50% benzalkonium chloride aqueous solution, and 40 g of polyvinyl butyral were dissolved in isopropanol and diluted with isopropanol to a total of 500 g (mass / Mass basis). A mixed solution was prepared by mixing until the polyvinyl butyral was completely dissolved, and a dye solution C1 was obtained.

<Application of dye solution to carrier>
While stirring 50 g of powdered cellulose fibers (fiber length: 0.2 mm) with a mixer, 25 g of the dye solution C1 was added and stirred until the fibers and the dye solution were uniformly mixed. Subsequently, it was made to dry at 105 degreeC for 2 hours conditions with the dryer, the solvent was removed, and the powder-form pigment coating cellulose fiber 1 (fiber length 0.2mm) was obtained.

<Manufacture of nonwoven sheet>
Instead of the sodium hydrogen carbonate / PE powder particle mixture, sodium hydrogen carbonate (average particle size 100 μm), PE powder (average particle size 400 μm) and dye-coated cellulose fiber 1 in a ratio (mass ratio) of 70/25/15 The sheet was obtained in the same manner as in Example 1 except that a mixture of sodium hydrogen carbonate / PE powder / dye-coated cellulose fiber 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 size 400 μm) was sprayed on the air laid web so as to be 5 g / m ² instead of the particle mixture. The basis weight was about 164 g / m ² .

[Comparative Example 2]
Instead of a fiber mixture of rayon / (PET / PE), a core-sheath type heat-sealable composite fiber in the form of a defibration shortcut fiber (PET / PE composite core-sheath fiber, fineness 2.2 dtex, fiber length 5 mm, sheath An airlaid web-containing sheet was obtained in the same manner as in Example 1 except that the partial melting point was 130 ° C.

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

(Table 1) pH indicator

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

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

A powdery dye-coated cellulose fiber 3 (fiber length 0.2 mm) was obtained in the same manner except that the dye solution C3 was used instead of the dye solution C2.

(Test results)
Table 3 shows the evaluation test I.I. To III. The results are shown. Table 4 shows the evaluation test IV. The results are shown. Table 5 shows the evaluation test The results are shown.

(Table 3) Evaluation test To III. Result of

(Table 4) Evaluation test IV. Result of

(Table 5) Evaluation test Result of

The test results are indicated by symbols ◯, Δ, and × in order from the one with good evaluation. The specific evaluation contents are as follows.
I. Water retention ○: Water did not overflow when lightly squeezed, and the nonwoven fabric sheet could retain the contained water. Moreover, when the nonwoven fabric sheet was placed on the surface to be cleaned and left to stand, no liquid dripping phenomenon was observed.
X: The water overflowed before repelling water and squeezing lightly, and the nonwoven fabric sheet could not hold the contained water.
II. Dirt removal ○: The oil stain could be easily wiped off by one wiping operation.
(Triangle | delta): The oil stain was able to be wiped off by performing wiping off operation several times.
X: Even if the wiping operation was repeated 10 times, oil stains could not be wiped off III. Stickability ○: The nonwoven fabric sheet did not peel from the surface to be cleaned.
X: The nonwoven fabric sheet peeled off from the surface to be cleaned.
IV. Color development ○: The color change was large and clear.
Δ: The color change was visible.
X: The color change was small and unclear.

As described above, the nonwoven fabric sheet of the present embodiment was able to sufficiently retain water containing an alkaline component. Moreover, the nonwoven fabric sheet of this Embodiment was able to wipe off easily with oil stains floating. Furthermore, the nonwoven fabric sheet of this Embodiment did not peel from the surface to be cleaned during application to the surface to be cleaned.

In other words, the nonwoven fabric sheet of the present embodiment can be deformed along the shape of the surface to be cleaned while maintaining the water containing the alkaline component, and can maintain the shape, so the water containing the alkaline component Can be effectively applied to the surface to be cleaned.

In addition, from Experimental Examples 1 to 8, it was found that the color of cellulose fibers carrying a pH indicator (dye) changes in response to pH change. It has been found that by appropriately selecting the pH indicator (pigment) to be used, it is possible to achieve a configuration in which a color change occurs in a desired pH region. It was also found that a clear color change can be obtained by appropriately selecting the pH indicator (dye) to be used. Further, at this time, it was found that the tendency of the dye to flow out of the obtained carrier can be reduced by blending the binder into the dye solution for fixing the pH indicator (dye) to the carrier. This is presumably because the pH indicator (dye) and the carrier were more firmly fixed by the binder.

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

Therefore, in the nonwoven fabric sheet of the present embodiment, by using a carrier carrying a pH indicator (pigment) as a constituent element 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 nonwoven fabric sheet exhibits a pH in a desired pH region and that the nonwoven sheet no longer exhibits a pH in the desired pH region by a color change of the nonwoven fabric sheet. it can. Therefore, the user can use the non-woven sheet while the non-woven sheet is exhibiting a pH in a desired pH range (that is, a time suitable for use), and can easily end use of the non-woven sheet. Can be judged.

DESCRIPTION OF SYMBOLS 1 Web formation apparatus 30 Fiber mixture supply means 41 1st carrier sheet 51 2nd 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 Functional layer containing layer 200 Acidic layer 300 Water-permeable or water-absorbing 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 (dye )
W Airlaid Web

Claims

A nonwoven sheet comprising a web layer formed by an airlaid method,
The nonwoven sheet includes a powder exhibiting alkalinity when contacted with moisture,
The web layer is a nonwoven fabric sheet mainly composed of a water-absorbing material.
The nonwoven fabric sheet according to claim 1, wherein the powder is contained in the web layer.
The nonwoven fabric sheet according to claim 2, wherein the powder is unevenly distributed on one surface 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 layers 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 water-absorbing fibers.
The nonwoven fabric sheet according to any one of claims 1 to 6, wherein the nonwoven fabric sheet includes a particulate heat-fusible resin having a particle diameter of 1 µm to 1000 m.
The nonwoven fabric sheet according to any one of claims 1 to 7, wherein the web layer includes 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 nonwoven fabric sheet according to any one of claims 1 to 8, wherein the nonwoven fabric sheet includes a water-permeable or water-absorbent sheet adjacent to the web layer.
The nonwoven fabric sheet according to claim 5, wherein the nonwoven fabric sheet includes a water-permeable or water-absorbent sheet adjacent to the powder disposed 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 said nonwoven fabric sheet is a nonwoven fabric sheet as described in any one of Claim 1 to 11 which further contains the acidic layer containing the powder which exhibits an acidity when it contacts with a water | moisture content.
The nonwoven sheet contains a pH indicator and a carrier in the same layer as the powder,
The nonwoven fabric sheet according to any one of claims 1 to 12, wherein the pH indicator is fixed to the carrier with a quaternary ammonium salt.
The nonwoven fabric sheet according to claim 13, further comprising a binder, wherein the pH indicator is fixed to the carrier by the quaternary ammonium salt and the binder.