JPH04122434A - Porous body containing functional substance and its preparation - Google Patents

Abstract

PURPOSE:To obtain a porous body having the function possessed by a functional substance in addition to buffering properties and damping properties by adding the functional substance to a silicone gel having many voids formed thereto. CONSTITUTION:Particles having higher solubility, shrinkability or heat- disappearing properties as compared with a silicone gel are mixed with the raw solution before curing of the silicone gel and a functional substance is further mixed therewith. After the raw solution is cured, the particles are eluted by a solvent, or shrunk by drying or removed by heating to obtain a porous body having voids formed to the regions where the particles are present and containing the functional substance. As the functional substance, a deodorant, an aromatic agent, a pesticide, an insecticide, an insect attracting agent, an insect repelling agent and an moisture absorbing agent can be used. The silicone gel can be made porous by adapting a drying/shrinking method, an elution method, a microwave heating method or a thermal removing method. The drying/shrinking method is one drying and shrinking the swollen particles mixed with the silicone gel to remove the same.

Description

[Detailed Description of the Invention] (Purpose of the Invention) <Industrial Application Field> The present invention is a gel-like substance that has excellent properties as a material for cushioning, vibration isolation, packaging, etc., by improving its properties. The present invention relates to a gel-like porous body that is porous and has other functions such as deodorization and fragrance, and a method for producing the same.

<Background of the Invention> In recent years, attention has been paid to silicone gel for its cushioning and vibration-proofing properties, and silicone gel is being widely used as soles of shoes, cushioning pads for various sports equipment, insulators for OA equipment, and special packaging. Under these circumstances, the present inventor has developed a method for producing a porous body of a gel-like substance and a porous body of silicone gel for the purpose of reducing the weight, improving air permeability, and reducing costs. On the other hand, the idea of incorporating a deodorizing agent into an open-cell foam has already been disclosed (Japanese Unexamined Patent Application Publication No. 1983-1999).
(No. 135061) This idea was to improve air circulation and maintain a large effective surface area of the deodorizer. Therefore, conventional open-cell foams are not necessarily suitable for use as cushioning materials for areas that are subject to relatively large stress, such as shoe soles and packaging materials, and they have other functions such as cushioning properties, deodorizing functions, and insect repellent functions. It was hoped that the material would emerge.

<Technical matters attempted to be developed> The present invention was made in response to such demands, and by incorporating a functional substance into a porous body of silicone gel, it is possible to improve cushioning and vibration-proofing properties. In addition, we attempted to develop a porous material that also has the functions of functional materials.

(Structure of the invention) <Means for achieving the object> That is, the porous body containing a functional substance, which is the first invention according to the present application, has a dinocone gel formed with a large number of pores, and
It is characterized by containing a functional substance.

In addition to the above-mentioned requirements, the porous body containing a functional substance, which is the second invention related to the present application, has the above-mentioned requirements. It is characterized by being made of one or more substances selected from the following.

Furthermore, the third invention of the present application, a method for producing a porous body containing a functional substance, includes adding to a raw solution of silicone gel before hardening,
A step of mixing granules that are more soluble or shrinkable or heat-disappearing than silicone gel, a step of mixing one functional substance, a step of hardening the stock solution, and then eluting the granules with a solvent or shrinking them by drying. The method is characterized by having a step of removing the particles or disappearing by heating to form pores in the areas where the particles were present.

Furthermore, the method for manufacturing a porous body containing a functional substance, which is the fourth invention of the present application, includes adding a silicone gel that has a larger dielectric loss coefficient than the stock solution and does not easily dissolve into the stock solution before hardening into the silicone gel stock solution. A step of adding a volatile liquid to emulsify it, a step of mixing a functional substance, and dielectric heating of the emulsified stock solution to vaporize and expand the particles of the easily volatile liquid and crosslink and harden the stock solution. The method is characterized by having a step of causing the process to take place.

These inventions attempt to achieve the above object.

<Action of the Invention> In the present invention, since a functional substance is contained in the silicone gel formed by forming a large number of pores, this product has not only the cushioning and vibration-proofing properties of the porous silicone gel, but also the silicone gel which has many pores. It has the functions of other functional substances.

<Example> Hereinafter, the constituent elements of the present invention will be specifically explained. First, silicone gel is composed of dimethylsiloxane component units, and diorganopolysiloxane (hereinafter referred to as component A), which is the stock solution of silicone gel used in linear formula [1]: RR'2810 (R22810), S IR'
2R-[]][However, R is an alkenyl group, and R1
is a monovalent hydrocarbon group having no aliphatic unsaturated bond, R2 is a monovalent aliphatic hydrocarbon group (at least 50 mol% of R'' is a methyl group, and when it has an alkenyl group, its content is 10 mol% or less),
n is the viscosity of this component at 25°C of 100-100
．． 000 cSt], the viscosity at 25°C is 5000 cSt or less, and the silicone gel has at least three hydrogen atoms directly bonded to the 81 atoms in one molecule. The ratio (molar ratio) of the total amount of alkenyl groups contained in the A component to the total amount of hydrogen atoms directly bonded to the Si atoms in the siloxane (B component) is from 0.1 to This is an addition-reactive silicone copolymer obtained by curing a mixture adjusted to have a viscosity of 2.0. To explain this silicone gel in more detail, the above A component has a linear molecular structure, and the alkenyl groups R at both ends of the molecule are S in the B component.
It is a compound that can form a crosslinked structure by adding with a hydrogen atom directly bonded to an i atom. The alkenyl group present at the end of the molecule is preferably a lower alkenyl group, and in consideration of monoreactivity, a vinyl group is particularly preferred.

Furthermore, R1 present at the end of the molecule is a monovalent hydrocarbon group having no aliphatic unsaturated bonds, and specific examples of such groups include alkyl groups such as methyl groups, propyl groups, hexyl groups, etc., and phenyl groups. Also, mention may be made of fluoroalkyl groups. In the above [Formula 11], R2 is a monovalent aliphatic hydrocarbon, and specific examples of such groups include alkyl groups such as methyl, propyl and hexyl groups, and lower alkenyl groups such as vinyl groups. The following groups can be mentioned.

However, at least 50 mol% of R2 is a methyl group, and when R2 is an alkenyl group, the amount of the alkenyl group is preferably 10 mol% or less. If the amount of alkenyl groups exceeds 10 mol %, the crosslinking density becomes too high and the viscosity tends to increase. Also, n is 2 of this A component.
Viscosity at 5°C is usually 100-100,000c
S t , preferably 200-20,000c S
It is set within the range of t. The B component above is 1
, is a crosslinking agent for component S], and the hydrogen atom directly bonded to the ring atom adds to the alkenyl group in component A to harden component A. Component B should have the above action.
Component B can have various molecular structures such as linear, branched, cyclic, or network-like. Further, in addition to hydrogen atoms, an organic group is bonded to 81 atoms in component B, and this organic group is usually a lower alkyl group such as a methyl group. Furthermore, the viscosity of component B at 25°C is usually less than 5000cS, preferably 500cS or less.
cSt or less. Examples of such components include organohydrogensiloxane with both molecular ends capped with triorganosiloxane groups, copolymers of diorganosiloxane and organohydrogensiloxane, tetraorganotetrahydrogencyclotetrasiloxane, HR '. Copolymer siloxane consisting of SiO]72 units and 5i04/2 units, and HR'□Si0]7
2 units and R', S i O]/2 units and S10 4/2
Examples include copolymer siloxanes consisting of units. However, in the above formula, R' has the same meaning as above. The ratio of the total molar amount of alkenyl groups in component A to the total molar amount of hydrogen atoms directly bonded to Si in component B is usually 0.1 to 2.0, preferably 0°1. It is manufactured by mixing and curing component A and component B so that the ratio is within the range of ~1.0. The curing reaction in this case is usually carried out using a catalyst. The catalyst used here is preferably a platinum-based catalyst, such as finely ground elemental platinum, chloroplatinic acid, platinum oxide,
Mention may be made of complex salts of platinum and olefins, platinum alcoholades, and complex salts of chloroplatinic acid and vinylsiloxic acid. Such a complex salt is usually used in an amount of 0.1 ppm or more (in terms of platinum, hereinafter the same), preferably 0.5 ppm or more, based on the total weight of components A and B. There is no particular restriction on the upper limit of the amount of the catalyst, but for example, if the catalyst is in liquid form or can be used as a solution, an amount of 200 ppm or less is sufficient. Here, compounds such as sulfur, phosphorus, tin-based compounds, and amines easily react with the platinum-based catalyst, so cross-linking
These are so-called catalyst poisons that inhibit curing, and specifically include sulfur-based compounds such as potassium sulfate, ammonium sulfate,
Sulfates such as ammonium persulfate, sodium persulfate, sodium sulfite, hydrosulfide, sulfur hydroxyamine,
Sulfur, carbon disulfide, sodium sulfoxylate (Rongalite), thioglycolic acid and its derivatives such as butyl thioglycolate, mercaptan compounds such as β-mercaptopropionic acid, thioacetic acid, thiourea, sulfonate sulfate ester salts Examples include surfactants such as. Examples of phosphorus compounds include phosphoric acid and its salts such as ammonium phosphorous phosphorous acid, hypophosphorous acid pyrophosphoric acid sodium metaphosphate, sodium tripolyphosphate, and trimedelphosphate dialkyldithio. Furthermore, tin compounds include various tin chlorides and tin oxides, as well as rhodan salts and stannous sulfate, and amine compounds include iminobispropylamine, triethylamine, 3-gelaminopropylamine, and tetramethylethylenediamine. , 3-methoxypropylamine, and the like. Component A, component B, and catalyst as described above are mixed and left at room temperature or cured by heating to produce the silicone gel used in the present invention.

When curing by heating, the heating temperature is usually 50 to 160℃.
It is °C. The Ginocone gel thus obtained is JIS K (K-2207-1980 50g load)
The penetration, measured at , usually has a value of 5 to 250.

Such a hardness of the silicone gel allows the amount of the above-mentioned A component to form a crosslinked structure with the hydrogen atoms directly bonded to Si in the B component. Alternatively, it can be adjusted by adding in advance a silicone oil having methyl groups at both ends in an amount within the range of 5 to 75% by weight to the resulting silicone gel. Dinocone gel can be prepared as described above, or commercially available gels can also be used. Examples of commercially available products that can be used in the present invention include CF50
27, TOUGH - 3 TOUGH
-4TOUGL(-5TOUGH-
6 ()-manufactured by Dow Corning Silicone Company) and X32
-902/cat 1300 (manufactured by Shin-Etsu Chemical Co., Ltd.), F250-1. 21 (manufactured by Nippon Unica Co., Ltd.). In addition, the above A component,
In addition to component B and the catalyst, pigments, curing retardants, flame retardants, fillers, etc. can be blended within the range that does not impair the properties of the dinocone gel. Examples of such materials that may be used include Phyllite (registered trademark) manufactured by Hhon Phyllite Co., Ltd., Expancel (registered trademark) sold by the same company, and Matsumoto Microspheres (manufactured and sold by Matsumoto Yushi Pharmaceutical Co., Ltd.). I can give an example. This point will be explained in detail in the microwave heating method.

Next, the functional substance contained in the silicone gel will be explained. As functional substances, deodorizers, fragrances, insect repellents, insecticides, insect attractants, and insect attractant moisture absorbers can be applied.

Deodorizers include activated carbon, zeolite, and cristobalite.
There are amion, aluminum orthophosphate, an aggregate of particles in which zinc oxide, titanium dioxide, and water molecules are tightly bound (see JP-A-63-54-9'35), and aniko plant extract. Zeolite adsorbs polar molecules such as water and ammonia and sulfur-based gases such as hydrogen sulfide well, whereas activated carbon has a relatively low adsorption capacity for low-molecular substances. Furthermore, activated carbon exhibits excellent adsorption capacity at low temperatures, whereas zeolite has high adsorption capacity at relatively high temperatures and low concentrations. In applications where there is relatively little moisture, this product simultaneously adsorbs moisture and odors, so it can be expected to be effective in combination with a deodorizer and a moisture absorbent to be described later. Cristobalite is a type of silicate mineral created by diatoms, a type of algae, becoming diatomaceous earth over a long period of time and then being burned by volcanic magma, and its main component is silicon dioxide. The adsorption rate of ammonia is high, but that of hydrogen sulfide is somewhat low. Amion is a powder made of natural inorganic substances, and has the ability to deodorize through biological actions in the soil and through the physical and chemical actions of rocks and minerals. Aluminum orthophosphate adsorbs ammonia amines well. An aggregate of particles made of tightly bound zinc oxide, titanium dioxide, and water molecules is a fine powder deodorizer with a particle size on the order of microns or submicrons, and it is white in color while activated carbon is black. Suitable for use in hygienic areas. In addition to this type of deodorizer,
A combination of zinc oxide, aluminum oxide, and silicon oxide (see JP-A No. 63-246167), a combination of titanium oxide, zinc oxide, magnesium oxide, and calcium oxide (see JP-A-63-1.8544 and JP-A-63-1.8544); 1986-1.8306
(see issue 5). Aniko is a greenish-blue liquid whose main component is ferrous sulfate and L-ascorbic acid as an oxidation inhibitor. Examples of plant extracts include flavanols and flavonols extracted from plants of the Camellia family, typified by tea, and extracts from coniferous and broad-leaved trees. Among these various deodorizing agents, activated carbon, zeolite, cristobalite amidino, aluminum orthophosphate, and aggregates of particles in which zinc oxide, titanium dioxide, and water molecules are tightly bound are all powders, so they can be applied to the present invention as they are. but,
Even in the case of liquid Anico or plant extracts, they can be applied by absorbing them into a suitable powder.

As the fragrance, natural fragrances, synthetic fragrances, mixed fragrances, etc. may be used, in addition to powdered fragrances obtained by spray-drying and powdering an emulsified fragrance.

As an insect repellent, baladichlorobenzene, a combination of aresnin and piperonyl butoxide, amidino, etc. can be used.

Examples of insecticides include fenitrothion for ticks,
There are organic phosphoric acids such as fenthion, pyrethroid compounds that collectively include natural pyrethrins and synthetic pyrethrin compounds, and these can be used.

Insect attractants are odorous substances that act on the sense of smell of insects to attract them, and insect pheromones and other naturally occurring components contained in plants and the like that exhibit attracting properties are known. Insect pheromones are substances that are produced within the insect's body and are excreted to the outside, causing specific behaviors in other individuals of the same species. There are alarm pheromones that are comparable to danger signals.

Insect attractants have an effect opposite to that of insect attractants, and include, for example, N,N-dimethyl-m-t-ramide, which does not have a strong repellent effect against tropical shimmering forces.

As a moisture absorbent, calcium chloride dihydrate, ShiJiki gel,
Quicklime etc. can be used.

Next, a method for manufacturing a porous body containing such a functional substance will be explained. To make silicone gel porous, a drying shrinkage method, an elution method, a microwave heating method, a heating disappearance method, etc. can be applied.

First, a method for manufacturing a porous body containing a functional substance by applying a drying shrinkage method will be described. The drying shrinkage method is a method in which the swollen particles mixed in the silicone gel are dried and shrunk to remove traces of the swollen particles. To explain this method in detail, the swollen particles 2 are, for example, spherical particles in a water-containing gel state formed by combining sodium alginate with calcium ions to form water-insoluble calcium alginate on the surface or inside the surface. was used. The sodium alginate used here is a representative substance of alginate, which is a substance that forms the cell membranes of brown algae such as kelp, casino, and arame, and is an emulsion stabilizer, strengthening agent,
Used as a mold release agent, etc. This substance is an extremely highly viscous colloidal substance with strong hydrophilic properties, dissolves well in both cold and hot water, and has the property of forming an extremely viscous and uniform solution. When metal salts such as aluminum, barium calcium, copper, iron, button, zinc, and nickel are added to this solution, water-insoluble alginates are formed.

This water-insoluble alginate is in a hydrogel state immediately after being taken out of the aqueous solution, so when it dries, water evaporates and it shrinks significantly. The drying shrinkage method utilizes such shrinkage properties of sodium alginate, and specific examples will be shown below. First, prepare a 1% sodium alginate aqueous solution and a 1% calcium chloride aqueous solution in a large beaker, and use a microtube pump P to suck up the sodium alginate into the duplex and drop it into the total calcium chloride aqueous solution C.

In this way, the dropped particles are formed into a spherical shape by water pressure.
One by one, it settles, and at the same time it becomes insolubilized from the surface, and gradually becomes insolubilized to the inside, becoming swollen particles 2 of hydrous gel of calcium alginate. Although it depends on the concentration of sodium alginate and the diameter of the tube, particles with an average diameter of 4 mm were obtained in the example, so they were taken out of the aqueous solution, washed with water, and drained appropriately. The swollen granules 2, the functional substance 2a, and the silicone gel stock solution are mixed together. In the examples, A component SA and B component S were adjusted so that the weight ratio of the granules to the silicone gel stock solution was 1:1. Divide and mix. Next, mix A component SA and B component Sll, pour this mixture onto a glass plate 3 provided with 5 mm thick spacers on all sides, overlap the glass plate 3 from above, and heat this to 80°C. By leaving it in a heated furnace for 50 minutes, the A component SA and the B component S 11 react and the whole is cured, yielding a silicone gel sheet 1 in which the swollen particles 2 are dispersed. Next, heat the heating furnace 1. OO'
After raising the temperature to C, removing the upper and lower glass plates, and leaving it for 3 hours, the swollen particles 2 of calcium alginate dry and shrink as shown in FIG. 1(g), and the swollen particles 2 in the silicone gel sheet 1 Hole 4, which is a trace of removal, exists in the area where
are formed, and particles of calcium alginate that have been dried and shrunk adhere to the pores 4 as fine particles 5 having a diameter of 0.5 mm or less. By washing away the dried and shrunken fine particles 5 of calcium alginate with water, a porous body containing the functional substance of the present invention can be obtained. Incidentally, in this example, the adjacent pores 4 are in a state of continuity with each other, so a method of washing them away with water can be adopted, but when the mixing rate of the swollen particles 2 is low, the pores 4 are not continuous. Fine particles 5 cannot be washed with water. In such cases, adjacent pores can be formed continuously by, for example, soaking in aqueous ammonia, lowering the concentration of sodium alginate, or using other materials with high volume shrinkage. .

Next, a method for manufacturing a porous body containing a functional substance by applying an elution method will be described. The elution method is a method in which soluble particles are mixed into a silicone gel and cured, and then the particles are eluted in a solvent to form traces. To explain this method specifically, commercially available expanded polystyrene poles 7 with a diameter of about 3 mm are used as soluble particles, and the expanded polystyrene poles 7 are mixed with the silicone gel stock solution in a volume ratio of 2:3. Barrel A component SA, B
Mix in component S H.

At this time, an appropriate functional substance 2a is also mixed.

Then, A component SA and B component S 11 are mixed, and the thickness is 10
A silicone gel sheet with a thickness of 10 mm was poured onto a glass plate 3 with a 10 mm spacer placed on each side, and a glass plate was placed on top. Get 1. This state is almost the same as the example using the drying shrinkage method, but in the case of this method, one Styrofoam pole 7 floats because the specific gravity of the Styrofoam pole 7 is significantly smaller than the specific gravity of the silicone gel. It is unevenly distributed in the second layer of the sheet 1. Next, this sheet 1 is immersed in a vat filled with toluene T, which is a solvent for expanded polystyrene. If left in this state for 2 hours, the silicone gel will swell slightly and the expanded polystyrene pole 7 will dissolve in toluene T, and as shown in Figure 2(f), the area where the expanded polystyrene pole 7 was Voids 4 are formed, thereby obtaining a porous body containing the functional substance of the present invention. In this example, in the upper layer of the sheet 1, the adjacent pores 4 are continuous with each other, but in the lower layer, the polystyrene foam poles 7 were not present, so the layer was made of only silicone gel. Become. Incidentally, such a porous body can be applied, for example, when the pores 4 are present only on the side that comes into contact with the human body, and when the pores are not present on the side that does not come into contact with the human body for purposes such as reinforcement. Of course, the pores 4 may be formed throughout the silicone gel by adjusting the amount of Styrofoam poles 7 mixed in or by selecting other materials as the soluble particles.

In addition, in this example, since the expanded polystyrene pole 7 was selected as a granule, toluene T was used as the solvent, but the solubility constant (
Soluhilit,y Parameter) is 9
．． It is also possible to select 9 or more solvents and select the granules according to this solvent. The reason why a solvent fe having a solubility constant of 9.9 or more is selected is that if the solubility constant is less than this, the silicone gel may be greatly swollen or eroded. Among the solvents that can be selected from this point of view, the most suitable one is water, and in this case, it is necessary to select water-soluble particles. Examples include sodium polyacrylate, polyvinyl alcohol, methylcellulose, carboxymethylcellulose, polyethylene oxide, bovinylpyrrolidone, acrylic acid amide, glue, gelatin, casein, polypeptide funori, agar, sodium alginate, sodium chloride, glucose, sucrose, and natural polysaccharides. Examples include pullulan, xanthan gum, starch, and sodium ascorbic acid. on the other hand,
Examples of solvents with a solubility constant of 9.9 or more outside the aqueous layer include acetone ethanol, methanol, etc. Examples of solvents that can be dissolved in these include polydonyl alcohol methyl cellulose, ethyl cellulose, water-soluble nylon, shellac,
Examples include styrene. In addition, when the substance of the 5 grains is starch, an enzyme solution may be used in water as a solvent. Examples of enzymes include amylase, maltase, pepsin, trypsin, nirepsin, glucose, fructase, and the like. Here, as a second example of the elution method,
A method for manufacturing a porous body containing a functional substance by selecting water as a solvent with a solubility constant of 9.9 or more and applying sodium chloride as granules in accordance with this solvent will be described.

First, the sodium chloride used was a commercially available crystal with a substantially uniform cubic shape of about 0.4 mm. A component SA and B component S are mixed so that the weight ratio of this sodium chloride and the stock solution of dinocone gel is 2:1.
Component A, component B, S, a catalyst, and a suitable functional substance 2a are further mixed, poured into a cylindrical mold, and cured in an upright position.

In addition, in order to remove air taken in during mixing,
It is desirable to perform vacuum degassing before curing. If the amount of the silicone gel stock solution is more or less than the sodium chloride, the sodium chloride will naturally harden during curing and will gradually accumulate from the bottom of the silicone gel stock solution, surrounding it with the silicone gel. It hardens in a state where it is filled with the gel undiluted solution. Alternatively, if pressed from above and below during this time, excess silicone gel stock solution relative to sodium chloride will overflow from between the spaces as if being squeezed out, and the silicone gel stock solution will harden with an appropriate amount of silicone gel stock solution existing between the sodium chloride spaces. Therefore, if it is left for one hour at 80° C., component A SA and component B Sll will react, and a cured product in which sodium chloride is deposited almost densely inside will be obtained. still,
When there is more silicone gel stock solution, a layer consisting only of silicone gel will be formed on a part of the surface layer.

In addition, if the specific gravity ratio between sodium chloride and the silicone gel stock solution is about 2 to 1 as in the example, a layer consisting only of silicone gel will not be formed on the surface layer, and the entire layer will be a layer of silicone gel in which sodium chloride is dispersed. Become. On the other hand, if the amount of sodium chloride increases, it becomes difficult to mix with the silicone gel stock solution and vacuum defoaming, and at the same time, the number of pores occupied by sodium chloride increases, resulting in a thinner network structure in the finished state. You can get something. In practice, the weight ratio of the weight of sodium chloride to the silicone gel stock solution is preferably about 1.5:1 to 4:1, preferably about 2:1. Next, the cured silicone gel with sodium chloride dispersed therein is removed from the mold, sliced into pieces of appropriate thickness, for example, every 10 mm, and placed in a bath in which warm water is being stirred. Then, after boiling is repeated while changing the hot water several times, the hot water is drained and the water is dried. Pores, which are traces of removal, are formed in the areas where sodium chloride was present in the silicone gel, forming open-celled porous holes. A textured sheet is obtained. Generally, a skin layer tends to be formed on the hardened part that comes into contact with the mold, and this inhibits the elution of sodium chloride. If sodium chloride is eluted, the internal sodium chloride will be exposed and the elution will be faster.

Next, a method for manufacturing a porous body containing a functional substance by applying a microwave heating method will be described. In this microwave heating method, an easily volatile liquid with a large dielectric loss coefficient is dispersed in a silicone gel, and after the gel hardens, this liquid is dielectrically heated in a high-frequency electric field to raise the temperature and vaporize and expand the liquid. At the same time, the dinocone gel stock solution is cross-linked and cured. This method will be described below with reference to specific examples. First, as an easily volatile liquid, it is a substance that does not contain substances that are catalyst poisons, has a dielectric loss coefficient larger than that of the gel stock solution, and can be mixed and stirred to form an emulsion using the unhardened stock solution as a dispersion medium, and is relatively Choose a liquid that evaporates easily. Examples of such liquids include water, ethyl alcohol, methyl alcohol, and the like. The reason for selecting a substance with a larger dielectric loss coefficient than the gel stock solution is that in dielectric heating by applying high frequency, the product of the dielectric constant ε and the dielectric constant tangent tan δ, that is, the larger the dielectric loss coefficient, the faster the material will be heated. This selective heating property means that the pre-curing stock solution is heated faster than cross-linking and curing, which means that the heat is transferred to the surrounding pre-curing stock solution or the curing stock solution, and the easily volatile liquid itself vaporizes and expands. This is because it is essential for securing and forming pores in the crosslinked and hardened structure. In order for a readily volatile liquid to be able to form an emulsion during mixing and stirring, it is desirable that it not dissolve in the stock solution before hardening and that its specific gravity be close to this. In this example, water is used as such an easily volatile liquid, and water is mixed in the form of an emulsion into a mixture of components SA, B components S11, catalyst, etc. into a silicone gel stock solution barrel. It is desirable to mix water into each of the A component SA and the B component S11, and then mix the whole thing again. Further, at this time, an appropriate functional substance 2a is mixed. In order to obtain stable characteristics, it is preferable to remove air taken in during mixing, but this can be done by leaving the mixture under reduced pressure or vacuum for a while. In addition, in this example, silicone gel adjusted to have a penetration degree of 40 when cured normally was used.A component SA, B component S I + 45 g each
58 of each water W was mixed in, stirred well to disperse the whole into an emulsion, and then added the A component SA and the B component S.
8 is mixed and poured into a cylindrical mold H. Subsequently, dielectric heating is performed using a high frequency of 2450 MHz in the microwave region. This expands the volume by about 200% and crosslinking hardening progresses, and the entire product becomes a gel after 10 minutes. In the above operation, the raw material before curing was heated in a high-frequency electric field by dielectric heating to promote crosslinking and curing of the stock solution before curing. However, since dielectric heating has selective heating properties, dielectric The larger the body loss coefficient, the better the microwave energy is absorbed and the faster the temperature rises. In other words, in this example, each particle of water dispersed in the form of an emulsion in the raw material before curing rises in temperature faster than the stock solution before curing, and this heat is transferred to the surrounding dispersion medium, which is the stock solution before curing. It assists dielectric heating of the stock solution, which has dielectric heating properties inferior to that of water, and promotes its crosslinking and curing. At the same time, the water itself vaporizes and expands at each occupied position, expanding the space occupied by the water in the pre-curing stock solution. At this point, the crosslinking and hardening of the stock solution has also progressed, and the crosslinking and hardening further progresses with the space expanded, forming pores 4 in the areas where water W was present, and the whole becomes porous. Fixed. In order to ensure crosslinking, it may be left for 1 to 2 hours under hot air at 80°C, for example. Furthermore, although this example uses a mold, for example, when obtaining a sheet-like product from the beginning, the raw material before hardening is poured onto a glass plate with spacers on all sides.
'' All you have to do is stack the glass plates on top of each other and irradiate them with microwaves. Furthermore, in order to carry out this process continuously, the raw material before hardening is poured out onto a belt, passed through a tunnel that is irradiated with microwaves, and if heating is required, it is irradiated with far infrared rays, etc.・Just pass it through the channel. In addition, if water is mixed and dispersed to form an emulsion and dielectric heating is performed after some time, the -F layer and the lower layer of the sheet will form due to the slight difference in specific gravity between the water and the raw solution before curing. By creating differences in the size and distribution of water particles and curing them, it is possible to vary the porous state on both sides of the sheet. Incidentally, such a sheet is convenient when, for example, it is necessary to have many holes on the side that comes into contact with the human body, and to reduce the number of holes on the side that does not come into contact with the human body for purposes such as reinforcement. In addition, in this example, water was used as a representative material that has a large dielectric loss coefficient and is easily vaporized and expanded. However, since the pores formed by water alone tend to be independent, it is necessary to add alcohol to water. It is also possible to add a hydrolyzable agent that is hydrolyzed to generate gas. Therefore, an example using sodium hydrogen carbonate as such a hydrolyzable drug will be described. Note that an aqueous solution of sodium hydrogen carbonate decomposes by releasing carbon dioxide at temperatures above 65°C. In this example, a silicone gel with a penetration degree of 25 was used, and the A component S
A solution of 5 g of sodium bicarbonate dissolved in 5 g of water, which is an easily volatile liquid, is mixed into 45 pes of each of components A and B, S8, and stirred. Then, as in the previous example, one functional substance was mixed in, and this was poured into a cylindrical mold.
Dielectric heating is performed using a high frequency of 2450 MHz in the microwave region. This expands the volume by about 500%, crosslinking and curing progresses, and after 10 minutes, the entire product becomes a gel. Incidentally, in this example, the water component dispersed in the form of an emulsion in the raw material before hardening rises in temperature faster than the undiluted solution, and this heat acts not only on the undiluted solution but also on the sodium bicarbonate aqueous solution, causing hydrolysis. This promotes the generation of carbon dioxide, which contributes to the expansion of the pores formed in the stock solution. still,
Examples of hydrolyzable agents that generate gas in the presence of water include sodium hydrogen carbonate, ammonium carbonate, urea, and the like. Moreover, foamable micro hollow spheres can also be applied as a foaming aid in the presence of water. Specific examples thereof will be described below. First, as the expandable micro hollow spheres, Expancel (registered trademark) sold by Nippon Philite Co., Ltd. is used. This material is a micro hollow sphere with an average particle size of 40μ, whose shell wall is made of a copolymer of vinylidene chloride and acrylonitrile, and which contains liquid isobutane inside.By heating it to 80'C or higher, The thermoplastic shell wall softens, and at the same time the isobutane inside expands through gasification, expanding the shell wall. In this example, 2.5 g of Expancel was mixed with yk 2-5 g c= to form a slurry, which was then mixed into 95 g of the silicone gel stock solution mixture and stirred.
Further, an appropriate functional substance is mixed into this material. Note that the mixing method, dielectric heating method, etc. are the same as in the previous embodiment. This expands the volume by approximately 200%, resulting in 10
After a few minutes, the entire mixture becomes a gel. Incidentally, in this example, the water particles dispersed in the form of an emulsion in the raw material before hardening rise in temperature faster than the stock solution, and this heat acts not only on the stock solution but also on Expancel, causing it to expand. , or rupture the shell wall,
This releases the contained gas and contributes to the expansion of the pores formed in the stock solution. In addition, the foamable micro hollow spheres are
In addition to Expancel, there are other products such as Matsumoto Microspheres manufactured and sold by Matsumoto Yushi Pharmaceutical Co., Ltd.

Next, in the heat-disappearing method, a heat-disappearing substance is mixed into a silicone gel, an appropriate functional substance is further mixed in and cured, and then this material is heated to cause the heat-disappearing substance to disappear. This is a method in which pores are formed in the area where the heat-disappearing substance was present.

In addition to the above-mentioned methods, methods for producing porous bodies containing functional substances include, for example, mixing a sublimable substance such as natutanone or dry ice into a silicone gel stock solution, and then further mixing the functional substance. It is also possible to apply a method in which the material is cured and then heat is applied to sublimate the sublimable substance. In this case, the sublimable substance may be sublimated by the heat applied when curing the silicone gel stock solution.

(Effects of the Invention) The porous body containing a functional substance according to the present invention contains a functional substance in a silicone gel formed with a large number of pores, so it not only has excellent cushioning properties and vibration damping properties. thing,
It is possible to exhibit the functions possessed by functional substances. In particular, when pores are formed continuously, the functional substances contained within the gel are released to the outside air through the pores.
It is possible to further bring out the functions of functional substances.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing step-by-step the method for manufacturing a porous material containing a functional substance using the drying shrinkage method, and Figure 2 is a step-by-step illustration showing the method for producing a porous material containing a functional material using the elution method. The explanatory diagram and FIG. 3 are explanatory diagrams showing step-by-step a method for producing a porous body containing a functional substance using a microwave heating method. 1; sheet 2; swollen granules 2a; functional substance 3, glass plate 4; pores 5; fine particles 7, expanded polystyrene pole A, sodium alginate C, calcium chloride aqueous solution H; mold P, micro tube pump SA; △ component SH; B component molecule; I-luene W; water

Claims (4)

[Claims] (1) A porous body containing a functional substance, characterized in that the functional substance is contained in a silicone gel formed with a large number of pores. (2) A claim characterized in that the functional substance is one or more substances selected from a deodorant, a fragrance, an insect repellent, an insecticide, an insect attractant, an insect repellent, and a moisture absorbent. A porous body containing the functional substance according to item 1. (3) A step of mixing particles that are more soluble, shrinkable, or heat-disappearing than silicone gel into the silicone gel stock solution before hardening, a step of mixing a functional substance, a step of curing the stock solution, and then eluting the granules with a solvent;
Or, a method for producing a porous material containing a functional substance, which comprises a step of shrinking on drying or disappearing by heating to form pores in the region where the granules were present. (4) A step of emulsifying a silicone gel stock solution before hardening by adding an easily volatile liquid that has a dielectric loss coefficient larger than that of the stock solution and that does not dissolve in the stock solution, and a step of mixing a functional substance. A porous body containing a functional substance, comprising the step of dielectrically heating the emulsified stock solution to vaporize and expand the particles of the easily volatile liquid and crosslink and harden the stock solution. manufacturing method.