JP6750989B2 - Aroma sheet manufacturing method - Google Patents

Description

The present invention relates to a method for producing an aroma sheet.

There are various fragrance members that cause a scent to float in the space, but fragrance sheets are used because they are easy to process. For example, in Patent Document 1, at least one of a base sheet or a pressure-sensitive adhesive layer of a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed on one surface of a base sheet is coated with or contains an aromatic agent. In addition, an aromatic pressure-sensitive adhesive laminated sheet body is disclosed in which a plurality of pressure-sensitive adhesive sheet bodies are laminated. In addition, Patent Document 2 discloses a method for producing a protective film in which the surface roughness is adjusted to a constant value in order to improve the visibility (appearance) of the pressure-sensitive adhesive layer surface.

Japanese Utility Model Publication No. 57-97544 Japanese Patent No. 4673344

However, in Patent Document 1, no study has been made on a method for producing an aroma sheet that improves aroma persistence and appearance, and further improvement is required. Further, Patent Document 2 does not contain a liquid fragrance in the pressure-sensitive adhesive layer, but if a similar manufacturing method is carried out when a liquid fragrance is used, the fragrance persistence and the appearance may rather be impaired. There was found.

An object of the present invention is to provide a method for producing an aroma sheet including a layer containing a bonding agent and a liquid perfume (hereinafter, also referred to as “aromatic functional bonding layer”), which has good aroma persistence and appearance, and a method for producing an aroma sheet. Is to provide.

When the above problems were examined, it was found that a fragrance sheet having a good fragrance durability and appearance can be obtained by providing a specific drying step. Although this mechanism is not clear, it is possible to reduce unevenness caused by excessive migration of the bonding agent to the surface layer, which is so-called migration, in the bonding layer, as compared with the case where rapid drying is performed. It is presumed that it is possible to prevent deterioration of physical properties such as uniform distribution and porosity.

The present invention provides a fragrance sheet having a coating step of coating a mixed liquid containing a binder and a liquid flavor on a base sheet, and a drying step of drying the sheet coated by the coating step. In the method, the drying step includes a drying step A in which the coated sheet is kept under an atmosphere of 10 to 45° C. at a wind speed of less than 1 m/sec, and a wind speed of 1 m/sec or more after the drying step A. The present invention relates to a method for producing an aroma sheet, which has a drying step B of maintaining the atmosphere at 45 to 95°C.

According to the present invention, in the method for producing an aroma sheet containing a fragrance functional bonding layer, the fragrance persistence is good, the coated surface of the fragrance functional bonding layer is uniform and has less bubbles, and the appearance is good. A manufacturing method can be provided.

It is a schematic sectional drawing which shows one embodiment of this invention. It is a schematic sectional drawing which shows one embodiment of this invention. It is a schematic sectional drawing which shows one embodiment of this invention.

The manufacturing method of the present invention has a coating step and a drying step.

The coating step according to the present invention is a step of coating a mixed liquid containing a bonding agent and a liquid flavor on a base material sheet. As the coating method, any suitable method can be adopted. For example, the coating may be performed continuously or batchwise. As a continuous method, the mixed solution is continuously supplied to a coating device, by a discharging means such as a die attached to the coating device, a method of extruding into a thin layer on a substrate sheet, a roll coater, a knife coater, Examples include a method using a roll knife coater, a reverse coater, a gravure coater and the like. Examples of the batch method include a method of casting the mixed solution on a base material sheet to form a thin layer using an applicator, a Meyer bar, a knife coater, or the like.

A polymer resin sheet or the like can be used as the substrate sheet. As the polymer resin sheet, for example, a known plastic material such as polyethylene terephthalate, polyvinylidene chloride, polyethylene, polypropylene, polycarbonate, polystyrene can be used, and can be formed by any method such as a solvent casting method or an extrusion method. ..

Further, as will be described later, the base sheet may have a single-layer form or a multi-layer form, but at least one of the base sheets provided on the outermost side of the base sheet has a fragrance viewpoint. Therefore, the gas permeable sheet is preferable. In the present specification, the gas permeable sheet refers to a sheet having an oxygen permeability of 1,000×10 ⁻¹⁵ mol/(m ² ·s·Pa) or more. From the viewpoint of aromaticity, the gas permeable sheet preferably has an oxygen permeability of 1,500×10 ⁻¹⁵ mol/(m ² ·s·Pa) or more, and 2,500×10 ⁻¹⁵ mol/(m). ² ·s·Pa) or more is more preferable. Further, from the viewpoint of fragrance persistence, the oxygen permeability is preferably 35,000×10 ⁻¹⁵ mol/(m ² ·s·Pa) or less, and 30,000×10 ⁻¹⁵ mol/(m ² ·s). -Pa) or less is more preferable.

The oxygen permeability in the present specification refers to a value measured by a differential pressure method according to JIS K 7126 at a temperature of 20° C. and a relative humidity of 80%.

The thickness of the substrate sheet is not particularly limited as long as it satisfies workability that can be easily cut with scissors or a cutting machine, and may be arbitrarily treated by a cosmetic treatment such as printing or embossing. good.

The mixed liquid to be applied forms an aromatic functional bonding layer and contains at least a bonding agent and a liquid fragrance.

As the bonding agent, it is preferable to use a pressure-sensitive adhesive or an adhesive such as polyurethane resin or (meth)acrylic resin, and from the viewpoint of preventing the low odor of the bonding agent and the fragrance functional bonding layer from protruding from the sheet end. Polyurethane resin is more preferable. In the present specification, the description of (meth)acrylic means at least one of acrylic and methacrylic.

As the polyurethane resin, it is possible to use, for example, a main agent containing a polyurethane polyol and a crosslinking agent obtained by mixing a curing agent containing a polyfunctional isocyanate.

The gel fraction of the polyurethane resin is preferably 50% or more, more preferably 60% or more, from the viewpoint of reducing stains due to uncrosslinked components. In the present specification, the gel fraction refers to a value calculated by impregnating toluene with a binder after cross-linking, measuring the mass of insoluble matter, and calculating a ratio with the mass before impregnation.

Here, the weight average molecular weight (Mw) of the polyurethane polyol contained in the main agent is preferably 10,000 or more, more preferably 20,000 or more, and from the viewpoint of obtaining a sufficient cohesive force. From the viewpoint of obtaining adhesive strength, it is preferably 500,000 or less, more preferably 400,000 or less, and further preferably 300,000 or less. In this specification, the weight average molecular weight (Mw) is a polystyrene-equivalent value measured by gel permeation chromatography (GPC method).

A solvent may be contained in the main component to appropriately dilute the polyurethane polyol. As the solvent, known ones such as methyl ethyl ketone, ethyl acetate, toluene, xylene and acetone can be used.

The polyurethane polyol contained in the main component has a urethane bond and a hydroxyl group capable of reacting with the polyfunctional isocyanate of the curing agent. The polyurethane polyol contained in the main agent is obtained mainly by reacting a polyol and a polyfunctional isocyanate in the presence of a catalyst.

Examples of the polyol for producing the polyurethane polyol include polyester polyol, polyether polyol, polycarbonate polyol, polycaprolactone polyol and the like.

Examples of the polyfunctional isocyanate for producing the polyurethane polyol include known aromatic polyisocyanates, aliphatic polyisocyanates, araliphatic polyisocyanates, alicyclic polyisocyanates, and the like.

Examples of the aromatic polyisocyanate include phenylene diisocyanate, diphenyl diisocyanate, toluylene diisocyanate, triisocyanate toluene, triisocyanate benzene, diphenyl ether diisocyanate, naphthylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate and triphenylmethane triisocyanate.

Examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, trimethylene diisocyanate, pentamethylene diisocyanate, propylene diisocyanate, butylene diisocyanate and trimethylhexamethylene diisocyanate.

Examples of the araliphatic polyisocyanate include diisocyanate dimethylbenzene, diisocyanate diethylbenzene, and tetramethylxylylene diisocyanate.

Examples of the alicyclic polyisocyanate include isophorone diisocyanate, cyclopentane diisocyanate, cyclohexane diisocyanate, methylene bis(cyclohexyl isocyanate), bis(isocyanatomethyl)cyclohexane and trimethylcyclohexyl isocyanate.

As the polyfunctional isocyanate contained in the curing agent, the same polyfunctional isocyanate used for producing the polyurethane polyol can be used. By blending this curing agent, the crosslinking density of the polyurethane resin can be controlled appropriately.

Examples of the combination of the main agent and the curing agent include a mode in which 0.5 to 40 parts by mass of the solid content is added to 100 parts by mass of the solid content of the polyurethane polyol as the main agent. It should be noted that, in addition to the main agent and the curing agent, within a range not departing from the gist of the present invention, an antioxidant, a corrosion inhibitor, a light stabilizer, an ultraviolet absorber, a heat stabilizer, a polymerization inhibitor, an inorganic or organic filler, and a metal. Additives such as powders, pigments, dyes, antistatic agents, plasticizers, and flame retardants may be optionally used.

As the (meth)acrylic resin, for example, a resin obtained by introducing an isocyanate curing agent into a (meth)acrylic polymer and crosslinking it can be used.

The gel fraction of the (meth)acrylic resin is preferably 50% or more, more preferably 60% or more, from the viewpoint of reducing stains due to uncrosslinked components.

The weight average molecular weight (Mw) of the (meth)acrylic polymer used is not particularly limited, but is preferably 300,000 to 2,000,000 because of high adhesive strength and high shearing force, and It is preferably 500,000 to 1,300,000. As the (meth)acrylic polymer, it is possible to use, for example, a polymer containing an alkyl (meth)acrylic acid ester as a main component and a polar monomer copolymerized therewith.

The (meth)acrylic acid alkyl ester is not particularly limited, but methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, methyl methacrylate, ethyl methacrylate, n- Examples thereof include butyl acrylate, isobutyl methacrylate, 2-ethylhexyl methacrylate, 2-hydroxyethyl acrylate, and 2-hydroxyethyl methacrylate. From the viewpoint of excellent low-temperature adhesiveness, n-butyl acrylate (Tg=Tg=Tg) having a low glass transition temperature (Tg). It is preferable to use -55°C) or 2-ethylhexyl acrylate (Tg=-70°C).

As the polar monomer copolymerized with the (meth)acrylic acid alkyl ester, a nitrogen-containing monomer, a hydroxyl group-containing monomer, an epoxy group-containing monomer, an unsaturated aliphatic carboxylic acid or the like can be used. The polar monomer acts as a crosslinking point when the acrylic polymer is crosslinked.

Examples of the nitrogen-containing monomer include N-vinylpyrrolidone, N-vinylcaprolactam, acryloylmorphone, acrylamide and methacrylamide.

Examples of the hydroxyl group-containing monomer include (meth)acrylic acid hydroxyalkyl ester, and the like. 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4 -Hydroxybutyl methacrylate and the like can be mentioned.

Examples of the epoxy group-containing monomer include glycidyl acrylate and glycidyl methacrylate.

Examples of unsaturated aliphatic carboxylic acids include acrylic acid, methacrylic acid, maleic acid, fumaric acid and itaconic acid.

The (meth)acrylic polymer can be produced by various known methods, and for example, a radical polymerization method such as a bulk polymerization method, a solution polymerization method or a suspension polymerization method can be appropriately selected. Examples of the polymerization initiator include azo-based polymerization initiators such as azobisisobutyronitrile (AIBN), peroxide compounds such as lauroyl peroxide and benzoyl peroxide (BPO), benzophenone-based initiators such as benzophenone, and 2-methyl. A thioxanthone type initiator such as thioxanthone and a benzoin ether type initiator such as benzoin ethyl ether can be used, but an azo type polymerization initiator such as azobisisobutyronitrile is particularly preferable from the viewpoint of polymerizability and the like. Then, the acrylic polymer produced by the above method can be dissolved in a solvent such as toluene, ethyl acetate, or methyl ethyl ketone to prepare an acrylic polymer solution.

Examples of the isocyanate-based curing agent include xylylene diisocyanate, tolylene diisocyanate, hexamethylene diisocyanate, trimethylolpropane tolylene diisocyanate, diphenylmethane triisocyanate, and the like.

Here, the amount of the curing agent blended is preferably 0.05 to 5 parts by mass, and 0.1 to 3 parts by mass based on 100 parts by mass of the (meth)acrylic polymer, from the viewpoints of adhesive properties, heat resistance, and moist heat resistance. A mass part is more preferable, and 0.2-2 mass parts is still more preferable.

Liquid fragrances are roughly classified into plant flowers, floral ones extracted from leaves, oriental animal-derived ones, citrus-derived fruit ones, and woody ones extracted from perfume. , Any of which can be used. Also, synthetic fragrances can be used. The liquid fragrance may be one kind or a combination of two or more kinds.

Typical examples of the floral system include rose, jasmine, lily of the valley, and the like. Typical examples of the oriental system include Ambergris, musk, civet, vanilla, myrrh, and frankincense. Typical examples of the fruit type include lemon, lime, orange, bergamot, mandarin, and other citrus type derived from aphids. Typical examples of woody type include sandalwood and patchouli.

For example, among the floral type, there are herb type fragrances that are said to have various effects such as calming the mood and obtaining good sleep depending on the scent, and can be suitably used. This type of fragrance includes rosehip, rosemary, bay leaf, hyssop, lemon palm, mint, peppermint, jasmine, basilico, oregano, marjoram, perilla, sesame, sage, savory, thyme, anise, inondo, dill, angelica, Cherville, coriander, honeywort, fennel, robbed, rabid, parsley, chives, leek, tarragon, lemon myrtle, borage, borage, capers, lemongrass, bay, bay leaf, laurel, lemon parbena, psyllium, curry leaf, mustard, ceiba, nasturtium. , Nasturtium, Masticha, Yarrow, Yarrow, Purple Valencia, Echinacea, Echinacea, Chamomile, Feverfew, Feverfew, Common dandelion, Dandelion, Betula vulgare, Wormwood, Tancha, Tanaceae, Strawberry, Strawberry, Butterbur, Butterpar , Catmint, Clary Sage, Onisalvia, Hawthorn, St. John's wort, Hypericum perforatum, Passiflora, Passionflower, Henruda, Valerian, Bay, Ylang-Iran.

The liquid fragrance contains an alcohol component, and as the alcohol component, octanol, decanol, 1-menthol, dl-menthol, isoeugenol, eugenol, geraniol, citronellol, cinnamyl alcohol, terpineol, benzyl alcohol, d-borneol, maltol. In addition to the above, aliphatic higher alcohols, aromatic alcohols and the like can be mentioned.

The content of the alcohol component in the liquid fragrance refers to the total amount when two or more liquid fragrances are used, and is preferably 55% by mass or less and 50% by mass or less from the viewpoint of maintaining aromaticity and aroma persistence. Is more preferable, and 45 mass% or less is further preferable. Examples of the lower limit of the content include 10% by mass or more, 15% by mass or more, and 20% by mass or more.

Further, the content of the alcohol component in the liquid fragrance is preferably 2 parts by mass or more, more preferably 10 parts by mass or more, with respect to 100 parts by mass of the bonding agent, from the viewpoint of maintaining aromaticity and aroma persistence. From the viewpoint of preventing the aromatic functional bonding layer from protruding from the end portion of the sheet, it is preferably 20 parts by mass or less, and more preferably 18 parts by mass or less.

The content of the liquid fragrance with respect to 100 parts by mass of the bonding agent is preferably 7 parts by mass or more, more preferably 10 parts by mass or more, and further preferably 15 parts by mass or more, from the viewpoint of fragrance persistence. The upper limit is, for example, 100 parts by mass or less, 80 parts by mass or less, and 50 parts by mass or less.

In addition, the mixed liquid may optionally contain other additives. Other additives include antioxidants, corrosion inhibitors, light stabilizers, UV absorbers, heat stabilizers, polymerization inhibitors, inorganic or organic fillers, metal powders, pigments, dyes, antistatic agents, plasticizers. Agents, flame retardants and the like.

The storage elastic modulus (G′) at 25° C. of the fragrance functional bonding layer formed by using such a mixed liquid is 0., from the viewpoint of preventing the fragrance functional bonding layer from protruding from the sheet end. 1 MPa or more is preferable, 0.15 MPa or more is more preferable, 0.2 MPa or more is further preferable, and from the viewpoint of flexibility, 1,000 MPa or less is preferable, 100 MPa or less is more preferable, and 10 MPa or less is further preferable. In addition, the storage elastic modulus (G′) of the aromatic functional bonding layer at 60° C. is preferably 0.001 MPa or more and 1 MPa or less from the viewpoint of use at high temperature.

In this specification, the storage elastic modulus (G′) is a value measured according to JIS K 7244. More specifically, using a dynamic viscoelasticity measuring device (manufactured by Japan Sebel Hegner, model number: MCR301), in a temperature range of −40° C. to 190° C., a temperature rising rate of 3° C./min and a frequency of 1 Hz are used. It is a value measured at 25° C. or 60° C.

In addition, the thickness of the fragrance functional bonding layer is preferably 3 μm or more, more preferably 10 μm or more, further preferably 12 μm or more, from the viewpoint of fragrance persistence, and the protrusion from the sheet end of the fragrance functional bonding layer. From the viewpoint of preventing the above, 500 μm or less is preferable, 250 μm or less is more preferable, and 100 μm or less is further preferable.

The drying process according to the present invention includes a drying process A and a drying process B. In the step of drying the sheet product, a method of using a drying device or the like to dry the sheet while applying a drying air is mentioned, but from the viewpoint of productivity, it is preferable to use the drying device immediately after coating. .. However, in a sheet product that uses liquid fragrance, if a drying device is used immediately after coating, only the surface layer of the coating liquid dries and skinning occurs, or the aromatic functional bonding layer is generated due to bumping of the coating liquid. The appearance may be deteriorated, such as bubbles being generated. Furthermore, when the solvent in the coating liquid is heated by the amount of heat required for drying or more, the aroma function of the liquid perfume itself may be impaired. In the production method of the present invention, since the drying step A is provided before performing the drying step B using a drying device, such a defect can be prevented and an aroma sheet having a good appearance can be produced.

The drying step A according to the present invention is a step of holding the sheet coated by the coating step in an atmosphere of 10 to 45°C at a wind velocity of less than 1 m/sec. In the drying step A, it is preferable that the drying air is not applied actively to the sheet by using a drying device or the like, and it is preferable that the sheet is substantially windless. The term "substantially no wind" includes conditions such as a wind speed of 0.1 m/sec or less.

From the viewpoint of productivity, the temperature of the drying step A is 10° C. or higher, preferably 20° C. or higher, and from the viewpoint of improving the appearance, it is 45° C. or lower, preferably 35° C. or lower, 30 C. or less is more preferable.

The time for performing the drying step A is not particularly limited, but is preferably 2 seconds to 25 seconds, more preferably 3 seconds to 20 seconds, and further preferably 4 seconds to 15 seconds.

As a specific example of the aspect of the drying step A, in the production of a sheet that is continuously transferred by a conveyor or the like, the room temperature in the manufacturing step is set so that the ambient temperature in the section in which the drying step A is performed becomes the above temperature. There is a mode in which the adjustment is performed and the interval between the coating device and the drying device is adjusted to the above-mentioned execution time.

The drying step B according to the present invention is a step of maintaining the air velocity of 1 m/sec or more in the atmosphere of 45 to 95° C. after the drying step A.

The time for performing the drying step B is not particularly limited, but is preferably 15 to 200 seconds, more preferably 25 to 150 seconds, and further preferably 35 seconds to 100 seconds.

From the viewpoint of raising the temperature of the sheet with a gradual temperature gradient, the drying step B is preferably an embodiment including a drying treatment by two or more drying zones including at least a first drying zone (first drying zone) and a final drying zone, A preferred mode is one in which the set temperature of the drying device is set to increase from the first drying zone to the final drying zone. In this case, the temperature difference between the first drying zone and the drying step A (first drying zone drying step A) is preferably 5° C. or higher, more preferably 10° C. or higher, from the viewpoint of productivity. From the viewpoint of preventing bumping and skinning of the liquid, 50°C or lower is preferable, and 40°C or lower is more preferable. Examples of the set temperature of the first drying zone include 45 to 60°C. It is preferable to set the subsequent drying zones so that the temperature of the first drying zone gradually increases. The final drying zone is preferably 75°C or higher, more preferably 80°C or higher from the viewpoint of removing the diluting solvent contained in the coating liquid, and 95°C or lower from the viewpoint of preventing volatilization of the aromatic component.

As the drying device used in the drying step B, a known drying device can be used. Examples of the known drying device include an oven, a hot air blower, a heating roll, a far infrared heater, a hot air circulation drying oven, and the like, and these can be used alone or in combination as necessary, and various embodiments can be used. Can be taken.

As the blowing means of the drying device, for example, a counter flow type can be used. The wind speed is not particularly limited as long as it is 1 m/sec or more, and a suitable range varies depending on the set temperature, but it can be set to 1 to 35 m/sec. For example, when the set temperature is lower than 65°C, 3 to 35 m/sec is preferable, 4 to 25 m/sec is more preferable, 5 to 20 m/sec is further preferable, and 1 to 25 m/sec when the set temperature is 65°C or higher. Seconds are preferable, 2 to 20 m/sec are more preferable, and 3 to 15 m/sec are further preferable. In the present specification, the wind speed refers to a value obtained by measuring the wind speed at a position of 3 cm above the coating liquid applied on the base material sheet using an anemometer. As the anemometer, a mini vane type digital anemometer (Anemometer MODEL1560/SYSTEM6243 manufactured by Nippon Kanomax Co., Ltd.) can be used.

In the manufacturing method of the present invention, other steps such as a cooling step and a bonding step can be optionally provided.

Here, the cooling step is a step of cooling the sheet after the drying step by a known means. If the sheet is rapidly cooled from the drying step, dew condensation may occur on the sheet, which may lead to deterioration of quality and contamination of production equipment. From the viewpoint of preventing this, the sheet after the drying step gradually becomes 10 to 30°C. It is preferable to cool to.

The bonding step is a step of bonding a base material sheet, a release sheet or the like on the aromatic functional bonding layer using a known bonding means after the drying step or the cooling step. For example, an aspect of an aroma sheet obtained by sticking a base material sheet will be described with reference to FIG. In the embodiment of FIG. 1, the fragrance sheet 1 includes two base material sheets 2. The base material sheet 2 is laminated in the thickness direction with the fragrance functional bonding layer 3 interposed therebetween. In this aspect, from the viewpoint of preventing the base sheet from being easily peeled off from the fragrance functional bonding layer 3, the adhesive strength of the fragrance functional bonding layer 3 is preferably 1 N/25 mm or more, more preferably 3 N/25 mm or more. .. Although not shown, as the adhesive strength in a mode in which the release sheet is bonded onto the fragrance functional bonding layer in the bonding step (that is, a mode in which a release sheet is used in place of the upper base sheet 2 in FIG. 1) Is preferably 0.003 to 0.3 N/25 mm from the viewpoint of easy peeling and the like.

The adhesive strength of the fragrance functional bonding layer is based on JIS K 6854-3, and two base material sheets adjacent to the fragrance functional bonding layer are pulled at a tensile speed of 200 mm/min in an environment of 23° C. and 50% RH. It is the peeling strength when the T-type peeling is performed under the condition of.

The manufacturing method of the present invention can be used not only for manufacturing the fragrance sheet of the embodiment shown in FIG. 1 but also for manufacturing the fragrance sheet as illustrated in FIGS. 2 and 3.

In the embodiment of FIG. 2, the fragrance sheet 1 includes three base material sheets 2. The base sheet 2 is laminated in the thickness direction between the sheets with the fragrance functional bonding layer 3 interposed therebetween.

In the embodiment of FIG. 3, the fragrance sheet 1 includes three base material sheets 2. The base material sheet 2 is laminated in the thickness direction with the fragrance functional bonding layer 3 interposed between the one sheet and the layer 4 other than the fragrance functional bonding layer interposed between the other sheets. Here, examples of the layer 4 other than the fragrance functional bonding layer include an adhesive layer and a bonding layer having no fragrance function, but are not particularly limited.

It should be noted that although not shown, various other modes are conceivable on the assumption that at least one fragrance functional bonding layer is provided. For example, in FIG. 3, the layers other than the fragrance functional bonding layer may have a multilayer structure, or the base material sheets may be directly laminated by fusion or the like. Further, the number of base material sheets is not limited to the above-mentioned aspect.

Preparation Example of Polyurethane Polyol 66.52 parts by mass of xylylene diisocyanate and polycarbonate polyol (Kuraray Polyol C-1015N manufactured by Kuraray Co., Ltd.) 98.56 in a four-necked flask equipped with a stirrer, a reflux condenser, a nitrogen inlet tube, and a thermometer. Mass parts, 2,2-dimethylolpropionic acid 27.89 parts by mass, and toluene 100 parts by mass were charged, and the temperature was gradually raised to 100° C. and the reaction was carried out for 4 hours. After confirming the remaining amount of isocyanate groups by titration, the mixture was cooled to 40° C., 100 parts by mass of ethyl acetate was added, 30 parts by mass of ethylenediamine was added dropwise for 1 hour, and the reaction was further performed for 1 hour to obtain a polyurethane polyol. .. The weight average molecular weight (Mw) of the obtained polyurethane polyol was 132,000, and the acid value was 30.0 mgKOH/g.

Preparation Example of Methacrylic Polymer 8 parts by mass of methyl acrylate, 75 parts by mass of n-butyl acrylate, 8 parts by mass of 2-ethylhexyl acrylate, 5 parts by mass of 2-hydroxyethyl acrylate, and 4 parts by mass of acrylamide were used as a weight average of constituent monomers. Polymerization was performed so that the molecular weight (Mw) was 1,100,000 to obtain a methacrylic polymer.

Examples 1-5, Comparative Examples 3-6
100 parts by mass of the polyurethane polyol prepared as described above was blended as a resin raw material to be a binder, and 25 parts by mass of isophorone diisocyanate was blended as a curing agent. Further, a liquid fragrance (a rose scent sample/alcohol component 30% by mass) was mixed in an amount of 40 parts by mass with respect to 100 parts by mass of the bonding agent to obtain a mixed liquid of the resin raw material and the liquid fragrance. The obtained mixed liquid was applied onto a polyethylene terephthalate resin sheet having a thickness of 12 μm using an applicator so that the thickness of the aromatic functional bonding layer after drying was 20 μm, and the drying step was performed under the conditions shown in Table 1. A was performed. After that, the drying step B is performed in an oven in which the first to fifth drying zones shown in Table 2 are set to remove the solvent, and the sheet is cooled to 28° C. so that dew condensation does not occur on the sheet, and the aroma functionality is obtained. The bonding layer was formed. An unstretched polypropylene resin sheet having a thickness of 25 μm was attached to the surface of the formed aroma functional bonding layer with a nip roller to prepare an aroma sheet. The curing condition of the obtained aroma sheet was 23° C. and 50% RH for 14 days.

Example 6
As a resin raw material to be a binder, 100 parts by mass of the methacrylic polymer prepared as described above was compounded in place of 100 parts by mass of the polyurethane polyol, and 0.4 part by mass of xylylene diisocyanate was compounded in place of 25 parts by mass of isophorone diisocyanate. Then, an aroma sheet was prepared in the same manner as in Example 1 except that the curing condition was 7 days.

Comparative Examples 1 and 2
An aroma sheet was prepared in the same manner as in Example 1 except that the drying step B was performed immediately after the coating step.

The storage elastic modulus and the adhesive strength of the fragrance functional bonding layer of Example 1 were measured by the above-described measuring method. The storage elastic modulus (G′) at 25° C. was 0.398 MPa, and the storage elastic modulus (G′ at 60° C. ') was 0.317 MPa, and the adhesive strength was 4 N/25 mm. In addition, the gel fraction of the polyurethane resin contained in the fragrance sheet of Example 1 as a binder was 94%.

The storage elastic modulus and the adhesive strength of the fragrance functional bonding layer of Example 6 were measured by the above-described measuring method. As a result, the storage elastic modulus (G′) at 25° C. was 0.217 MPa, and the storage elastic modulus (G′ at 60° C. ') was 0.145 MPa and the adhesive strength was 5 N/25 mm. The gel fraction of the methacrylic resin contained in the aromatic sheet of Example 6 as a binder was 83%.

The oxygen permeability of the base sheet used in each of the examples and comparative examples is polyethylene terephthalate (12 μm): 384×10 ⁻¹⁵ mol/(m ² ·s·Pa), unstretched polypropylene (25 μm): 11, It was 520×10 ⁻¹⁵ mol/(m ² ·s·Pa).

(Aroma persistence)
Each of the aroma sheets of Examples and Comparative Examples was cut into a size of 10 cm×10 cm, left standing for 24 hours in an environment of 60° C. and 95% RH, and then taken out, and then a weather meter (irradiation conditions: frame side xenon irradiation, illuminance: 70 W/m ² , temperature/humidity conditions: BPT; 65° C., 50%) After irradiation for 24 hours, whether the desired fragrance was obtained A total of 50 test subjects, 5 male and 5 female, performed odor determination by the three-point comparison odor bag method, and the determination results were evaluated as follows. The results are shown in Table 1.
⊚: All 48 to 50 people among 50 people can judge correctly.
Good: 43 to 47 out of 50 people can be correctly judged.
Δ: 40 to 42 out of 50 can be correctly judged.
×: Out of 50 people, the number of people that can be correctly judged is 39 or less.

(Uniformity of coated surface)
For each of the fragrance sheets of Examples and Comparative Examples, sampling was performed at a size of 1 m×1 m immediately after the fragrance sheet was manufactured, and the coated surface was visually confirmed by a method of reflecting light using a three-wavelength fluorescent lamp. It was evaluated as. The results are shown in Table 1.
⊚: There is no noticeable fluctuation other than the texture of the base material used for the fragrance sheet and the ripples in the flow direction during coating.
◯: There is no noticeable fluctuation other than the texture of the base material used for the fragrance sheet and the ripples in the flow direction at the time of coating, and the ripples in the flow direction are slightly conspicuous, but this is an obstacle to practical use. Absent.
Δ: In addition to the texture of the base material used for the fragrance sheet and the ripples in the flow direction at the time of coating, there are fluctuations, which are somewhat difficult to put into practical use.
X: In addition to the texture of the base material used for the fragrance sheet and the ripples in the flow direction during coating, remarkable fluctuations were observed and there was no practical use.

(Presence of bubbles)
For each of the fragrance sheets of Examples and Comparative Examples, 5 pieces were sampled at a size of 1 m×1 m immediately after the fragrance sheet was manufactured, and the size and number of bubbles were visually observed by a method of transmitting light using a three-wavelength fluorescent lamp. After confirmation, the average number of bubbles per sheet was calculated and evaluated as follows. The results are shown in Table 1.
A: The average number of bubbles of 0.5 mm ² or more is less than 1/m ² .
◯: The average number of bubbles of 0.5 mm ² or more is 1 cell/m ² or more and less than 3 cells/m ² , and there is no problem in use.
Δ: The average number of bubbles of 0.5 mm ² or more is 3 cells/m ² or more and less than 8 cells/m ² , which is somewhat difficult to put into practical use.
X: The average number of bubbles of 0.5 mm ² or more is 8 cells/m ² or more, which is completely impractical.

From the comparison between each Example and Comparative Examples 1 and 2, it can be seen that the aroma persistence and the appearance are inferior unless the drying step A is performed. Further, from the comparison between each Example and Comparative Examples 3 and 4, it can be seen that when the temperature is out of the specified temperature range of the drying step A, the fragrance persistence and the appearance are inferior. Further, from the comparison between each Example and Comparative Examples 5 and 6, it is understood that when the temperature is out of the specified temperature range of the drying step B, the fragrance persistence and the appearance are very poor.

On the other hand, in each of the examples in which the drying steps A and B were carried out, it can be seen that the fragrance persistence and the appearance were excellent. Note that, among the examples, particularly excellent results were obtained for Examples 1 and 6 in which the drying step A was performed at a temperature of 30° C. and a drying time of 10 seconds.

The invention is in no way limited by the embodiments and examples described above. Various embodiments can be adopted without departing from the scope of the present invention.

Since the fragrance sheet obtained by the production method of the present invention has good fragrance persistence and appearance, it can be used for various articles. For example, it can be suitably used as a fragrance used in a closet, a storage case, a wallet, a business card holder, or the like, or an article with a scent provided with a fragrance sheet. Examples of the scented article provided with the fragrance sheet include a mouse pad having an aromatic property, a signboard and an advertisement having a repellent effect.

1 Fragrance Sheet 2 Base Sheet 3 Fragrance Functional Bonding Layer 4 Layers Other than Fragrance Functional Bonding Layer

Claims (7)

A method for producing an aromatic sheet, comprising: a coating step of coating a mixed liquid containing a binder and a liquid flavor on a base sheet; and a drying step of drying the sheet coated by the coating step. , The drying step holds the coated sheet in an atmosphere of 10 to 45° C. at a wind speed of less than 1 m/sec, and 45 to 95° C. at a wind speed of 1 m/sec or more after the drying step A. A method for producing an aroma sheet, which comprises a drying step B of maintaining the atmosphere under the atmosphere. The manufacturing method according to claim 1, wherein the drying step A is performed for 2 to 25 seconds. The drying step B includes a drying treatment by two or more drying zones including at least a first drying zone and a final drying zone, the set temperature of the first drying zone is 45 to 60° C., and the setting of the final drying zone is set. The method according to claim 1 or 2, wherein the temperature is 75 to 95°C. The manufacturing method according to claim 1, wherein the liquid flavor contains 2 to 20 parts by mass of an alcohol component with respect to 100 parts by mass of the bonding agent. The manufacturing method according to claim 1, wherein the bonding agent contains a polyurethane resin or a (meth)acrylic resin. The manufacturing method according to any one of claims 1 to 5, wherein a content of the liquid fragrance is 7 to 100 parts by mass relative to 100 parts by mass of the bonding agent. The manufacturing method according to claim 1, wherein the liquid flavor contains an alcohol component in an amount of 10 to 55% by mass.

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