WO2023127235A1 - Temperature indicating material-containing adhesive composition and skin-patch thermometer using same - Google Patents

Abstract

The purpose of the present invention is to provide: a skin-patch thermometer which is not susceptible to the ambient temperature and has properties that are suitable for attachment to the skin; and a temperature indicating material-containing adhesive composition which is used for this skin-patch thermometer. The present invention provides a temperature indicating material-containing adhesive composition that contains an adhesive and a temperature indicating material, the color of which changes according to the temperature, wherein the adhesive contains 6.5% by weight to 69.0% by weight of a thermoplastic elastomer that has an (A)-(B)-(A') triblock structure relative to the total amount of the temperature indicating material-containing adhesive composition.

Description

Adhesive composition containing temperature indicating material and thermometer attached to skin using the same

The present invention relates to a temperature indicating material-containing pressure-sensitive adhesive composition and a skin-adhered thermometer using the same.

As a measure to prevent infection with the new coronavirus, there is an increasing need for products that can easily measure a person's body temperature by attaching it directly to the skin. Conventionally, on the surface of a base material made of polypropylene film, a temperature measurement part formed by printing a reversible thermochromic material layer and an irreversible thermochromic material layer is provided, and an adhesive layer formed on the back surface of the base material is used. 2. Description of the Related Art There is known a thermometer for measuring skin epidermal temperature, which is attached to the skin (see, for example, Patent Document 1).

In addition, although not for measuring body temperature, there are known labels for grasping the temperature state of perishable foods, etc. that contain a discoloring material that changes color according to temperature (see, for example, Patent Document 2).

Japanese Unexamined Patent Publication "JP-A-7-103829" Japanese Patent Publication "JP 2020-146951"

However, the prior art as described above has room for improvement from the standpoint of providing a skin-adhered thermometer that is less susceptible to environmental temperature and has performance suitable for being applied to the skin.

For example, the thermometer disclosed in Patent Document 1 is easily affected by the environmental temperature because the surface of the substrate that is in contact with the surrounding environment is coated with ink that changes color at a constant temperature. Therefore, there is a large deviation from the actual body temperature, and there is a problem that the responsiveness to changes in skin temperature is poor.

One aspect of the present invention is to provide a skin-adhered thermometer that is less susceptible to environmental temperature and has performance suitable for being applied to the skin, and a temperature-indicating material-containing pressure-sensitive adhesive composition used in such a skin-adhered thermometer. aim.

In order to solve the above problems, a pressure-sensitive adhesive composition according to one aspect of the present invention is a temperature-indicating material-containing pressure-sensitive adhesive composition containing a temperature-indicating material that changes color depending on temperature and a pressure-sensitive adhesive, wherein the pressure-sensitive adhesive contains a thermoplastic elastomer having a (A)-(B)-(A') triblock structure in an amount of 6.5% to 69.0% by weight with respect to the total amount of the pressure-sensitive adhesive composition containing a temperature indicating material.

According to one aspect of the present invention, there is provided a skin-adhered thermometer that is hardly affected by environmental temperature and has performance suitable for being applied to the skin, and a temperature-indicating material-containing pressure-sensitive adhesive composition used in such a skin-adhered thermometer. can do.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to this, and various modifications are possible within the scope described, and the present invention also includes embodiments obtained by appropriately combining technical means disclosed in different embodiments. included in the technical scope of In this specification, unless otherwise specified, "A to B" representing a numerical range means "A or more and B or less".

[1. Adhesive composition containing temperature indicating material]
The inventors of the present invention conducted studies to solve the above problems, and found that a pressure-sensitive adhesive containing a thermoplastic elastomer having a (A)-(B)-(A') triblock structure in a predetermined proportion, and a temperature A pressure-sensitive adhesive layer is formed using a temperature-indicating material-containing pressure-sensitive adhesive composition containing a temperature-indicating material that changes color depending on the temperature, and the pressure-sensitive adhesive layer and the base layer are laminated to form a skin-adhered thermometer. Furthermore, it is possible to realize a skin-adhered thermometer having performance suitable for being adhered to the skin, which has excellent adhesion to the skin, does not leave adhesive residue when peeled off, and has completed the present invention. Arrived.

That is, the temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention is a temperature indicating material-containing pressure-sensitive adhesive composition containing a temperature indicating material that changes color according to temperature and an adhesive, wherein the pressure-sensitive adhesive is ( A)-(B)-(A') A thermoplastic elastomer having a triblock structure is contained in an amount of 6.5% to 69.0% by weight based on the total amount of the pressure-sensitive adhesive composition containing a temperature indicating material.

[1.1. Adhesive]
A temperature indicating material-containing adhesive composition according to one embodiment of the present invention includes a temperature indicating material and an adhesive. Here, as used herein, the term "adhesive" includes at least a base polymer and, if necessary, a tackifying resin, a softening agent, a liquid polymer, a coloring agent, an antioxidant, a stabilizer, a filler, an interface Materials or compositions containing active agents, antistatic agents, flame retardants, waxes, antimicrobial agents, and fragrances are contemplated.

<1.1.1. (A)-(B)-(A') Thermoplastic elastomer having a triblock structure>
In the present invention, the pressure-sensitive adhesive contains a thermoplastic elastomer having a (A)-(B)-(A') triblock structure in an amount of 6.5% by weight to 69% by weight based on the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition. Contains 0% by weight. Here, in the present specification, the term "thermoplastic elastomer" means a polymeric substance that undergoes plastic deformation when heated and exhibits elasticity at room temperature. Said thermoplastic elastomers are included as base polymers. Examples of the thermoplastic elastomer include acrylic thermoplastic elastomers, styrene thermoplastic elastomers, and the like.

The adhesive contains a thermoplastic elastomer having a (A)-(B)-(A') triblock structure. Here, the blocks (A) and (A′) refer to polymer blocks having a glass transition temperature higher than 40° C. (hereinafter in this specification, polymer blocks having a glass transition temperature higher than 40° C. are referred to as “hard blocks”). and the block (B) is a polymer block having a glass transition temperature lower than 20°C (hereinafter, in this specification, a polymer block having a glass transition temperature lower than 20°C is referred to as a "soft block ”). As used herein, the glass transition temperature represents the extrapolation start temperature of the curve obtained by DSC measurement.

The lower limits of the glass transition temperatures of the blocks (A) and (A') are each preferably 60°C or higher, more preferably 70°C or higher, and even more preferably 80°C or higher. The upper limits of the glass transition temperatures of the blocks (A) and (A') are each preferably 140°C or lower, more preferably 130°C or lower, and even more preferably 120°C or lower. When the glass transition temperature is within this range, the blocks (A) and (A') act as physical pseudo cross-linking points. Therefore, the adhesive properties, durability and heat resistance of the adhesive can be improved.

The lower limit of the glass transition temperature of the block (B) is preferably -100°C or higher, more preferably -80°C or higher, and even more preferably -60°C or higher. The upper limit of the glass transition temperature of the block (B) is preferably 0° C. or lower, more preferably -20° C. or lower, and even more preferably -40° C. or lower. When the glass transition temperature is within this range, a pressure-sensitive adhesive having excellent tack and adhesion can be obtained.

The blocks (A) and (A') may be the same polymer block or different polymer blocks as long as they have a glass transition temperature within the above range.

In one embodiment of the present invention, the pressure-sensitive adhesive is a thermoplastic elastomer having a (A)-(B)-(A') triblock structure, and the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition is 6.5%. % to 69.0% by weight. The lower limit of the content of the thermoplastic elastomer having a triblock structure may be 6.5% by weight, more preferably 7.0% by weight or more, and still more preferably 8.0% by weight or more. . The upper limit of the content of the thermoplastic elastomer having the triblock structure may be 69.0% by weight, more preferably 65.0% by weight or less, still more preferably 60% by weight or less. By containing 6.5% by weight or more of the thermoplastic elastomer having the triblock structure, it is possible to realize a pressure-sensitive adhesive layer with reduced adhesive residue when the pressure-sensitive adhesive layer is peeled off from the skin. Further, if the content of the thermoplastic elastomer having a triblock structure is 69.0% by weight or less with respect to the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition, a pressure-sensitive adhesive layer with excellent adhesion to the skin is formed. can be realized.

Here, the content of the (A)-(B)-(A') thermoplastic elastomer having a triblock structure relative to the total amount of the pressure-sensitive adhesive composition containing the temperature indicating material can be measured by gel permeation chromatography (GPC). can. Refractive index (RI) detectors and photodiode array (PDA)/UV detectors can be used as detectors. Specifically, the pressure-sensitive adhesive composition containing the temperature indicating material is subjected to GPC measurement, and the compounding ratio of each component is determined from the peak area ratio. By this method, when the high-molecular-weight component is a block copolymer, the ratio of the high-molecular compound having a triblock structure and the high-molecular compound having a diblock structure can also be confirmed. A PDA/UV detector is used to check which component each peak belongs to.

(Acrylic thermoplastic elastomer)
In one embodiment of the present invention, the thermoplastic elastomer having the (A)-(B)-(A') triblock structure may be an acrylic thermoplastic elastomer. A thermoplastic acrylic elastomer is preferable as a component of the pressure-sensitive adhesive in one embodiment of the present invention because it has superior moisture permeability compared to other base polymers.

At this time, the blocks (A) and (A') are not particularly limited as long as they are polymer blocks having a glass transition temperature within the above range. In both the blocks (A) and (A′), the lower limit of the weight occupied by the methacrylic acid ester units among the repeating units constituting the blocks (A) and (A′) is the total weight of the block. 60% by weight or more is preferable, 80% by weight or more is more preferable, 90% by weight or more is still more preferable, and 95% by weight or more is particularly preferable. In both blocks (A) and (A'), the upper limit of the weight occupied by the methacrylate units may be 100% by weight or less of the total weight of the block.

Examples of methacrylic acid esters that can be constituent units of the blocks (A) and (A') include methacrylic acid esters having no functional group (e.g., methyl methacrylate, ethyl methacrylate, propyl methacrylate, methacrylic butyl acid, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, isobornyl methacrylate, phenyl methacrylate, benzyl methacrylate, etc.); A methacrylate ester having a mentioned. Ester (COOR) of methacrylic acid ester (CH ₂ ═C(CH ₃ )—COOR: R is an organic group) may have a branched structure and a cyclic structure.

Among these, from the viewpoint of improving the heat resistance and durability of the adhesive, methacrylic acid esters having no functional group are more preferable, such as methyl methacrylate, ethyl methacrylate, tert-butyl methacrylate, and cyclohexyl methacrylate. , isobornyl methacrylate and phenyl methacrylate are preferred. Methyl methacrylate is more preferable from the viewpoint of clarity of phase separation between the blocks (A) and (A') and the block (B) and improvement of cohesion.

The blocks (A) and (A') may contain only one type or two or more types of the methacrylic acid esters described above. Also, the monomer compositions of the blocks (A) and (A') may be the same or different. Furthermore, the stereoregularities of the methacrylate units contained in the blocks (A) and (A') may be the same or different.

In the acrylic thermoplastic elastomer having the (A)-(B)-(A') triblock structure, the lower limit of the total content of the blocks (A) and (A') is preferably 5% by weight or more, 7% by weight or more is more preferable, and 10% by weight or more is even more preferable. The upper limit of the total content of the blocks (A) and (A') is preferably 30% by weight or less, more preferably 27% by weight or less, and even more preferably 25% by weight or less. When the total content of the blocks (A) and (A') is within the above range, it is possible to form a pressure-sensitive adhesive layer that has excellent adhesion to the skin and leaves little adhesive residue when peeled off.

In the acrylic thermoplastic elastomer having the (A)-(B)-(A') triblock structure, the lower limit of the weight average molecular weight of each of the blocks (A) and (A') is preferably 1,000 or more. , 2,000 or more. The upper limit of the weight average molecular weight of each of the blocks (A) and (A') is preferably 30,000 or less, more preferably 25,500 or less. If the weight-average molecular weights of the blocks (A) and (A') are within the above range, the melt viscosity of the hot-melt pressure-sensitive adhesive can be adjusted within an appropriate range. Furthermore, when the adhesive is prepared, it is possible to form an adhesive layer that has excellent adhesion to the skin and leaves little adhesive residue when peeled off. In addition, in this specification, a "weight average molecular weight" means the value converted into polystyrene by a gel permeation chromatography (GPC).

The block (B) is not particularly limited as long as it is a polymer block having a glass transition temperature within the above range. Among the repeating units constituting the block (B), the lower limit of the weight occupied by the acrylic acid ester unit is preferably 60% by weight or more, more preferably 80% by weight or more, more preferably 90% by weight of the total weight of the block (B). % or more is more preferable, and 95% by weight or more is particularly preferable. The upper limit of the weight of the acrylate units in the block (B) may be 100% by weight of the total weight of the block (B).

The block (B) is, for example, an acrylic ester having no functional group (e.g., methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, amyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, , octyl acrylate, decyl acrylate, bornyl acrylate, lauryl acrylate, octadecyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, etc.); ethyl, ethoxyethyl acrylate, 2-hydroxyethyl acrylate, 2-aminoethyl acrylate, glycidyl acrylate, tetrahydrofurfuryl acrylate, diethylaminoethyl acrylate, phenoxyethyl acrylate, etc.). Ester (COOR) of acrylic acid ester (CH ₂ ═CH—COOR: R is an organic group) may have a branched structure and a cyclic structure.

Among these, from the viewpoint of improving transparency and flexibility, the block (B) has the formula "CH ₂ =CH-COOR ¹ (wherein R ¹ represents a hydrocarbon group having 1 to 10 carbon atoms)". It is preferably a block synthesized from an acrylate monomer represented by. From the viewpoint of clarity of phase separation between the blocks (A) and (A') and the block (B) and improvement of the cohesive force, an acrylic acid ester having no functional group (e.g., methyl acrylate, acrylic acid Ethyl, isopropyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert-butyl acrylate, amyl acrylate, isoamyl acrylate, n-hexyl acrylate, acrylic acid 2-ethylhexyl, n-octyl acrylate, isooctyl acrylate, decyl acrylate, isobornyl acrylate, cyclohexyl acrylate, phenyl acrylate, benzyl acrylate, etc.) are more preferred. Furthermore, from the viewpoint of adhesiveness and stable adhesive strength at room temperature, it is preferable to select one or more from methyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate and isooctyl acrylate. More preferably, one or more of n-butyl acrylate and 2-ethylhexyl acrylate are selected.

The block (B) may contain only one type of the acrylic acid esters described above, or may contain two or more types.

In the acrylic thermoplastic elastomer having the (A)-(B)-(A′) triblock structure, the lower limit of the content of the block (B) is preferably 70% by weight or more, more preferably 73% by weight or more. Preferably, 75% by weight or more is more preferable. The upper limit of the content of the block (B) is preferably 95% by weight or less, more preferably 93% by weight or less, and even more preferably 90% by weight or less. When the content of the block (B) is within the above range, it is possible to form a pressure-sensitive adhesive layer that has excellent adhesion to the skin and leaves little adhesive residue when peeled off.

In the (A)-(B)-(A′) acrylic thermoplastic elastomer having a triblock structure, the lower limit of the weight average molecular weight of the block (B) is preferably 45,000 or more, more preferably 50,000 or more. more preferred. The upper limit of the weight average molecular weight of the block (B) is preferably 270,000 or less, more preferably 250,000 or less. If the weight average molecular weight of the block (B) is within the above range, the melt viscosity of the hot-melt pressure-sensitive adhesive can be adjusted within an appropriate range. In addition, when the adhesive is adjusted, it is possible to form an adhesive layer that is excellent in adhesion to the skin and leaves little adhesive residue when peeled off.

The acrylic thermoplastic elastomer having a triblock structure is not particularly limited as long as it is a polymer of any combination of the blocks (A), (B), and (A'), but a more preferable example is is, for example, (methyl methacrylate)-(n-butyl acrylate)-(methyl methacrylate) block copolymer, (methyl methacrylate)-(n-butyl acrylate/2-ethylhexyl acrylate)-(methacryl acid methyl) block copolymers, and the like.

The lower limit of the weight average molecular weight of the acrylic thermoplastic elastomer having the triblock structure is preferably 50,000 or more, more preferably 55,000 or more, and even more preferably 60,000 or more. The upper limit of the weight average molecular weight of the thermoplastic acrylic elastomer having a triblock structure is preferably 300,000 or less, more preferably 270,000 or less, and even more preferably 250,000 or less. When the weight-average molecular weight is within the above range, the melt viscosity of the pressure-sensitive adhesive is lowered and the pressure-sensitive adhesive layer is easily formed.

The lower limit of the molecular weight distribution (Mw/Mn) of the acrylic thermoplastic elastomer having the triblock structure is 1.0, and the upper limit of the molecular weight distribution (Mw/Mn) is preferably 1.5 or less, and 1.4. The following are more preferred. As used herein, the weight average molecular weight (Mw) and the number average molecular weight (Mn) are the weight average molecular weight and number average molecular weight in terms of standard polystyrene determined by gel permeation chromatography (GPC).

In one embodiment of the present invention, the pressure-sensitive adhesive may contain at least one acrylic thermoplastic elastomer having the (A)-(B)-(A') triblock structure, and the (A) -(B)-(A') Two or more types of acrylic thermoplastic elastomers having a triblock structure may be included.

The acrylic thermoplastic elastomer having the triblock structure can be produced by a known method. Also, commercially available products having the properties described above can be suitably used.

(Styrene-based thermoplastic elastomer)
In one embodiment of the present invention, the thermoplastic elastomer having the (A)-(B)-(A') triblock structure may be a styrenic thermoplastic elastomer. A styrene-based thermoplastic elastomer is softer than other base polymers, has good compatibility with tackifying resins and softening agents, and is easy to adjust adhesive physical properties. is preferred as

At this time, the blocks (A) and (A') are not particularly limited as long as they are polymer blocks having a glass transition temperature within the above range. In both the blocks (A) and (A'), the lower limit of the weight occupied by the styrene units among the repeating units constituting the blocks (A) and (A') is 60% of the total weight of the block. % by weight or more is preferable, 80% by weight or more is more preferable, 90% by weight or more is still more preferable, and 95% by weight or more is particularly preferable. The upper limit of the weight of styrene units in both blocks (A) and (A') may be 100% by weight or less of the total weight of the block.

Examples of styrenic monomers that can be constituent units of the blocks (A) and (A′) include styrene, α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, ethyl Styrene, p-tert-butylstyrene, 1,3-dimethylstyrene, and the like.

Among these, styrene is more preferable from the viewpoint of clarity of phase separation between the blocks (A) and (A') and the block (B) and improvement of cohesion.

The blocks (A) and (A') may contain only one type or two or more types of the above-described styrene-based monomers. Also, the monomer compositions of the blocks (A) and (A') may be the same or different. Furthermore, the stereoregularities of the styrenic units contained in the blocks (A) and (A') may be the same or different.

In the styrenic thermoplastic elastomer having the (A)-(B)-(A') triblock structure, the lower limit of the total content of the blocks (A) and (A') is preferably 5% by weight or more, 7% by weight or more is more preferable, and 10% by weight or more is even more preferable. The upper limit of the total content of the blocks (A) and (A') is preferably 30% by weight or less, more preferably 27% by weight or less, and even more preferably 25% by weight or less. When the total content of the blocks (A) and (A') is within the above range, it is possible to form a pressure-sensitive adhesive layer that has excellent adhesion to the skin and leaves little adhesive residue when peeled off.

In the styrenic thermoplastic elastomer having the (A)-(B)-(A') triblock structure, the lower limit of the weight average molecular weight of each of the blocks (A) and (A') is preferably 3,000 or more. , 5,000 or more. The upper limit of the weight average molecular weight of each of the blocks (A) and (A') is preferably 50,000 or less, more preferably 35,000 or less. If the weight-average molecular weights of the blocks (A) and (A') are within the above range, the melt viscosity of the hot-melt pressure-sensitive adhesive can be adjusted within an appropriate range. In addition, when the adhesive is prepared, it is possible to form an adhesive layer that has excellent adhesion to the skin and leaves little adhesive residue when peeled off.

The block (B) is not particularly limited as long as it is a polymer block having a glass transition temperature within the above range. For example, it may be a block containing conjugated diene units as a main component. Among the repeating units constituting the block (B), the lower limit of the weight occupied by the conjugated diene-based unit is preferably 60% by weight or more, more preferably 80% by weight or more, and 90% by weight or more of the total weight of the block. More preferably, 95% by weight or more is particularly preferable. In the block (B), the upper limit of the weight of the conjugated diene-based unit may be 100% by weight of the total weight of the block.

Examples of the block (B) include isoprene, butadiene, hydrogenated products thereof (ethylenebutylene, ethylenepropylene), partially hydrogenated products obtained by partial hydrogenation, and isobutylene.

Among these, isoprene is more preferable from the viewpoint of softness, balance of cohesion, and compatibility with tackifying resins and softening agents.

The block (B) may contain only one type of the above-mentioned conjugated diene-based units, or may contain two or more types.

In the styrene-based thermoplastic elastomer having the (A)-(B)-(A') triblock structure, the lower limit of the content of the block (B) is preferably 70% by weight or more, more preferably 73% by weight or more. Preferably, 75% by weight or more is more preferable. The upper limit of the block content is preferably 95% by weight or less, more preferably 93% by weight or less, and more preferably 90% by weight or less. When the content of the block (B) is within the above range, it is possible to form a pressure-sensitive adhesive layer that has excellent adhesion to the skin and leaves little adhesive residue when peeled off.

In the styrenic thermoplastic elastomer having the (A)-(B)-(A') triblock structure, the lower limit of the weight average molecular weight of the block (B) is preferably 40,000 or more, more preferably 50,000 or more. more preferred. The upper limit of the weight average molecular weight of the block (B) is preferably 270,000 or less, more preferably 250,000 or less. If the weight average molecular weight of the block (B) is within the above range, the melt viscosity of the hot-melt pressure-sensitive adhesive can be adjusted within an appropriate range. Furthermore, when the adhesive is prepared, it is possible to form an adhesive layer that has excellent adhesion to the skin and leaves little adhesive residue when peeled off.

A more preferred example of the styrenic thermoplastic elastomer having the (A)-(B)-(A') triblock structure is, for example, (styrene)-(isoprene)-(styrene) triblock copolymer (SIS ), (styrene)-(butadiene)-(styrene) triblock copolymer (SBS), (styrene)-(ethylene/butylene)-(styrene) triblock copolymer (SEBS), (styrene)-(ethylene - Propylene)-(styrene) triblock copolymer (SEPS) and the like can be preferably used.

The lower limit of the weight average molecular weight of the styrene-based thermoplastic elastomer having the triblock structure is preferably 50,000 or more, more preferably 70,000 or more, and even more preferably 100,000 or more. The upper limit of the weight average molecular weight of the styrene-based thermoplastic elastomer having the triblock structure is preferably 350,000 or less, more preferably 300,000 or less, and even more preferably 270,000 or less. When the weight-average molecular weight is within the above range, the melt viscosity of the pressure-sensitive adhesive is lowered and the pressure-sensitive adhesive layer is easily formed.

The lower limit of the molecular weight distribution (Mw/Mn) of the styrene-based thermoplastic elastomer having a triblock structure is 1.0, and the upper limit of the molecular weight distribution (Mw/Mn) is preferably 1.5 or less, and 1.4. The following are more preferred.

In one embodiment of the present invention, the pressure-sensitive adhesive may contain at least one styrenic thermoplastic elastomer having the (A)-(B)-(A') triblock structure, but the (A )-(B)-(A′) It may contain two or more types of styrenic thermoplastic elastomers having a triblock structure.

The styrenic thermoplastic elastomer having the triblock structure can be produced by a known method. Also, commercially available products having the properties described above can be suitably used.

<1.1.2. Other base polymers>
In one embodiment of the present invention, the pressure-sensitive adhesive is a base other than "(A)-(B)-(A') a thermoplastic elastomer having a triblock structure" as long as it does not impair the effects of the present invention. polymer (hereinafter referred to as "other base polymer").

The other base polymer is not particularly limited as long as it is a resin used as a base polymer for adhesives.

Examples of other base polymers include thermoplastic elastomers having a (A)-(B) diblock structure. The (A)-(B) thermoplastic elastomer having a diblock structure includes the (A)-(B) acrylic thermoplastic elastomer having a diblock structure, and the (A)-(B) diblock structure. styrenic thermoplastic elastomers having The block (A) and the block (B) in the (A)-(B) acrylic thermoplastic elastomer and styrene thermoplastic elastomer having a diblock structure are exemplified in the above explanation of the triblock structure. It is the same as said block (A) and said block (B).

When the (A)-(B)-(A′) thermoplastic elastomer having a triblock structure is acrylic, from the viewpoint of compatibility, it is combined with the acrylic thermoplastic elastomer having a diblock structure. It is more preferable to use Similarly, when the thermoplastic elastomer having the (A)-(B)-(A′) triblock structure is styrene, it can be used in combination with the styrene thermoplastic elastomer having the diblock structure. more preferred.

<1.1.3. Tackifying resin>
The temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention may further contain a tackifying resin. The tackifying resin is not particularly limited, and examples thereof include petroleum-based resins, styrene-based resins, rosin-based resins, terpene-based resins, and the like.

Examples of petroleum resins include aliphatic petroleum resins, alicyclic petroleum resins, aromatic petroleum resins, and hydrogenated petroleum resins obtained by hydrogenating them.

Examples of styrene resins include homopolymers such as styrene, methylstyrene, vinyltoluene, methoxystyrene, tertiary butylstyrene, and chlorostyrene. Hydrogenated styrene-based resins (for example, hydrogenated styrene-based resins described above, etc.) may also be used.

Examples of rosin-based resins include natural rosins (eg, gum rosin, tall rosin, wood rosin, etc.), asymmetric rosins, polymerized rosins, glycerol esters of these rosins, and pentaerythritol esters of these rosins. Hydrogenated rosin-based resins (for example, hydrides of the above-mentioned rosin-based resins, etc.) can also be used.

Examples of terpene-based resins include terpene resins, hydrocarbon-modified terpene resins, aromatic modified terpene resins, and phenol-based modified terpene resins. Hydrogenated terpene-based resins (for example, hydrides of the above terpene-based resins, etc.) can also be used.

The temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention may contain only one type of the tackifying resin, or may contain two or more types.

The total amount of the tackifying resin is preferably more than 0% by weight, more preferably 5% by weight or more, still more preferably 10% by weight or more, particularly preferably 20% by weight, based on the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition. % by weight or more. The total amount of the tackifying resin is preferably 50% by weight or less, more preferably 48% by weight or less, and still more preferably 46% by weight or less, relative to the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition. It is preferable that the total amount of the tackifier resin is more than 0% by weight with respect to the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition, because the adhesion to the skin is good. Moreover, when the total amount of the tackifying resin is 50% by weight or less with respect to the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition, the moisture permeability is excellent and the pain at the time of peeling is reduced, which is preferable.

<1.1.4. Softener>
The temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention may further contain a softening agent. The softener is not particularly limited, but examples thereof include oils such as mineral oils, synthetic oils, and vegetable oils.

Examples of the mineral oils include process oil and liquid paraffin. Examples of paraffinic process oils include n-paraffins, isoparaffins and their saturated hydrocarbon derivatives. Examples of naphthenic process oils include cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane and the like.

Examples of synthetic oils include ether oils, ester oils, phosphate esters, and chlorinated paraffins. Examples of the ester oils include palm aliphatic esters; phthalate esters such as di-n-butyl phthalate, di-n-octyl phthalate, bis(2-ethylhexyl) phthalate; bis(2-ethylhexyl) adipate, Adipic acid esters such as di-n-octyl adipate; Sebacate esters such as octyl sebacate, bis(2-ethylhexyl) sebacate and di-n-butyl sebacate; Azelate esters such as bis(2-ethylhexyl) azelate citric acid esters such as acetyl tributyl citrate; trimethylolpropane aliphatic esters such as trimethylolpropane trioleate, which are triesters; pentaerythritol aliphatic esters such as pentaerythritol tetraoleate, which are tetraesters; be done.

Examples of vegetable oils include olive oil, rice germ oil, corn oil, sasanqua oil, camellia oil, castor oil, jojoba seed oil, and eucalyptus leaf oil.

The temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention may contain only one type of the softening agent, or may contain two or more types.

The total amount of the softening agent is preferably 0% to 25% by weight with respect to the total amount of the pressure-sensitive adhesive composition containing the temperature indicating material. It is preferable that the total amount of the softening agent is 10% by weight or more based on the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition, because the melt viscosity of the hot-melt pressure-sensitive adhesive can be adjusted within an appropriate range. Further, when the total amount of the softening agent is 25% by weight or less with respect to the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition, migration of the softening agent to the skin can be suppressed, which is preferable.

<1.1.5. Liquid polymer>
The temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention may further contain a liquid polymer. Examples of the liquid polymer include, but are not limited to, polyisoprene, polybutene, polyisobutylene, and liquefied polybutadiene.

The temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention may contain only one type of the liquid polymer, or may contain two or more types.

The total amount of the liquid polymer is preferably more than 0% by weight, more preferably 3% by weight or more, still more preferably 5% by weight or more, and particularly preferably 10% by weight, based on the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition. % or more. The total amount of the liquid polymer is preferably 40% by weight or less, more preferably 30% by weight or less, and still more preferably 20% by weight or less, relative to the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition. More preferably, the liquid polymer is included when the base polymer is a styrenic thermoplastic elastomer. When the total amount of the liquid polymer is more than 10% by weight with respect to the total amount of the pressure-sensitive adhesive composition containing the temperature indicating material, the adhesiveness to the skin is good, which is preferable. Further, when the total amount of the liquid polymer is 20% by weight or less with respect to the total amount of the pressure-sensitive adhesive composition containing the temperature indicating material, adhesive residue is reduced when the adhesive composition is peeled off from the skin, which is preferable.

The weight average molecular weight of the liquid polymer is preferably 1,000 to 60,000, more preferably 1,000 to 50,000. If the weight-average molecular weight of the liquid polymer is within the above range, the adhesiveness to the skin is good, which is preferable.

<1.1.6. Other Ingredients>
The temperature indicating material-containing pressure-sensitive adhesive composition contains components other than the above-described thermoplastic elastomer, tackifying resin, softening agent, and liquid polymer, if necessary, as long as it does not impair the effects of the present invention. good too. Such ingredients include, for example, antioxidants, colorants, stabilizers, fillers, surfactants, antistatic agents, flame retardants, waxes, antimicrobial agents, perfumes, and the like.

Examples of the antioxidant include phenol-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and the like. Examples of phenolic antioxidants include 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-hydroxy phenyl)propionate]methane and the like. Examples of phosphorus antioxidants include tris(2,4-di-t-butylphenyl)phosphite and bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite. Examples of sulfur-based antioxidants include dilauryl-3,3'-thiodipropionate, dimyristyl-3,3'-thiodipropionate, distearyl-3,3'-thiodipropionate, pentaerythrityl tetrakis(3-laurylthiopropionate) and the like. These antioxidants may be used alone or in combination of two or more. Alternatively, a phenol-based antioxidant that is a primary antioxidant and a phosphorus-based antioxidant or a sulfur-based antioxidant that are secondary antioxidants may be used in combination.

Examples of said stabilizers include 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, pentaerythrityltetrakis-3-(3, 5-di-t-butyl-4-hydroxyphenyl)propionate and pentaerythritol tetrakis(3-laurylthiodipropionate).

Examples of the filler include talc, calcium carbonate, clay silica, mica, wollastonite, feldspar, and aluminum silicate.

Examples of the coloring agent include pigments and dyes.

[1.2. temperature indicator material]
The temperature indicating material-containing pressure-sensitive adhesive composition of the present invention contains a temperature indicating material. In the present invention, the "temperature indicating material" is a thermochromic material that changes color according to temperature changes. A pressure-sensitive adhesive composition containing a temperature indicating material according to one embodiment of the present invention changes color in accordance with a temperature change by containing the pressure-sensitive adhesive containing the thermoplastic elastomer and the temperature indicating material. In addition, since the temperature indicating material is contained in the pressure-sensitive adhesive composition containing the temperature indicating material, the temperature indicating material can be arranged in the pressure-sensitive adhesive layer that contacts the skin when the thermometer attached to the skin is constructed. Therefore, it is possible to realize a thermometer attached to the skin that is not easily affected by environmental temperature.

As used herein, the term "change color" includes color development from colorless to colored, color change from a first color to a second color having a different hue, and loss of color from colored to colorless. I mean.

The temperature indicating material is more preferably a reversible thermochromic material that reversibly changes color in response to temperature changes, that is, restores color when the temperature returns.

The reversible thermochromic material is not particularly limited as long as it reversibly changes color in response to temperature changes, and any material may be used. In one embodiment of the present invention, the reversible thermochromic material includes, for example, a reversible thermochromic material containing a leuco dye, a developer, and a solvent. A leuco dye is an organic dye that reversibly changes color by oxidation and reduction. A developer is an acidic substance that binds with a leuco dye to develop a color. When the leuco dye comes into contact with the color developer, it develops color due to mutual electron enjoyment. The solvent controls their contact and separation. When the temperature rises above a predetermined temperature, the solvent melts and enters between the leuco dye and the developer, separating them. This suppresses the transfer of electrons between the leuco dye and the developer and restores the color development.

Examples of the leuco dyes include fluoran dyes (leuco dyes having a lactone ring in the chemical composition), indoline dyes, spiropyran dyes, rhodamine B lactam dyes, diallylphthalide dyes, and polyaryl dyes. Carbinol dyes, leuco auramine dyes, acyl auramine dyes, etc. can also be used. Examples of the color developer include, but are not limited to, phenols (eg, bisphenol, o-phenylphenol, octylphenol, butylphenol, etc.), carboxylic acids, sulfonic acids, acidic phosphoric acid esters and these. Mention may be made of metal salts. Examples of the solvent include, but are not limited to, alcohol compounds (more preferably higher alcohols), ester compounds (more preferably higher fatty acid esters), ketone compounds, ether compounds, thiols, Phosphate esters, sulfonate esters, sulfides, disulfides, sulfoxides, sulfones, etc. or combinations of two or more thereof may be included.

In one embodiment of the present invention, the reversible thermochromic material may be a material in which a leuco dye, a developer, and a solvent are encapsulated in microcapsules. The average particle size of the microcapsules is 0.5 μm to 50 μm, more preferably 1 μm to 10 μm, still more preferably 1 μm to 5 μm.

A commercially available temperature indicating material can be used as the temperature indicating material. Commercially available temperature indicating materials include, for example, Sakura TC Color manufactured by Sakura Crepas Co., Ltd., Kuromi Color MS Powder LF grade manufactured by Matsui Color and Chemical Industries, and thermosensitive dye capsules manufactured by Nippon Capsule Products.

The temperature indicating material is preferably a temperature indicating material that changes color in the range of 35°C to 38°C. By using a temperature indicating material that changes color in such a temperature range, accurate body temperature measurement is possible without occurrence of color change at normal body temperature and without color change at exothermic body temperature.

The temperature indicating material may be used alone, or two or more temperature indicating materials with different discoloration temperature ranges may be used in combination. For example, when the temperature indicating material-containing pressure-sensitive adhesive composition contains a temperature indicating material whose color disappears at 35 ° C. and a temperature indicating material whose color disappears at 38 ° C., the color of only the temperature indicating material whose color disappears at 35 ° C. The shade of color differs between when the color of both temperature indicating materials disappears and when the color of both temperature indicating materials disappears. Therefore, the body temperature can be measured more accurately based on the shade of color.

The content of the temperature indicating material is preferably 0.4 to 30 parts by weight with respect to 100 parts by weight of the adhesive. The lower limit of the content is 0.4 parts by weight, preferably 0.5 parts by weight or more. The upper limit of the content is 30 parts by weight, preferably 20 parts by weight or less, still more preferably 10 parts by weight or less, and particularly preferably 5 parts by weight or less. If the content of the temperature indicating material is 0.4 parts by weight or more, the temperature indicating material-containing pressure-sensitive adhesive composition is more preferable because the visibility of discoloration is excellent. Moreover, if the content of the temperature indicating material is 30 parts by weight or less, it is more preferable from the viewpoint of cost and adhesive strength.

[1.3. Method for producing pressure-sensitive adhesive composition containing temperature indicating material]
The method for producing the temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention is not particularly limited. A method of mixing by heating and kneading using is mentioned. The order of mixing each material is not particularly limited, and all the materials may be mixed at the same time, or the temperature indicating material may be added and mixed after each component of the adhesive is mixed. When the temperature indicating material is added after mixing each component of the adhesive, the order of mixing each component of the adhesive is not particularly limited. The base polymer may be mixed after each component of the pressure-sensitive adhesive other than the above is mixed, or vice versa.

The temperature indicating material-containing pressure-sensitive adhesive composition is preferably a hot-melt pressure-sensitive adhesive composition. A hot-melt adhesive composition is an adhesive composition that is solid and sticky at room temperature and that can be applied to an adherend by heating to melt the resin. Since the hot-melt pressure-sensitive adhesive composition is solvent-free, there is no possibility that the solvent will remain in the pressure-sensitive adhesive layer. Therefore, it is possible to suppress adverse effects such as skin irritation caused by the solvent, and it is suitable for use in contact with a living body such as the skin. In addition, when forming an adhesive layer using a hot-melt adhesive composition, a drying step for volatilizing the solvent is not required, which is suitable for improving productivity.

Furthermore, since the hot-melt pressure-sensitive adhesive composition is solid at room temperature, there is no risk of the temperature indicating material settling during storage, which is preferable.

The upper limit of the solvent content of the hot melt type temperature indicating material-containing adhesive composition is preferably less than 0.5% by weight, more preferably less than 0.1% by weight. The lower limit of the solvent content is desirably non-detectable, for example, 0.001% by weight or more. As used herein, the term "solvent" refers to solvents generally used for solvent-based pressure-sensitive adhesives. Examples of such solvents include toluene, ethyl acetate, methyl ethyl ketone, cyclohexane, and the like.

In one embodiment of the present invention, as an example of a method for producing the hot-melt type temperature indicating material-containing pressure-sensitive adhesive composition, a step of mixing and melting each component of the pressure-sensitive adhesive other than the base polymer; A method including a step of mixing a base polymer with a melt to melt the base polymer, and a step of adding the temperature indicating material to the obtained melt of the pressure-sensitive adhesive and dispersing it in the pressure-sensitive adhesive can be mentioned. In the method, the step of mixing and melting each component of the pressure-sensitive adhesive other than the base polymer is performed, for example, by stirring each component in a heated state. The heating temperature at this time is, but not limited to, 150° C. to 190° C., for example. In addition, the step of mixing the base polymer with the melt obtained in this step to melt the base polymer is performed, for example, by kneading the melt and the base polymer in a heated state. The heating temperature at this time is, but not limited to, 150° C. to 190° C., for example. The step of adding the temperature indicating material to the obtained melt of the adhesive and dispersing it is performed by adding the temperature indicating material to the obtained melt of the adhesive and kneading in a heated state. The heating temperature at this time is, but not limited to, 140° C. to 180° C., for example.

The above-described production method includes a step of mixing and melting each component of the pressure-sensitive adhesive other than the base polymer, and a step of mixing the base polymer with the resulting melt and melting the base polymer. The method of obtaining the melt of the adhesive may be a method of melting by kneading all the components of the adhesive at the same time in a heated state.

In one embodiment of the present invention, the lower limit of the melt viscosity at 160°C of the hot melt type temperature indicating material-containing adhesive composition is preferably 500 mPa·s or more, more preferably 5,000 mPa·s or more. The upper limit of the melt viscosity at 160°C of the hot melt type temperature indicating material-containing adhesive composition is preferably 310,000 mPa s or less, more preferably 200,000 mPa s or less, and even more preferably 100,000 mPa s or less. . If the melt viscosity is 500 mPa·s or more, there is no possibility that the temperature indicating material will settle in a short time (within 24 hours) during heating and melting. When the melt viscosity is 310,000 mPa·s or less, the coating properties are excellent and the coating on the substrate is facilitated. If it is a hot-melt type temperature indicating material-containing adhesive composition, it is possible to easily adjust the melt viscosity to a range in which the temperature indicating material does not settle.

The obtained hot-melt type temperature indicating material-containing pressure-sensitive adhesive composition is coated using a general hot-melt type adhesive coating method and cooled to obtain a solid and sticky temperature indicating material-containing pressure-sensitive adhesive. A composition can be obtained. The coating method is not particularly limited, and examples thereof include die coater, spray coating, bead, roll coater and flexographic printing.

[2. Thermometer attached to the skin]
A thermometer attached to the skin according to one embodiment of the present invention includes an adhesive layer made of the temperature indicating material-containing adhesive composition, and a substrate layer laminated with the adhesive layer.

In the skin patch thermometer according to one embodiment of the present invention, the adhesive layer made of the temperature indicating material-containing adhesive composition is the part that contacts the skin when the skin patch thermometer is attached to the skin. The pressure-sensitive adhesive layer may be laminated on the substrate layer, and is formed, for example, by applying the pressure-sensitive adhesive composition containing the temperature indicating material to the substrate layer. When the temperature indicating material-containing pressure-sensitive adhesive composition is a hot-melt pressure-sensitive adhesive composition, the temperature indicating material-containing pressure-sensitive adhesive composition in a molten state is applied to the base layer using a die coater, a roll coater, or the like. , coating, and then cooling, a solid and sticky adhesive layer can be obtained.

The thickness of the adhesive layer is preferably 10 µm to 500 µm, more preferably 20 µm to 200 µm. Sufficient adhesiveness can be imparted by setting the thickness of the pressure-sensitive adhesive layer to 10 μm or more. Further, it is preferable that the thickness of the pressure-sensitive adhesive layer is 500 μm or less, because the response to temperature is good.

The base layer is laminated with the pressure-sensitive adhesive layer, and it is sufficient that the base layer has transparency to the extent that discoloration of the pressure-sensitive adhesive layer can be visually recognized from the side of the base layer. Such substrate layers may be in the form of films (sheets). The transparency of the substrate layer is not particularly limited as long as the discoloration of the pressure-sensitive adhesive layer can be visually recognized, but the haze value is preferably 50% or less, more preferably 20% or less, and further Preferably, it is 10% or less. Here, in this specification, the "haze value" is an index relating to the transparency of a film, and refers to the ratio of diffuse transmitted light to the total transmitted light when an object to be measured is irradiated with visible light, and conforms to JIS K7136. measured by

The material of the base material layer is not limited to this, but is preferably a plastic film (sheet). Low density polyethylene (LDPE), linear low density polyethylene (LLDPE), etc.), polypropylene (e.g., oriented polypropylene (OPP), non-oriented polypropylene (CPP), etc.), polyolefins such as ethylene-propylene copolymer; polyurethane; nylon polyvinylidene chloride; polyvinylidene chloride copolymer; polyvinylidene fluoride; polyvinyl chloride; polystyrene; The substrate layer may be a laminate of these plastic films.

Among them, a polyurethane film is more preferable in that it has excellent moisture permeability and stretchability.

The thickness of the base material layer is preferably 10 μm to 500 μm, more preferably 10 μm to 200 μm. If the thickness of the base material layer is 10 μm or more, the strength of the base material is high and the layer can be easily peeled off from the skin, which is preferable. Further, if the thickness of the base material layer is 500 μm or less, it is preferable because it is difficult to peel off from the skin.

The pressure-sensitive adhesive layer may have a release sheet on the side opposite to the base layer. The release sheet is a sheet to be removed when using a thermometer attached to the skin, and is not particularly limited as long as it is generally used as a release sheet. Examples of materials for the release sheet include polyesters (eg, polyethylene terephthalate (PET), etc.), polyolefins (eg, polypropylene, polyethylene, etc.), and cellulose compounds (eg, paper, etc.).

The thermometer attached to the skin according to one embodiment of the present invention may comprise an adhesive layer made of the temperature indicating material-containing adhesive composition, and a base material layer laminated with the adhesive layer. Alternatively, two or more temperature indicating material-containing pressure-sensitive adhesive compositions containing temperature indicating materials having different discoloration temperatures may be arranged side by side on the substrate layer. For example, on the base material, a part laminated with a temperature indicating material-containing pressure-sensitive adhesive composition containing a temperature indicating material that changes color at 35 ° C., and a part laminated with a temperature indicating material-containing pressure-sensitive adhesive composition containing a temperature indicating material that changes color at 38 ° C. is formed, the degree of heat generation can be detected in addition to the presence or absence of heat generation from the change in color.

That is, one embodiment of the present invention is as follows.

[1] A temperature indicating material-containing adhesive composition containing a temperature indicating material that changes color depending on temperature and an adhesive, wherein the adhesive has a (A)-(B)-(A') triblock structure. A temperature indicating material-containing pressure-sensitive adhesive composition containing 6.5% by weight to 69.0% by weight of a thermoplastic elastomer based on the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition.

[2] The temperature indicating material-containing according to [1], wherein the (A)-(B)-(A') thermoplastic elastomer having a triblock structure is an acrylic thermoplastic elastomer or a styrene thermoplastic elastomer. Adhesive composition.

[3] The temperature indicating material-containing pressure-sensitive adhesive composition according to [1] or [2], further comprising a tackifying resin and a softening agent.

[4] The pressure-sensitive adhesive composition containing a temperature indicating material according to any one of [1] to [3], further comprising a liquid polymer.

[5] The temperature indicating material-containing pressure-sensitive adhesive composition according to any one of [1] to [4], which is a hot-melt pressure-sensitive adhesive composition.

[6] A skin patch thermometer comprising an adhesive layer made of the temperature indicating material-containing adhesive composition according to any one of [1] to [5], and a substrate layer laminated with the adhesive layer.

[7] The skin patch thermometer according to [6], wherein the base layer has transparency such that discoloration of the pressure-sensitive adhesive layer can be visually recognized from the side of the base layer.

[8] The skin patch thermometer according to [6] or [7], wherein the base layer is made of a polyester film, a polyolefin film, or a polyurethane film.

[9] The skin patch thermometer according to any one of [6] to [8], wherein the base layer has a thickness of 10 μm to 500 μm.

[10] The skin patch thermometer according to any one of [6] to [9], wherein the adhesive layer has a thickness of 10 μm to 500 μm.

The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.

[1. Preparation of adhesive composition containing temperature indicating material]
<Example 1>
In a stirring kneader, 36 parts by weight of hydrogenated petroleum resin (alicyclic saturated hydrocarbon resin Alcon (registered trademark, hereinafter the same) P-100 manufactured by Arakawa Chemical Industries, Ltd.), 18 parts by weight of liquid paraffin (Moresco White (registered trademark, the same applies hereinafter) P-350P), 0.5 parts by weight of a phenolic primary antioxidant (Adeka Dove (registered trademark, the same applies hereinafter) AO-60G manufactured by ADEKA Co., Ltd.), and 0.5 parts by weight of A phosphorus-based secondary antioxidant (Irgafos (registered trademark, hereinafter the same) 168 manufactured by BASF) was added. These were stirred in a heated state of 150 to 190° C. and melted sufficiently.

In the resulting melt, 32 parts by weight of thermoplastic elastomer SIS (Quintac (registered trademark, hereinafter the same) 3520 manufactured by Nippon Zeon Co., Ltd., SIS block copolymer (triblock: 22% by weight, diblock: 78% by weight, styrene%: 14% by weight)) and 14 parts by weight of polyisoprene (LIR-30 manufactured by Kuraray Co., Ltd.) are added and kneaded in a stirring kneader at a temperature of 150 to 190°C. sufficiently melted the base polymer and evenly dispersed in the melt. 1.0 part by weight of a thermochromic material (TC powder TC-PQ35, manufactured by Sakura Crepas Co., Ltd.) is added to the obtained melt of the adhesive, and kneaded in a heated state of 140 to 180 ° C. The mixture was uniformly dispersed to prepare 102 parts of a temperature indicating material-containing pressure-sensitive adhesive composition.

<Example 2>
32 parts by weight of thermoplastic elastomer Quintac 3520 was mixed with 16 parts by weight of thermoplastic elastomer Quintac 3520 and 16 parts by weight of thermoplastic elastomer Quintac 3421 (manufactured by Nippon Zeon Co., Ltd., SIS block copolymer (triblock: 74% by weight, diblock A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 1, except that the content was changed to: 26% by weight, styrene%: 15% by weight)).

<Example 3>
A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 1, except that 32 parts by weight of the thermoplastic elastomer Quintac 3520 was changed to 32 parts by weight of the thermoplastic elastomer Quintac 3421.

<Example 4>
16 parts by weight of thermoplastic elastomer Quintac 3421, 16 parts by weight of thermoplastic elastomer Quintac 3270 (manufactured by Nippon Zeon Co., Ltd., SIS block copolymer (triblock: 33% by weight, diblock: 67% by weight, styrene %: 24 A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 2, except that the content was changed to % by weight.

<Example 5>
16 parts by weight of thermoplastic elastomer Quintac 3421, 16 parts by weight of thermoplastic elastomer Quintac 3280 (manufactured by Nippon Zeon Co., Ltd., SIS block copolymer (triblock: 83% by weight, diblock: 17% by weight, styrene%: 25 A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 2, except that the content was changed to % by weight)).

<Example 6>
As the thermoplastic elastomer, instead of 32 parts by weight of the thermoplastic elastomer Quintac 3520, 40 parts by weight of the thermoplastic elastomer Clarity (registered trademark, hereinafter the same) LA3320 (poly n-butyl acrylate (PnBA) and polymethyl methacrylate (PMMA) and a triblock copolymer (hereinafter referred to as PMMA/PnBA/PMMA), triblock: 100% by weight, methyl methacrylate (MMA)%: 16% by weight), and 36 parts by weight of water as a tackifying resin Instead of the added petroleum resin (alicyclic saturated hydrocarbon resin Alcon P-100), 45 parts by weight of polystyrene resin (YS Resin SX-100 manufactured by Yasuhara Chemical Co., Ltd.) was added, and 18 parts by weight of softener was added. Instead of liquid paraffin (Moresco White P-350P), 15 parts by weight of dioctyl sebacate (DOS, manufactured by Toyokuni Oil Co., Ltd.) was added, except that 14 parts by weight of polyisoprene (LIR-30) was not added. prepared a temperature indicating material-containing pressure-sensitive adhesive composition in the same manner as in Example 1.

The triblock ratio of clarity is a value measured by GPC measurement, and the MMA % is a value measured by ¹ H-NMR measurement (hereinafter the same).

<Example 7>
As a thermoplastic elastomer, instead of 40 parts by weight of thermoplastic elastomer Clarity LA3320, 50 parts by weight of acrylic thermoplastic elastomer Clarity LA2140 (PMMA-PnBA-PMMA, triblock: 100% by weight, MMA%: 23% by weight) and 10 parts by weight of thermoplastic elastomer Clarity LA1114 (a diblock copolymer of poly n-butyl acrylate (PnBA) and polymethyl methacrylate (PMMA) (hereinafter referred to as PMMA-PnBA) diblock: 100% by weight, MMA%: 7% by weight)), 45 parts by weight of polystyrene resin (YS Resin SX-100) was changed to 30 parts by weight, and 15 parts by weight of dioctyl sebacate (DOS) was added as a softening agent. A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 6, except that 10 parts by weight of acetyl tributyl citrate (manufactured by ATBC Taoka Chemical Co., Ltd.) was added instead of .

<Example 8>
A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 7, except that 50 parts by weight of the thermoplastic elastomer Clarity LA2140 was changed to 50 parts by weight of the thermoplastic elastomer Clarity LA3320 as the thermoplastic elastomer.

<Example 9>
As the thermoplastic elastomer, the amount of 50 parts by weight of thermoplastic elastomer Clarity LA3320 was changed to 56.7 parts by weight, 10 parts by weight of thermoplastic elastomer Clarity LA1114 was not added, and 30 parts by weight of polystyrene resin (YS resin SX-100) was changed to 33.3 parts by weight, and as antioxidants, 0.5 parts by weight of a phenolic primary antioxidant (ADEKA STAB AO-60G) and 0.5 parts by weight of a phosphorus secondary antioxidant were added. 101 parts of a temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 8, except that the antioxidant (Irgafos 168) was not added.

<Example 10>
The amount of 56.7 parts by weight of thermoplastic elastomer Clarity LA3320 was changed to 66.7 parts by weight, and the amount of 33.3 parts by weight of polystyrene resin (YS Resin SX-100) was changed to 23.3 parts by weight. A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 9 except for the above.

<Example 11>
A temperature indicating material was used in the same manner as in Example 2, except that 1.0 parts by weight of the thermochromic material TC powder TC-PN38 was added instead of 1.0 parts by weight of the thermochromic material TC powder TC-PQ35. A material-containing adhesive composition was prepared.

<Example 12>
A pressure-sensitive adhesive composition containing a temperature indicating material was prepared in the same manner as in Example 2, except that the amount of the thermochromic material TC powder TC-PQ35 (1.0 parts by weight) was changed to 0.5 parts by weight as the temperature indicating material.

<Example 13>
Example 2 except that the amount of 1.0 parts by weight of the thermochromic material TC powder TC-PQ35 as the temperature indicating material was changed to 20.0 parts by weight to prepare 121 parts by weight of the pressure-sensitive adhesive composition containing the temperature indicating material. A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner.

<Comparative Example 1>
The amount of 40 parts by weight of the thermoplastic elastomer Clarity LA3320 in Example 6 was changed to 12 parts by weight, the amount of 45 parts by weight of the polystyrene resin (YS Resin SX-100) was changed to 13.5 parts by weight, and 15 The amount of dioctyl sebacate (DOS) in parts by weight was changed to 4.5 parts by weight, the amount of phosphorus secondary antioxidant (Irgafos 168) was changed to 0.15 parts by weight, and the phenolic primary antioxidant (Adekastab AO-60G) was changed to 0.15 parts by weight, 1.0 parts by weight of the thermochromic material (TC powder TC-PQ35), and 70 parts by weight of toluene as a solvent were mixed in a stirrer. and uniformly dispersed by stirring in a room temperature environment of 20 to 30° C. to prepare 101 parts by weight of a solvent-type temperature indicating material-containing pressure-sensitive adhesive composition.

<Comparative Example 2>
32 parts by weight of the thermoplastic elastomer Quintac 3520 was changed to 32 parts by weight of polyisobutylene (Oppano 1N50SF (registered trademark, hereinafter the same) BASF), and 14 parts by weight of polyisoprene (LIR-30) was replaced by 14 parts by weight of polybutene ( 102 parts by weight of a temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 1, except that polybutene 40N (registered trademark, hereinafter the same) manufactured by NOF Corporation) was used.

<Comparative Example 3>
A temperature indicating material was prepared in the same manner as in Comparative Example 2, except that 32 parts by weight of polyisobutylene (Oppano 1N50SF) was changed to 32 parts by weight of amorphous polyalphaolefin (VESTOPLAST (registered trademark, hereinafter the same) 828 manufactured by Evonik). A containing adhesive composition was prepared.

<Comparative Example 4>
Temperature indicator material is contained in the same manner as in Example 1, except that the amount of 32 parts by weight of the thermoplastic elastomer Quintac 3520 is changed to 23 parts by weight, and the amount of 14 parts by weight of polyisoprene (LIR-30) is changed to 23 parts. An adhesive composition was produced.

<Comparative Example 5>
A temperature indicating material is contained in the same manner as in Comparative Example 4, except that the amount of 23 parts by weight of the thermoplastic elastomer Quintac 3520 is changed to 28 parts by weight, and the amount of 23 parts by weight of polyisoprene (LIR-30) is changed to 18 parts. An adhesive composition was produced.

<Comparative Example 6>
The amount of 40 parts by weight of thermoplastic elastomer Clarity LA3320 was changed to 70 parts by weight, the amount of 45 parts by weight of polystyrene resin (YS Resin SX-100) was changed to 20 parts by weight, and dioctyl sebacate (DOS) was added. Instead, 101 parts by weight of a temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 6 except that 10 parts by weight of acetyl tributyl citrate (ATBC) was added and no antioxidant was added. bottom.

<Comparative Example 7>
As a temperature indicating material, instead of 1.0 parts by weight of the thermochromic material (TC powder TC-PQ35), 1.0 parts by weight of (TC powder TC-PR32) was added in the same manner as in Example 2. A pressure-sensitive adhesive composition containing a temperature indicating material was produced.

<Comparative Example 8>
As the temperature indicating material, instead of 1.0 parts by weight of the thermochromic material (TC powder TC-PR32), 1.0 parts by weight of (TC powder TC-PG45) was added in the same manner as in Comparative Example 8. A pressure-sensitive adhesive composition containing a temperature indicating material was produced.

<Comparative Example 9>
A temperature indicating material-containing pressure-sensitive adhesive composition was prepared in the same manner as in Example 2, except that the amount of the thermochromic material (TC powder TC-PQ35) of 1.0 parts by weight was changed to 0.3 parts by weight.

The compositions of the temperature indicating material-containing pressure-sensitive adhesive compositions prepared in Examples 1 to 13 and Comparative Examples 1 to 9 are shown in Tables 1 and 2, respectively. In Tables 1 and 2, the units of numerical values indicating compositions are parts by weight.

　〔２．粘着シート（皮膚貼付体温計）の作製〕
　実施例１～１３および比較例２～９で得られた示温材含有粘着剤組成物の溶融物を、スロットコーター（株式会社サンツール製）を用いて、ポリエチレンテレフタレートフィルム（ＰＥＴ－５０　ニッパ株式会社製）に、膜厚５０～６０μｍで塗工し、粘着シート（皮膚貼付体温計）を作製した。

[2. Preparation of adhesive sheet (thermometer attached to skin)]
The melts of the temperature indicating material-containing pressure-sensitive adhesive compositions obtained in Examples 1 to 13 and Comparative Examples 2 to 9 were coated with a polyethylene terephthalate film (PET-50, Nippa Co., Ltd.) using a slot coater (manufactured by Suntool Co., Ltd.). (manufacturer) to a film thickness of 50 to 60 μm to prepare an adhesive sheet (thermometer attached to the skin).

Since the solvent-type temperature indicating material-containing adhesive composition of Comparative Example 1 contains a solvent, it is coated on a polyethylene terephthalate film using a bar coater (manufactured by Imoto Seisakusho Co., Ltd.), the solvent is dried, and the film thickness is 50 to 60 μm. A pressure-sensitive adhesive sheet was produced. In the solvent-type temperature indicating agent-containing pressure-sensitive adhesive composition of Comparative Example 1, the temperature indicating agent settled at room temperature (23° C.). When the pressure-sensitive adhesive composition containing the temperature indicating material in which the temperature indicating material is sedimented is applied to a polyethylene terephthalate film, the temperature indicating material is unevenly distributed, causing variations among the pressure-sensitive adhesive sheets. Furthermore, visibility is adversely affected. In Comparative Example 1, since the temperature indicating agent settled at room temperature, the temperature indicating agent sedimentation evaluation at 160° C. was not performed.

On the other hand, in the hot-melt type temperature indicating material-containing pressure-sensitive adhesive composition other than Comparative Example 1, no sedimentation of the temperature indicating material was observed at room temperature (23 ° C.) and high temperature (160 ° C.), and stirring work was performed during film coating. was unnecessary and no variation occurred. In Comparative Example 1, since the solvent evaporates at a high temperature (160° C.), no test was conducted on the sedimentation of the temperature indicating material at a high temperature.

[3. Evaluation test〕
(1) Adhesiveness to Skin The prepared pressure-sensitive adhesive sheet was cut into strips (10 mm×10 mm) to obtain test pieces. This test piece was attached to a human wrist (on the radial artery), and peeling and/or floating of the test piece was visually confirmed after 6 hours. Evaluation criteria are as follows.
A: No peeling and/or lifting of the test piece.
◯: Slight peeling and/or lifting of the test piece. There is no problem in practical use.
x: Peeling and/or lifting of the test piece is large. It can be said that the adhesiveness to the skin is low.

(2) Adhesive residue After the adhesiveness test to the skin, the adhesive sheet was peeled off from the skin in a 90° direction, and the presence or absence of adhesive residue on the skin was visually confirmed. The peeling speed was 230 cm/min. Evaluation criteria are as follows.
A: No adhesive remained on the skin.
○: A small amount of adhesive remains on the skin. There is no problem in practical use.
x: A large amount of adhesive remains on the skin. It can be said that there is a problem with cohesion.

(3) Confirmation of color change (discoloration) of temperature indicating material (Test method described in Examples)
The produced pressure-sensitive adhesive sheet was cut into strips (10 mm×10 mm) to obtain test pieces. This test piece is attached to a human wrist (on the radial artery), and the color at normal body temperature (36 ° C. or higher, less than 37.5 ° C.) and fever temperature (37.5 to 40.5 ° C.) was visually confirmed.
Body temperature at normal temperature ◯: No change in color, ×: Change in color (discoloration or fading).
Body temperature at the time of fever ○: color change (discoloration or color fading), x: no color change.

(4) Melt Viscosity Melt viscosity was measured according to JIS K 6682 using a viscometer (DV2T, manufactured by Eiko Seiki Co., Ltd.). The measurement conditions are as follows.
Measurement temperature: 160°C
Rotation speed: 5-50rpm
Spindle: SC4-27
(5) Checking the presence or absence of sedimentation of the temperature indicating material Weigh 50 g of the temperature indicating material-containing pressure-sensitive adhesive composition in a mayonnaise bottle (125 ml), store it at room temperature (23 ° C.) and 160 ° C. for 24 hours. Presence or absence of sedimentation of the temperature indicating material was confirmed.
○: No sedimentation.
x: Precipitation occurred.

[4. result〕
(A)-(B)-(A′) A temperature indicating material-containing pressure-sensitive adhesive containing 6.5% to 69.0% by weight of a thermoplastic elastomer having a triblock structure with respect to the total amount of the temperature indicating material-containing pressure-sensitive adhesive composition. The pressure-sensitive adhesive sheet (skin-adhered thermometer) using the composition has suitable adhesion to the skin such that peeling and/or floating of the test piece does not pose a problem after 6 hours from the time of application to the skin. It was shown that the amount of adhesive residue was reduced.

On the other hand, in the pressure-sensitive adhesive sheets using the temperature-indicating material-containing pressure-sensitive adhesive compositions of Comparative Examples 2 and 3, which used thermoplastic elastomers containing no triblock structure, adhesive residue was observed on the skin. (A)-(B)-(A') Adhesive residue was observed on the skin in the temperature indicating material-containing pressure-sensitive adhesive compositions of Comparative Examples 4 and 5, in which the thermoplastic elastomer having a triblock structure was 6.0% by weight or less. . (A)-(B)-(A') The temperature indicating material-containing adhesive composition of Comparative Example 6, in which the content of the thermoplastic elastomer having a triblock structure is 69.3% by weight, has reduced adhesion to the skin. bottom.

The pressure-sensitive adhesive sheet (skin thermometer) using the temperature indicating material-containing pressure-sensitive adhesive composition of Examples 1 to 10 containing TC powder TC-PQ35 whose temperature indicating material has a color change temperature of 35 ° C. has a body temperature of 37.5 to 38 ° C. A clear change in color (the color becomes lighter) was confirmed at the time of . In the adhesive sheet (skin thermometer) using the temperature indicating material-containing adhesive composition of Example 11 containing TC powder TC-PN38 whose temperature indicating material has a color change temperature of 38 ° C., the temperature is clear when the body temperature is 39 to 40 ° C. A change in color (lightening of the color) was confirmed. On the other hand, the adhesive sheet (skin thermometer) using the temperature indicating material-containing adhesive composition of Comparative Example 7 containing TC powder TC-PR32 whose temperature indicating material has a color change temperature of 32 ° C. has a color change at normal body temperature. showed change. The adhesive sheet (skin thermometer) using the temperature indicating material-containing adhesive composition of Comparative Example 8 containing TC powder TC-PG45 whose temperature indicating material has a color change temperature of 45 ° C. is heated (37.5 to 40 ° C.). showed no color change at body temperature.

Here, an adhesive sheet was attached to the outer wall surface of a mayonnaise bottle (125 ml) filled with water, and a hot stirrer was used to visually confirm the change in color accompanying the temperature rise (heating rate: 0.1 to 0.1). 3°C/min). As a result, it was confirmed that the color of TC powder TC-PQ35 began to fade at an outer wall surface temperature of 35°C, and completely disappeared at 40°C. Further, it was confirmed that the color of TC powder TC-PN38 began to fade at an outer wall surface temperature of 37°C, and completely disappeared at 40°C. On the other hand, TC powder TC-PR32 was completely decolored at an outer wall surface temperature of less than 35°C, and TC powder TC-PG45 did not lose its color even at an outer wall surface temperature of 40°C. The temperature-indicating material-containing pressure-sensitive adhesive composition containing TC powder TC-PQ35 showed a clear change in color (the color became lighter) when the body temperature was 37.5 to 38°C. The temperature indicating material-containing pressure-sensitive adhesive composition containing TC powder TC-PN38 showed a clear color change when the body temperature was 39 to 40°C. From these results, it was found that a temperature indicating material whose skin surface temperature is about 2° C. lower than body temperature and whose color changes in the temperature range of 35 to 38° C. is suitable for body temperature measurement.

In the pressure-sensitive adhesive sheet using the temperature indicating material-containing pressure-sensitive adhesive composition of Example 12, in which the temperature indicating material content is 0.5 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive, the temperature indicating material-containing pressure-sensitive adhesive composition is 60 μm Visibility was observed when the coating was applied with a film thickness of . On the other hand, in the pressure-sensitive adhesive sheet using the temperature indicating material-containing pressure-sensitive adhesive composition of Comparative Example 9, in which the content of the temperature indicating material is 0.3 parts by weight with respect to 100 parts by weight of the pressure-sensitive adhesive, the temperature indicating material-containing pressure-sensitive adhesive Visibility was not observed when the composition was applied in a film thickness of 60 µm.

The temperature indicating material-containing pressure-sensitive adhesive composition according to one embodiment of the present invention and the skin-adhered thermometer having an adhesive layer made of the temperature indicating material-containing pressure-sensitive adhesive composition are less susceptible to environmental temperature and have good adhesion to the skin. Excellent, adhesive residue on the skin is reduced. Therefore, it is suitably used as an adhesive layer of a skin-adhered thermometer for easily measuring human body temperature as a measure against infection.

Claims (10)

A temperature indicating material-containing adhesive composition containing a temperature indicating material that changes color depending on temperature and an adhesive,
The adhesive contains a thermoplastic elastomer having a (A)-(B)-(A') triblock structure in an amount of 6.5% to 69.0% by weight based on the total amount of the temperature indicating material-containing adhesive composition. , temperature-indicating material-containing pressure-sensitive adhesive composition. The temperature indicating material-containing pressure-sensitive adhesive composition according to claim 1, wherein the (A)-(B)-(A') thermoplastic elastomer having a triblock structure is an acrylic thermoplastic elastomer or a styrene thermoplastic elastomer. thing. The temperature indicating material-containing pressure-sensitive adhesive composition according to claim 1, further comprising a tackifying resin and a softening agent. The temperature indicating material-containing pressure-sensitive adhesive composition according to claim 1, further comprising a liquid polymer. The temperature indicating material-containing pressure-sensitive adhesive composition according to claim 1, which is a hot-melt pressure-sensitive adhesive composition. A skin-adhered thermometer comprising an adhesive layer made of the temperature-indicating material-containing adhesive composition according to claim 1, and a base material layer laminated with the adhesive layer. The skin patch thermometer according to claim 6, wherein the base layer has transparency such that discoloration of the adhesive layer can be visually recognized from the side of the base layer. The skin patch thermometer according to claim 6, wherein the base material layer is made of a polyester film, a polyolefin film, or a polyurethane film. The skin patch thermometer according to claim 6, wherein the base layer has a thickness of 10 µm to 500 µm. The skin patch thermometer according to claim 6, wherein the adhesive layer has a thickness of 10 µm to 500 µm.