JP4249593B2 - Absorbent articles - Google Patents

Description

  The present invention can suppress the generation of harmful gases and the like when incinerating the absorbent article having a body fluid absorbing layer such as disposable diapers and sanitary napkins, and as a sanitary material. The present invention relates to an easily combustible absorbent article that can be suitably used.

Absorbent articles with an absorbent layer are designed to efficiently absorb body fluids such as urine, blood, menstrual blood, sweat, and disposable diapers, sanitary napkins, incontinence pads, cage sheets, breast milk pads, Used for medical underpads, surgical underpads, pet seats, etc. Since these absorbent articles are intended to absorb the body fluid, the incineration method is generally used as a disposal method after use due to hygiene problems.
In recent years, the amount of incineration of garbage itself has been decreasing due to the enforcement of the Container Recycling Law, etc., and the proportion of absorbent articles after use has increased in total garbage, and diapers for elderly people have become popular. As a result, the proportion of absorbent article waste in all incineration waste tends to increase further. In addition, the proportion of in-house incineration is increasing as a treatment method for used absorbent articles in nursing homes and hospitals, but incineration in such places is currently more absorbent than ordinary trash. It is.
On the other hand, it has been pointed out that dioxins, which are harmful substances generated from incinerators, are caused by incomplete combustion of substances containing carbon and salt of chlorine compounds at low temperatures. In particular, the waste of disposable diapers contains a large amount of water that has a large latent heat of vaporization and contains a large amount of moisture that has a large latent heat of vaporization and contains the carbon component of the disposable diaper and the salt of the chlorine compound contained in the body fluid. there were. Therefore, incineration of used waste of absorbent articles has a problem that dioxins are generated due to incomplete combustion.

In order to solve this problem, a method of incineration in the presence of a specific polyvalent metal compound such as aluminum, magnesium, calcium or the like has been proposed (for example, Patent Document 1). This method can suppress the melting and solidification of the superabsorbent resin, which causes damage to the incinerator, and can prevent adhesion to the incinerator, but it promotes complete combustion and suppresses the generation of toxic gases. Cannot be expected. An absorbent article containing an iron-based combustion accelerator has been proposed (for example, Patent Document 2). However, since the iron-based combustion accelerator is colored from black to yellow due to the crystal system, if the iron-based combustion accelerator is contained in the synthetic resin, the resin composition is colored and the absorbent article is also colored. This is a problem that the color of body fluid cannot be accurately determined. For example, when a minute amount of blood is mixed in excrement or the like, there is a problem that it cannot be visually confirmed. Therefore, there is a restriction that it cannot be used as a sanitary material on a site that directly absorbs body fluid.
JP 2000-136314 A JP 2002-11048 A

  The object of the present invention is suitable as a sanitary material that solves the problems of the above-described technology and can suppress the generation of harmful gases even when incinerated in the presence of a chlorine source and a large amount of water without coloring. Is to provide an absorbent article.

As a result of intensive studies in view of the above problems, the present inventors have found that the above-mentioned problems can be achieved without coloring the absorbent article by containing a specific amount of an aluminum-based combustion accelerator in the absorbent article. The present invention has been reached.
That is, the invention claimed in the present application is as follows.
(1) An absorbent article provided with a body fluid absorbing layer, the body fluid absorbing layer containing 0.01 to 5% by weight of an aluminum-based combustion accelerator having a particle size of 0.005 to 0.05 μm. An absorbent article characterized by the above.
(2) An absorbent article provided with a body fluid absorbing layer, a liquid impermeable sheet and / or a liquid permeable sheet, and any member constituting the absorbent article has a particle size of 0.005 to 0.005. An absorbent article containing 0.01 to 5% by weight of an aluminum-based combustion accelerator of 0.05 μm.

  Since the absorbent article of the present invention contains a specific amount of an aluminum-based combustion accelerator, even if the used absorbent article containing a body fluid that becomes a chlorine source is incinerated, complete combustion of waste is promoted. Incineration ash at the time of incineration can be reduced, and complete combustion is promoted by the catalytic effect of the aluminum-based combustion accelerator during incineration at low temperature or low oxygen, generation of carbon monoxide due to incomplete combustion and dioxin precursor Generation can be suppressed. Moreover, since coloring of an absorbent article can be prevented and the color of a bodily fluid can be discriminate | determined clearly, it is especially useful as a sanitary material.

The absorbent article in the present invention is not particularly limited in its structure as long as it is an absorbent article provided with a body fluid absorption layer. For example, in addition to an absorbent article consisting only of a body fluid absorption layer, the front and back of the body fluid absorption layer An absorbent article in which a liquid-impermeable sheet and a liquid-permeable sheet are laminated to each other, and an absorbent article in which any one of a liquid-impermeable sheet or a liquid-permeable sheet is laminated on a body fluid absorbing layer.
The body fluid absorbing layer used in the present invention is not particularly limited as long as it can absorb body fluids such as urine, blood, menstrual blood, and sweat, and pulp, water absorbent resin, or the like is used. As the pulp, spreaded pulp is preferably used, and usually a sheet-like one is used. As the water-absorbing resin, a resin capable of absorbing water several tens to several thousand times its own weight is used.
Examples of the absorbent resin include a crosslinked polyacrylic acid partial neutralized product, a starch-acrylonitrile copolymer partial hydrolyzate, a starch-acrylic acid graft copolymer, and a vinyl acetate-acrylic ester copolymer hydrolyzed. Degradation product, copolymerized crosslinked product of 2-acrylamido-2-methylpropanesulfonic acid and acrylic acid, crosslinked product of cationic monomer, crosslinked isobutylene-maleic anhydride copolymer, crosslinked polyethylene oxide, crosslinked polyvinyl alcohol, carboxy A methylcellulose crosslinked body, an alginic acid crosslinked body, a starch crosslinked body, a polyamino acid crosslinked body, etc. can be used.
If necessary, an inorganic compound such as colloidal silica, white carbon, ultrafine silica, and titanium oxide powder, and an organic compound such as a chelating agent may be added to the water absorbent resin. Furthermore, you may mix an oxidizing agent, antioxidant, a reducing agent, a ultraviolet absorber, an antibacterial agent, a disinfectant, a fungicide, a fertilizer, a fragrance | flavor, a deodorizing agent, a pigment, etc.
Moreover, you may use as a composite sheet which used the pulp sheet and the water absorbing resin together. In forming a sheet, a method of spreading pulp and / or water-absorbing resin on the sheet and wrapping the sheet with the sheet, a method of fixing to the sheet with a hot melt resin, an adhesive, or the like can be used. Moreover, it is also possible to set it as the structure which laminated | stacked the pulp sheet and the water absorbing resin layer in the multilayer.

The liquid-impermeable sheet used in the present invention is referred to as a back sheet, and has a function of preventing body fluid absorbed by the body fluid absorbing layer from leaking outside. The liquid-impermeable sheet is not particularly limited as long as it does not allow liquid to permeate. For example, a thermoplastic resin film, a film and a nonwoven fabric bonded together, and the like can be prevented from being worn. From the point of view, a porous material that prevents permeation of body fluid but allows water vapor to permeate is preferably used.
The liquid-permeable sheet used in the present invention is also referred to as a top sheet. For example, the liquid-permeable sheet is used by being laminated on the upper part of the body fluid absorbing layer in order to prevent the body fluid absorbing layer from directly touching the skin. The top sheet is made of a material having excellent liquid permeability, such as a porous woven fabric, a nonwoven fabric, a porous film, etc., which can quickly permeate body fluid and lead to the body fluid absorbing layer. Of these, the use of a nonwoven fabric is particularly preferred from the viewpoint of soft texture and industrial productivity. Further, a water permeable agent such as a surfactant may be added to the top sheet in order to increase the permeability of body fluid. Furthermore, when using it for the application which touches skin directly, the thing with the smooth surface which has the touch close to underwear is preferable, and the body fluid which absorbed is hard to remain on the surface, and uses the sheet | seat which consists of hydrophobic materials in order to obtain a dry feeling Is preferred.

The top sheet may contain an anti-inflammatory agent, a moisturizing agent, an antibacterial agent, an additive having a deodorizing function and a deodorizing function as necessary. Further, in order to control the absorption of body fluid on the top sheet, the top sheet may be subjected to perforation processing, uneven processing, and streak groove processing. Further, for the purpose of preventing the flow of body fluid in the lateral direction, a hydrophobic compound such as a silicon-based compound or a paraffin-based compound can be applied in a streak pattern on the top sheet.
Moreover, an absorbent article can be made into the structure without a top sheet or a back sheet as needed. That is, one member may have two or more functions at the same time. For example, the body fluid absorbing layer can have a liquid diffusion function. Moreover, it is good also as a filmless structure which combined the back sheet | seat and bodily fluid absorption.

The material for forming the back sheet or the top sheet is not particularly limited. For example, polypropylene, polyethylene, polyethylene-polypropylene random copolymer, polyester and its copolymer, polyamide and its copolymer, polyvinyl chloride, polychlorinated Thermoplastic resins such as vinylidene, polyacrylonitrile and copolymers thereof, cupraammonium rayon, viscose rayon, cellulose fiber using N-methylmorpholine oxide as a solvent, regenerated fiber such as acetate fiber, and natural fiber such as cotton, wool, and silk Etc. can be used.
Moreover, you may use the thermoplastic resin which has biodegradability. Examples of these are aliphatic polyesters or aliphatic polyester amides. Examples of aliphatic polyesters include polyglycosides, poly (α-hydroxycarboxylic acids) such as polylactic acid, and poly-ε-caprolactone. Examples of aliphatic polyester amides include ε-caprolactone and ε-caprolactam. Copolymers of lactones and lactams such as polymers are listed.
As the form of the sheet, it is used in the state of a water-permeable porous sheet such as nonwoven fabric, hydrophilized polyethylene, and polypropylene.

The absorbent article in the present invention is obtained by laminating the above-described body fluid absorbing layer, or a liquid impermeable sheet and / or a liquid permeable sheet on the body fluid absorbing layer. The aluminum-based combustion accelerator in one member is 0.01 to 5% by weight, preferably 0.02 to 5% by weight, particularly preferably 0.03 to 3.0% by weight, based on the total weight of the absorbent article. % Content is required.
The aluminum-based combustion accelerator used in the present invention is an aluminum compound exhibiting catalytic activity for combustion, and specifically, oxides such as alumina and composite oxides such as silica-alumina and titania-alumina are used. . In order to further improve the activity of these oxides, metals or metal oxides such as vanadium, molybdenum, tungsten, manganese, cobalt, copper, iron, platinum, and palladium may be added as active components.

If the content of the aluminum-based combustion accelerator is less than 0.01% by weight, a sufficient combustion promotion effect cannot be obtained, and if it exceeds 5% by weight, the flammability of the material itself becomes too high. Arise. In particular, when an aluminum-based combustion accelerator is used by being kneaded into a resin, if it exceeds 5% by weight, physical and mechanical properties are deteriorated and weather resistance is deteriorated.
The aluminum-based combustion accelerator is preferably fine particles having a particle size in the range of 0.005 to 1 μm. From the viewpoint of improving the catalytic activity, fine particles having a large specific surface area are preferred. When the particle size is less than 0.005 μm, the catalytic effect becomes high, but the handling becomes complicated, and industrial and economical practicality is lowered. On the other hand, if the particle size exceeds 1 μm, the catalytic activity for combustion may be reduced.
Furthermore, the aluminum-based combustion accelerator can be used by treating the surface of the aluminum-based combustion accelerator particles with various surface treatment agents for the purpose of improving the dispersibility in the synthetic resin.

As a method for producing a body fluid absorbing layer containing an aluminum-based combustion accelerator, a method using a water-absorbing resin containing an aluminum-based combustion accelerator, or directly when producing a body fluid-absorbing layer from a water-absorbing resin and / or pulp, is used. A method of mixing an aluminum-based combustion accelerator, an aluminum-based combustion accelerator is mixed with a dispersant and a binder to obtain an additive liquid, and the additive liquid is sprayed, coated or dipped on the surface of the member to obtain an aluminum-based combustion accelerator. The method of attaching is mentioned.
In addition, as a method of adding an aluminum-based combustion accelerator to a liquid-impermeable sheet or a liquid-permeable sheet, for example, a method of adding an aluminum-based combustion accelerator when manufacturing a material constituting the sheet was manufactured. Examples thereof include a method of fixing and applying an aluminum-based combustion accelerator to a sheet.

In the method of adding an aluminum-based combustion accelerator when producing a material, when forming a sheet by adding to a thermoplastic resin, the aluminum-based combustion accelerator particles are mixed with a mixing roll, a Banbury mixer, a kneader, biaxial kneading. It can be kneaded using an extruder or the like to form a nonwoven fabric. It can also be formed into a film by the same method. Further, a porous film-like sheet can be produced by adding a foaming agent and foaming, or adding a nucleating agent and opening by stretching. Further, it can be produced by preparing a master batch of high concentration in advance, blending it with a virgin chip in an extruder for fiberization and film formation, preparing it to a predetermined concentration, fiberizing and filming. At the time of kneading, various additives such as generally known antioxidants, weathering agents, colorant lubricants and antiblocking agents, and organic and inorganic fillers may be blended as necessary. In the case of a non-thermoplastic resin, it is made into a fiber and film from a resin solution dissolved in a solvent, and can be produced by adding and dispersing an aluminum-based combustion accelerator in this solution.
In the method of fixing and applying the aluminum-based combustion accelerator after forming into a sheet, the aluminum-based combustion accelerator is mixed with a dispersant and a binder to form an additive liquid, and the additive liquid is sprayed, coated, or dipped on the surface of the member. Thus, a method of attaching an aluminum-based combustion accelerator can be employed.

Absorbent articles containing aluminum-based combustion accelerators contain calcium hydroxide to react with hydrogen chloride and convert it into calcium chloride, which is difficult to thermally decompose, in order to further reduce the hydrogen chloride generated during incineration. Further, calcium oxide or the like may be contained. The method of inclusion may be added simultaneously or separately when the aluminum-based combustion accelerator is applied.
Since the absorbent article of the present invention contains an aluminum-based combustion accelerator, it is possible to prevent a reduction in combustion efficiency when incinerated as waste after use, and to achieve complete combustion of the waste. The production of harmful substances such as dioxins can be suppressed.
Examples of this absorbent article include, for example, children's disposable diapers, adult disposable diapers, sanitary napkins, tampons, panty liners, sanitary sheets, incontinence pads, cage sheets, breast milk pads, medical underpads, and surgical use. Examples include underpads, medical blood absorbers, and pet sheets. Moreover, it is not limited also to the shape of an absorbent article, For example, in the case of a paper diaper, a pants type, a tape type, etc. can be mentioned as an example.

Hereinafter, the present invention will be described in detail with reference to examples. In addition, the combustion characteristic of the absorbent article was evaluated by the following method.
The sample was heated at a rate of 10 ° C./min in air at 300 ml / min and burned, and the weight change at this time was measured with a thermogravimetric analyzer (manufactured by Seiko Denshi Kogyo Co., Ltd.). The residual weight ratio (%) converted per combustible component at the time when the process was completed.
[Example 1 and Comparative Example 1]
A 1.5% polyvinyl alcohol aqueous solution in which an aluminum oxide-based combustion accelerator having an average particle size of 0.05 μm is dispersed in a non-woven fabric (manufactured by Asahi Kasei Co., Ltd., spunbonded non-woven fabric: ELTAS P03020) is burned with aluminum oxide based on the weight of the non-woven fabric. Coating was performed so that the amount of the agent was 0.03% (Example 1). At this time, coloring of the nonwoven fabric due to the application of the aluminum oxide-based combustion agent was not recognized. In addition, only the nonwoven fabric was used as the comparative example 1.
Combustion characteristics were evaluated by burning these nonwoven fabrics. The residual weight percentage of Example 1 to which the aluminum oxide-based combustion accelerator was applied was 97.8%, whereas in Comparative Example 1 to which no aluminum oxide-based combustion accelerator was added, the residual weight ratio was 81.5%. Yes, the combustion promotion effect of the aluminum oxide-based combustion accelerator of the nonwoven fabric obtained in Example 1 was confirmed.

[Examples 2 to 5, Comparative Example 2 and Reference Example 1 ]
Several master batches were prepared by adding 10 wt% of particulate aluminum combustion accelerators having different particle sizes shown in Table 1 to polypropylene having an MFR of 38 measured according to JIS K7210. This master batch and polypropylene with MFR = 38 were blended by adjusting so that the final aluminum-based combustion accelerator addition amount was the addition amount shown in Table 1, and the nozzle diameter was 0.35 mm, the number of nozzles was 3000 / Using a two-layer laminated spunbond manufacturing machine with m, melt spinning at a discharge rate of 1.7 Kg / min · m · layer, adjusting the fineness by adjusting the flame credit high-speed air flow, and adjusting the dispersion / opening device I got each web. Each obtained web was passed between a flat roll and an embossing roll, heat and pressure were adjusted with temperature and linear pressure, and the fibers were bonded together to obtain a spunbonded nonwoven fabric containing a particulate aluminum combustion accelerator.
The obtained nonwoven fabric was burned to evaluate the combustion characteristics, and the results were shown. The remaining weight ratio of the nonwoven fabrics of Examples 2 to 5 to which the aluminum oxide-based combustion accelerator was added was 97.3% to 98.7. % Of the nonwoven fabric of Comparative Example 2 in which the addition amount of the aluminum oxide-based combustion accelerator is 0.005% outside the scope of the present invention , the residual weight ratio is 85.6%. The combustion promotion effect of the aluminum oxide combustion promoter in the nonwoven fabric of the invention was confirmed.

According to the absorbent article of the present invention, since it contains an aluminum-based combustion accelerator, even if the used absorbent article contains moisture or a body fluid chlorine source, complete combustion of these can be achieved at the time of combustion incineration. Therefore, the generation of carbon monoxide and dioxin precursors due to incomplete combustion can be suppressed, and the color of body fluid can be clearly distinguished without coloring the absorbent article. Sanitary materials such as disposable diapers, sanitary napkins, tampons, panty liners, sanitary sheets, incontinence pads, cage sheets, breast milk pads, medical underpads, surgical underpads, medical blood absorbers, pet sheets, etc. Is extremely useful.

Claims (2)

An absorbent article provided with a body fluid absorbing layer, wherein the body fluid absorbing layer contains 0.01 to 5% by weight of an aluminum-based combustion accelerator having a particle size of 0.005 to 0.05 μm. Absorbent article. An absorbent article comprising a body fluid absorbing layer, a liquid impermeable sheet and / or a liquid permeable sheet, wherein any member constituting the absorbent article has a particle size of 0.005 to 0.05. An absorbent article containing 0.01 to 5% by weight of an aluminum-based combustion accelerator of μm.