JP2000262559A - Sanitary goods - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide sanitary goods with biodegradability and excellent water- absorbency. SOLUTION: Snitary goods with a laminated structure comprising a top sheet layer, an absorbing core layer and a back sheet layer is provided and the above described absorbing core layer comprises a crosslinked polyamino acid resin and the above described top sheet layer and/or the above described back sheet layer comprise a biodegradable polymer. Water absorbency wherein amt. of equilibrium swelling absorption of physiological saline is 30-200-fold per unit wt. of the polymer is provided. In addition, water absorbency wherein when physiological saline is absorbed for 1 min, amt. of absorption of physiological saline is 20-150-fold per unit wt. of the polymer is provided. Furthermore, water absorbency wherein amt. of absorption of physiological saline under loading of 20 g/cm2 is 0.15-150-fold per unit wt. of the polymer is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

2. Description of the Related Art [Technical background of disposable hygiene articles] Disposable hygiene articles are articles designed to efficiently absorb bodily fluids such as urine, blood, menstrual blood, sweat, etc., such as disposable diapers, sanitary napkins, It is used for incontinence pads, breast milk pads, medical underpads, surgical underpads, pet seats and the like. Conventionally, such a sanitary material is mainly composed of a topsheet made of a nonwoven fabric or a porous molded polyethylene film or a polypropylene film material, a backsheet made of polyethylene, and an absorbent core in which a water-absorbing resin is dispersed in pulp. These materials are not biodegradable except for pulp.

[Technical background of disposal of disposable sanitary goods waste] The used waste of the above sanitary materials accounts for several percent of the total waste by weight, but these disposable sanitary materials are degradable. Therefore, disposal after use is a problem. At present, these water-absorbent resins are incinerated at the time of disposal and landfilled.However, in the incinerator method, in addition to damage to furnace materials due to heat generated during incineration, It has been pointed out that it causes global warming and acid rain. On the other hand, it has been pointed out that the cause of the generation of dioxin from incinerators is caused by incomplete combustion of substances containing carbon and chlorine at low temperatures. Particularly, the waste of disposable diapers contains carbon and chloride salts, and has a large latent heat of vaporization and contains a large amount of hardly flammable water, which may lower the temperature of the incinerator. Even though the disposable diaper material itself is not a direct source of dioxin generation, it is composed of organic matter, and its waste contains salt, which temporarily lowers the temperature in the incinerator. It is necessary to review the disposal method. Also, in the landfill method, disposable diaper waste is composed mainly of non-degradable plastic, so there are problems such as its bulky volume and its unstable ground because it does not rot. A major problem is that there is no longer a place suitable for landfill as the center.

[0003] In response to such a problem, proposals have been made to use a part of the constituent materials of the sanitary material as a degradable material. For example, Japanese Patent Publication No. 5-505318 proposes to use a film made of a dioxane-based polymer as a back sheet. However, even if only a part of the constituent materials is decomposed, unless the other materials are decomposed, it will not be a fundamental solution of the disposal treatment, and it is expected that the accumulation of components that do not decompose on the contrary will become a problem.

[Technical background of water-absorbent resin] A water-absorbent resin is a resin capable of absorbing water of several tens to several thousand times its own weight, and is used for sanitary products such as sanitary products, disposable diapers, breast milk pads, disposable rags, and the like. Dressing materials for wound protection, medical supplies such as medical underpads, cataplasms, pet sheets, portable toilets, gel fragrances, gel deodorants, sweat absorbing fibers, disposable warmers and other household items, shampoos, and sets Toiletries such as gels and moisturizers, water retention materials for agriculture and horticulture, life-promoting agents for cut flowers, floral foam (fixing material for cut flowers), nurseries for raising seedlings, hydroponics, vegetation sheets, seed tape, fluid sowing, Agricultural and horticultural products such as agricultural sheets for preventing dew condensation, freshness-retaining materials for food trays, food packaging materials such as drip-absorbent sheets, cooling materials, and transport materials such as water-absorbent sheets for transporting fresh vegetables, Construction materials for dew prevention, sealing materials for civil engineering and construction, anti-sludge agents for shield method, concrete admixtures, civil engineering and building materials such as gaskets and packing, sealing materials for electronic devices such as optical fibers, waterproof materials for communication cables Used in a wide range of fields, including electrical equipment-related materials such as inkjet recording paper, coagulants for sludge, dewatering of gasoline and oils, water treatment agents such as water removers, printing pastes, water-swellable toys, and artificial snow. Have been. In addition, it is expected to be used for sustained-release fertilizers, sustained-release pesticides, sustained-release drugs, and the like by utilizing the sustained-release properties of the chemicals. Further, it is also expected to be used as a humidity control material utilizing its hydrophilicity, and as an antistatic agent utilizing its charge retention.

[Prior art relating to water-absorbing resin] Examples of the water-absorbing resin used in such sanitary materials include, for example, a partially neutralized crosslinked polyacrylic acid (JP-A-55-84).
No. 304, U.S. Pat. No. 4,625,001), a partially hydrolyzed starch-acrylonitrile copolymer (JP-A-46-4).
3995), starch-acrylic acid graft copolymer (JP-A-51-125468), and hydrolyzate of vinyl acetate-acrylate copolymer (JP-A-52-1468).
No. 9), copolymerized crosslinked product of 2-acrylamido-2-methylpropanesulfonic acid and acrylic acid (European Patent 0068)
189), a crosslinked product of a cationic monomer (US Pat.
No. 906717) and a crosslinked isobutylene-maleic anhydride copolymer (US Pat. No. 4,389,513) are known.

[0006] However, these water-absorbent resin compositions are decomposed into cross-linked parts and become water-soluble resins, but the main chain has no decomposability at all, or only a part thereof is decomposed, so that after use, Disposal is a problem. In particular, it has been reported that polyacrylic acid can decompose up to 7-mers, and oligomers of 8-mers or more have no biodegradability.
(JE Glass and G. Swif Ed
s. , "Agricultural & Synthetic
Polymers: Utilization & Bio
degradability ”, American C
chemical Society, Washingto
n, D. C. (1990), M.C. Shimao, H .; S
aimoto, Y .; Taniguchi, N .; Kat
o, C.I. sakazawa: Appl. Enviro
n. Microbiol. , Vol. 46, pp. 60
5 (1983); Matsumura, S .; Ma
eda, S .; yoshikawa, N .; Chikazu
mi: J. Jpn. Oil Chem. Soc. (YU
KAGAKU), Vol. 39, pp. 1245- (1
990), etc. That is, these resins are poorly decomposable and exist semipermanently in water and soil, which is a very serious problem in view of environmental conservation in waste treatment. For example, in the case of disposable resins represented by sanitary materials such as disposable diapers and sanitary articles, recycling the resin requires a great deal of cost, and the amount of incineration is large, so that the burden on the global environment is great. It has also been reported that when buried waste containing cross-linked polyacrylic acid resin, it forms a complex with polyvalent ions such as Ca ²⁺ in soil and forms an insoluble layer (Matsumoto et al., Polymer, Volume 42, August, 1993
Year). However, although such layers are said to have low toxicity per se, they are completely absent in nature,
The effects on the ecosystem of the long-term accumulation of these resins in the soil are unknown and need to be thoroughly investigated, and their use requires a cautious attitude. Similarly, in the case of a nonionic resin, a complex is not formed, but the nondecomposable resin may accumulate in soil due to its nondegradability, and its effect on the natural world is doubtful. Furthermore, these polymerization resins use monomers that are highly toxic to human skin, etc., and many studies have been made to remove them from products after polymerization, but they have been completely excluded. It is difficult. In particular, it is expected to be more difficult in production on an industrial scale.

[Technical background of water-absorbing resin having biodegradability] On the other hand, in recent years, biodegradable polymers have attracted attention as “earth-friendly materials”, and it has been proposed to use this as a water-absorbing resin. ing. Examples of the biodegradable water-absorbing resin used for such applications include, for example, a polyethylene oxide crosslinked product (JP-A-6-15779).
No. 5, etc.), cross-linked polyvinyl alcohol, cross-linked carboxymethyl cellulose (US Pat. No. 4,650,716),
Alginic acid crosslinked products, starch crosslinked products, polyamino acid crosslinked products, and the like are known. Among these, crosslinked polyethylene oxide and crosslinked polyvinyl alcohol can be biodegraded only by special bacteria, so that biodegradability is slow or not decomposed at all under general conditions. Further, when the molecular weight is further increased, the decomposability is extremely lowered or the composition becomes non-decomposable. In addition, crosslinked saccharides such as crosslinked carboxymethylcellulose, crosslinked alginic acid, and crosslinked starch have many strong hydrogen bonds in their molecules, and therefore have strong interactions between molecules and between polymers. Can not open widely, absorption capacity is not high,
It was unsuitable as a water-absorbing polymer in sanitary articles.

[Technical Background of Polyamino Acid Diameter-Based Water Absorbent Resin] On the other hand, a resin obtained by crosslinking a polyamino acid is biodegradable and thus is friendly to the global environment. It is a material that is easy on humans because it has been shown that it is digested and absorbed, and that it does not show antigenicity in vivo and that degradation products have no toxicity.

[Demand for disposable hygiene articles] That is, there is a high demand for disposal of disposable hygiene articles.
There has been a strong demand for the emergence of new disposable sanitary materials including the treatment method.

[0010]

Accordingly, an object of the present invention is to provide a biodegradable sanitary article that solves the above-mentioned conventional problems.

[0011]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, completed the present invention. That is, the invention is specified by the following items [1] to [24].

[1] A sanitary article containing a crosslinked polyamino acid resin in an absorbent core.

[2] A sanitary article comprising an absorbent pad in which an absorbent core layer is covered with a coating layer, wherein the absorbent core layer comprises a crosslinked polyamino acid-based resin.

[3] A sanitary product having a laminated structure including a top sheet layer, an absorbent core layer, and a back sheet layer, wherein the absorbent core layer comprises a crosslinked polyamino acid resin. , The topsheet layer, and / or
Alternatively, the sanitary article, wherein the back sheet layer is configured to include a biodegradable polymer.

[4] 70-100 of the weight of all components
%. The sanitary article according to any one of [1] to [3], wherein% is composed of a biodegradable material.

[5] The sanitary article according to any one of [1] to [3], wherein 100% of the weight of all the constituent elements is made of a biodegradable material.

[6] The sanitary article according to [5], which has a function of biodegrading by composting.

[7] The sanitary article according to [6], wherein, when subjected to compost treatment, the total weight becomes 0 to 50% of the weight before the treatment in 40 days.

[8] The sanitary article according to any one of [1] and [5], which has a function of biodegrading by burying.

[9] The sanitary article according to [8], wherein when buried, the total weight becomes 0 to 50% of the weight before the processing in 6 months.

[10] The crosslinked polyamino acid resin is a crosslinked polyaspartic acid resin, [1] to [9].
The sanitary article described in any one of the above.

[11] The sanitary article according to [10], wherein the crosslinked polyaspartic acid-based resin has at least one of the following water-absorbing capacities (a) to (d). (A) Water absorption capacity in which the equilibrium swelling and absorption of physiological saline is 30 to 200 times per unit weight of polymer. (B) a water absorption capacity in which physiological saline is absorbed for 1 minute and the amount of absorption is 20 to 150 times per unit weight of the polymer; (C) a water absorption capacity in which the amount of physiological saline absorbed under a load of 20 g / cm ² is 15 to 150 times per unit weight of the polymer. (D) Water absorption capacity in which the centrifugal force of 3000 G can be held for 10 minutes in a gel saturated with physiological saline solution by 10 to 150 times per unit weight of polymer.

[12] The sanitary article according to [10], wherein the crosslinked polyaspartic acid-based resin has at least one of the following water absorbing properties (e) to (h). (E) Water absorption capacity in which the equilibrium swelling and absorption of artificial urine is 15 to 150 times per unit weight of polymer. (F) Water absorption capacity in which the amount of artificial urine absorbed for 1 minute is 10 to 150 times the polymer weight. (G) The water absorption capacity of the artificial urine under a load of 20 g / cm ² of 10 to 150 times the amount of water absorbed per unit weight of the polymer. (H) Water absorption capacity in which the gel that has saturatedly absorbed artificial urine can maintain a centrifugal force of 3000 G for 10 minutes in a water retention amount of 10 to 150 times per unit weight of polymer.

[13] The sanitary article according to any one of [3] to [12], wherein the biodegradable polymer comprises an aliphatic polyester.

[14] The sanitary article according to [13], wherein the aliphatic polyester contains at least a part of a polyhydroxycarboxylic acid.

[15] The polyhydroxycarboxylic acid is
The sanitary article according to [14], which comprises at least a part of polylactic acid.

[16] The sanitary article according to [14], wherein the aliphatic polyester contains, at least in part, a condensate of a dihydric alcohol and a dihydric carboxylic acid.

[17] The biodegradable disposable sanitary article according to [16], wherein the dihydric alcohol contains at least a part of 1,4-butanediol.

[18] The biodegradable disposable sanitary article according to [16] or [17], wherein the divalent carboxylic acid contains succinic acid in at least a part thereof.

[19] The biodegradable polymer is characterized in that it contains a polysaccharide at least in part.
The sanitary article according to any one of [3] to [18].

[20] The polysaccharide described in [19], wherein the polysaccharide comprises at least one selected from the group consisting of cellulose, chitin, chitosan, and starch. Sanitary supplies.

[21] The absorbent core (layer) according to any one of [1] to [20], wherein the absorbent core (layer) has at least one of the following water absorbing capacities (A) to (D). Sanitary goods. (A) The absorption rate for absorbing 20 ml of physiological saline is
Water absorption capacity of 0.1 to 50 ml / sec · cm ² . (B) The saturated absorption amount when physiological saline is absorbed is 0.
Water absorption capacity of 1 to 5 g / cm ² . (C) Water absorbency with a physiological saline absorption of 0.05 to 4 g / cm ² under a load of 20 g / cm ² . (D) When the load of 1 ton / m ² is applied to the saturated absorption when physiological saline is absorbed, the return is 0 to 0.
Water absorption capacity of 0.035 g / cm ² .

[22] The absorbent core (layer) containing the crosslinked amino acid-based resin has at least one of the following water absorbing capacities (A ′) to (D ′): [1]
Or the sanitary article according to any one of [20] to [20]. (A ′) a water absorption capacity in which the absorption rate of physiological saline per unit weight of the crosslinked amino acid-based resin is 20 to 250 times per minute. (B ′) a water absorption capacity in which the saturated absorption amount when absorbing physiological saline is 40 to 250 times per unit weight of the crosslinked amino acid-based resin. (C ′) 20 g per unit weight of crosslinked amino acid resin
/ Cm ² under a load of 25 to 18
Water absorption capacity which is 0 times. (D ') per unit weight of the cross-linked amino acid-based resin, 1 ton / m
Water absorption capacity with a reversal of 0 to 7 times when a load of ² is applied.

[23] The absorbent core (layer) according to any one of [1] to [20], wherein the absorbent core (layer) has at least one of the following water absorbing capacities (E) to (H). Sanitary goods. (E) The absorption rate of absorbing 20 ml of artificial urine is 0.1
Water absorption capacity of ５０50 ml / sec · cm ² . (F) The saturated absorption amount when artificial urine is absorbed is 0.05
Water absorption capacity of ４4 g / cm ² . (G) Under the load of 20 g / cm ² , the amount of artificial urine absorbed
Water absorption capacity of 0.03 to 3 g / cm ² . (H) Saturated absorption when artificial urine is absorbed 1
The reversion when applying a load of ton / m ² is 0 to 7 g /
Water absorption capacity which is cm ² .

[24] The absorbent core (layer) containing a cross-linked amino acid-based resin has at least one of the following water absorbing capacities (E ′) to (H ′): [1]
Or the sanitary article according to any one of [20] to [20]. (E ′) a water absorption capacity in which the rate of absorbing artificial urine per unit weight of the crosslinked amino acid-based resin is 15 to 200 times per minute. (F ′) a water absorption capacity in which the saturated absorption amount when artificial urine is absorbed is 20 to 200 times per unit weight of the crosslinked amino acid-based resin. (G ′) 20 g per unit weight of crosslinked amino acid resin
Water absorption capacity under which the artificial urine absorption amount is 20 to 150 times under a load of / cm ² . (H ′) Water absorption capacity in which, when a load of 1 ton / m ² is applied to a saturated absorption of artificial urine per unit weight of the crosslinked amino acid-based resin, a return is 0 to 7 times.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

(1) The type and shape of the sanitary article of the present invention
Design (Design), Style, and Size The sanitary ware of the present invention is not specified with respect to a specific type, shape, design (design), or style of the sanitary ware to be used, and generally used one can be selected.
That is, the present invention relates to the selection of a specific material of a sanitary ware in which the disposal treatment is taken into consideration. In particular, by using a crosslinked polyamino acid-based resin with high performance as a water-absorbing resin, it can exhibit excellent properties as a sanitary product,
A new method is presented as a method for treating the waste. For example, types of sanitary articles include children's paper diapers, adult paper diapers, sanitary napkins, tampons, panty liners, sanitary sheets, incontinence pads, medical blood absorbers, and the like. The sanitary ware of the present invention is not particularly distinguished in terms of its type, and can be used for any material that requires a function as an absorber. Also, the shape of the sanitary product is not specified. For example, in the case of disposable diapers, pants and
Examples include type, pad, type, mechanical fastener system type, and the like. Similarly, there is no distinction in the design (design) or style of use of the sanitary article of the present invention. Further, the size of the sanitary article of the present invention is not particularly limited, and the size can be selected according to the type, shape, design (design), and style of the sanitary article to be used.

(2) Structure of Sanitary Article of the Present Invention The structure of the sanitary article of the present invention is not particularly limited, and may be a structure used for general sanitary articles. The structure of the sanitary article of the present invention, the type, shape,
The size can be selected according to the design (design) and style. These are generally topsheets, backsheets,
It is basically composed of an absorbent core. However, the sanitary article is not necessarily composed only of these parts, and may include other necessary parts as needed. For example, in addition to the above parts, disposable diaper supplies include mechanical gatherings such as waist gathers, anti-leak gathers, inner leg gathers, outer leg gathers, frontal tape, adhesive, magic tape, fastener tape systems, release tape systems, and Velcro. A sunning system, a liquid diffusion layer, and the like. In addition, the sanitary article of the present invention may have a structure without a top sheet and / or a back sheet, if necessary. That is, an essential element of the sanitary article of the present invention is the absorbent core, and other sanitary articles including the absorbent core are not particularly limited, and the sanitary article can be constructed by combining various parts. Further, a single part may have two or more functions at the same time. For example, the absorbing core can have a diffusion function. In addition, composite of top sheet / acquisition layer, end cap / waist gather, release tape / fastening tape, composite of top sheet and side sheet, inner leg gather, etc., and composite of back sheet and absorber And a filmless composite. The sanitary article of the present invention can have not only a single structure but also a multiple structure. In particular, the absorption capacity can be enhanced by the structure in which the absorption cores are stacked.
These may be not only the structure of the entire sanitary article but also the structure of each part in a multiplex structure. For example,
Not only a structure in which the tissue layer / pulp layer / water-absorbent resin layer is vertically combined, but also a multilayer structure can be formed by combining them.

(3) Top sheet of the sanitary article of the present invention The top sheet of the sanitary article of the present invention is a part that allows liquid to permeate and guides the liquid to the absorbent core, and is not particularly limited, and those commonly known are used. it can. However, in consideration of waste treatment, which is one of the objects of the present invention, it is preferable that the entire structural material is biodegradable, and in this case, it is preferable that the top sheet be made of a biodegradable material. However, this is not an indispensable condition for the sanitary article of the present invention. If the absorbent core and the top sheet can be easily separated from each other and can be separated, they do not need to be composed of a biodegradable material.
The material constituting the top sheet of the sanitary material of the present invention will be described in detail in (7). The topsheet of the sanitary article of the present invention needs to be liquid-permeable, and examples thereof include a woven fabric, a nonwoven fabric, and a porous film. When these are used for applications in direct contact with the skin, those having a feeling similar to underwear are preferred. It is also preferable to use a mesh-type sheet having a high dry feeling or a dry nonwoven fabric because the amount of liquid remaining on the surface is reduced. The topsheet of the present invention may be a combination of a topsheet in a narrow sense as a structure and a skin contact sheet that is a part that comes into contact with the skin or the like. The topsheet of the sanitary article of the present invention can have not only a single structure but also a multiple structure. For example, a top sheet having a zebra structure composed of two layers, a hydrophobic side portion and a hydrophilic center portion, can be obtained from the viewpoint of the planar arrangement. The top sheet of the sanitary article of the present invention may contain a material having a deodorizing and deodorizing function, if necessary. Further, an antibacterial material for suppressing the propagation of bacteria can be contained. Furthermore, a method of applying a hydrophobic compound such as a silicone oil agent or paraffin wax to the peripheral portion, or a method of applying a hydrophilic compound such as an alkyl phosphate ester in advance to prevent leakage due to bleeding of urine or the like at the peripheral portion. I do not care. The top sheet of the sanitary article of the present invention is a liquid-permeable material, and in view of industrial production, a nonwoven fabric is particularly preferable. (7-
Details will be described in 2).

(4) Backsheet of the sanitary article of the present invention The backsheet of the present invention is not particularly limited as long as it does not allow liquid permeation, and any commonly known backsheet can be used. However, in consideration of waste treatment, which is one of the objects of the present invention, it is preferable that the entire structural material is biodegradable, and in this case, it is preferable that the backsheet be made of a biodegradable material. However, this is not an indispensable condition for the sanitary material of the present invention. If the absorbent core and the back sheet can be easily separated and subjected to a separation treatment, the absorbent core and the back sheet do not need to be composed of a biodegradable material. The top sheet of the sanitary article of the present invention needs to be liquid-impermeable, and examples thereof include a thermoplastic resin film, a composite material of a film and a nonwoven fabric, and a composite material of a film and a woven fabric. Depending on the intended use, these materials can prevent water permeation, but are preferably porous materials that can transmit water vapor. When these are used for applications in contact with the human body, those having softness are preferred.

The back sheet of the sanitary article of the present invention can have not only a single structure but also a multiple structure. The material constituting the backsheet of the sanitary material of the present invention will be described in detail in (7).

(5) Absorbent core of sanitary article of the present invention The absorbent core of the present invention is characterized by comprising a biodegradable material. The structure is made of pulp and a water-absorbing resin, and in some cases, can include absorbent paper (diffusion paper). The pulp is preferably defibrated pulp. The absorbent core of the sanitary article of the present invention can have not only a single structure but also a multiple structure. In particular, the absorption capacity can be enhanced by adopting a structure in which absorption layers are stacked or by giving a concentration gradient of the water-absorbing resin. For example, pulp layer / water-absorbent resin
A pulp composite layer / a double-phase absorber formed separately from the pulp layer and the like may be mentioned. The water absorbent resin in the absorbent core of the present invention,
It is a crosslinked polyamino acid resin. The details will be described in (6). The location of the water-absorbent resin is not particularly limited, and may be any of the upper layer, the middle layer, and the lower layer of the absorbent core, or may be a mixture with the pulp. A structure that can efficiently absorb body fluids and the like is preferable.
Further, it is preferable that the water-absorbing resin is dispersed so that its performance can be sufficiently exhibited. Therefore, a method of fixing the water-absorbing resin so that the water-absorbing resin is not unevenly distributed during the manufacturing process, the delivery of the product, the storage, or the like may be adopted. For example,
A method in which a thermoplastic resin is mixed into pulp and a part thereof is adhered by heat or the like, or a part is adhered by a binder, or the like is used. The binder resin is not particularly limited, but it is preferable to use a biodegradable polymer binder in order to exhibit the biodegradability that is the gist of the present invention. The absorbent paper of the present invention is not limited, but is usually a paper mainly composed of cellulose.

(6) Water-absorbing resin in the absorbent core of the sanitary article of the present invention The water-absorbing resin in the absorbent core of the sanitary article of the present invention is specified as a crosslinked polyamino acid. The cross-linked polyamino acid is not particularly limited, and a cross-linked polyamino acid can be used. The basic skeleton of the polyamino acid used in the present invention comprises a polypeptide in which amino acids are dehydrated and condensed. Specific examples of the amino acid component include, for example, 20 kinds of essential amino acids, L-ornithine, a series of α-amino acids, β-alanine, γ-aminobutyric acid, neutral amino acids, acidic amino acids, ω-esters of acidic amino acids, bases Amino acids, N-substituted basic amino acids, amino acids and amino acid derivatives such as aspartic acid-L-phenylalanine dimer (aspartame), and aminosulfonic acids such as L-cysteic acid. The α-amino acid is an optically active form (L
, D-form) or a racemic form. Further, the polyamino acid may be a copolymer containing another monomer component. Examples of the monomer component of the copolymer include aminocarboxylic acid, aminosulfonic acid, aminophosphonic acid,
Examples thereof include hydroxycarboxylic acid, mercaptocarboxylic acid, mercaptosulfonic acid, and mercaptophosphonic acid. Further, polyamines, polyhydric alcohols, polythiols, polycarboxylic acids, polysulfonic acids, polyphosphonic acids, polyhydrazine compounds, polycarbamoyl compounds,
Polyvalent sulfonamide compound, polyvalent phosphonamide compound, polyvalent epoxy compound, polyvalent isocyanate compound,
Examples include a polyvalent isothiocyanate compound, a polyvalent aziridine compound, a polyvalent carbamate compound, a polyvalent carbamic acid compound, a polyvalent oxazoline compound, a polyvalent reactive unsaturated bond compound, and a polyvalent metal. When it is a copolymer, it may be a block copolymer or a random copolymer. Also, it may be a graft.

Among these, polyaspartic acid, polyglutamic acid,
It is preferable to use polylysine as the basic skeleton, and it is preferable to use polyaspartic acid and glutamic acid having high water absorption as the basic skeleton, and particularly preferable is polyaspartic acid suitable for industrial production.

The side chain structure of the crosslinked polyamino acid used in the present invention may be a polyamino acid residue having no substituent or a polyamino acid residue containing a pendant group derived therefrom. Absent. In the case of polyaspartic acid, it is a group having a carboxyl group in a structure in which an imide ring is simply opened, but other substituents may be introduced. For example, there are a group having a carboxyl group in a structure in which an imide ring is simply opened, an amino acid residue such as lysine, a pendant group having a carboxyl group, and a pendant group having a sulfonic acid group. Here, in the case of a carboxyl group or a sulfonic acid group, a salt may be used. As the counter ion of the carboxyl group, alkali metal salts, ammonium salts,
Amine salts and the like.

In the case of an acidic polyamino acid, the carboxyl group or side chain group is substituted with an amide bond of the polymer main chain, and in the case of an aspartic acid residue, even if it is substituted at the α-position, it is substituted at the β-position. The glutamic acid residue may be substituted at the α-position or at the γ-position. In the case of a copolymer, in the case of polyaspartic acid and its copolymer, an α bond is formed when the amino group of the aspartic acid or the copolymer monomer and the carboxyl group at the α position of aspartic acid are bonded. ,
The case where the amino acid is bonded to the β-carboxyl group of aspartic acid is a β bond. In the case of polyaspartic acid, the α bond and the β bond are not particularly limited, and the bonding mode is not particularly limited. It may be only an α bond, only a β bond, or a mixture. The binding portion between the basic skeleton and the side chain portion of the polyamino acid of the present invention is not particularly limited.
In the case of an acidic polyamino acid, an amide bond, an ester bond,
It is a thioester bond. In the case of a carboxyl group, a salt may be formed even in a form in which a hydrogen atom is bonded. Examples of the counter ion of the carboxyl group include alkali metal salts, ammonium salts, and amine salts. The polyamino acid used in the present invention is a crosslinked product. The binding portion between the basic skeleton and the crosslinked portion of the present invention is not particularly limited. In the case of an acidic polyamino acid, it is an amide bond, an ester bond, or a thioester bond. These crosslinking portions and side chain portions may be unsubstituted or substituted. As the substituent, an optionally branched alkyl group having 1 to 18 carbon atoms, a cycloalkyl group having 3 to 8 carbon atoms, an aralkyl group,
A phenyl group which may be substituted, a naphthyl group which may be substituted, an optionally branched alkoxy group having 1 to 18 carbon atoms, an aralkyloxy group, a phenylthio group,
An optionally branched alkylthio group having 1 to 18 carbon atoms, an optionally branched alkylamino group having 1 to 18 carbon atoms, an optionally branched dialkylamino group having 1 to 18 carbon atoms, A trialkylammonium group having 1 to 18 carbon atoms which may be branched, a hydroxyl group,
Examples include an amino group, a mercapto group, a sulfonyl group, a sulfonic acid group, a phosphonic acid group and salts thereof, an alkoxycarbonyl group, an alkylcarbonyloxy group and the like. The basic skeleton, crosslinked portion, and side chain portion of these polyamino acid-based resins are not particularly limited, as long as they can exhibit sufficient water-absorbing ability as the absorbent resin contained in the absorbent core, regardless of the production method. Resins can also be used. As the crosslinked polyaspartic acid, resins produced by various methods can be used regardless of the production method. For example, a method of crosslinking a part of polysuccinimide with a polyamine and hydrolyzing the remaining imide ring with an alkali or the like, a method of mixing aspartic acid, polyaspartic acid and lysine, and crosslinking while polymerizing A method in which polyaspartic acid and a polyvalent amine are mixed and dehydrated and condensed at a high temperature, a method in which polyaspartic acid is reacted with a polyvalent glycidyl compound, and a method in which an aqueous solution of polyaspartic acid is irradiated with γ-rays. Any of the resins produced by these methods can be used irrespective of the production method as long as the resin can exhibit a sufficient water absorbing ability as the absorbent resin contained in the absorbent core. These resins may be used as a mixture of two types. Further, a crosslinked polysaccharide, which is another water-absorbing resin having biodegradability, may be used in combination. If necessary, a water-absorbing resin having no biodegradability may be used together as long as the biodegradability of the sanitary article is not impaired. The amount of the water-absorbing resin used in the present invention varies greatly depending on the type and amount of the body fluid for the purpose of absorption, and also depends on the intended use. Generally, 0.1 to 200 g per 1 m ^{2 of} sheet
Is preferable, and 1 to 50 g is particularly preferable. The shape of the crosslinked polyamino acid-based resin used in the present invention is irregularly crushed,
Various types such as a sphere, a granule, a granule, a granule, a scale, a lump, a pearl, a fine powder, a fiber, a bar, a film, and a sheet can be used, and a preferable shape can be used depending on the application. Further, it may be a fibrous base material, a porous material, a foam, or a granulated material. The particle size of these crosslinked polyamino acid-based resins is not particularly limited, but varies depending on the intended use. For example, in the case of a disposable diaper, it is desired that a high absorption rate and gel blocking do not occur.
0 to 600 μm is more preferable. The crosslinked polyamino acid-based resin used in the sanitary article of the present invention needs to have excellent water absorbing ability. In particular, it is necessary that the water absorption under a non-load is large, the water absorption under a load is large, the water retention under a load is large, and the water absorption speed is high. For example,
Although the sanitary material must be able to absorb various body fluids sufficiently, in the present invention, physiological saline is used as a standard of the body fluid to represent the water absorbing ability of the water-absorbing resin. That is, the crosslinked polyamino acid-based resin used as the water-absorbing resin in the sanitary article of the present invention preferably has the following water-absorbing ability.
For example, (a) the equilibrium swelling amount of physiological saline is 30 times or more based on the weight of the polymer, and (b) the amount of physiological saline absorbed for 1 minute is 20 times or more based on the weight of the polymer. (C) the water absorption under a load of 20 g / cm ² is at least 15 times the polymer unit weight;
(D) The amount of water retention that can hold the centrifugal force of 3000 G for 10 minutes on the gel saturated with physiological saline is 10 times or more per unit weight of the polymer. Further, those having the following water absorbing ability are more preferable. (A) The equilibrium swelling absorption amount of physiological saline is 40 times or more based on the polymer unit weight, and (b) The absorption amount of physiological saline absorbed for 1 minute is 30 times or more based on the polymer unit weight. And (c) the amount of water absorption under a load of 20 g / cm ² is at least 20 times the unit weight of the polymer. (D) A centrifugal force of 3000 G was applied to the gel saturated with physiological saline for 1 hour.
The water retention amount that can be maintained over 0 minutes is 20 times or more per unit weight of the polymer. Furthermore, those having the following water absorbing ability are particularly preferred. (A) The equilibrium swelling absorption amount of physiological saline is 50 times or more with respect to the polymer unit weight, and (b) The absorption amount of physiological saline absorbed for 1 minute is 35 times or more with respect to the polymer unit weight. And (c) the amount of water absorption under a load of 20 g / cm ² is at least 25 times the unit weight of the polymer. (D) A centrifugal force of 3000 G was applied to the gel saturated with physiological saline for 1 hour.
The water retention that can be maintained over 0 minutes is 25 times or more per unit weight of the polymer. Although there is no upper limit to these values, those showing a high number are preferable, but when the upper limit is set within the range of common sense of crosslinked polyamino acid-based resins that can be actually produced, those having the following water absorbing ability are preferable. For example,
(A) the equilibrium swelling and absorption of physiological saline is 30 to 200 times the polymer unit weight;
20 minutes per unit weight of polymer
(C) The water absorption under a load of 20 g / cm ² is 15 to 150 times the polymer unit weight. (D) 3000 G of a gel saturated with physiological saline is absorbed.
Is 10 to 150 times the polymer weight per unit weight of the polymer. In the present invention, these values have upper limits. However, it is not impossible to use a resin having higher performance as the sanitary material of the present invention. Similarly, a resin having the following water supply ability for artificial urine is preferable. For example, (e) the equilibrium swelling and absorption of artificial urine is 15 to 150 times the polymer unit weight,
(F) the amount of artificial urine absorbed for 1 minute is 10 to 150 times the polymer unit weight, (g) 20 g / c
The amount of water absorbed by artificial urine under a load of m ² is 10 to 150 times the unit weight of the polymer. (h) The water retention amount capable of holding a centrifugal force of 3000 G for 10 minutes on a gel having saturated absorption of artificial urine Is 10 to 150 times per unit weight of the polymer.

The water-absorbing resin used in the present invention may be added with an inorganic compound such as salt, colloidal silica, white carbon, ultrafine silica, titanium oxide powder, or an organic compound such as a chelating agent, if necessary. . Further, an oxidizing agent, an antioxidant, a reducing agent, an ultraviolet absorber, an antibacterial agent, a bactericide, a fungicide, a fertilizer, a fragrance, a deodorant, a pigment and the like may be mixed.

(7) Materials Constituting the Topsheet and the Backsheet of the Sanitary Ware of the Present Invention The materials forming the backsheet and the topsheet of the sanitary ware of the present invention are not particularly limited. preferable. As a material constituting the top sheet and the back sheet, for example, non-sized paper, nonwoven fabric, polyethylene, polypropylene, hydrophilic polyethylene,
Water-permeable porous sheets such as polypropylene, cellophane,
Vinylon film, PVA film, thermoplastic film foamed so as to have fine communication holes at the time of film production, inorganic or high melting point nucleating agent added and stretched to form fine communication holes, polyethylene Paper and mixed paper of polypropylene and pulp, laminate of paper and non-woven fabric, size paper or non-woven fabric with cellulose film formed by viscose, cellulose film with fine pores formed, thermoplastic resin Plastic film, polyethylene paper, metal foil, part or all of which are thermoplastic nonwoven fabric, rayon, fibers such as pulp, impregnated or mixed with resin such as polyolefin, polyester, polyamide, etc., polyolefin, polyester, polyamide, etc. A non-woven fabric made of a resin may be used. Further, the biodegradable material constituting the top sheet and the back sheet in the present invention includes a biodegradable polymer material, and is classified into a non-meltable material and a fusible material. Examples of the non-melting material include pulp, cotton, wool, regenerated cellulose fiber, and solvent-spun cellulose fiber. Examples of the pulp include virgin pulp from wood and pulp recovered from waste paper. Examples of the fusible material include aliphatic polyester and aliphatic polyesteramide. Examples of aliphatic polyesters include:
Polyglycoside, poly (α-hydroxycarboxylic acid) such as polylactic acid, poly-ε-caprolactone, poly-β
-Propiolactone, poly-3-hydroxypropionate, poly-3-hydroxybutyrate, poly-3-hydroxycaprolate, poly-3-hydroxyheptanoate, poly-3-hydroxyoctanoate, and Polyhydroxyalkanoates such as copolymers thereof with poly-3-hydroxyvalerate and poly-4-hydroxybutyrate, polyethylene oxalate, polyethylene succinate, polybutylene succinate, polybutylene adipate polybutylene sebacate Condensates of dihydric alcohols and dicarboxylic acids, such as polyhexamethylene sebacate, polyneopentyl oxalate and copolymers thereof, and further having a urethane bond obtained by chain-extending them with a divalent isocyanate compound And the like. Examples of aliphatic polyester amides include ε
And lactone and lactam copolymers such as -caprolactone and ε-caprolactam copolymer.

(7-2) Nonwoven fabric forming the topsheet and backsheet of the sanitary article of the present invention The nonwoven fabric according to the ASTM is “a web in which fibers are joined together by a joining material, or a cloth-like material having a mat-like structure”. According to the Japan Non-woven Fabric Association, "Dry-type webs are made by combining and adhering constituent fibers by mechanical, thermal, or a combination thereof. In the present invention, a natural or artificial fiber staple or continuous filament is used as an adhesive, a molten fiber, or a mechanical method. Are defined as "a cloth-like substance joined by". The production method is not particularly limited, and various methods can be used. For example, without using water as a medium, a dry method in which a fiber sheet is formed by a card for spinning or a garnet or other device, a method in which raw fibers are dispersed in a liquid containing water or a binder, and a paper machine is used. And a direct method of forming a fiber and simultaneously forming a nonwoven fabric. The dry method comprises a step of loosening or mixing a raw material fiber with a cotton opener or a compounding machine to form a thin sheet (web), and a step of joining the obtained web. The web is made by crossing and arranging a parallel array of webs made of cards or garnets, and by crossing and folding the webs, the blown fibers are blown off by an air stream to uniformly disperse and collect them on a perforated cylinder (condenser). -Lay) to produce a random sequence web. A nonwoven fabric may be formed using short fibers such as sulfite pulp or cotton linter without using an adhesive. Web joining methods include an adhesive method and a mechanical joining method. The method using an adhesive includes a dipping method, a roll method, a foaming method, a printing method, a spray method using a synthetic resin solution or an emulsion, a method using synthetic resin powder, and a method using fibers as a bonding material. The mechanical joining method includes a needle punch method and a stitch method. In the wet method, fine irregular branch-like binders (fibrids) made of a thermoplastic resin are mixed with ordinary fibers in a wet pulp-like state to form a slurry, formed into a sheet by a paper machine, and heated. Then, there is a method of melting and joining the fibrids, and a method of mixing a multicellular self-bonding viscose rayon or the like with various kinds of fibers to form a slurry in water, forming a mat by a wet method, and drying.
Also, fibrillated fibers can be used in a similar manner. The direct method includes a spray fiber method and a spun bond method. In the spray fiber method, the raw polymer material is melted or hot-melted and sprayed from a spinning nozzle, blown off by an air stream sprayed from around the nozzle to form cut fibers, and accumulated on a conveyor screen. When forming a random mat composed of extremely fine fibers, the spinning cylinder is uniformly dispersed by applying static electricity. In the spunbond method, a filament melt-spun from a spinning nozzle is guided into a suction jet, and is drawn downward as it is drawn by a compressed air flow.The filament is charged by static electricity applied to the suction jet and uniformly opened. It is a method of forming a uniform random web in the lower receiver. The raw material fiber used as the material for the nonwoven fabric used in the sanitary ware of the present invention is preferably a polymer material having biodegradability. As examples thereof, those described in (7) can be used. The adhesive used for producing the nonwoven fabric of the present invention is preferably a polymer material having biodegradability. For example, a hot melt adhesive described in (8) can be used.

(8) Method for Producing the Sanitary Article of the Present Invention The method for producing the sanitary article of the present invention is not particularly limited, and a generally used method can be used. In general, there is a method in which an inner layer material such as an absorbent core is integrated with an outer layer material such as a top sheet and a back sheet by heat sealing, high frequency bonding or the like using a binder, an adhesive or the like. The steps of manufacturing the final sanitary ware and the absorbent core may be performed simultaneously or in separate steps. For example, a composition containing a water-absorbent resin and a binder is evenly sprayed on the inner layer material, the other inner layer materials forming the absorbent core are overlapped, and the resultant is sandwiched and integrated through a heated embossing roll. The base paper can be manufactured by cutting the base paper to a predetermined size, hand-packing the base paper into an outer layer material made of a three-side seal pouch, and passing the whole through a heated embossing roll to be integrated. Here, the material of the inner layer and the outer layer is not limited to a single layer, and an appropriate laminate composed of multiple layers can be used. The method of sandwiching and integrating through the heated embossing roll includes: a. Between a heated embossing roll and a heated embossing roll, b. Between a heating embossing roll and a heating roll, c. Between a heated embossing roll and a roll, d. Between a heating roll and a heating roll, e. A method of passing through and integrating any one of the heating rolls and the rolls is exemplified. The method for uniformly spraying the water-absorbing resin on a support such as pulp is not particularly limited. For example, a method of spraying by vibration, a method of placing a water-absorbent resin on a roll having many holes capable of holding the water-absorbent resin, and a spray, supporting a slurry of a mixed liquid of water containing a water-absorbent resin and a water-miscible organic solvent. Examples of the method include a method in which the solvent is removed by drying on a body, and a method in which a gel of a water-absorbent resin is placed on a support and the solvent is removed by a heat roller or the like. The adhesive connecting each part of the sanitary ware of the present invention includes a hot melt adhesive. It is preferable that the hot melt adhesive is also made of a biodegradable material. For example, it comprises the fusible polymer material described in (7), an organic solvent such as glycerin, and an antioxidant.
Further, as a specific example, a hot melt adhesive composed of polycaprolactone / polybutylene succinate / glycerin / antioxidant can be mentioned.

(9) Sanitary Goods Waste Disposal Method One of the features of the sanitary ware of the present invention lies in its waste disposal method. Since the sanitary article of the present invention is made of a biodegradable material, its treatment is characteristic. However, this is not an indispensable condition for the sanitary article of the present invention. If the absorbent core and the top sheet and / or the back sheet can be easily separated and separated, the part composed of the biodegradable material is not included. Parts can also be processed separately.
In this case, the treatment method of the present invention is applied to treatment of a portion made of a biodegradable material. Sanitary article waste refers to waste containing the target absorbed body fluid and the like. Pre-processing can be performed as needed to perform the processing of the present invention. For example, a drying treatment, a sterilization treatment, a shredding treatment and the like can be mentioned. In particular, shredding is an effective pretreatment because the rate of biodegradability increases. In addition, when used in hospitals and the like, it is an effective method to perform sterilization as a measure against pathogenic bacteria and the like. The method for treating waste composed of the biodegradable material of the present invention is not particularly limited. However, compost processing and burial processing are mentioned as effective and characteristic methods. By these treatments, it is preferable that 50 to 100% of the weight of all the components of the sanitary article is biodegradable, and it is particularly preferable that the biodegradation is 70 to 100%. When the top sheet or the back sheet is made of a non-biodegradable material, it is preferable that 70 to 100% of the remaining weight is biodegraded after separation and collection, and 80 to 100% decomposed. Is more preferable.
The method for composting the sanitary article waste of the present invention is not particularly limited, and a generally used method can be used. For example, a method of composting in the open air or a composter may be used. It is preferable that the waste of the sanitary article of the present invention is biodegraded at an early stage when treated with compost, and becomes a safe low-molecular compound. For example, practically, it is preferable that the total weight be 0 to 50% of the weight before processing in 40 days. Furthermore, 0 to 50% of the total weight before processing in 3 weeks
Is more preferable. The method of burying the waste of the sanitary article of the present invention is not particularly limited, and a generally used method can be used. It is preferable that the waste of the sanitary article of the present invention is biodegraded early when it is buried, and becomes a safe low-molecular compound. For example, practically, when burial treatment is performed, it is preferable that the total weight be 0 to 50% of the weight before treatment in 6 months.

(10) Types and Uses of Sanitary Articles The types of sanitary materials of the present invention can be used, for example, in disposable diapers, incontinence pads, sanitary napkins and the like. For example, sanitary articles such as sanitary articles, disposable diapers, breast milk pads, disposable rags, dressing materials for wound protection, medical underpads, medical supplies such as cataplasms, pet sheets, portable toilets, gel fragrances, gel deodorants Agents, sweat absorbing fibers and the like.

[0053]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the examples. In the following Examples and Comparative Examples, “parts” means “parts by weight”. In the present invention, the water absorbing ability of the water absorbing resin, the water absorbing ability of the absorber, and the biodegradability of the absorbent pad were measured.

(1) Measurement of Water Absorbing Capacity of Water Absorbing Resin The water absorbing capacity of the water absorbing resin in Examples was measured for physiological saline and artificial urine, and the water absorption capacity under equilibrium swelling, water absorption rate, and load. And water retention. The used physiological saline and artificial urine are as follows, respectively.

Physiological saline The physiological saline used is a 0.9% by weight aqueous solution of sodium chloride.

Artificial urine The artificial urine used was an aqueous solution having the following composition. Urea 1.94% by weight Sodium chloride 0.80% by weight Calcium chloride 840ppm Magnesium sulfate 2050ppm (1-1) Measurement of equilibrium swelling and water absorption of water-absorbent resin Equilibrium swelling and water absorption of water-absorbing resin is measured using a tea bag method. did. That is, about 0.1 part of a water-absorbent resin is placed in a non-woven tea bag (80 mm × 50 mm), immersed in an excess of a corresponding solution to swell the resin for one hour,
After the tea bag was pulled out and drained for 1 minute, excess water was absorbed by a large amount of tissue paper, and the weight of the tea bag containing the swollen resin was measured. The value obtained by subtracting the weight of the blank and the weight of the water-absorbent resin from the weight of the tea bag containing the swollen resin is divided by the weight of the water-absorbent resin assuming that the same operation was performed using only the teabag as a blank. The amount of water absorption (g / g of resin) was determined. The physiological saline is a 0.9% by weight aqueous sodium chloride solution.

(1-2) Measurement of Water Absorption Rate of Water Absorbent Resin As in the measurement of the equilibrium swelling and water absorption, 0.1 part of the resin was immersed in a physiological saline solution by the tea bag method.
The absorption amount after one minute was measured.

(1-3) Measurement of Water Absorption under Weight of Water Absorbent Resin Using 1 part by weight of resin, under a load of 1.5 kg / cm ² , water was absorbed by a water demand method. One hour later, the amount of water absorbed under a load was measured.

(1-4) Measurement of Water Retention Amount of Water Absorbent Resin Using 0.1 part of the resin, the gel which had been swollen and absorbed in equilibrium was placed in a centrifuge and centrifuged at 3000 G for 10 minutes.
The amount of water retained was measured.

(2) Measurement of Water Absorption Capacity of Absorber The water absorption capacity of the absorber in the examples was determined by measuring 10 parts of the water absorbing resin.
Using a sandwich structure prepared by dispersing between 2.7 parts of pulp and 2.7 parts of pulp reduced to 0 cm ² , saturated water absorption rate, water absorption rate, and water absorption under load for physiological saline and artificial urine The amount and wetback were performed. Similarly, as an absorber containing a large amount of water-absorbent resin, using a sandwich structure prepared by dispersing 5 parts of water-absorbent resin between 2.5 parts of pulp having 100 cm ² and 2.5 parts of pulp, For physiological saline and artificial urine, saturated water absorption, water absorption speed,
Water absorption under load and wet back were performed.

(2-1) Measurement of Water Absorption Rate of Absorber The absorption rate of the absorber was measured by absorbing 20 ml of the liquid to be absorbed.

(2-2) Measurement of Saturated Water Absorption of Absorber The saturated water absorption of the absorber was measured by a water demand method, and the water absorption after one hour was measured.

(2-3) Measurement of Water Absorption Under Load of Absorber The water absorption under load of the absorber was measured by a water demand method under a load of 20 g / cm ² , and the water absorption after 1 hour was measured. Was measured.

(2-4) Measurement of Wet Back of Absorber The absorber was measured by absorbing water by the water demand method and saturating and absorbing the liquid that had returned when a load of 1 ton / m ² was applied. A large amount of tissue paper was sucked and the weight was measured.

(3) Measurement of Biodegradability of Absorbent Pad The biodegradability of the absorbent pad in Examples was 2.5 parts of pulp obtained by changing 10 parts of water absorbent resin to 200 cm ² and 2.5 parts of pulp.
The absorbent pad dispersed between the parts is sandwiched between a biodegradable polymer nonwoven fabric and a sheet, and an absorbent pad bonded by heat using polycaprolactone / polybutylene succinate / glycerin / antioxidant as a bonding agent. The biodegradability in compost and the biodegradability due to burial were measured.

(3-1) Measurement of biodegradability of absorbent pad in compost The biodegradability of the absorbent pad in compost was measured by the compost method. The compost method is ASTM D-53
The measurement was performed according to ISO CD14855, which is an application of 38.92. That is, first, the test sample was biodegraded at 58 ° C. for 40 days in addition to 800 parts of the inocula, and the degree of decomposition of the absorbent pad was visually observed. When the non-decomposed product remained, the weight of the taken out decomposition residue was measured, and the change in weight with respect to the original constituent material was represented by the decomposition rate (%).

(3-2) Measurement of biodegradability of buried absorbent pad To measure the biodegradability of buried absorbent pad, test sample was buried 30 cm from the ground, biodegraded for 6 months, and absorbed. The degree of decomposition of the pad was visually observed. When the non-decomposed product remained, the weight of the taken out decomposition residue was measured, and the change in weight with respect to the original constituent material was represented by the decomposition rate (%).

Compound Production Example 1 7.2 parts of lysine methyl ester dihydrochloride and 22.6 parts of lysine monohydrochloride were dissolved in 40 parts of distilled water, and 7.8 parts of caustic soda was added little by little. Neutralized and prepared lysine aqueous solution. On the other hand, under nitrogen stream, 100 parts of polysuccinimide having a weight average molecular weight of 96,000 was dissolved in 400 parts of DMF, an aqueous lysine solution was added, and the mixture was stirred at room temperature for 1 hour, stopped stirring, and reacted for 20 hours. The reaction product was transferred to a mixer equipped with a blade with stirring blades, and 400 parts of distilled water and 400 parts of methanol were added.
The gel was shredded at 00 rpm for 5 minutes, and further 27% by weight.
129.7 parts of aqueous sodium hydroxide solution was added dropwise over 2 hours. After the dropwise addition, the mixture was further stirred for 2 hours, and then neutralized with 7% by weight aqueous hydrochloric acid until pH = 7. After the neutralization, 300 parts of methanol was further added, and the precipitate was dried at 60 ° C. to obtain 143 parts of a water-absorbing polymer. Further, the mixture was pulverized using a sample mill and classified to 100 to 500 μm. When the water absorption capacity of this resin was measured, the equilibrium swelling absorption amount with respect to physiological saline was 58 times, the water absorption rate was 27 times per minute, and the water absorption amount under load was 23 times,
The water retention was 28 times. For artificial urine, the equilibrium swelling absorption is 38 times and the water absorption rate is 2 times per minute.
The water absorption under load was 23 times and the water retention was 23 times.

[Compound Production Example 2] 3.0 parts of hexamethylenediamine was dissolved in 40 parts of DMF, and 7.8 parts of caustic soda was added little by little to neutralize to prepare an aqueous lysine solution. On the other hand, under nitrogen stream, 100 parts of polysuccinimide having a weight average molecular weight of 153,000 was dissolved in 400 parts of DMF, a lysine aqueous solution was added to this solution, and the mixture was stirred at room temperature for 1 hour, stopped stirring, and reacted for 20 hours. Thus, a gel of crosslinked polysuccinimide was obtained. The gel of crosslinked polysuccinimide was transferred to a mixer equipped with a blade with a stirring blade, 400 parts of distilled water and 400 parts of methanol were added, and 8000 rpm was added.
The gel was ground for 5 minutes.

Further, while maintaining the degree of swelling of the resin within the range of 3 to 100 times, 129.7 parts of a 27% by weight aqueous solution of caustic soda was dropped therein over 2 hours. After completion of the dropwise addition, the mixture was further stirred for 2 hours, and then neutralized to pH 7 by adding 7% by weight aqueous hydrochloric acid. After the neutralization was completed, 300 parts of methanol was further added, and the precipitate was dried at 60 ° C. to obtain a crosslinked polyaspartic acid-based resin 12 as a water-absorbing polymer.
5 parts were obtained. When the water absorption capacity of this resin was measured, the equilibrium swelling absorption was 64 times, the water absorption rate for physiological saline was 28 times per minute, the water absorption under load was 28, and the water retention was It was 35 times. For artificial urine, the equilibrium swelling absorption is 42 times, the water absorption rate is 27 times per minute, and the water absorption under load is 26 times.
The water retention was 26 times.

[Absorbent Production Example 1] An absorber of 100 cm ² was produced using 5 parts of the crosslinked polyamino acid-based resin and 5 parts of pulp produced in Compound Production Example 1, and the absorption capacity was measured. For physiological saline, the water absorption rate is 0.55 ml / sec · cm ² , the saturated water absorption is 2.5 g / cm ² , and the water absorption under load is 1.8 g / c.
m ² and the wet back was 0.006 g / cm ² . For artificial urine, the water absorption rate is 0.58 ml / s
a ec · cm ^2, the saturated water absorption is 1.8 g / cm ^2, under a load water absorption is 1.3 g / cm ^2, wetback was 0.007 g / cm ^2.

[Absorbent Production Example 2] An absorbent of 100 cm ² was produced using 5 parts of the crosslinked polyamino acid-based resin and 5 parts of pulp produced in Compound Production Example 2, and the absorption capacity was measured. For physiological saline, the water absorption rate is 0.53 ml / sec · cm ² , the saturated water absorption is 3.0 g / cm ² , and the water absorption under load is 2.7 g / c.
m ² , and the wet back was 0.003 g / cm ² . For artificial urine, the water absorption rate is 0.62 ml / s
a ec · cm ^2, the saturated water absorption is 1.9 g / cm ^2, under a load water absorption is 1.5 g / cm ^2, wetback was 0.005 g / cm ^2.

[Example 3 of Absorbent Production] One part of the crosslinked polyamino acid resin produced in Example 2 of compound production and 5.4 pulp
A 100 cm ² absorber was manufactured using the part, and its absorption capacity was measured. Per unit weight of the crosslinked polyamino acid-based resin, the water absorption rate was 65 times with respect to physiological saline, and the saturated water absorption was 95 times and water absorption under load is 5
It was 8 times and the wet back was 0.5 times. For artificial urine, the water absorption rate was 41 times, the saturated water absorption was 64 times, the water absorption under load was 50 times, and the wet back was 0.6 times.

[Absorbent Pad Production Example 1] Using the crosslinked polyamino acid-based resin produced in Compound Production Example 1, an absorbent pad was produced using polylactic acid for the nonwoven fabric and the backsheet, and its biodegradability was measured. However, in the compost, it was biodegraded so as not to leave any trace, and even when buried, it was biodegraded to such an extent that it could not be visually identified. The biodegradation rates were both 100%.

[Absorbent Pad Production Example 2] Using the cross-linked polyamino acid-based resin produced in Compound Production Example 1, polybutylene succinate (trade name;
Bionole, manufactured by Showa High Polymer Co., Ltd.) was used to produce an absorbent pad, and its biodegradability was measured. In the compost, it was biodegraded without leaving any traces. It was biodegradable to an indistinguishable degree. The biodegradation rates were both 100%.

[Production Example 3 of Absorbent Pad] Using the crosslinked polyamino acid-based resin produced in Production Example 2 of the compound, polylactic acid was used for the nonwoven fabric, and polybutylene succinate was used for the nonwoven fabric of cellulose (trade name: Bionole, An absorbent pad was manufactured using a dry-laminated film of Showa Kogaku Co., Ltd.), and its biodegradability was measured. In the compost, biodegradation was observed without leaving any traces, and it was buried. In the case of, the biodegradation was such that it could not be discerned visually. The biodegradation rates were both 100%.

[Production Example 4 of Absorbent Pad] Using the cross-linked polyamino acid resin produced in Production Example 2 for compound, dry lamination of polylactic acid for the nonwoven fabric and polylactic acid for the nonwoven fabric of chitin and chitosan for the backsheet An absorbent pad was manufactured using this film, and its biodegradability was measured.In the compost, it was biodegraded without leaving any trace, and even when buried, biodegradation was indistinguishable. Was. The biodegradation rate is
Both were 100%.

[Comparative Example of Compound] The water absorption capacity of the crosslinked carboxymethylcellulose having biodegradability was measured. The amount of equilibrium swelling and absorption was 36 times, and the rate of water absorption in physiological saline was 12 times per minute. The water absorption under load was 12 times and the water retention was 15 times.

[Comparative Example 1 for Production of Absorbent Material] An absorbent of 100 cm ² was produced using 5 parts of resin and 5 parts of pulp of the compound comparative example, and its absorption capacity was measured. Water absorption rate is 0.85 ml / sec · cm ²
The saturated water absorption was 2.2 g / cm ² , the water absorption under load was 0.8 g / cm ² , and the wet back was 0.024 g / cm ² . For artificial urine, the water absorption rate is 0.88 ml / sec · cm ² , the saturated water absorption is 1.8 g / cm ² , and the water absorption under load is 0.7
g / cm ² , with a wet back of 0.037 g / c
m ² .

[Comparative Example 2 for Production of Absorbent Material]
Not 100cm^TwoOf absorbent material and its absorption capacity
And measured the water absorption rate for physiological saline
Is 0.45 ml / sec · cm ^TwoAnd the saturated water absorption is
0.8g / cm^TwoAnd the water absorption under load is 0.5 g / c
m ^TwoAnd the wet back is 0.040 g / cm^TwoIn
Was. For artificial urine, the water absorption rate is 0.48 ml / s
ec · cm^TwoAnd the saturated water absorption is 1.7 g / cm^TwoIn
And the water absorption under load is 0.7 g / cm^TwoAnd wet
The back is 0.040 g / cm^TwoMet.

[Comparative Example of Absorbent Pad Production] An absorbent pad was produced using a cross-linked polyacrylic resin and a non-woven fabric and a backsheet made of polyethylene, and the biodegradability was measured. Except for the pulp part, no biodegradation was observed.

[0082]

EFFECTS OF THE INVENTION A gel having excellent gel stability and being decomposable after use or disposal can be obtained, which is friendly to the global environment and has excellent water absorbing ability.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) A61F 13/46 C08L 67/02 5/44 67/04 C08L 1/02 77/04 3/02 B01J 20 / 26 H 5/08 A41B 13/02 M 67/02 D 67/04 A61F 13/18 383 77/04 // B01J 20/26 (72) Inventor Hiroaki Tamaya 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Chemicals Co., Ltd. In-house F-term (reference) 3B029 BA18 BD21 4C003 AA07 AA23 AA26 HA04 4C098 AA09 CC02 CE05 CE06 DD05 DD14 DD23 DD26 DD30 4G066 AB06A AB07A AB27A AC01A AC02B AC02C AC23B AC33B AC35B AD15B BA05 AB04 CF18 AB11 CF04 GB01

Claims (24)

[Claims] 1. A sanitary article containing a crosslinked polyamino acid-based resin in an absorbent core. 2. A sanitary article comprising an absorbent pad having an absorbent core layer covered with a coating layer, wherein the absorbent core layer comprises:
A sanitary article comprising a crosslinked polyamino acid-based resin. 3. A sanitary product having a laminate structure including a top sheet layer, an absorbent core layer, and a back sheet layer, wherein the absorbent core layer comprises a crosslinked polyamino acid-based resin, The topsheet layer, and / or
The sanitary article, wherein the back sheet layer includes a biodegradable polymer. 4. The sanitary article according to claim 1, wherein 70 to 100% of the weight of all components is made of a biodegradable material. 5. The sanitary article according to claim 1, wherein 100% of the weight of all components is made of a biodegradable material. 6. The sanitary article according to claim 5, which has a function of biodegrading by composting. 7. The sanitary article according to claim 6, wherein when composted, the total weight is 0 to 50% of the weight before the treatment in 40 days. 8. The sanitary article according to claim 1, which has a function of biodegrading by burying. 9. The sanitary article according to claim 8, wherein when buried, the total weight is 0 to 50% of the weight before the treatment in 6 months. 10. The sanitary article according to claim 1, wherein the crosslinked polyamino acid resin is a crosslinked polyaspartic acid resin. 11. The sanitary article according to claim 10, wherein the crosslinked polyaspartic acid-based resin has at least one of the following water absorbing capacities (a) to (d). (A) Water absorption capacity in which the equilibrium swelling and absorption of physiological saline is 30 to 200 times per unit weight of polymer. (B) a water absorption capacity in which physiological saline is absorbed for 1 minute and the amount of absorption is 20 to 150 times per unit weight of the polymer; (C) a water absorption capacity in which the amount of physiological saline absorbed under a load of 20 g / cm ² is 15 to 150 times per unit weight of the polymer. (D) Water absorption capacity in which the centrifugal force of 3000 G can be held for 10 minutes in a gel saturated with physiological saline solution by 10 to 150 times per unit weight of polymer. 12. The sanitary article according to claim 10, wherein the crosslinked polyaspartic acid-based resin has at least one of the following water absorbing capacities (e) to (h). (E) Water absorption capacity in which the equilibrium swelling and absorption of artificial urine is 15 to 150 times per unit weight of polymer. (F) Water absorption capacity in which the amount of artificial urine absorbed for 1 minute is 10 to 150 times the polymer weight. (G) The water absorption capacity of the artificial urine under a load of 20 g / cm ² of 10 to 150 times the amount of water absorbed per unit weight of the polymer. (H) Water absorption capacity in which the gel that has saturatedly absorbed artificial urine can maintain a centrifugal force of 3000 G for 10 minutes in a water retention amount of 10 to 150 times per unit weight of polymer. 13. The sanitary article according to claim 3, wherein the biodegradable polymer comprises an aliphatic polyester. 14. The sanitary article according to claim 13, wherein the aliphatic polyester contains at least a part of a polyhydroxycarboxylic acid. 15. The sanitary article according to claim 14, wherein the polyhydroxycarboxylic acid contains at least a part of polylactic acid. 16. The sanitary article according to claim 14, wherein the aliphatic polyester contains at least a part of a condensate of a dihydric alcohol and a dicarboxylic acid. 17. The biodegradable disposable sanitary article according to claim 16, wherein the dihydric alcohol contains at least a part of 1,4-butanediol. 18. The biodegradable disposable hygiene article according to claim 16, wherein the divalent carboxylic acid contains succinic acid at least in part. 19. The sanitary article according to claim 3, wherein the biodegradable polymer contains at least a part of a polysaccharide. 20. The polysaccharide according to claim 19, wherein the polysaccharide comprises at least one selected from the group consisting of cellulose, chitin, chitosan, and starch. Sanitary goods. 21. An absorbent core (layer) comprising:
The sanitary article according to any one of claims 1 to 20, which has at least one of the water absorbing ability described in (D). (A) The absorption rate for absorbing 20 ml of physiological saline is
Water absorption capacity of 0.1 to 50 ml / sec · cm ² . (B) The saturated absorption amount when physiological saline is absorbed is 0.
Water absorption capacity of 1 to 5 g / cm ² . (C) Water absorbency with a physiological saline absorption of 0.05 to 4 g / cm ² under a load of 20 g / cm ² . (D) When the load of 1 ton / m ² is applied to the saturated absorption when physiological saline is absorbed, the return is 0 to 0.
Water absorption capacity of 0.035 g / cm ² . 22. The absorbent core (layer) containing a crosslinked amino acid-based resin has at least one of the following water absorbing capacities (A ′) to (D ′). The sanitary article described in any one of the above. (A ′) a water absorption capacity in which the absorption rate of physiological saline per unit weight of the crosslinked amino acid-based resin is 20 to 250 times per minute. (B ′) a water absorption capacity in which the saturated absorption amount when absorbing physiological saline is 40 to 250 times per unit weight of the crosslinked amino acid-based resin. (C ′) 20 g per unit weight of crosslinked amino acid resin
/ Cm ² under a load of 25 to 18
Water absorption capacity which is 0 times. (D ') per unit weight of the cross-linked amino acid-based resin, 1 ton / m
Water absorption capacity with a reversal of 0 to 7 times when a load of ² is applied. 23. An absorbent core (layer) comprising:
The sanitary article according to any one of claims 1 to 20, which has at least one of the water absorbing ability described in (H). (E) The absorption rate of absorbing 20 ml of artificial urine is 0.1
Water absorption capacity of ５０50 ml / sec · cm ² . (F) The saturated absorption amount when artificial urine is absorbed is 0.05
Water absorption capacity of ４4 g / cm ² . (G) Under the load of 20 g / cm ² , the amount of artificial urine absorbed
Water absorption capacity of 0.03 to 3 g / cm ² . (H) Saturated absorption when artificial urine is absorbed 1
The reversion when applying a load of ton / m ² is 0 to 7 g /
Water absorption capacity which is cm ² . 24. The absorbent core (layer) containing a crosslinked amino acid-based resin has at least one of the following water absorbing capacities (E ′) to (H ′). The sanitary article described in any one of the above. (E ′) a water absorption capacity in which the rate of absorbing artificial urine per unit weight of the crosslinked amino acid-based resin is 15 to 200 times per minute. (F ′) a water absorption capacity in which the saturated absorption amount when artificial urine is absorbed is 20 to 200 times per unit weight of the crosslinked amino acid-based resin. (G ′) 20 g per unit weight of crosslinked amino acid resin
Water absorption capacity under which the artificial urine absorption amount is 20 to 150 times under a load of / cm ² . (H ′) Water absorption capacity in which, when a load of 1 ton / m ² is applied to a saturated absorption of artificial urine per unit weight of the crosslinked amino acid-based resin, a return is 0 to 7 times.