JP5693974B2 - Process for producing resin composition containing ultrafine metal particles - Google Patents

Description

  The present invention relates to a method for producing a resin composition containing ultrafine metal particles, and more specifically, an ultrafine metal particle-containing resin composition capable of suppressing aggregation of ultrafine metal particles and exhibiting excellent adsorption performance. It relates to a manufacturable method.

Conventionally, fatty acid metal salts have been widely used in many fields such as electronic printing, powder metallurgy, cosmetics, paints, and resin processing. For example, magnesium salts and calcium salts of fatty acids are used in cosmetics. In the field, it is used for the purpose of improving the lubricity and adhesion to the skin, and in the resin processing field, it is used for the purpose of improving the dispersibility of the pigment.
On the other hand, silver salts of fatty acids have heretofore been used as heat-developable image recording materials for photoengraving and medical applications, but recently, as described in Patent Documents 1 and 2, the average particle diameter is 1 to 100 nm. The use as a precursor for obtaining ultrafine metal particles is disclosed.

  That is, in the following Patent Document 1, an average of silver and gold whose surfaces are protected by fatty acids by thermally decomposing organometallic compounds such as fatty acid silver and fatty acid gold salt by solid phase reaction in an inert gas atmosphere. Metal ultrafine particles having a particle size of 1 to 100 nm are synthesized. On the other hand, in Patent Document 2, a mixture of a fatty acid silver or gold salt and a resin is heat-molded at a temperature not lower than the thermal decomposition start temperature of the fatty acid metal salt and lower than the deterioration temperature of the resin, and an average particle size of 1-100 nm The ultrafine metal particles are produced in a resin molded product.

Since these metallic ultra particles exhibit unique properties different from the bulk, they are applied to inkjet materials, recording materials, catalysts, etc., materials for electronic devices such as conductive pastes, and coloring materials using plasmon absorption. Applications are being studied in various fields such as the use of In addition, resin molded products in which these ultrafine metal particles are stably dispersed have been widely studied such as conductive materials, magnetic materials, and electromagnetic wave absorbing materials.
In addition, a resin compound containing ultrafine metal particles whose surface is modified with an organic acid, produced by the method described in Patent Document 2, for example, by the present applicant is a malodorous component such as methyl mercaptan, or a volatile organic compound such as formaldehyde ( Volatile Organic Compounds (hereinafter referred to as “VOC”) have been shown to have adsorption performance, and have antibacterial properties and properties to inactivate microproteins such as allergenic substances (Patent Documents 3 and 4) .

  As described above, application of metal ultrafine particles in various fields has been studied. As a production method for obtaining such metal ultrafine particles, a vapor of metal evaporated at a high temperature in a gas phase is supplied, The gas phase method in which particles are rapidly cooled by collision with gas molecules and the liquid phase method in which a reducing agent is added to a solution containing metal ions to reduce metal ions are generally used. A resin compound containing ultrafine metal particles having a narrow particle size distribution and excellent dispersion stability can be obtained by a very simple and general method. This is a highly productive manufacturing method.

  For example, in Patent Document 5 described below, after mixing a metal-containing organic compound and a thermoplastic resin, ultrafine particles in the resin are heated by heating to a temperature not lower than the decomposition start temperature of the metal-containing organic compound and lower than the complete decomposition temperature. Further, a production method has been proposed in which ultrafine particles are surface-modified and dispersed in a resin simultaneously with the synthesis.

Japanese Patent Laid-Open No. 10-183207 JP 2006-348213 A International Publication No. 2008/29932 International Publication No. 2008/69034 International Publication No. 2005/85358

However, as described in Patent Document 5, when the mixed heating of the metal-containing organic compound and the thermoplastic resin is performed at a temperature equal to or higher than the decomposition start temperature of the metal-containing organic compound, the metal ultrafine particles generated in the resin are It has been found that the ultrafine metal particles having the adsorption performance cannot be efficiently dispersed due to aggregation, and the excellent performance of the ultrafine metal particles cannot be exhibited sufficiently.
Furthermore, when heating is performed at a temperature higher than the decomposition start temperature of the metal-containing organic compound, there is a problem that the fatty acid released by the decomposition of the metal-containing organic compound volatilizes and generates smoke.

Accordingly, an object of the present invention is to provide a method for producing a resin composition containing metal ultrafine particles in which the metal ultrafine particles are efficiently dispersed uniformly without aggregation of the metal ultrafine particles in the resin.
Another object of the present invention is to effectively exhibit excellent properties such as adsorptivity of the resin composition containing ultrafine metal particles, and to improve the manufacturing or working environment by suppressing smoke generated by decomposition. An object of the present invention is to provide a method for producing a resin composition containing ultrafine metal particles that can be produced.

According to the present invention, production of ultrafine metal particle-containing resin composition in which ultrafine metal particles having an average particle diameter of 1 to 100 nm are produced and dispersed in a thermoplastic resin by mixing and heating a fatty acid metal salt and a thermoplastic resin. In the method, the resin composition has plasmon absorption, and the mixed heating of the fatty acid metal salt and the thermoplastic resin is performed at a temperature lower than the decomposition start temperature of the fatty acid metal salt. A method of manufacturing an article is provided.
In the production method of the ultrafine metal particles-containing resin composition of the present invention, compounding the previous SL fatty acid metal salt be blended in an amount of 0.001 to 5 parts by weight per 100 parts by weight of the thermoplastic resin, and a thermoplastic resin The metal component of the fatty acid metal salt is silver, and the molar ratio of the fatty acid present in the produced resin composition and the fatty acid silver blended in the thermoplastic resin is 0.4 to 1.0, Ru suitable der.

In the method for producing a resin composition containing ultrafine metal particles of the present invention, the fatty acid metal salt and the thermoplastic resin are mixed and heated at a temperature lower than the decomposition start temperature of the fatty acid metal salt, and the fatty acid metal salt is contained in the resin composition. It is an important feature to leave a part of In this way, by partially leaving the fatty acid metal salt in the resin composition containing ultrafine metal particles, the resulting ultrafine metal particle-containing resin composition has the ultrafine metal particles such as adsorptive and microprotein inactivation effects. Excellent performance is effectively expressed.
That is, when heated above the thermal decomposition start temperature of the fatty acid metal salt, substantially the entire amount of the fatty acid metal salt blended is reduced to metal. Under such heating and mixing conditions, as described above, the ultrafine metal particles are likely to aggregate, and the detached fatty acid volatilizes outside the resin composition, resulting in fuming that is undesirable in the working environment.

  In contrast, in the production method of the present invention, a part of the fatty acid metal salt remains in the resin composition without being reduced to metal by heating and mixing at a temperature lower than the decomposition start temperature of the fatty acid metal salt. To do. Under such heating conditions, the remaining fatty acid metal salt suppresses the aggregation of the ultrafine metal particles, so that the aggregation is difficult to proceed. As a result, as described later, the ultrafine metal particles such as adsorptivity and microprotein inactivation effect It is possible to effectively exhibit the superior performance of the. When the metal component of the fatty acid metal salt is silver, the molar ratio of fatty acid / mixed fatty acid silver in the ultrafine metal particle-containing resin composition obtained by the production method of the present invention is 0.4 to 1. It is preferable to set it to 0 because the progress of particle aggregation can be suppressed.

It will be described later that the ultrafine metal particle-containing resin composition in which the fatty acid metal salt remains obtained by the production method of the present invention has superior performance as compared to the ultrafine metal particle-containing resin composition in which the fatty acid metal salt does not remain. It is clear from the results of the working examples.
That is, in the examples to be described later, a film is formed from a resin composition containing ultrafine metal particles produced under the same conditions except that the heating temperature and the residence time in the twin screw extruder are different, and the absorbance of this film is measured spectrophotometrically. It was measured with a total (manufactured by Shimadzu Corporation). It is known that ultrafine particles of silver or copper exhibit a color caused by plasmon absorption caused by free electrons undergoing vibration due to an optical magnetic field. This absorption wavelength is specific to the type of metal, and in the case of silver ultrafine particles, the absorption is in the vicinity of a wavelength of 420 nm.
1 that the film of Example 4 has absorption due to silver plasmon absorption at around 420 nm, and it can be confirmed that silver ultrafine particles are produced and dispersed in the resin. In addition, compared with the film of Comparative Example 4, the film obtained by the production method of the present invention has a higher absorbance near 420 nm, and it can be seen that the silver ultrafine particles are uniformly dispersed.
This result shows that the ultrafine silver particles having a specific particle size distribution are stably dispersed without agglomeration in the molded article composed of the resin composition containing ultrafine metal particles by the production method of the present invention. Such a molded article is also superior to the resin composition containing ultrafine metal particles obtained by heating at a temperature equal to or higher than the decomposition start temperature of the fatty acid metal salt in the adsorption performance of odorous substances such as methyl mercaptan. It is clear that it is excellent.

Moreover, in the manufacturing method in which the set temperature of the extrusion molding is performed at a processing condition of 240 ° C. which is equal to or higher than the decomposition start temperature of the fatty acid metal salt, fuming at the time of molding is remarkably observed, and the volatiles are derived from the mixed fatty acid silver (Comparative Example 2). It is obvious that this is an unsuitable production method for continuous production due to fuming during molding. On the other hand, in the production method of the present invention, no smoke was observed during molding (Examples 1 to 10), and the production / working environment was not impaired, and the resin composition was continuously and efficiently produced. It can be seen that manufacturing is possible.
From the results described above, the production method of the present invention is uniformly dispersed without aggregation of silver ultrafine particles in the composition as compared with the conventional production method, and has excellent adsorption performance for odorous substances such as methyl mercaptan, This indicates that there is no smoke during molding and that the manufacturing environment is excellent.

According to the method for producing a resin composition containing ultrafine metal particles of the present invention, an ultrafine metal particle-containing resin in which ultrafine metal particles having an average particle diameter of 1 to 100 nm are uniformly dispersed without aggregation of ultrafine metal particles in the resin. A composition can be obtained efficiently.
Further, the ultrafine metal particle-containing resin composition obtained by the production method of the present invention can effectively adsorb odor components and VOC, can exhibit excellent deodorizing performance or VOC adsorption performance, and It becomes possible to effectively inactivate pollen and mite-derived allergen substances, enzymes, or microproteins such as viruses.
Furthermore, when the metal ultrafine particle-containing resin composition is produced, smoke is not generated as in the conventional method, and the metal ultrafine particle-containing resin composition can be produced without impairing the production or working environment.

It is a graph which shows the light absorbency of the resin composition which added the silver stearate of Example 4 and Comparative Example 4.

(Fatty acid metal salt)
The type of metal in the fatty acid metal salt used in the present invention is at least one selected from the group consisting of Cu, Ag, Au, In, Pd, Pt, Fe, Ni, Co, Zn, Nb, Ru, and Rh. In particular, Cu, Ag, Co, and Ni are desirable because of their high deodorizing and antibacterial performance. Further, a plurality of metals may be included. In this case, it is desirable to use Ag as an essential component and to combine at least one other metal other than Ag.
Moreover, the fatty acid in the fatty acid metal salt used in the present invention is a fatty acid having 3 to 30 carbon atoms and may be either saturated or unsaturated. Examples of such include caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, stearic acid, arachidic acid, and behenic acid. Moreover, multiple fatty acids may be contained.

(Thermoplastic resin)
In the present invention, as the resin that can be mixed with the fatty acid metal salt, any conventionally known resin can be used as long as it is a thermoplastic resin that can be melt-molded. For example, low-, medium-, high-density polyethylene, linear Low density polyethylene, linear ultra-low density polyethylene, isotactic polypropylene, syndiotactic polypropylene, propylene-ethylene copolymer, polybutene-1, ethylene-butene-1 copolymer, propylene-butene-1 copolymer, Olefin resin such as ethylene-propylene-butene-1 copolymer, polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polyamide resin such as nylon 6, nylon 6,6, nylon 6,10, polycarbonate resin, etc. In particular Ethylene, polypropylene, the use of polyester is suitable.
In addition, the above-mentioned thermoplastic resin has various compounding agents known per se, for example, a filler, a plasticizer, a leveling agent, a thickening agent, a thickening agent, a stabilizer, an antioxidant, and an ultraviolet absorber. An agent or the like can also be contained in the resin according to a known formulation.

(Method for producing resin composition containing ultrafine metal particles)
In the present invention, a fatty acid metal salt and a thermoplastic resin are mixed and heated to produce a metal ultrafine particle-containing resin composition in which ultrafine metal particles are produced and dispersed in a thermoplastic resin. It is important that the mixed heating of the metal salt and the thermoplastic resin is performed at a temperature lower than the decomposition start temperature of the fatty acid metal salt.
In the present invention, the temperature lower than the decomposition start temperature of the fatty acid metal salt is not particularly limited as long as the fatty acid desorbed from the ultrafine metal particles and the fatty acid metal salt is present in the produced resin composition.
That is, the preparation of a resin composition containing ultrafine metal particles is generally carried out by mixing and heating a fatty acid metal salt and a thermoplastic resin as raw materials in a twin-screw extruder. In order to form fine particles, it is necessary to heat at a temperature equal to or higher than the decomposition start temperature of the fatty acid metal salt. The decomposition start temperature of the fatty acid metal salt is a temperature at which the fatty acid portion begins to desorb or decompose from the metal portion, and the start temperature is generally defined by JIS K 7120. According to this, the mass of the organic compound (fatty acid metal salt) is measured, and thermogravimetry (TG) is performed to measure the change in weight when the temperature is raised in an inert atmosphere using a thermogravimetry apparatus. The decomposition start temperature is calculated from the thermogravimetric curve (TG curve) obtained by the measurement. It is defined that the temperature at the point where the line parallel to the horizontal axis passing through the mass before the start of test heating and the tangent line at which the gradient between the bending points in the TG curve becomes maximum is the starting temperature. However, the present invention does not require heating at a temperature higher than the decomposition start temperature of the fatty acid metal salt defined above. This is because, in practice, in the present invention, while being heated at a temperature lower than the decomposition start temperature of the fatty acid metal salt, it is affected by the shear heat generation by the screw or the residence time in addition to the set temperature of the twin screw extruder. The fatty acid metal salt is decomposed to form ultrafine metal particles by adjusting processing conditions such as residence time, heating time, and screw rotation speed.

  The processing conditions of the fatty acid metal salt cannot be generally limited. For example, when stearic acid having a decomposition start temperature of 220 ° C. as a fatty acid is used as a fatty acid according to JIS definition, 140 ° C. to 220 ° C. It is preferable to perform heating and mixing at a temperature of less than 5 ° C., depending on the setting temperature of the twin screw extruder at a temperature within this range, with a heating time of 5 to 1800 seconds, particularly 10 to 300 seconds.

In the production method of the present invention, it is preferable to blend the fatty acid metal salt in an amount of 0.001 to 5 parts by weight per 100 parts by weight of the thermoplastic resin. On the other hand, if the amount is larger than the above range, the ultrafine metal particles are aggregated and uniform dispersion may be difficult, which is not preferable.
In the present invention, as described above, from a molten resin obtained by mixing and heating a thermoplastic resin and a fatty acid metal salt at a temperature lower than the decomposition start temperature of the fatty acid metal salt, a two-roll method, injection molding, extrusion molding, compression molding, etc. Through a conventionally known melt molding, a resin molded body such as a shape, for example, a granular shape, a pellet shape, a fiber shape, a film, a sheet, or a container can be formed according to the use of the final molded product.
Moreover, although the resin composition containing a fatty acid metal salt obtained by the present invention can be used alone to form a resin molded article containing ultrafine metal particles, it can also have a multilayer structure in combination with other resins.

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples.
(Production of fatty acid silver)
Liquid A was prepared by dissolving 76.6 g of sodium stearate in 3000 g of water at 90 ° C., and liquid B was prepared by dissolving 40.3 g of silver nitrate in 600 g of water. Next, the B liquid was thrown into the A liquid while stirring the A liquid. The mixture was stirred for 15 minutes and thoroughly washed with deionized water while performing solid-liquid separation by suction filtration. The obtained silver stearate was dried with a hot air dryer (manufactured by Tabai Espec).

(Calculation of decomposition temperature of fatty acid silver)
In accordance with JIS K7120, the mass of silver stearate was measured, and the weight loss from 30 to 600 ° C. was measured at a temperature increase rate of 10 ° C./min in a nitrogen atmosphere using a thermogravimetric apparatus (manufactured by PerkinElmer). From the TG curve obtained by measurement, calculate the temperature at the point where the line parallel to the horizontal axis (temperature) passing through the mass before the start of test heating and the tangent line where the gradient between the bending points is maximum intersect, and stearic acid It was set as the decomposition start temperature of silver.

(Confirmation of plasmon absorption)
The resin composition obtained by mixing and heating the fatty acid silver and the thermoplastic resin was measured with a spectrophotometer (UV-3100PC, manufactured by Shimadzu Corporation) to determine the absorbance. In addition, it is known that ultrafine particles such as silver and copper show a color caused by plasmon absorption caused by vibration of a free electron by an optical magnetic field. This absorption wavelength is specific to the type of metal. When the ultrafine silver particles are contained in the resin, plasmon absorption is observed near the wavelength of 420 nm.

(Confirmation of smoke and analysis of volatiles)
Smoke during molding of the resin composition was visually confirmed, and the generated smoke was collected to obtain volatiles. Volatiles were methyl esterified, extracted with hexane, and analyzed by GC-MS. The component ratio was calculated from the area ratio of each peak with different retention times obtained by analysis, and the main component was identified.

(Measurement of methyl mercaptan before deodorization)
5 μl of malodorous methyl mercaptan was injected with a microsyringe into a 500 ml glass bottle replaced with nitrogen gas whose mouth was sealed with a rubber stopper, and left at room temperature (25 ° C.) for 1 day. After leaving for one day, a gas-tech detector tube was inserted into the bottle, and the amount of residual methyl mercaptan was measured to obtain the amount of methyl mercaptan (A) before deodorization.

(Measurement of methyl mercaptan after deodorization)
The films prepared according to Examples 1 to 10 and Comparative Examples 1 to 6 were cut into 5 cm squares (weight 0.1 g), placed in a 500 ml glass bottle substituted with nitrogen gas, and sealed with a rubber stopper. The malodorous methyl mercaptan (5 μl) was injected into the tube with a microsyringe and left at room temperature (25 ° C.) for 1 day. After leaving for 1 day, a GASTEC detector tube was inserted into the bottle, the amount of residual methyl mercaptan was measured, and the amount of methyl mercaptan (B) after deodorization was determined.

(Calculation of methyl mercaptan deodorization rate)
The value obtained by subtracting the methyl mercaptan amount (B) after deodorization from the methyl mercaptan amount (A) before deodorization was divided by the methyl mercaptan amount (A) before deodorization and defined as a percentage.

Example 1
Silver stearate prepared by the above-described method and calculated for decomposition start temperature is blended in 3 kg of low density polyethylene resin so as to have a content of 0.5 wt%, and the extruder setting temperature is 160 ° C., Q (discharge amount) ) / N (screw rotation speed) = 3/150 = 0.02 Extruded with a twin screw extruder (manufactured by Toyo Seiki Seisakusho) to produce a film with a thickness of 50 μm. Confirmation, confirmation of smoke generation, analysis of volatile substances, measurement of the amount of methyl mercaptan, and calculation of the amount of deodorization of methyl mercaptan were performed. The results are shown in Table 1.

(Example 2)
A film was prepared in the same manner as in Example 1 except that the extruder set temperature was 180 ° C., confirmation of plasmon absorption, confirmation of fuming and analysis of volatiles, measurement of methyl mercaptan amount, deodorization amount of methyl mercaptan Was calculated. The results are shown in Table 1.

(Example 3)
A film was prepared in the same manner as in Example 1 except that the extruder set temperature was 190 ° C., confirmation of plasmon absorption, confirmation of smoke generation, analysis of volatiles, measurement of methyl mercaptan amount, deodorization amount of methyl mercaptan Was calculated. The results are shown in Table 1.

Example 4
A film was produced in the same manner as in Example 1 except that the temperature set for the extruder was 200 ° C., confirmation of plasmon absorption, confirmation of smoke generation, analysis of volatiles, measurement of the amount of methyl mercaptan, amount of deodorization of methyl mercaptan Was calculated. The results are shown in Table 1.

(Example 5)
A film was prepared in the same manner as in Example 1 except that the extruder set temperature was 210 ° C., confirmation of plasmon absorption, confirmation of smoke generation, analysis of volatiles, measurement of methyl mercaptan amount, deodorization amount of methyl mercaptan Was calculated. The results are shown in Table 1.

(Example 6)
A film was produced in the same manner as in Example 1 except that the resin was changed to polyolefin and the extruder was set at 180 ° C. and Q (discharge amount) / N (screw rotation speed) = 3/100 = 0.03. Then, confirmation of plasmon absorption, confirmation of smoke generation, analysis of volatiles, measurement of the amount of methyl mercaptan, and calculation of the deodorizing amount of methyl mercaptan were performed. The results are shown in Table 1.

(Example 7)
Example 1 except that the silver stearate was 0.2 wt%, the extruder setting temperature was 180 ° C., and Q (discharge amount) / N (screw rotation speed) = 3/50 = 0.06. A film was prepared, plasmon absorption was confirmed, smoke was confirmed and volatiles were analyzed, the amount of methyl mercaptan was measured, and the deodorization amount of methyl mercaptan was calculated. The results are shown in Table 1.

(Example 8)
Example 1 except that the silver stearate was 1.5 wt%, the extruder setting temperature was 180 ° C., and Q (discharge amount) / N (screw rotation speed) = 3/100 = 0.03. A film was prepared, plasmon absorption was confirmed, smoke was confirmed and volatiles were analyzed, the amount of methyl mercaptan was measured, and the deodorization amount of methyl mercaptan was calculated. The results are shown in Table 1.

Example 9
A film was prepared in the same manner as in Example 1 except that silver myristate was changed to 0.5 wt% and the extruder was set at 180 ° C., confirmation of plasmon absorption, confirmation of fuming and analysis of volatiles, methyl mercaptan The amount was measured and the amount of deodorization of methyl mercaptan was calculated. The results are shown in Table 1.

(Example 10)
A film was prepared in the same manner as in Example 1 except that silver behenate was changed to 0.5 wt% and the extruder set temperature was 180 ° C., confirmation of plasmon absorption, confirmation of fuming, analysis of volatiles, methyl mercaptan The amount was measured and the amount of deodorization of methyl mercaptan was calculated. The results are shown in Table 1.

(Comparative Example 1)
A film was prepared in the same manner as in Example 1 except that the extruder set temperature was set to 130 ° C., confirmation of plasmon absorption, confirmation of smoke generation, analysis of volatiles, measurement of methyl mercaptan amount, deodorization amount of methyl mercaptan Was calculated. The results are shown in Table 1.

(Comparative Example 2)
A film was produced in the same manner as in Example 1 except that the temperature set at the extruder was 240 ° C., confirmation of plasmon absorption, confirmation of fuming and analysis of volatiles, measurement of the amount of methyl mercaptan, amount of deodorization of methyl mercaptan Was calculated. The results are shown in Table 1.

(Comparative Example 3)
A film was produced in the same manner as in Example 1 except that the extruder set temperature was set to 260 ° C., confirmation of plasmon absorption, confirmation of smoke generation, analysis of volatiles, measurement of methyl mercaptan amount, deodorization amount of methyl mercaptan Was calculated. The results are shown in Table 1.

(Comparative Example 4)
A film was produced in the same manner as in Example 1 except that the extruder set temperature was 280 ° C., confirmation of plasmon absorption, confirmation of smoke generation and analysis of volatiles, measurement of methyl mercaptan amount, deodorization amount of methyl mercaptan Was calculated. The results are shown in Table 1.

(Comparative Example 5)
A film was prepared in the same manner as in Example 1 except that silver myristate was changed to 0.5 wt% and the extruder set temperature was set to 260 ° C., confirmation of plasmon absorption, confirmation of fuming and analysis of volatiles, methyl mercaptan The amount was measured and the amount of deodorization of methyl mercaptan was calculated. The results are shown in Table 1.

(Comparative Example 6)
A film was prepared in the same manner as in Example 1 except that silver behenate was changed to 0.5 wt% and the extruder set temperature was set to 260 ° C., confirmation of plasmon absorption, confirmation of fuming, analysis of volatiles, methyl mercaptan The amount was measured and the amount of deodorization of methyl mercaptan was calculated. The results are shown in Table 1.

  The method for producing a resin composition containing ultrafine metal particles according to the present invention is capable of producing an ultrafine metal particle-containing resin composition in which ultrafine metal particles are efficiently dispersed without aggregation of ultrafine metal particles in the resin. In addition, there is no smoke during production, and the production environment is excellent. Therefore, the ultrafine metal particle-containing resin composition having excellent properties such as adsorptivity can be efficiently produced in various forms such as granular, pellet-like, fibrous, film, sheet, and container. It can be used in the industrial field.

Claims (3)

In the method of producing a resin composition containing ultrafine metal particles, in which ultrafine metal particles having an average particle diameter of 1 to 100 nm are produced and dispersed in a thermoplastic resin by mixing and heating a fatty acid metal salt and a thermoplastic resin, the resin composition The product has a plasmon absorption, and the mixed heating of the fatty acid metal salt and the thermoplastic resin is performed at a temperature lower than the decomposition start temperature of the fatty acid metal salt.   The method for producing a resin composition containing ultrafine metal particles according to claim 1, wherein the fatty acid metal salt is blended in an amount of 0.001 to 5 parts by weight per 100 parts by weight of the thermoplastic resin. The metal component of the fatty acid metal salt blended in the thermoplastic resin is silver, and the molar ratio of the fatty acid present in the produced resin composition and the fatty acid silver blended in the thermoplastic resin is 0.4 to 1. The method for producing a resin composition containing ultrafine metal particles according to claim 1 or 2, wherein the composition is zero.

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