TW202210600A - Sanitary article - Google Patents

Abstract

One aspect of the present invention pertains to a sanitary article in which a substrate is fixed by a hot-melt adhesive and which is characterized in that: the hot-melt adhesive is produced by a production method comprising introducing, during or after kneading of a liquid hot-melt adhesive material, at least 0.3 parts by mass of a fluid into a heating kneader with respect to 100 parts by mass of the hot-melt adhesive material, and degassing the mixture while heating and stirring or dispersing same so that the hot-melt adhesive material is brought into contact with the fluid; and the amount of residual octanal is at most 0.70 ppm or the amount of residual limonene is at most 0.060 ppm.

Description

hygiene products

The present invention relates to a sanitary article, in particular to a disposable sanitary article such as a disposable diaper, a sanitary article, and the like.

In the polymer materials used in hot melt adhesives used in various products, there are often traces of volatile organic compounds (hereinafter referred to as VOCs) such as raw materials or polymerization solvents remaining. These volatile organic compounds will evaporate or move from the cured adhesive, especially in the field of sanitary materials in recent years, the odor emitted when opening the sealed bag is often complained by consumers.

So far, as a disposable wearing article with reduced odor, there has been reported a packaging structure for the disposable wearing article, which is selected from the group consisting of ethylcyclohexane, toluene, ethylbenzene, m-xylene, and o-xylene. , styrene, α-methylstyrene, m-methylstyrene and p-methylstyrene of two or more volatile organic compounds, the concentration of the compound with the highest concentration is 400ppb or less (Patent Document 1) .

In the technique described in the above-mentioned patent document 1, the odor reduction of disposable wearing articles is achieved by using a low-odor hot-melt adhesive made of a low-VOC material.

However, in order to make a low-odor hot-melt adhesive, it is necessary to select a polymer material with less volatile components in the material. As a result, the design scope of the shrink-blending technology is limited, and the hot-melt adhesive with the adhesive performance requirements cannot be used. agent problem.

Furthermore, in the technique described in the above-mentioned Patent Document 1, reduction of ethylcyclohexane, toluene, ethylbenzene, m-xylene, o-xylene, styrene, α-methylstyrene and m-methylstyrene is described. and volatile organic compounds such as p-methylstyrene. However, according to the research of the inventors of the present application, it was found that the odor in sanitary products using a hot-melt adhesive (especially a rubber-based hot-melt adhesive) is most likely derived from octanal or limonene. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 2012-518063

[The problem to be solved by the invention]

The subject of the present invention is to solve the aforementioned problems. That is, the object of the present invention is to provide a hygienic product having a problem of adhesive odor (especially octanal odor or limonene odor), which is low in odor despite the use of a hot-melt adhesive exhibiting excellent adhesive performance. .

As a result of diligent studies to solve the above-mentioned problems, the inventors of the present application found that the above-mentioned objects can be achieved by the following constitutions, and based on this knowledge, the present invention was completed by repeating many studies.

That is, the sanitary article of one aspect of the present invention is a sanitary article in which a base material is fixed by a hot-melt adhesive, characterized in that the hot-melt adhesive is a hot-melt adhesive obtained by the following production method, and the remaining The amount of octanal is 0.70 ppm or less or the amount of residual limonene is 0.060 ppm or less; the method includes heating the kneader during or after kneading the liquid hot-melt adhesive material relative to the hot-melt adhesive. A fluid is introduced in an amount of 0.3 part by mass or more for 100 parts by mass of the material, and the material for hot melt adhesive is heated, stirred or dispersed so that the material for hot melt adhesive is in contact with the fluid, and degassing is performed.

[Form of implementing the invention]

The sanitary article base material of the present invention is fixed by a hot-melt adhesive. The hot-melt adhesive used for fixing the base material in the sanitary product of the present invention is a hot-melt adhesive obtained by the following production method as described above; the method is characterized by containing the liquid hot-melt adhesive material During or after kneading, a fluid is introduced into the heating kneader in an amount of 0.3 parts by mass or more relative to 100 parts by mass of the material for hot melt adhesive, and the material for hot melt adhesive is brought into contact with the fluid. heating and stirring, and degassing at the same time. The aforementioned hot-melt adhesive is characterized by maintaining excellent performance as an adhesive and having a low odor. Thereby, the residual octanal content of the sanitary product of the present invention is 0.70 ppm or less or the residual limonene content is 0.060 ppm or less, and the odor can be suppressed more than the sanitary product using the conventional hot-melt adhesive.

By adopting such a configuration, although the base material is fixed using a hot-melt adhesive exhibiting excellent adhesive properties, a sanitary article with low odor can be provided. Therefore, a hot-melt adhesive using a material containing a large amount of VOC or a material with a strong odor can be used to fix the substrate, and it is easier to take into account the adhesive performance in sanitary products, low VOC and low odor. In addition, since there is no need to use a special material, the degree of freedom of blending design can be improved, and the cost can be suppressed.

Embodiments of the present invention will be described in detail below, but the present invention is not limited to these.

First, the hot melt adhesive will be described. As the hot-melt adhesive material that can be used in the present embodiment, base resins, tackifiers, and other additives conventionally used for hot-melt adhesives can be used without particular limitation. In particular, according to the production method of the present embodiment, any hot-melt adhesive material used can provide a low-VOC and low-odor hot-melt adhesive.

As a specific material, as the base resin, for example, a thermoplastic polymer used as a component constituting a hot-melt adhesive can be used without particular limitation. The thermoplastic polymer specifically includes an elastomeric thermoplastic polymer, a polyolefin-based thermoplastic polymer, an ethylene vinyl acetate copolymer (EVA)-based thermoplastic polymer, a polyacrylate-based thermoplastic polymer, a polyester-based thermoplastic polymer, and a polyester-based thermoplastic polymer. Amide-based thermoplastic polymer.

The elastomeric thermoplastic polymer is not particularly limited as long as it is used as an elastomeric thermoplastic polymer in a hot-melt adhesive, and examples thereof include those having a structural unit (conjugated diene unit) based on a conjugated diene compound. Conjugated diene polymers of polymers, etc. Moreover, as an elastomer thermoplastic polymer, the thermoplastic block copolymer etc. of the copolymer of a conjugated diene type compound and a vinyl-type aromatic hydrocarbon are mentioned specifically. That is, as the aforementioned thermoplastic polymer, these thermoplastic block copolymers are preferably used.

The conjugated diene-based compound is not particularly limited as long as it is a diene compound having at least one pair of conjugated double bonds. Specific examples of the conjugated diene compound include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), and 2,3-dimethyl-1,3-butadiene. Diene, 1,3-pentadiene and 1,3-hexadiene, etc.

The vinyl-based aromatic hydrocarbon is not particularly limited as long as it is an aromatic hydrocarbon having a vinyl group. Specific examples of vinyl aromatic hydrocarbons include styrene, o-methylstyrene, p-methylstyrene, p-tert-butylstyrene, 1,3-dimethylstyrene, and α-methylbenzene Ethylene, vinyl naphthalene and vinyl anthracene, etc.

The conjugated diene-based polymer may be a hydrogenated conjugated diene-based copolymer or a non-hydrogenated non-hydrogenated conjugated two-based copolymer.

The thermoplastic polymer is preferably a thermoplastic block copolymer, and specific examples thereof include styrene-butadiene block copolymer, styrene-isoprene block copolymer, hydrogenated styrene-butadiene olefin block copolymers and hydrogenated styrene-isoprene block copolymers, etc. Also, these copolymers include ABA-type triblock copolymers. As a styrene-butadiene block copolymer, a styrene-butadiene-styrene block copolymer (SBS) etc. are mentioned, for example. Moreover, as a styrene-isoprene block copolymer, a styrene-isoprene-styrene block copolymer (SIS) etc. are mentioned, for example. Moreover, as a hydrogenated styrene-butadiene block copolymer, a styrene-ethylene-butylene-styrene block copolymer (SEBS) etc. are mentioned, for example. Moreover, as a hydrogenated styrene-isoprene block copolymer, a styrene-ethylene-propylene-styrene block copolymer (SEPS) etc. are mentioned, for example.

The polyolefin-based thermoplastic polymer is not particularly limited as long as it is used as a polyolefin-based thermoplastic polymer in a hot-melt adhesive. For example, polyolefin homopolymers and copolymers based on ethylene, propylene, and/or butylene are exemplified. Ethylene poly-alpha-olefin, atactic poly-alpha-olefin (APAO), and ethylene/alpha-olefin and propylene/alpha-olefin copolymers, etc.

The EVA-based thermoplastic polymer is not particularly limited as long as it is used as an EVA-based thermoplastic polymer in a hot-melt adhesive, and examples thereof include copolymers synthesized from ethylene and vinyl acetate.

The polyacrylate-based thermoplastic polymer is not particularly limited as long as it is used as a polyacrylate-based thermoplastic polymer in a hot-melt adhesive. When a polyacrylate-type thermoplastic polymer is mentioned, the block copolymer of polymethyl methacrylate and polybutyl acrylate, etc. are mentioned, for example.

The polyester-based thermoplastic polymer is not particularly limited as long as it is used as a polyester-based thermoplastic polymer in a hot-melt adhesive. As a polyester-type thermoplastic polymer, the polyester etc. which were polymerized using dimer acid are mentioned, for example.

The polyamide-based thermoplastic polymer is not particularly limited as long as it is used as a polyamide-based thermoplastic polymer in a hot-melt adhesive, and examples thereof include nylon and the like. The above-mentioned base resins may be used alone or in combination of two or more.

In addition, in this embodiment, a biomass type hot-melt adhesive can also be used. Biomass-based hot-melt adhesives refer to adhesives in which biomass-derived raw materials are incorporated, and examples thereof include adhesives incorporated in plant-derived resins such as turpentine.

Various materials have been mentioned above as the main components of the hot-melt adhesive of this embodiment, but especially in this embodiment, the odor of octanal and limonene can be suppressed. Therefore, as the adhesive, it is preferable to use workability, adhesive Rubber-based hot melt adhesive with excellent performance and economy. As the rubber-based hot-melt adhesive, among the above-mentioned hot-melt adhesives, for example, styrene-butadiene-styrene block copolymer (SBS) or styrene-isoprene-styrene block copolymer can be mentioned. A hot-melt adhesive whose main component is SIS (SIS) is a preferable example.

In addition, as for the adhesion-imparting agent, other aromatic, aliphatic, alicyclic, natural products, their hydrogenated products, and the like can also be used without particular limitation. For example, natural rosin, modified rosin, hydrogenated rosin, glycerol ester of natural rosin, glycerol ester of modified rosin, pentaerythritol ester of natural rosin, pentaerythritol ester of modified rosin, pentaerythritol ester of hydrogenated rosin, copolymerization of natural terpenes three-dimensional polymers of natural terpenes, hydrogenated derivatives of copolymers of hydrogenated terpenes, polyterpene resins, hydrogenated derivatives of phenolic modified terpene resins, aliphatic petroleum hydrocarbon resins, and aliphatic petroleum hydrocarbon resins Hydrogenated derivatives, aromatic petroleum hydrocarbon resins, hydrogenated derivatives of aromatic petroleum hydrocarbon resins, cyclic aliphatic petroleum hydrocarbon resins, hydrogenated derivatives of cyclic aliphatic petroleum hydrocarbon resins. The above-mentioned adhesion imparting agents may be used alone or in combination of two or more.

In addition, as additives, antioxidants, heat stabilizers, light stabilizers, ultraviolet absorbers, fillers, surfactants, coupling agents, colorants, antistatic agents, flame retardants, waxes, plasticizers, and the like can be used.

As an antioxidant, a phenolic antioxidant, an organic sulfur-type antioxidant, etc. are mentioned, for example. Phenolic antioxidants include, for example, 2,6-di-tert-butyl-4-methylphenol, n-octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl ) propionate, 2-tert-butyl-6-(3-tert-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, tetrakis[methylene-3- (3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane, etc. The organic sulfur-based antioxidants include, for example, dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3 '-thiodipropionate, pentaerythritol tetrakis (3-laurylthiopropionate), etc. As these antioxidants, the antioxidants exemplified above may be used alone, or two or more of them may be used in combination.

Plasticizers include, for example, mineral oils, synthetic oils, and vegetable oils.

Specific examples of the mineral oil include processing oils (paraffin-based processing oils, naphthenic-based processing oils, aromatic-based processing oils, and the like) and liquid paraffin. Specific examples of the paraffin-based processing oil include normal paraffins (butane, pentane, hexane, heptane, octane, nonane, decane, undecane, dodecane, tetradecane, pentadecane, etc.). , hexadecane, heptadecane, octadecane, nonadecane, eicosane, hexadecane, docosane, hexadecane, tetracosane, pentadecane, hexadecane , Heptadecane, Hexacosane, Nonacosane, Triacontane, Triacontane, Tricosane, Hexapentane, Hexacosane, Pentadecane, etc.); Isoparaffins (isoparaffins) Butane, isopentane, neopentane, isohexane, isopentane, neohexane, 2,3-dimethylbutane, methylhexanes, 3-ethylpentane, dimethylpentane , 2,2,3-trimethylbutane, 3-methylheptane, dimethylhexane, trimethylpentane, isononane, 2-methylnonane, isodecane, Isoundecane, Isododecane, Isotridecane, Isotetradecane, Isopentadecane, Isooctadecane, Isononadecane, Isoeicosane, 4-ethyl-5-methyloctane alkanes, etc.); derivatives of these saturated hydrocarbons, etc. As a specific example of the naphthenic-based processing oil, the naphthenic-based processing oil refers to the one with a higher number of naphthenic ring carbons among the processing oils. The naphthenic ring compound contained in the naphthenic processing oil includes a cyclic compound having 3 or more carbon atoms. More specific examples of the cycloalkane ring compound include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, and the like.

Specific examples of synthetic oils include ether oils, ester oils, phosphoric acid esters, and chlorinated olefins.

Specific examples of vegetable oils include olive oil, rice germ oil, corn oil, camellia oil, camellia oil, castor oil, jojoba seed oil, and eucalyptus oil.

The method for producing a hot-melt adhesive of the present embodiment includes the steps of introducing a fluid to a heating kneader during or after kneading a liquid material for a hot-melt adhesive, and heating, stirring or dispersing and removing The steps of air.

The inventors of the present application have unexpectedly found that the odor of octanal or limonene in sanitary products can be greatly reduced by using the hot-melt adhesive obtained through the aforementioned process (production method). The production method will be specifically described below.

If the step of introducing the fluid to the heating kneader is after the material for hot melt adhesive is put into the heating kneader, it may be performed during kneading of the material for hot melt adhesive, or may be performed after kneading is completed. It is preferably carried out after the mixing of the materials is completed. "Completion of kneading" in this embodiment means a state in which the materials of the hot-melt adhesive (for example, the base resin and the tackifier) exhibit the same fluidity.

About the heating kneading machine, a general manufacturing apparatus used for stirring and kneading a hot melt adhesive can be used. For example, in the general manufacturing method of hot melt adhesive, there are continuous processing method and batch processing method. As the heating kneader used in the continuous processing method, a Ruder, an extruder, a biaxial conical screw, or the like can be used. In addition, as the heating kneader used in the batch processing method, a stirring kneader, a Banbury kneader, a kneader, or the like can be used.

The fluid introduced into the heating kneader is not particularly limited, and its form may be liquid or gas, and may be in a supercritical state or a subcritical state. Specifically, nitrogen gas, oxygen gas, argon gas, helium gas, carbon dioxide gas, carbon monoxide gas, ammonia gas, air, liquefied nitrogen, liquefied helium, liquefied carbon dioxide, liquefied argon, liquefied oxygen, methanol, ethanol, 1-propanol, Isopropanol, 2-butanol, n-hexane, diethyl ether, ethyl acetate, acetone, methyl ethyl ketone, tetrahydrofuran, limonene, aliphatic solvents, water and other fluids with a viscosity of 10 mPa·s or less. These may be used individually by 1 type, respectively, and may be used in combination of 2 or more types.

The introduction of the fluid into the heating kneader was performed in an amount of 0.3 part by mass with respect to 100 parts by mass of the material for the hot melt adhesive. If the introduction amount is less than 0.3 part by mass, the removal efficiency of the VOC component may be reduced.

In addition, the upper limit of the introduction amount does not need to be set in particular, since the effect of VOC removal and deodorization will not be lowered. However, in consideration of cost, process time, and the like, it is preferably 50 parts by mass or less, and more preferably 25 parts by mass or less, with respect to 100 parts by mass of the material for a hot-melt adhesive.

The method of introducing the fluid in the present embodiment is not particularly limited, and the fluid may be introduced from any of the upper, side, and lower sides of the heating kneader. Specifically, for example, if the aforementioned fluid is a gas or a liquid, it can be introduced from below and/or the side of the heating kneader.

After the above-mentioned fluid is introduced into the heating kneader, the material for hot-melt adhesive is heated, stirred or dispersed so that the material for hot-melt adhesive is in contact with the above-mentioned fluid, and degassing is carried out at the same time. The heating temperature at this time is not particularly limited as long as it is equal to or higher than the melting temperature of the material for the hot-melt adhesive, and can be appropriately set according to the type of the base resin used as the material for the hot-melt adhesive.

Heating stirring or dispersion can be carried out by means conventionally known in the art. For example, paddle, vortex, propeller, anchor, propeller, Maxblender, Fullzone, screw, blender, MR-205, Hi-F mixer, Sanmer, etc. can be used. These may be used individually by 1 type, respectively, and may be used in combination of 2 or more types.

Degassing is preferably carried out at a fractional exhaust velocity that is equal to or greater than 0.4 times the volume of the heating and kneading machine until the gauge pressure becomes a vacuum higher than -60 kPa. By degassing under these conditions, the amount of residual VOC, especially the amount of residual octanal or the amount of residual limonene, can be suppressed more reliably.

The degassing means of the present embodiment is not particularly limited. Specifically, for example, a vacuum pump adjusted to the above-described minute-speed exhaust speed can be used to depressurize to the above-described degree of vacuum to degas.

It is more preferable that the above-mentioned minute-speed exhaust velocity is equal to or more than the volume of the heating kneader. The upper limit of the minute exhaust velocity is not necessarily limited, but from the viewpoints of increasing the size of the facility and reducing the cost, it is preferably 17.5 times or less the volume of the heating kneader.

The aforementioned degassing is more preferably a vacuum with a gauge pressure higher than -90 kPa. There is no need to set an upper limit in particular, but from the viewpoints of equipment damage, enlargement of equipment, and increase in cost, it is preferable that the gauge pressure is lower than -101kPa vacuum.

As described above, by dispersing the fluid in the material for hot-melt adhesive under specific conditions, so that the less volatile organic compounds are adsorbed on the fluid, it is determined that the material for hot-melt adhesive can be removed from the material for hot-melt adhesive by the degassing step. remove. As a result, a low-VOC and low-odor hot-melt adhesive can be provided.

Furthermore, the production method of the present embodiment may include a step of cooling and condensing the exhaust gas discharged from the heating kneader, and recovering the fluid containing the volatile organic compound.

Thereby, there are further advantages such as realizing a longer life of the vacuum pump.

In addition, the fluid recovery rate in the aforementioned recovery step is preferably 60% or more. In this way, the research and judgment can further suppress the environmental air pollution.

Since the hot-melt adhesive obtained by the manufacturing method of this embodiment has few residual volatile organic compounds, and has low VOC and low odor, it is extremely useful in industrial application. These hot-melt adhesives are characterized by less residual volatile organic compounds (octaldehyde or limonene) than conventional hot-melt adhesives produced by selecting polymer materials containing less volatile components in the material.

The sanitary products of the present embodiment include disposable diapers, sanitary products such as sanitary napkins, breast milk cotton pads, pet pads, hospital gowns, surgical gowns, and other products.

Hereinafter, as specific examples of the sanitary article, wearing sanitary articles such as disposable diapers and sanitary articles (sanitary napkins) will be described, but the present invention is not limited to these embodiments.

The constituent members of the sanitary ware for wearing in the present embodiment can be used without any particular limitation and are conventionally used for sanitary ware for wear.

As the base material used for the aforementioned sanitary products, those conventionally used for sanitary products such as disposable diapers and sanitary products can be used without particular limitation, for example, paper base materials, various non-woven fabrics, resin films, woven fabrics, resins, Rubber, etc., are appropriately selected according to the type of hygiene products.

Specifically, for example, it can be a laminate composed of multiple layers. The surface sheet in contact with the wearer's skin can be made of non-woven fabric or woven fabric, and the back sheet can be made of resin film or paper base. A liquid-retaining absorber is provided between the surface sheet and the back sheet. The absorbent body may comprise superabsorbent polymers such as hydrogel materials that can absorb and retain moisture, and the like. These constituent members are laminated and fixed with the above-mentioned hot-melt adhesive; some parts may be further fixed by joining means other than the above-mentioned hot-melt adhesive (such as heat sealing, ultrasonic welding, etc.) part.

The shape of the wearing sanitary article of the present embodiment is worn around the waist or crotch of the wearer. Therefore, in the case of a disposable diaper, the wearing state is usually in the shape of shorts; in the case of a sanitary napkin, etc. , it is a vertically elongated flake.

Furthermore, in the case of a disposable wearing hygiene product, the above-mentioned wearing hygiene product may be further packaged by a packaging material from the viewpoint of hygiene. The packaging material can be composed of various resin films and the like, and a tear line for easy opening may be provided. In the sanitary product of the present embodiment, since the odor caused by the hot-melt adhesive can be suppressed, the odor generated when the package is opened for a long time can be reduced even if the sanitary product is covered with the aforementioned packaging material for a long time.

The sanitary article of the present embodiment as described above has extremely little odor because the residual octanal content is 0.70 ppm or less or the residual limonene content is 0.060 ppm or less, and is particularly useful as a disposable sanitary article. The aforementioned residual octanal amount and residual limonene amount referred to in the present embodiment refer to the values measured by the methods described in the following examples.

Moreover, in the sanitary article of this embodiment, the more preferable residual amount of octanal is 0.68 ppm or less, and the more preferable residual amount of limonene is 0.050 ppm or less. Still more preferable residual octanal content is 0.58 ppm or less, and still more preferable residual limonene content is 0.045 ppm or less.

The present specification has disclosed various aspects of the technology as described above, and the main technology among them is summarized below.

That is, the sanitary article of one aspect of the present invention is a sanitary article in which a base material is fixed by a hot-melt adhesive, characterized in that the hot-melt adhesive is a hot-melt adhesive obtained by the following production method, and the residual caustic The amount of aldehyde is 0.70 ppm or less or the amount of residual limonene is 0.060 ppm or less; the method includes heating the kneading machine during or after kneading the liquid hot-melt adhesive material. 100 parts by mass of the material is introduced into the fluid in an amount of 0.3 part by mass or more, and the material for hot melt adhesive is heated, stirred or dispersed so that the material for hot melt adhesive is in contact with the fluid, and degassed.

According to the above-mentioned constitution, it is possible to provide a hygienic product with low odor despite the use of a hot-melt adhesive exhibiting excellent adhesive performance.

In the aforementioned sanitary product, the aforementioned substrate is preferably at least one selected from the group consisting of paper, non-woven fabric, resin film, woven fabric, resin, and rubber.

Furthermore, the aforementioned hot-melt adhesive is preferably a rubber-based hot-melt adhesive. Thereby, there are advantages of being excellent in workability, adhesiveness, economical efficiency, and the like. [Example]

The following describes the embodiments of the present invention, but the present invention is not limited to them.

First, the material for hot-melt adhesives used in this example is shown below.

・Hot-melt adhesive 1 (rubber-based hot-melt adhesive 1): "MORESCO-MELT (registered trademark) TN-287Z", softening point 89°C, viscosity 3900mPa·s at 160°C ・Hot-melt adhesive 2 (rubber-based hot-melt adhesive 2): "MORESCO-MELT (registered trademark) TN-286Z", softening point 97°C, viscosity 4900mPa·s at 160°C ・Hot Melt Adhesive 3 (Rubber-based Hot Melt Adhesive 3): "MORESCO-MELT (registered trademark) TN-269Z", softening point 83°C, viscosity 2100mPa·s at 160°C ・Hot-melt adhesive 4 (rubber-based hot-melt adhesive 4): "MORESCO-MELT (registered trademark) TN-202Z", softening point 83°C, viscosity 490mPa·s at 160°C ・Hot melt adhesive 5 (rubber-based hot melt adhesive 5): "MORESCO-MELT (registered trademark) TN-213Z", softening point 94°C, viscosity 6400mPa·s at 160°C ・Hot melt adhesive 6 (biomass based hot melt adhesive): "MORESCO-MELT (registered trademark) BM-546Z", softening point 94°C, viscosity 4000mPa·s at 160°C

(Manufacturing method A of hot melt adhesive) 2 kg of hot-melt adhesive material or hot-melt adhesive 2 material was put into a stainless steel (SUS) stirring kneader with a capacity of 4 L, and it was stirred and melted above the melting point of each hot-melt adhesive.

Then, 0.3 part by mass or more of isopropyl alcohol is introduced from the side surface or/and below of the above-mentioned stirrer with respect to 100 parts by mass of the material for hot melt adhesive. The hot-melt adhesive was obtained by degassing at a minute rate exhaust rate (exhaust rate/storage tank volume) of 0.45 times or more the volume of the kneader until the gauge pressure of the kneader became -90kPa.

(Manufacturing method B of hot melt adhesive) A material of 2 kg of hot-melt adhesive was put into a stirring kneader made of stainless steel (SUS) with a capacity of 4 L, and it was stirred and melted at a temperature above the melting point of each hot-melt adhesive.

Then, 13.0 parts by mass or more of isopropyl alcohol is introduced from the side surface or/and below of the kneader with respect to 100 parts by mass of the material for hot melt adhesive. The hot-melt adhesive was obtained by degassing at a minute rate exhaust rate (exhaust rate/storage tank volume) of 0.45 times or more the volume of the kneader until the gauge pressure of the kneader became -98kPa.

(Manufacturing method C of hot melt adhesive) A material of 2 kg of hot-melt adhesive was put into a stirring kneader made of stainless steel (SUS) with a capacity of 4 L, and it was stirred and melted at a temperature above the melting point of each hot-melt adhesive.

After that, 10.0 parts by mass or more of distilled water was introduced from the side surface or/and below of the kneader with respect to 100 parts by mass of the material for hot melt adhesive. The hot-melt adhesive was obtained by degassing at a minute rate exhaust rate (exhaust rate/storage tank volume) of 0.40 times or more the volume of the kneader until the gauge pressure of the kneader became -60kPa.

(Preparation of Samples for Examples and Comparative Examples) First, the substrate system prepares the following: ・Facial paper ・Non-woven fabric 1: point-bonded non-woven fabric (unit weight 13gsm) ・Non-woven fabric 2: point-bonded non-woven fabric (unit weight 15gsm) ・Breathable 1: Breathable non-woven fabric (unit weight 8gsm) ・Breathable 2: Breathable non-woven fabric (unit weight 10gsm) ・Polyethylene sheet 1: Breathable polyethylene sheet ・Polyethylene sheet 2: Non-breathable polyethylene sheet

By heating the hot-melt adhesives produced by the methods A to C shown in Tables 1 to 3 (in Comparative Examples 1 to 4, the hot-melt adhesives shown in Table 1 were used without processing) to 160° C. be melted. The molten hot-melt adhesive was applied on one side of the adherends shown in Tables 1 to 3 below at 10 gsm (g/m ² ) using an applicator. After 1 second after coating, place another adherend on the adherend coated with the hot-melt adhesive by contacting the hot-melt adhesive, and press 0.01 at a pressure of 50gf/ ^cm2 at 23°C Second. This laminate was used as a sample (sample) for the following evaluation test.

[Evaluation Test 1: Measurement of Residual Limonene and Residual n-Octanol (Octanol) Amounts] The amounts of limonene and n-octaldehyde were measured using a gas chromatography mass spectrometer (GC Agilent 7890B GC system, MS Agilent 5977B series GC/MSD system, DHS GERSTEL DHS system) based on dynamic headspace injection analysis method. As a pretreatment, each sample was heated at 160° C. for 60 minutes. The capillary column was made of 0.25 mm inner diameter, 5% phenyl/95% dimethylpolysiloxane coating (coating thickness 0.25 μm), and 30 m in length. The heating program of the column was heated from 40 to 300°C at 10°C/min and held for 15 minutes thereafter. In this way, limonene and n-octaldehyde detected by mass spectrometer were quantified by calibration curve.

[Evaluation Test 2: Sensory Evaluation of Odor] The sample bonded with the hot-melt adhesive was placed in a 5-L sampling bag (packaging material) in a size of 5 m ² . The sample was heated at 80° C. for 30 minutes, and after being allowed to stand at room temperature for 10 minutes, the smell at the time of opening was smelled.

The evaluation criteria for the above functional tests are as follows: ・Limonene Odor Evaluation Criteria ◎: No smell (<0.039ppm) ○: Smell only slightly (0.039~0.060ppm) ×: Strong odor (>0.060ppm) In addition, in Tables 1 to 3, "ND" means that the remaining amount is below the detection limit. ・Standard for the evaluation of octanal odor ◎: No smell (<0.31ppm) ○: Smell only slightly (0.31~0.70ppm) ×: Strong odor (>0.70ppm) In addition, in Tables 1 to 3, "<0.02" means that the residual amount is less than 0.02 ppb (the detection limit or less).

[Evaluation Test 3: Peeling Test] After leaving each sample at 25° C. for 24 hours, one of the adherends in the sample was peeled off by hand, and the destruction state of the adherend was confirmed. In addition, the material destruction of the adherend refers to a state in which a part of the surfaces of the two adherends that adhere to each other is damaged. The evaluation system performed the experiment in triplicate. ・Peeling evaluation criteria (among 3 samples) ◎: All materials destroyed ○: 1~2 materials destroyed ×: None of the materials are damaged

The results are shown in Tables 1 to 3.

(inspection) As can be seen from the results in Tables 1 to 3, for the relevant samples of the present invention (Examples 1 to 15), regardless of the type of substrate, the amount of octanal was below 0.70 ppm, or the amount of limonene was all below 0.060 ppm, and the odor was also somewhat reduced. Also from the results of the peeling test, it was also confirmed that the substrate was firmly fixed (bonded).

On the other hand, the samples of Comparative Example 1 and Comparative Example 2 obtained by directly using a commercially available hot-melt adhesive had a large amount of residual octanal or residual limonene, and smelled bad. Furthermore, the samples of Comparative Example 3 and Comparative Example 4, which were used without processing, although the same hot-melt adhesive as in the Example was used, also showed that the residual octanal amount or residual limonene amount of the sample was large. , and smell the odor.

This application is based on Japanese Patent Application No. 2020-093917 filed on May 29, 2020, the contents of which are incorporated herein.

In order to express the present invention, the present invention has been appropriately and fully described with reference to specific examples and the like in the foregoing description, but those skilled in the art will recognize that the foregoing embodiments can be easily modified and/or improved. Therefore, as long as the modified form or improved form implemented by those skilled in the art does not deviate from the scope of the claims recorded in the scope of the patent application, the modified form or the modified form should be construed as being included in the scope of the patent scope of the application. [Industrial availability]

The present invention has wide industrial applicability in the technical field related to sanitary products using hot-melt adhesives.

Claims (3)

A sanitary product, which is a sanitary product with a base material fixed by a hot-melt adhesive, characterized in that: The aforementioned hot-melt adhesive is a hot-melt adhesive obtained by the following production method, and the residual octanal content is 0.70 ppm or less or the residual limonene content is 0.060 ppm or less; The method includes introducing a fluid into a heating kneader in an amount of 0.3 parts by mass or more with respect to 100 parts by mass of the material for hot melt adhesives during or after kneading the liquid material for hot melt adhesives, and Degassing is performed while heating, stirring or dispersing so that the material for a hot melt adhesive is brought into contact with the fluid. The sanitary article according to claim 1, wherein the substrate is at least one selected from the group consisting of paper, non-woven fabric, resin film, woven fabric, resin and rubber. The sanitary article according to claim 1 or 2, wherein the hot-melt adhesive is a rubber-based hot-melt adhesive.