JP6788271B2 - Method for manufacturing sustained-release film - Google Patents

Description

The present invention mainly relates to a method for producing a sustained-release film that exerts effects such as aroma, deodorization, insect repellent, and repellent.

Conventionally, various sustained-release films or sustained-release sheets have been devised in order to exert effects such as fragrance, deodorization, pest control, and repellent on the external space. The sustained-release film or sustained-release sheet retains the above-mentioned functional agents having functions such as aroma, deodorant, insect repellent, and repellent, and the effect is exhibited by continuous volatilization of the functional agents for a certain period of time. It is something that is demonstrated.

Such a sustained-release film or a sustained-release sheet is disclosed, for example, as a pest repellent adhesive sheet for repelling pests against animals, and a pest repellent layer containing a volatile pest repellent component. , A permeation control layer provided on one side of the pest repellent layer for controlling the permeation of the pest repellent component, and a permeation control layer provided on the other side of the pest repellent layer for substantially permeating the pest repellent component. A pest that is provided with a non-barrier layer and a pressure-sensitive adhesive layer that is provided on the opposite side of the barrier layer to the animal's skin and / or clothing. A repelling adhesive sheet (see, for example, Patent Document 1) is known.

Further, for example, a multilayer film having a sustained-release function (see, for example, Patent Document 2), which comprises a storage layer containing an active substance and a release control layer for controlling the release rate of the active substance, is known. Is. The storage layer is provided on the base material layer (paragraphs 0008 to 0009 of the same document).

Further, in a scented sheet in which a microencapsulated fragrance-containing layer is provided on at least one surface of the base material and a protective layer is provided on the fragrance-containing layer, the fragrance-containing layer is thermoplastic. A scented sheet in which a resin is used as a binder and the protective layer is made of an aqueous resin, and the scent-containing layer is a microencapsulated scented sheet and a urethane resin is known (a scented sheet). For example, see Patent Document 3.)

Utility Model Registration No. 3149381 JP-A-4-331141 JP 2012-6262

Currently, in order to reduce the manufacturing cost of a sustained-release film or a sustained-release sheet and improve versatility, it is required to secure and improve the sustained-release property while reducing the number of layers of the film used. ing.

The pest repellent sheet (sustained release sheet) according to Patent Document 1 includes a pest repellent layer, a permeation control layer laminated on the pest repellent sheet, a barrier layer, and an adhesive layer. The pest repellent component (hereinafter referred to as a functional agent) is retained in the pest repellent layer on the barrier layer as a base material, and the release of the pest repellent component is controlled by the permeation control layer. Further, the multilayer film according to Patent Document 2 includes a storage layer containing an active substance (that is, a functional drug) and a release control layer that controls the release rate of the active substance. Here, it is disclosed that the storage layer contains a base material.
Based on the above, the sustained-release sheets disclosed in Patent Documents 1 and 2 both have a holding layer for holding a functional drug and a control layer for controlling the release thereof on a base material. It has a three-layer structure based on the structure provided with the above. Therefore, it is desirable that the number of layers of the sheet, which is the basic configuration, can be further reduced.

Further, in the sustained-release sheet according to Patent Document 3, since the protective layer is formed of an aqueous resin, the protective layer is dissolved by water, and the fragrance-containing layer is exposed only when the surface is rubbed. It has a mechanism to destroy the microencapsulated fragrance and generate an odor. That is, the microcapsules of the functional layer are destroyed on the premise that the protective layer is dissolved by water. Therefore, when the protective layer is dissolved, it has a basic structure of two layers, a base material and a fragrance-containing layer, and thus it is considered to have a two-layer structure.

However, according to the sustained-release sheet, in the absence of the protective layer, the microcapsules are easily destroyed and the duration of the odor is shortened. On the other hand, unless the microcapsules are destroyed, no odor is generated. Therefore, it has a drawback that the generation and persistence of odors tend to be unstable. Therefore, as disclosed in the invention of Patent Document 3, it can be said that the protective layer is indispensable, and in the end, the configuration of the three layers including the protective layer has to be adopted as the basic configuration.

Further, in the invention according to Patent Document 3, the fragrance-containing layer is composed of a microencapsulated fragrance and a urethane resin, so that the microencapsulated fragrance is uniformly contained in the urethane resin binder in the fragrance-containing layer. Disclose that it can be dispersed, has higher water resistance, and can exert the function of odor generation more sustainably. However, on the premise of using microcapsules, the microcapsules may not be destroyed constantly, and as described above, there is a drawback that the generation and persistence of odors tend to be unstable.

Further, as in Patent Document 3, in the configuration using microcapsules, heating is performed in the manufacturing process (for example, a general masterbatch method (a method of heating and dissolving a functional substance in a resin). According to this, it is possible to suppress the evaporation of functional chemicals against heating of about 200 ° C to 400 ° C), but on the contrary, when microcapsules are not used, highly volatile chemicals Since it evaporates during production, it is very difficult to form a sustained-release sheet or a sustained-release film in which the functional agent is transpired and the basic composition is two layers.

Furthermore, the fact that the sustained-release sheet is thinner, that is, formed as a sustained-release film, and that the sustained-release film can be formed as transparent, can be used for more purposes and leads to increased versatility. It is considered more desirable.

The present invention has been made in view of the above circumstances, and is a sustained-release film having a basic structure of two layers, which enables stable sustained-release of a drug for a long period of time without using microcapsules. The invention seeks to solve the provision of an excellent method for producing a sustained-release film , which can adjust the sustained-release property according to the purpose, reduce the production cost, and improve the versatility. Make it an issue.

Further, in addition to the above problems, the present invention aims to provide a method for producing a sustained-release film having transparency, which is an object to be solved by the present invention.

In the present invention, the functional agent is prepared by a first step of preparing a drug mixed solution in which polyurethane and a functional agent having exudability to polyurethane are dispersed in a solution, and a casting method on a substrate made of synthetic resin. In a method for producing a sustained-release film, which comprises a second step of forming a dispersed polyurethane layer and a third step of drying a laminated film of the base material and the polyurethane layer, the solution in the first step is , The organic solvent is composed of at least one of methyl ethyl ketone, dimethylformamide, and toluene, and the weight ratio of polyurethane in the drug mixture solution using only the organic solvent as a solvent is 14 weight. A method for producing a sustained-release film of % to 26% by weight is used as a means for solving the above-mentioned problems.
Here, the casting method is a solution-type coating method, and refers to a method in which a solution is applied in a thin thickness to form a film.

The present invention also provides a method for producing a sustained-release film, which is characterized in that the functional agent is at least one of an air freshener, a deodorant, an insect repellent, and a repellent, on the premise of the constitution of the above invention. , As a means for solving the above problems.

Further, in the present invention, on the premise of the constitution of any one of the above inventions, a method for producing a sustained-release film characterized in that the base material and the polyurethane layer are transparent is used as a means for solving the above-mentioned problems. To do.

Further, in the present invention, on the premise of the configuration of any of the above inventions, the base material made of the synthetic resin is polyethylene terephthalate, and the thickness of the base material is 40 μm to 75 μm, or the base material made of the synthetic resin is made of the synthetic resin. Production of a sustained-release film in which the base material is a polar film having any one of polyacrylic acid ester, polymethacrylic acid ester, and polycarbonate as a main composition, and the thickness of the base material is 50 to 150 μm. The method is used as a means for solving the above-mentioned problems.

Further, the present invention is premised on the configuration of any of the above inventions, and has an additional step after the third step, and the additional step functions on the polyurethane layer in which the functional agent is dispersed by a casting method. A method for producing a sustained-release film, which is a step of laminating a polyurethane layer containing no sex agent, is a means for solving the above-mentioned problems.

Further, the present invention comprises a base material and a polyurethane layer provided on the base material by any of the above manufacturing methods, and the polyurethane layer is provided with a functional agent having exudability to the polyurethane layer. It is possible to provide a sustained-release film characterized by being provided.

Further, in the present invention, on the premise of the constitution of the sustained-release film by any of the above-mentioned production methods, the base material is polyethylene terephthalate or a derivative thereof, polyacrylic acid ester, polymethacrylic acid ester, or polycarbonate. A sustained-release film characterized by being a polar film having a main composition can be provided.

Further, in the present invention, on the premise of the constitution of any of the above-mentioned sustained-release films by any of the above-mentioned production methods, a region in which the functional agent is dissolved or dispersed and the above-mentioned functional agent are dissolved or dispersed in the polyurethane layer. It is possible to provide a sustained release film characterized by having a region that does not .

According to the present invention, the first step of preparing a drug mixed solution in which polyurethane and a functional drug having exudability to polyurethane are dispersed in the solution, and the above-mentioned functionality by a casting method on a substrate made of synthetic resin. In the method for producing a sustained-release film, which comprises a second step of forming a polyurethane layer in which a drug is dispersed and a third step of drying a laminated film of the base material and the polyurethane layer , the said in the first step. The solution is composed of at least one of methyl ethyl ketone, dimethylformamide, and toluene, and the solvent is only an organic solvent, and the weight ratio of polyurethane in the drug mixture solution using only the organic solvent as a solvent is By adopting a method for producing a sustained-release film having a content of 14% by weight to 26% by weight , the polyurethane layer is provided with the functions of both a drug holding layer and a control layer, and the film can exhibit sustained-release properties. It is possible to realize a film that can exhibit the function associated with sustained release, which is thinner and more uniform than before.

Then, in the production method, the functional agent is retained in a polyurethane layer that also serves as a drug holding layer and a control layer by holding at least one of an air freshener, a deodorant, an insect repellent, and a repellent. It is possible to realize a thin-layer film that is homogeneous at the molecular level and can release odorants, insect repellents, and repellents slowly.

Further, on the premise of the configuration of any of the above inventions, by making the base material and the polyurethane layer transparent, the above-mentioned effects can be obtained and the film can be realized as a transparent film, so that it is conspicuous even if it is attached to the place of use. However, it is possible to realize a thin-layer film that allows a drug having the function to be released slowly in a very wide range of applications.

Further, on the premise of the configuration of any of the above inventions, the base material made of the synthetic resin is polyethylene terephthalate, and the thickness of the base material is 40 μm to 75 μm, or the base material made of the synthetic resin is It is a polar film mainly composed of polyacrylic acid ester, polymethacrylic acid ester, and polycarbonate, and the thickness of the base material is 50 to 150 μm, thereby ensuring compatibility between the base material and the polyurethane layer. , A sustained-release film having excellent durability can be provided.

Further, on the premise of the configuration of any of the above inventions, an additional step is provided after the third step, and the additional step is performed by casting the functional agent onto the polyurethane layer in which the functional agent is dispersed. By arranging the step of laminating the polyurethane layer that does not contain the compound, the polyurethane layer that is finally laminated becomes one layer, and the functional agent in the polyurethane layer is held on the lower side of the polyurethane layer. It is possible to provide a sustained-release film which is controlled so as to delay the sustained-release as a whole and enables a sustained-release film for a longer period of time. In addition, it is possible to control the thickness, sustained release amount, and service life according to the purpose.

Further, by any of the above manufacturing methods, a base material and a polyurethane layer provided on the base material are provided, and the polyurethane layer is provided with a functional agent having exudability to the polyurethane. By using the characteristic sustained-release film, the polyurethane layer can function as both a drug holding layer and a control layer, and the effect of the functional drug can be exhibited, and at the molecular level of the functional drug and polyurethane. It is possible to provide a thin layer film having excellent durability due to its good compatibility.

Further, in the present invention, the main composition of the base material is polyethylene terephthalate or a derivative thereof, polyacrylic acid ester, polymethacrylic acid ester, or polycarbonate, on the premise of the thin-layer film by any of the above-mentioned production methods. Therefore, it is possible to ensure the durability of the sustained-release film as a whole due to the good compatibility between the base material and the polyurethane layer.

Further, the present invention is based on the constitution of the invention relating to any of the above-mentioned sustained-release films by any of the above-mentioned production methods, and a region in which the functional agent is dissolved or dispersed and the said functional agent are dissolved in the polyurethane layer. Alternatively, since the sustained-release film is characterized by having a region that does not disperse, the effects of the invention relating to any of the above-mentioned sustained-release films are exhibited, and until the functional agent is released to the outside. It is possible to control the sustained release according to the purpose by changing the distance of.

(A) An explanatory cross-sectional view showing a layer structure of a sustained-release film according to Example 1 of the present invention, and (b) an explanatory cross-sectional view showing a layer structure of a sustained-release film according to Example 2 of the present invention. (A) An explanatory cross-sectional view showing a layer structure of a sustained-release film according to Example 3 of the present invention, and (b) an explanatory cross-sectional view showing a layer structure of a sustained-release film according to Example 4 of the present invention. It is explanatory cross-sectional view which shows the layer structure of the sustained-release film which concerns on other Examples of this invention. It is a simplified figure which shows a part of the casting apparatus used in the manufacturing method of the sustained-release film which concerns on Example 1 of this invention, and its process. It is a simplified figure which shows a part of the casting apparatus used in the manufacturing method of the sustained-release film which concerns on Example 2 of this invention, and its process. It is a simplified figure which shows a part of the casting apparatus used in the manufacturing method of the sustained-release film which concerns on Example 4 of this invention, and its process.

Examples of the present invention will be described below. The present invention is not limited to the following examples, and includes various design / setting changes, modifications, and the like within the scope of the technical idea disclosed by the present invention.

The method for producing the sustained-release film 1 according to Example 1 of the present invention will be described below.
The production method according to this embodiment includes a solution generation step (first step) of preparing a drug mixture solution in which polyurethane and a functional agent are dispersed in a solvent, and polyethylene terephthalate using the produced drug mixture solution as a base material. It has a laminating step (second step) of laminating on top and a heating and drying step (third step) for volatilizing the solvent component. Hereinafter, each step will be described in order (see FIGS. 1A and 4).

In the first step, a drug mixed solution 2X prepared by dissolving or dispersing polyurethane and the functional drug 20 in a solvent is prepared.
By adding the functional agent 20 and toluene to a 30% by weight solution of polyurethane containing MEK (methylethylketone) and DMF (dimethylformamide) as solvents, and dissolving and dispersing them, the functional agent 20 uses MEK, DMF and toluene as solvents. It is assumed that a drug mixed solution 2X containing 23% by weight of polyurethane containing the above is obtained.
The weight ratio of each component (MEK: DMF: toluene) constituting the drug mixed solution 2X is 40:35:25.

In this example, the temperature at the time of melting or dispersion is about 40 ° C.
As the functional drug 20, a drug having a function according to the intended use is used. Functions according to the application can be, for example, fragrance, deodorant, insect repellent / repellent, and the like. The amount of the functional drug 20 added can be determined by controlling the degree of efficacy of the functional drug and the sustainable period of use.

Further, the functional agent 20 in the present invention is required to have exudability due to a homogeneous dispersion state at the molecular level with polyurethane. In addition, the functional agent 20 exhibits various functions (for example, fragrance, deodorant, insect repellent / repellent, etc.) according to the functional agent 20 by slowly releasing or staying on the film surface together with exhibiting exudative property. Will be done.

The following is an example of using an air freshener, a deodorant, and an insect repellent / repellent that function as the functional agent 20.

As an example of the above-mentioned air freshener exhibiting sustained-release property and exudative property to polyurethane, a functional agent 20 based on a middle fragrance (middle note) can be used.
The amount of the fragrance added can be 13 to 14% by weight based on the total weight of the polyurethane and the functional agent 20.

As an example of the deodorant exhibiting the sustained-release property and the exudative property to polyurethane, a solvent-soluble type functional agent 20 made of persimmon astringent (tannin) can be used. The amount of the deodorant added can be 5 to 15% by weight based on the total weight of the polyurethane and the functional agent 20.

As an example of the above-mentioned insect repellent / repellent that exhibits sustained-release property and exudative property to polyurethane, a functional drug 20 using menthone glycerin acetal can be used. The amount of the insect repellent / repellent added can be 1 to 15% by weight based on the total weight of the polyurethane and the functional agent 20.

The fragrance as the functional agent 20 preferably contains a so-called middle fragrance (middle note) as a main component, but can also be a base fragrance (last note). Further, if a predetermined residual amount can be secured during the process, it is possible to include a top fragrance (top note) in a part thereof.

Examples of the functional agents having insect repellent / repellent (hereinafter referred to as insect repellents or repellents) include evaporative pyrethroids such as empentrin and derivatives thereof, pyrethroid agents and derivatives thereof, DEET, and synthetic agents such as picaridin. , Natural chemicals such as plant-derived components such as mentandiol or derivatives thereof can be used.

As shown above, a drug mixed solution 2X in which each functional drug 20 is dissolved or dispersed as an appropriate amount is prepared.

In this example, the above-mentioned chemical mixture solution 2X is laminated (film formation) on the base material 3 made of polyethylene terephthalate (PET).
The base material 3 has a film thickness of about 50 μm in this example. The base material 3 is in a winding state, and as shown in FIG. 4, the base material 3 is sequentially fed from the end portion to the charging portion through the supply side roller 72 in the casting device.

Further, as shown in FIG. 4, the drug mixed solution 2X is introduced into the charging section. The chemical mixture solution 2X introduced into the charging section is flowed into the base material 3 by adjusting the thickness with a roller or a blade, and is sent to the low temperature dryer H in a state where the base material 3 and the chemical solution mixed solution are laminated. Be done.

After the laminating treatment shown above, the film in which the base material 3 of the polyethylene terephthalate and the polyurethane layer 2 are laminated is dried. In this embodiment, the average temperature is set to about 80 ° C. to 120 ° C. for about 40 seconds (that is, by passing a transport path of about 12 to 15 m at a speed of 20 m / min).
By the drying treatment, the MEK (methyl ethyl ketone), DMF (dimethylformamide), and toluene are volatilized, and the base material 3 and the polyurethane layer 2 are surely bonded to each other.

In this embodiment, by forming a 5 μm polyurethane layer on the 50 μm base material 3 by the casting method by the above steps, a two-layer sustained-release thin film is formed as a whole (FIG. 1 (a)). reference.).

The sustained-release film 1 is formed colorless and transparent by binding both the polyethylene terephthalate of the base material 3 and the polyurethane layer 2.
By using the casting method, the thickness can be increased to about 5 μm to 20 μm in one treatment.
The sustained-release film 1 thus obtained is obtained as a product by being wound up by a winding roller 73 after the heat treatment is completed.

As described above, since the present invention is basically composed of two layers of the base material 3 and the polyurethane layer 2 formed on the base material 3 and holding and controlling the functional agent 20. Not only can it be a very thin film, but it can also simplify the manufacturing process. Further, by applying the casting method to the method for producing the sustained-release film 1, it is possible to realize a thinner film.

Then, on the premise of the basic configuration, further lamination is possible as shown below. Even in this case, since the functional agent 20 can be basically retained and controlled only by one layer excluding the base material, even if further lamination is performed, the conventional sustained-release film having the same function is obtained. There is an advantage in that the total number of layers can be reduced in comparison.

Further, as Example 2, which is a modification of Example 1, the polyurethane layer 2 can be laminated twice by the casting method by repeating the second to third steps after the first step. For example, as shown in FIG. 5, the first casting device and the second casting device may be arranged in series, and the processing by the first casting method may be performed, and then the processing by the second casting method may be performed. it can.
In the manufacturing process, after the first treatment, the polyurethane layer 2 can be further polymerized on the polyurethane layer 2 laminated in the first treatment (see FIG. 1 (b)). ..
By this treatment, the polyurethane layer 2 laminated in the first time and the polyurethane layer 2 laminated in the second time are formed as one layer as a whole.
As a result, in the second embodiment, when the polyurethane layers 2 are stacked twice, the thickness of the polyurethane layers 2 can be set to about 10 μm to 40 μm.

Further, as Example 3, in the first laminated film forming treatment in Example 2, as shown in FIG. 1A, a lower layer in which the functional agent 20 is dissolved and dispersed is formed to form the second laminated film. In the treatment, the state in which the functional agent 20 is not dissolved, that is, the solution containing polyurethane before the functional agent 20 is added can be laminated as it is as a film. Further, in this case, it is also possible to add only toluene to the solution containing polyurethane without adding the functional agent 20.
By the production method, a region in which the functional agent is dissolved or dispersed and a region in which the functional agent is not dissolved or dispersed are formed, and only in the lower layer (base material side) of the polyurethane layer 2 finally formed as one layer. The functional agent 20 can be dissolved and dispersed (see FIG. 2A).

Further, the thickness of the layer (lower layer 2b) in the first laminated film forming treatment, the thickness of the layer (upper layer 2a) in the second laminated film forming treatment, and the type of the functional agent 20 in the first laminated film forming treatment. The sustained release property can be controlled by the amount and the like.

Further, Example 4 in which a step of adding another layer is added to the manufacturing method which is the basic configuration of Examples 1 to 3 is shown below.

As shown in FIG. 6, the first cast device 7A and the second cast device 7B are arranged in series by the same method as in the second embodiment, and the polyurethane adhesive is used in the second cast device 7B which is the treatment on the rear side. 5 was laminated, and after heat treatment, it was wound by a winding roller 73 while being pressed by a pressure roller 71 together with a non-woven fabric layer 6 (or other decorative material layer) led out from a supply container 74 to impart design. A sustained-release film according to Example 4 can be obtained.

As shown in FIG. 3A, the sustained-release film 1 according to Example 4 produced by the above steps has a polyurethane layer 2 on a base material 3 and has a polyurethane layer 2 on the polyurethane layer 2. A polyurethane-based adhesive 5 is applied thereto, and a non-woven fabric layer 6 is laminated on the polyurethane-based adhesive 5.

As the polyurethane adhesive 5, for example, polyols and isocyanates can be used. With this configuration, the polyurethane-based adhesive 5 has an affinity with the polyurethane layer 2 located below the polyurethane layer 2 and is in a mixed state, and through the polyurethane-based adhesive layer 5A formed by the polyurethane-based adhesive 5, the polyurethane-based adhesive 5 is mixed. The functional agent 20 can be sustained-release, and its sustained-release rate is controlled to be more delayed. Further, the non-woven fabric layer 6 itself has the effect of improving the decorativeness.

Further, as shown in FIG. 3B, by using the manufacturing process of the sustained-release film 1 according to the fourth embodiment and using the release paper 8 instead of the non-woven fabric layer 6 or the decorative layer, when not in use. It is possible to significantly suppress the sustained release in.

In addition, exudation and sustained release can be significantly increased by cutting the paper pattern 8 into small pieces, peeling the paper pattern 8 and then storing the small pieces in a container such as a bag with a barrier property. It is possible to suppress it.

In the sustained-release film 1 according to the present embodiment, the polyurethane and the functional agent 20 are dispersed as a solution before the heat treatment and are homogeneous at the molecular level. Therefore, the release paper 8 or the barrier property It is possible to significantly suppress the exudability by blocking and sealing the external space with a bag or the like. As a result, sustained release when not in use can be significantly suppressed.

As described above, the function of the functional agent 20 can be, for example, an air freshener, a deodorant, an insect repellent, a repellent, or the like. On the other hand, the functional agent 20 is conditioned on having exudability to polyurethane.

In the above examples, polyethylene terephthalate was used as the base material, but the polyethylene terephthalate may contain some other composition as long as the main composition is polyethylene terephthalate.

Further, the base material according to the present invention is not limited to the above examples, and for example, a polar film having any one of polyacrylic acid ester, polymethacrylic acid ester, and polycarbonate as a main composition can be used.
In this case, the polyethylene terephthalate used as the base material preferably has a thickness of about 40 μm to 75 μm. Further, the acrylic resin-based film and the polycarbonate-based film are all preferably about 50 to 150 μm.

As the polyurethane, in addition to general ester-based polyurethanes, ether-based polyurethanes having excellent water resistance, carbonate-based polyurethanes having excellent heat resistance, chemical resistance, and water resistance can be used. As the ester-based material, for example, poly 1,6-hexamethylene adipate, polycaprolactone polyol, or the like can be used as the polyol as a raw material for the polyurethane. Further, as the ether type, for example, polytetramethylene glycol or the like can be used. Further, as the carbonate type, for example, polycarbonate diol or the like can be used. Moreover, these are examples and do not prevent the use of other polyurethanes.

The functional agent 20 may be any as long as it can be dissolved or dispersed in the mixed solution, and not only a single functional agent 20 but also a plurality of functional agents 20 can be added. Further, when a plurality of functional agents 20 are introduced, the agents may have a plurality of different functions or may have the same functions.

As shown in the above Examples, it is assumed that the functional agent 20 is mixed in an amount according to the function and the component, but in the present invention, the functional agent 20 is contained regardless of the above Examples. On the condition that the polyurethane and the functional agent 20 can be mixed up to 15% by weight based on the total weight of the functional agent 20.
If it exceeds 15% by weight, a large amount of perfume evaporates even during drying (generally 80 ° C. to 120 ° C.), resulting in a large loss and a large tendency that it becomes difficult to maintain the shape of the film. is not.

The compounding weight ratio of polyurethane in the drug mixed solution is 23% by weight in the above-mentioned example, but the present invention is not limited to the above-mentioned example.
For example, the compounding weight ratio of polyurethane in the drug mixed solution can be 14% by weight to 26% by weight, more preferably 16 to 26% by weight. When the compounding weight ratio is less than 14% by weight, the fluidity becomes high (viscosity is low), and it diffuses carelessly, making uniform drying difficult, and wrinkles are likely to occur. On the other hand, if it exceeds 26% by weight, the fluidity is lowered (the viscosity is increased), the diffusion is remarkably suppressed, and as a result, a problem that streaky irregularities are easily generated on the surface is likely to occur.

In Example 1, a mixed solvent of MEK, DMF, and toluene was used as the solvent for dissolving the polyurethane, and the weight ratio of each component in the mixed solution of MEK, DMF, and toluene (MEK: DMF: toluene). ) Is 40:35:25, but the present invention is not limited to the above embodiment, and the weight ratio can be arbitrarily changed.
Further, it is not always necessary to use all of MEK, DMF, and toluene, and at least one of them may be used.

Further, in the above-mentioned Example 4, it is disclosed that the pressure roller 71 is used to press the non-woven fabric layer 6 or the other decorative material layer together with the pressure roller 71 to impart designability, but the present invention has the same structure. It is not limited, and for example, in the process, when the design is not imparted, it is possible to wind it together with the paper pattern without applying pressure.

Further, in the present invention, the solvent is not limited to MEK, DMF, and toluene, and a solvent having a polarity suitable for dissolving polyurethane can be used. As an example, cyclohexanol can be used instead of DMF.

Further, in the above-mentioned example, a method of separately adding toluene to a solution of polyurethane in MEK and DMF was used, but the present invention is not limited to the example and all of MEK, DMF and toluene are dissolved in advance. It is also possible to add polyurethane and a functional agent to the product.

On the other hand, when the mixed solvent is finally obtained by mixing all of MEK, DMF and toluene as in Example 1, the boiling point difference of each component of MEK, DMF and toluene is reduced. It has the advantage that each component can be volatilized more quickly.

As shown above, in the present invention, the polyurethane and the functional agent 20 are dissolved at low temperature to realize uniform dispersion at the molecular level in the solution, and the casting method is used for a short time in the low temperature dryer H. By performing the above treatment, volatilization of the functional agent was suppressed and a film was formed on the base material, whereby the excellent sustained-release film 1 was thinned as a whole and the holding layer and the control layer were shared. realizable.

The following tests were conducted to confirm the range and effect of the sustained release of the sustained-release film and the effectiveness of each function of the functional drug 20.
(Test 1) Sustained release test-Test method: A square test piece of 20 cm x 20 cm was prepared, hung in a room at about 25 ° C. and left to stand, and the weight was measured for each elapsed day. The residual rate of the functional drug was calculated.
As the functional agent 20, A: middle note fragrance which is an air freshener, B: menthone glycerin acetal, and C: persimmon astringent (tannin) were used.
As the thickness of the sustained-release film used as the test piece, three types of films [1] to [3] were used. The film [1] has a drug-containing layer of 15 μm, the film [2] has a drug-containing layer of 30 μm, and the film [3] has a polyurethane layer of 5 μm laminated on the drug-containing layer of 30 μm.

以上から、柿渋（タンニン）を機能性薬剤２０として用いた場合に、２００日を超える徐放性性能を極めて高い水準で保持できることが判明した。また、機能性薬剤２０であるＡ（ミドルノート）、Ｂ（ＭＧＡ）においても、薬剤含有層が１５μｍであるにもかかわらず、持続的に（直線的に）３０日以上の良好な徐放性を得ることができた。 -Test results (1) Test piece: Film [1]: For the drug-containing layer 15 μm thickness, the correspondence between the number of days elapsed and the residual amount is shown in Table 1 below, and the graph is shown in Table 2 below. In the table, "-" indicates unmeasured.

From the above, it was found that when persimmon astringent (tannin) was used as the functional agent 20, the sustained-release performance of more than 200 days could be maintained at an extremely high level. Further, also in A (middle note) and B (MGA), which are functional drugs 20, even though the drug-containing layer is 15 μm, the sustained release property is continuously (linearly) for 30 days or more. I was able to get.

以上から、薬剤含有層を３０μｍとした場合には、機能性薬剤２０であるＡ（ミドルノート）、Ｂ（ＭＧＡ）において、上記薬剤含有層が１５μｍと比較して、徐放機能を維持できる期間が２倍程度に向上することが判明した。 (2) Test piece: Film [2]: For a drug-containing layer with a thickness of 30 μm, the correspondence between the number of days elapsed and the residual amount is shown in Table 3 below, and the graph is shown in Table 4 below.

From the above, when the drug-containing layer is set to 30 μm, the period during which the sustained-release function can be maintained in the functional drugs 20 A (middle note) and B (MGA) as compared with 15 μm. Was found to improve about twice.

以上から、５μｍのＰＵ（ポリウレタン）層を積層することによって、徐放機能の維持が薬剤含有層３０μｍのみのフィルムに比較して向上することが判明した。 (3) Test piece: Film [3]: With respect to the drug content of 30 μm + the polyurethane layer of 5 μm, the correspondence between the elapsed days and the residual amount is shown in Table 5 below, and the graph is shown in Table 6 below.

From the above, it was found that by laminating a 5 μm PU (polyurethane) layer, the maintenance of the sustained-release function is improved as compared with a film having only a drug-containing layer of 30 μm.

以上から、フィルム［２］はフィルム［１］に比較して経過日数６０日までにおいて高い芳香機能が得られることが判明した。また、フィルム［３］において６０日を超えて安定した防虫機能が得られ、９０日に至っても比較的良好な芳香機能を保持できることが判明した。 (Test 2) Functionality test A: Aromatic function test using air freshener (middle note) -Test method: For the above films [1] to [3] having each thickness, the strength of the volatile aroma is determined by humans. Judgment by smell. Judgment criteria are: ◎: strong scent, ○: medium scent, △: weak scent, ×: extremely weak scent.
-Test results: The table below shows the relationship between the number of days elapsed and the identification results.

From the above, it was found that the film [2] can obtain a higher aromatic function than the film [1] up to 60 days after the lapse of days. Further, it was found that the film [3] had a stable insect repellent function for more than 60 days and could maintain a relatively good aroma function even for 90 days.

以上から、フィルム［２］はフィルム［１］に比較して経過日数６０日までにおいて高い防虫効果が得られ、特に経過日数３０日までにおいて極めて高い防虫効果が得られるとともに、９０日に至ってもある程度の防虫効果が得られることが判明した。
また、フィルム［３］において９０日を超える安定した良好な防虫効果が得られることが判明した。 B: Insect repellent function test using insect repellent ・ Test method; For the above films [1] to [3] having each thickness, in accordance with the invasion prevention method of the anti-tick performance test method for JIS L 1920 textile products, mites. Judge the effectiveness of using. As a judgment criterion, ⊚: repellent rate of 90% or more, ◯: repellent rate of 70 to 90%, and Δ: repellent rate of 50 to 70% are identified.
-Test results: The table below shows the relationship between the number of days elapsed and the identification results.

From the above, the film [2] has a higher insect repellent effect up to 60 days than the film [1], and particularly has an extremely high insect repellent effect up to 30 days, and even after 90 days. It was found that a certain degree of insect repellent effect can be obtained.
Further, it was found that a stable and good insect repellent effect for more than 90 days can be obtained in the film [3].

以上から、フィルム［１］を用いて９０日以上の非常に優れた消臭率を保持できることが判明した。 C: Deodorant function test using deodorant ・ Test method: Film [1] is measured by the detector tube method with ammonia as the target malodor in accordance with the efficacy test method of "Voluntary Standards for Aroma Deodorant Deodorant". And judge the effectiveness. As a judgment criterion, ⊚: deodorant rate of 90% or more, ◯: deodorant rate of 70 to 90%, Δ: deodorant rate of 50 to 70%.
-Test results: The table below shows the relationship between the number of days elapsed and the identification results.

From the above, it was found that the film [1] can be used to maintain a very excellent deodorizing rate for 90 days or more.

以上より、ＰＥＴ（ポリエチレンテレフタレート）とポリウレタンとの結着性が非常に優れていることが判明した。
尚、ＰＥ（ポリエチレン）及びＰＰ（ポリプロピレン）は、ポリウレタンとの結着性において剥離性を有することから本願発明の構成としては適合しないことが判明した。 (Test 3) Bonding test A comparison experiment was conducted on the binding property of other resins to polyurethane.
-Test method: Each sheet of A4 plate prepared by laminating each of the following resins (1) to (3) on polyurethane was observed using a testing machine to see if the binding surface was peeled off by a predetermined load.
-Each resin used as a base material for comparison (1) Polyethylene terephthalate (PET)
(2) Polypropylene (PP)
(3) Polyethylene (PE)
-Test results: The table below shows the relationship between the number of days elapsed and the identification results.

From the above, it was found that the binding property between PET (polyethylene terephthalate) and polyurethane is very excellent.
It was found that PE (polyethylene) and PP (polypropylene) are not suitable for the configuration of the present invention because they have peelability in terms of binding property to polyurethane.

1 Sustained release film 2 Polyurethane layer 2X Chemical mixture solution 2a Upper layer 2b Lower layer 20 Functional chemicals 3 Base material (polyethylene terephthalate layer, etc.)
5 Polyurethane adhesive 5A Polyurethane adhesive layer 6 Non-woven fabric layer (nonwoven fabric)
7 Casting device 7A 1st casting device 7B 2nd casting device 70 Input section 70a Input section roller 71 Pressurizing roller 72 Supply side roller 73 Winding roller 74 Supply container 8 Paper pattern H Low temperature dryer

Claims (6)

The first step of preparing a drug mixed solution in which polyurethane and a functional agent having exudability to polyurethane are dispersed in a solution, and polyurethane in which the functional agent is dispersed on a synthetic resin substrate by a casting method. In a method for producing a sustained-release film, which comprises a second step of forming a layer and a third step of drying a laminated film of the base material and the polyurethane layer .
The solution in the first step uses only an organic solvent as a solvent.
The organic solvent comprises at least one of methyl ethyl ketone, dimethylformamide, and toluene.
A method for producing a sustained-release film, wherein the polyurethane compounding weight ratio in the chemical mixture solution using only the organic solvent as a solvent is 14% by weight to 26% by weight . The method for producing a sustained-release film according to claim 1, wherein the functional agent is at least one of an air freshener, a deodorant, an insect repellent, and a repellent. The method for producing a sustained-release film according to claim 1 or 2, wherein the base material and the polyurethane layer are transparent. The method for producing a sustained-release film according to claim 1, 2 or 3, wherein the synthetic resin base material is polyethylene terephthalate or a derivative thereof, and the thickness of the base material is 40 μm to 75 μm. The claim is characterized in that the base material made of the synthetic resin is a polar film having any one of polyacrylic acid ester, polymethacrylic acid ester, and polycarbonate as a main composition, and the thickness of the base material is 50 to 150 μm. Item 3. The method for producing a sustained-release film according to Item 1, 2 or 3. It has an additional step after the third step and has
Claim 1, 2, 3, 4, or claim 1, wherein the additional step is a step of laminating a polyurethane layer containing no functional agent on a polyurethane layer in which the functional agent is dispersed by a casting method. 5. The method for producing a sustained-release film according to 5.

Images