Method for molding synthetic resin molding having light-shielding property, heat-dissipation property and conductivity

Abstract

To provide a method for molding a synthetic resin molding having light-shielding property, to provide a method for molding a synthetic resin molding having light-shielding property as synthetic resin moldings having various shapes using synthetic resin pellets composed of various materials, according to a conventional method for molding a synthetic resin molding, and to impart properties other than the light-shielding property to a synthetic resin molding.SOLUTION: A mass 2 of aggregates of carbon black is dispersed in alcohol having two properties of a boiling point lower than a temperature at which molding of a synthetic resin is started, and viscosity at 20°C of 2-3 mPa / sec, and a suspension in which the mass of the aggregates is dispersed in the alcohol is prepared. Subsequently, the whole surface of a synthetic resin pellet 1 is evenly covered with the suspension. Furthermore, a synthetic resin molding having light-shielding property, heat-dissipation property and conductivity is molded using the mass of the synthetic resin pellets covered with the suspension according to a conventional method for molding a synthetic resin molding.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] In this invention, first, a suspension is prepared by dispersing clusters of carbon black aggregates in alcohol with a boiling point lower than the temperature at which the synthetic resin begins to mold and a viscosity of 2-3 mPa·sec at 20°C. Next, the entire surface of synthetic resin pellets is evenly covered with the suspension. Furthermore, the clusters of synthetic resin pellets covered with the suspension are used to mold a synthetic resin body that combines light-blocking, heat-dissipating, and conductive properties according to conventional synthetic resin molding methods. Furthermore, when the entire surface of a synthetic resin pellet is evenly covered with a cluster of carbon black aggregates and the cluster of pellets is used to mold a molded body using conventional synthetic resin molding methods, the molded body has excellent light-blocking properties due to the carbon black's low total light transmittance of 0%. Therefore, even if the molded body is continuously irradiated with ultraviolet light, it will not deteriorate. Furthermore, carbon black has a high thermal emissivity, which is the ratio of the thermal emissivity of a black body, of 0.95-0.97. Therefore, the molded body has excellent heat dissipation properties. Furthermore, the resistivity of carbon black is six orders of magnitude higher than that of metals but 13 orders of magnitude lower than that of synthetic resins. Therefore, due to the conductivity of carbon black, the molded body combines the functions of conductivity, electromagnetic wave shielding, and antistatic properties. Furthermore, because the aggregates made up of clusters of carbon particles have excellent corrosion resistance, the molded body has excellent corrosion resistance.

[0002] Meanwhile, the inventor has filed patent application No. 2021-041845 for an invention to create conductive yarn, fabric, and nonwoven fabric using carbon black. This prior application creates a collection of aggregates in which the aggregates are entangled with each other via 1-heptanol, which has a vapor pressure of 15 Pa at 20°C, a viscosity of 5.2 mPa·sec at 20°C, and a surface tension of 26 dyn / cm at 20°C; places the yarn, fabric, or nonwoven fabric in the chamber of a vacuum impregnation device; reduces the pressure inside the chamber to a pressure lower than the vapor pressure of the 1-heptanol, evacuates the air occupying the voids in the yarn, fabric, or nonwoven fabric; fills the reduced-pressure chamber with the collection of aggregates; impregnates the voids previously occupied by the yarn, fabric, or nonwoven fabric with the collection of aggregates; and adsorbs the collection of aggregates onto the surface of the yarn, fabric, or nonwoven fabric. In contrast, the present invention uses a liquid alcohol that has both the first property of having a viscosity of 2-3 mPa·sec at 20°C and the second property of having a boiling point lower than the temperature at which synthetic resin molding begins to occur to create aggregate clusters in which the aggregates are entangled with each other. The entire surface of a synthetic resin pellet is then evenly covered with the aggregate clusters of carbon black aggregates, and the pellets are then molded into a molded body using a conventional synthetic resin molding method. [Background technology]

[0003] The prior art closest to the present invention is a technique for imparting light-blocking properties to synthetic resins. For example, Patent Document 1 is a patent that provides light-blocking properties to a synthetic resin container by covering the outside of the container with a foam consisting of many bubbles. However, there is no description at all as to why a foam consisting of many bubbles provides light-blocking properties. Patent Document 2 describes molding a synthetic resin container by extrusion blow molding and providing a light-shielding layer on the inner surface of the container body, but does not specifically describe the light-shielding layer, and therefore does not describe at all why the light-shielding layer provides light-shielding properties. On the other hand, it is known that the molecular structure of polymeric materials, not limited to synthetic resins, is destroyed by ultraviolet rays, causing the polymeric materials to deteriorate. However, Patent Document 1 does not mention the relationship between the light-blocking properties and foams, and Patent Document 2 does not mention the light-blocking properties and the configuration of the light-blocking layer. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2022-119649 [Patent Document 2] Japanese Patent Publication No. 2020-183281 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0005] The problems that the present invention aims to solve are, first, to find a method for molding a synthetic resin molded article with light-blocking properties. Second, to find a method for molding synthetic resin molded articles made of various materials and shapes using conventional synthetic resin molding methods into a molded article with light-blocking properties. Third, to be able to impart added value other than light-blocking properties to synthetic resin molded articles. These three problems are the problems that the present invention aims to solve. [Means for solving the problem]

[0006] Carbon black aggregates are dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets The method for producing the evenly coated pellets of the synthetic resin is as follows: A predetermined weight of a liquid alcohol having a first property of having a viscosity of 2-3 mPa·sec at 20°C and a second property of having a boiling point lower than the temperature at which synthetic resin begins to be molded is added to the predetermined weight of the liquid alcohol. Consists ofThe carbon black aggregates are placed in a container, and the alcohol is stirred to prepare a first suspension in which the carbon black aggregates are immersed in the alcohol. Thereafter, a plate material covering the entire surface of the first suspension is placed on the first suspension. Furthermore, a compressive load is applied evenly to the entire surface of the plate material. etc. and crushing the carbon black clusters immersed in the alcohol; further, the plate is lifted out of the first suspension, the container is placed on a vibration table of a vibrator, the vibrator is operated, and acceleration in three directions, i.e., forward and backward, left and right, and up and down, is repeatedly applied to the container to rearrange the crushed carbon black clusters in the alcohol; thereafter, the plate is covered with the first suspension again, and the compressive load is applied again evenly to the entire surface of the plate to further crush the carbon black clusters immersed in the alcohol; further, the plate is lifted out of the first suspension again, and the acceleration in the three directions is repeatedly applied to the container; and these paired processes consisting of the process of applying the compressive load and the process of applying the acceleration are repeated on the container, and when the compressive load is applied to the plate, When the pulverization of the carbon black by compression of the plate material reaches its limit, even if the pulverized carbon black is compressed, the carbon black is not pulverized and a repulsive force is generated in the plate material. a first step of determining that the crushing of the carbon black mass immersed in the alcohol is completed when a repulsive force is generated in the plate material, and stopping the pair of processes, and then removing the plate material from the container; An ultrasonic homogenizer is placed in the container, and the homogenizer is operated to repeatedly apply shock waves to the aggregates of the pulverized carbon black via the alcohol, thereby separating the entanglements of aggregates in the pulverized carbon black, allowing the alcohol to be adsorbed by the separated sites, and The aforementioned The aggregates are entangled with each other through the alcohol. The aforementioned a second step of preparing a second suspension comprising a collection of entangled aggregates; A collection of synthetic resin pellets having a weight less than the weight of the second suspension in the container is introduced into the container, the collection of synthetic resin pellets is stirred, and the collection of synthetic resin pellets is mixed with the second suspension. Mediuma third step of immersing the synthetic resin pellets in the second suspension, and then removing the collection of synthetic resin pellets from the container, thereby causing the second suspension to be adsorbed onto the entire surfaces of the synthetic resin pellets to a thickness depending on the viscosity of the second suspension, thereby creating a collection of synthetic resin pellets whose entire surfaces are evenly covered with the second suspension; The above three steps All processing in The method of continuously performing the above is as follows: mosquito -The aggregates of Bomb Black are dispersed in alcohol to form a suspension. The entire surface of the synthetic resin pellets A method for producing a collection of pellets of the synthetic resin that are uniformly coated.

[0007] In other words, in the following three very simple steps All By carrying out the treatment in succession, the entire surface of the synthetic resin pellets can be evenly covered with a suspension of carbon black aggregates dispersed in alcohol. Here, we will explain the treatment in three steps and the effects of the treatment. The first step is to prepare a suspension of crushed carbon black particles in alcohol, which has two properties. Applicable Weight greater than the weight of the carbon black aggregate Consists ofAlcohol is poured into a container and stirred to create a first suspension in which carbon black clumps are immersed in alcohol. In other words, by compressing the carbon black clumps immersed in alcohol, the carbon black clumps can be easily pulverized. A plate that covers the entire surface of the first suspension is then placed over the first suspension, and a compressive load is applied evenly to the entire surface of the plate, pulverizing the carbon black clumps immersed in alcohol. The plate is then lifted from the first suspension, and the container is placed on a vibration table of a vibrator. The vibrator is operated to repeatedly apply acceleration to the container in three directions: forward / backward, left / right, and up / down. This causes the pulverized carbon black clumps to be rearranged in the alcohol. In other words, there is variation in the size of the carbon black particles in the carbon black clumps, and the size of the crushed carbon black also varies. Therefore, voids are formed in the crushed carbon black clumps. To fill these voids, the crushed carbon black clumps are rearranged in alcohol and crushed again, thereby advancing the crushing of all the carbon black and making the crushed carbon black particles closer to uniform in size. The plate is then covered with the first suspension again, and the compressive load is applied evenly to the entire surface of the plate again, further pulverizing the carbon black clumps in the alcohol. The plate is then lifted out of the first suspension, and the three-directional acceleration is applied to the container again. This pair of processes consisting of applying a compressive load and applying an acceleration is repeated. When a repulsive force is generated in the plate when the compressive load is applied to the plate, it is determined that the pulverization of the carbon black clumps immersed in the alcohol is complete, and the pair of processes is stopped. The plate is then removed from the container. In other words, when the pulverization of the carbon black by compressing the plate reaches its limit, even if the pulverized carbon black is compressed or a compressive stress is applied to the finely divided carbon black, the carbon black is not pulverized, and a repulsive force is generated in the plate. At this point, it is determined that the pulverization of the carbon black clumps is complete. As a result, the carbon black is pulverized to a size approximately 1 / 25 of its original size. The smallest unit of carbon black is the aggregate, which is a primary agglomeration of carbon particles. In carbon black, this aggregate is a collection of carbon particles, each 10-100 nm in size, bound together in an irregular, complex, string-like structure (called a "structure"). Aggregates range in size from 100-500 nm and contain 100-1000 carbon particles. Therefore, aggregates are extremely lightweight and can be cut. These aggregates easily become entangled by the structure, forming agglomerates, which are secondary agglomerations of carbon particles and aggregate clusters. Therefore, by crushing carbon black, the agglomerates are also crushed, and the size of the agglomerates is reduced to approximately 1 / 25 of their original size. The aggregates are also cut into lengths of 0.2 mm or less. When the alcohol evaporates in the third step, the aggregates are cut, and the cut aggregates randomly overlap and precipitate on the surface of the synthetic resin pellets, evenly covering the entire surface of the synthetic resin pellets. When pellets whose surfaces are evenly covered with such aggregates are thermally deformed and the thermally deformed pellets are bonded together, the synthetic resin molded body has the properties of the aggregates. Therefore, in the present invention, the entire surface of the synthetic resin pellets is evenly covered with a suspension in which carbon black aggregates are dispersed in alcohol. The second step is to separate the entanglements of the crushed aggregates. In other words, in the third step, in order for the crushed aggregates to randomly overlap and evenly cover the entire surface of the synthetic resin pellets, it is necessary to separate the entanglements between the crushed aggregates. Note that the entanglement between the aggregates is simply a matter of the aggregates contacting each other, and the bonding strength between the entangled aggregates is weak. On the other hand, carbon black is largely composed of agglomerates, which are aggregate aggregates that have aggregated together, and the largest aggregates can be as large as nearly 1 mm. For this reason, it is difficult to prepare a suspension in which the agglomerate aggregates are dispersed in alcohol, and it is even more difficult to cover the pellets with the agglomerate aggregates. For this reason, a homogenizer is operated in alcohol, shock waves are continuously applied to the pulverized agglomerates, and the portions where the aggregates are directly entangled are separated by the irradiation of the shock waves, and alcohol is adsorbed onto the separated portions, causing the aggregates to entangle with each other via the alcohol. This makes it possible to prepare a suspension in which aggregates of carbon black are dispersed in alcohol, and the suspension Medium By simply immersing a collection of synthetic resin pellets in the suspension, it is possible to evenly cover the entire surface of the synthetic resin pellets. Furthermore, because the carbon black was crushed to its physically limited size, the aggregates were cut into lengths of 0.2 mm or less. Therefore, by continuously applying shock waves, the entanglements between the aggregates can be easily released. This allows the collection of crushed aggregates entangled via the alcohol to be evenly dispersed in the low-viscosity alcohol, forming a second suspension. That is, when a homogenizer is placed in a container and operated in alcohol, fine shock waves are generated in the alcohol, and the shock waves move through the alcohol while exciting the alcohol molecules. On the other hand, because the viscosity of alcohol is low, little energy is consumed when the alcohol molecules are excited by the shock waves, and the energy of the shock waves is not easily lost. Therefore, fine shock waves are efficiently and repeatedly irradiated onto the pulverized agglomerate clusters through the alcohol. As a result, fine shock waves are repeatedly irradiated onto the areas where the aggregates are directly entangled with each other, and because the aggregates are extremely lightweight, the directly entangled areas are released, and the alcohol is adsorbed onto the areas of the disentangled aggregates. As a result, the pulverized agglomerate clusters immersed in alcohol become a second suspension in which the entangled aggregate clusters are evenly dispersed in the alcohol. Furthermore, the aggregates have an irregular, complex structure in which carbon particles are strung together, and the length and shape of each aggregate vary. Therefore, even if the shock waves emitted by the homogenizer are repeatedly applied to the agglomerates, even if the aggregates are fragmented, all of the areas where the aggregates are directly entangled are separated. This separates the aggregates into individual aggregates, and the separated aggregates cannot be evenly dispersed in alcohol. In other words, the separation of aggregate entanglements using the homogenizer is merely a process of adsorbing alcohol onto the areas where the aggregates are directly entangled. This process allows the aggregates, in which the aggregates are entangled via alcohol, to be evenly dispersed in alcohol. Therefore, in the aggregates in which the aggregates are entangled with each other via the alcohol, the entangled aggregates are not directly bonded to each other, but are uniformly dispersed in the alcohol. As a result, when the alcohol is evaporated in the third step, the cut aggregates overlap randomly and precipitate on the surface of the synthetic resin pellet, so that the aggregates can cover the entire surface of the pellet evenly. When an ultrasonic homogenizer is used as the homogenizer, a huge number of bubbles that are significantly smaller than the size of the crushed aggregates are simultaneously generated, and then the bubbles disappear almost simultaneously. This generation and disappearance of bubbles occurs repeatedly according to the ultrasonic generation cycle, and the generation and disappearance of bubbles is repeated in the low-viscosity alcohol (this phenomenon is called cavitation). Shock waves generated when the bubbles burst are continuously generated in the low-viscosity alcohol, and the energy of the shock waves is hardly absorbed by the alcohol and is continuously irradiated to the fine parts of the agglomerates, causing the parts where the aggregates are directly entangled to separate in a short period of time, and the alcohol is adsorbed to the separated parts. Therefore, the ultrasonic homogenizer repeatedly generates and disappears bubbles according to the ultrasonic generation cycle, and separates the parts where the aggregates are directly entangled in a relatively short period of time. The third step is to adsorb the second suspension onto the entire surface of the synthetic resin pellets, thoroughly covering the entire surface of the synthetic resin pellets with the second suspension. To achieve this, a collection of synthetic resin pellets, weighing less than the weight of the second suspension, is placed in a container and stirred. This causes the collection of synthetic resin pellets to be immersed in the second suspension. The collection of synthetic resin pellets is then removed from the container. This causes the second suspension to adsorb onto the entire surface of the synthetic resin pellets to a thickness depending on the viscosity of the second suspension. As a result, the entire surface of the synthetic resin pellets is thoroughly covered with the second suspension. Because the viscosity of alcohol is low, at 2-3 mPa·sec at 20°C, the thickness of the second suspension adsorbed onto the surface of the synthetic resin pellets is thin, at less than 3 μm. Meanwhile, because the agglomerates are crushed to a size of approximately 1 / 25, the size of the crushed aggregates is significantly finer than the initial 100-500 nm. Therefore, even if the thickness of the adsorbed second suspension is 3 μm or less, the aggregates overlap randomly via the alcohol, and cover the entire surface of the synthetic resin pellets evenly.

[0008] As stated in paragraph 6 mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets The method for producing the evenly coated pellets of the synthetic resin is as follows: The alcohol mentioned in paragraph 6 、 Related to boiling point Next Three nature have It is an alcoholic beverage. , first Boiling Point Properties The synthetic resins mentioned in paragraph 6 As pellets of thermosetting resin The boiling point of pellets is can be, The first The boiling point is The aforementioned Lower than the temperature at which the polymerization reaction of thermosetting resin occurs Also, Second Boiling Point Properties The synthetic resins mentioned in paragraph 6 As pellets Amorphous thermoplastic resin Use pellets of case Boiling point properties of and The secondThe boiling point is lower than the glass transition point of the amorphous thermoplastic resin. moreover, Third Boiling Point Properties The synthetic resins mentioned in paragraph 6 As pellets of crystalline thermoplastic resin Use pellets of case Boiling point properties of and The third The boiling point of The aforementioned These boiling points are lower than the melting points of crystalline thermoplastic resins. The aforementioned Three nature Alcohol with the following characteristics is listed in paragraph 6: Use according to the material of the synthetic resin pellets , the three steps described in paragraph 6 All processing in By continuously carrying out the steps above, the entire surface of the synthetic resin pellet is evenly covered with a suspension of aggregates of carbon black dispersed in alcohol. mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets A method for producing a collection of pellets of the synthetic resin that are uniformly coated.

[0009] In other words, synthetic resins are broadly divided into thermoplastic resins and thermosetting resins. Thermosetting resins undergo a polymerization reaction when heated, forming a polymer network structure that hardens and does not return to its original state. For this reason, thermosetting resins do not have a melting point, and the polymerization reaction caused by heating is an irreversible change. Therefore, the temperature at which thermosetting resins begin to mold is the temperature at which the polymerization reaction of the thermosetting resin occurs. For this reason, In the present invention, when thermosetting resin pellets are used as the synthetic resin pellets, the pellets are covered with a suspension, and a collection of the pellets covered with the suspension is loaded into a molding machine or a mold. The pellets are heated by the molding machine or the mold to a temperature at which a polymerization reaction of the thermosetting resin occurs, and the pellets are heated for a predetermined time until the polymerization reaction is completed. At the time the polymerization reaction is completed, stress is applied to the pellets in which the polymerization reaction has completed by the molding machine or the mold. In contrast, when thermoplastic resins are heated, they soften and become rubber-like elastic, and if they are further heated, they lose their elasticity and become fluid (liquid phase). At this time, amorphous resins and crystalline resins behave very differently when heated. Note that crystalline resins contain a small amount of amorphous material, and amorphous resins are not entirely amorphous, with only a small portion being crystalline. In other words, when amorphous resins are heated, they transition from a glassy, ​​brittle state in which amorphous polymer chains are bonded to a state exhibiting rubber-like elasticity. This transition is called the glass transition, and the temperature at which the glass transition occurs is called the glass transition point. Further heating causes the resin to gradually transition from a rubbery, fluid state to a liquid-like, fluid state in which it loses elasticity. However, because the degree of crystallinity is extremely low, the temperature at which the entire transition is complete is unclear, and amorphous synthetic resins do not have a melting point. Therefore, the temperature at which amorphous thermoplastic resins begin to mold is the glass transition point. For this reason, In the present invention, when pellets of a non-crystalline thermoplastic resin are used as the synthetic resin pellets, the pellets are covered with a suspension, and a collection of pellets covered with the suspension is filled into a molding machine or a mold. The pellets are heated to the glass transition point of the non-crystalline thermoplastic resin using the molding machine or the mold, and heating is continued for a predetermined time until all the pellets lose their elasticity and become fluid (liquid phase), and stress is applied to the pellets in the liquid phase using the molding machine or the mold. In contrast, crystalline resins have a high degree of crystallinity, and there is a clear temperature at which the transition from a rubbery fluid state to a liquid fluid state that loses elasticity is completed. This temperature is called the melting point. Further heating reaches a temperature at which the polymer chains break. Further heating increases the number of breaks, gradually converting the polymer to a lower molecular weight. The temperature at which changes in the polymer structure begin to appear is called the thermal decomposition temperature. Once thermal decomposition begins, the polymer structure does not return to its original state. Therefore, if the temperature is not elevated above the thermal decomposition temperature, a thermally molten crystalline resin will return to its original properties upon cooling. Therefore, the melting point is the temperature at which molding of a crystalline thermoplastic resin begins. In the present invention, when pellets of a crystalline thermoplastic resin are used as synthetic resin pellets, the pellets are covered with a suspension, and the collection of pellets covered with the suspension is filled into a molding machine or mold. The pellets are heated to their melting point using the molding machine or mold, and further heated for a predetermined time until all the pellets are thermally melted. After this, stress is applied to the pellets in the liquid phase using the molding machine or mold.

[0010] As stated in paragraph 6 mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets The method for producing the evenly coated pellets of the synthetic resin is as follows: Liquid alcohols that have both of the properties described in paragraph 6 include 2-propanol, 1-propanol, and 1-butanol. 、 Or 、 Any one of the alcohols consisting of 1-pentanol, and the any one of the alcohols is used as a liquid alcohol having both of the properties described in paragraph 6, and the three steps described in paragraph 6 are carried out. All processing in By continuously carrying out the steps above, the entire surface of the synthetic resin pellet is evenly covered with a suspension of aggregates of carbon black dispersed in alcohol. mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. 、 A method for producing a collection of synthetic resin pellets in which the entire surfaces of the synthetic resin pellets are evenly covered.

[0011] In other words, liquid alcohols that possess both of the properties described in paragraph 6 include 2-propanol, 1-propanol, 1-butanol, and 1-pentanol. 2-Propanol (CH3)2CH(OH) has a viscosity of 1.8 mPa·s at 20°C and a boiling point of 82°C. 1-propanol CH3(CH2)2OH has a viscosity of 1.9 mPa·s at 20°C and a boiling point of 98°C. 1-butanol CH3(CH2)3OH has a viscosity of 3.0 mPa·s at 20°C and a boiling point of 117°C. 1-Pentanol CH3(CH2)4OH has a viscosity of 3.3 mPa·s at 20°C and a boiling point of 138°C. These four types of alcohols are liquid alcohols that have both the first property of having a viscosity of 2-3 mPa·sec at 20°C as described in paragraph 6 and the second property of having a boiling point lower than the temperature at which the synthetic resin begins to be molded. Furthermore, all of them are general-purpose alcohols. Therefore, by using any one type of alcohol as a liquid alcohol that has both the two properties as described in paragraph 6, and following the method of preparing a collection of synthetic resin pellets as described in paragraph 6, the entire surface of which is evenly covered with a suspension of carbon black aggregates dispersed in alcohol, the process is carried out in three steps. All By carrying out the treatment continuously, the entire surface of the synthetic resin pellets is evenly covered with the suspension. The boiling point of alcohol is 82-138°C, which is lower than the temperature at which most synthetic resins begin to mold. This will be explained in the first embodiment.

[0012] As stated in paragraph 6 mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets The method for producing the evenly coated pellets of the synthetic resin is as follows: The carbon black described in paragraph 6 is Ketjen black, and the Ketjen black is used as the carbon black described in paragraph 6, and the three steps described in paragraph 6 are carried out. All processing in the steps of: a) to agglomerate a synthetic resin pellets whose entire surfaces are evenly covered with a suspension of aggregates of Ketjen black dispersed in alcohol; b) to agglomerate a synthetic resin pellets whose entire surfaces are evenly covered with a suspension of aggregates of carbon black dispersed in alcohol;

[0013] In other words, the characteristics of carbon black vary greatly depending on the manufacturing method, and carbon black is classified by the name of the manufacturing method. The properties of carbon black vary depending on this manufacturing method. Furnace black is carbon black produced by the incomplete combustion of oil or gas in high-temperature gas, and is subdivided into oil furnaces and gas furnaces depending on the raw material being burned. Among furnace blacks, Ketjenblack uses hydrocarbon oil as the raw material, and produces carbon black through the incomplete combustion of the oil. Among carbon blacks, Ketjenblack has the largest specific surface area and DPB (dibutyl phthalate) absorption, and its conductivity is second only to acetylene black. In other words, Ketjenblack has a hollow structure formed by an arc, and electrons move through the arc-shaped structure, increasing the conductivity of Ketjenblack. Other types of carbon black include channel black, which is made by burning natural gas and scraping off the deposits that form on channel steel; acetylene black, which is obtained by thermally decomposing acetylene gas; and thermal black, which is produced by repeatedly burning and decomposing gas in a heat-storing furnace. Among carbon blacks, Ketjenblack has the smallest primary particles, the largest number of primary particles per unit mass, and the largest BET surface area, making it the most excellent light-blocking material. Therefore, when Ketjenblack is used as the carbon black, synthetic resin pellets are covered with aggregates of Ketjenblack, and a synthetic resin molded product is formed using the pellets, the molded product is resistant to deterioration even when continuously irradiated with ultraviolet light. Furthermore, Ketjenblack has a high thermal emissivity of 0.97, allowing the molded product to exhibit excellent heat dissipation properties. That is, Ketjen Black has a primary particle diameter of 30-40 nm, and therefore the number of primary particles per unit mass is 1 x 10 7 particles / g, with a BET surface area of ​​1270m 2 / g. Therefore, Ketjenblack has better light-blocking and heat-dissipating properties than other carbon blacks.

[0014] As stated in paragraph 6 mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets The method for producing the evenly coated pellets of the synthetic resin is as follows: The carbon black described in paragraph 6 is acetylene black, and the acetylene black is used as the carbon black described in paragraph 6, and the three steps described in paragraph 6 are carried out. All processing in the steps of: a) to agglomerate a synthetic resin pellets whose entire surfaces are evenly covered with a suspension of aggregates of acetylene black dispersed in alcohol; b) to agglomerate a synthetic resin pellets whose entire surfaces are evenly covered with a suspension of aggregates of carbon black dispersed in alcohol;

[0015] In other words, acetylene black is produced using acetylene gas, which has the highest purity among the raw materials for carbon black, and therefore has the fewest impurities among carbon blacks, and also has the most developed structure and primary particles. This gives it the best conductivity among carbon blacks. Therefore, synthetic resin pellets are covered with a collection of acetylene black aggregates, and a synthetic resin molded product made from these pellets has better conductivity, electromagnetic wave shielding properties, and antistatic properties than molded products made from other carbon blacks. For this reason, acetylene black is suitable for molding synthetic resin molded products with excellent conductivity. Note that, for example, acetylene black having a bulk density of 0.04 g / cm 3 There is a powder product with an electrical resistivity of 0.21 Ω·cm. The resistivity of copper is 1.68 x 10 ―6 Ω·cm, and if the resistivity of acetylene black is 0.21 Ω·cm as mentioned above and the specific conductivity of copper is 1.0, the specific conductivity of acetylene black is 8×10 ―6 The relative permeability of acetylene black is 1.0. On the other hand, the degree of reflection loss of electromagnetic waves is the ratio of specific conductivity to specific permeability, and the degree of absorption loss of electromagnetic waves is the ratio of specific conductivity to specific permeability. Therefore, the degree of reflection loss and absorption loss of electromagnetic waves of acetylene black are both 8 x 10 ―6 On the other hand, the specific conductivity of iron is 0.17 and the specific permeability is 100. Therefore, the degree of reflection loss of electromagnetic waves from iron is 1.7 × 10 ―3 The degree of electromagnetic wave absorption loss is 17. Therefore, acetylene black does not match the electromagnetic wave shielding performance of metals. Furthermore, antistatic performance is expressed by surface resistance. When a synthetic resin pellet is covered with a group of acetylene black aggregates to a thickness of 1 μm, the surface resistivity is 2.1 × 10 3 Ω / □. Also, when covered with a thickness of 0.1 μm, the surface resistivity is 2.1 × 10 4 Therefore, although both film thicknesses are difficult to charge, a thinner film made up of aggregates can dissipate static electricity more quickly.

[0016] As stated in paragraph 6 mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets The method for molding a synthetic resin molded body having light-shielding properties, heat dissipation properties, and electrical conductivity using a collection of the evenly covered synthetic resin pellets is as follows: The three steps described in paragraph 6 All processing inare carried out continuously, and the entire surface of the synthetic resin pellets is evenly covered with a suspension in which the aggregate groups are dispersed in alcohol. Thereafter, the pellet groups are filled into a molding machine or a mold, and the molding machine or the mold is heated to a temperature at which molding of the synthetic resin begins. The heating is continued for a predetermined time, and then a predetermined stress is applied to the heated pellet groups by the molding machine or the mold. At this time, the alcohol first evaporates from the suspension, and the aggregate groups are dispersed into the pellets. The aggregates are deposited on the surface of the pellet in an overlapping manner, and the aggregates cover the surface of the pellet evenly, and a plurality of areas on the surface of the pellet where the number of aggregates deposited in an overlapping manner is relatively small are formed. Thereafter, the pellet is heated to a temperature at which molding of the synthetic resin begins, and the heating is continued for a predetermined time, and a predetermined stress is applied to the pellet, which causes the pellet to thermally expand and a reaction caused by heating progresses in the pellet, and furthermore, stress is applied to the pellet, and the pellet subjected to the stress is The deformed pellets are deformed so as to fill the voids in the aggregate clusters, and further, the deformed pellets exude from the areas on the surface of the pellet where the number of aggregate clusters precipitated in an overlapping manner is relatively small. Furthermore, stress is continuously applied to the deformed pellets, and the exuded pellets from the adjacent deformed pellets bond together. As a result, the deformed pellets are evenly covered with the aggregate clusters precipitated in an overlapping manner, and the deformed pellets are bonded together by the bonding of the exuded pellets. The deformed pellets are bonded together, and a group of pellets in which the deformed pellets are bonded together is formed in the molding machine or the mold. Thereafter, the molding machine or the mold is cooled, and when the group of deformed pellets solidifies, the solidified pellets are evenly covered with the group of aggregates that have precipitated in an overlapping manner, and the exuded pellets also solidify, and the solidified pellets are bonded together by the bonding between the solidified exuded pellets, and a molded body consisting of the group of solidified pellets is molded in the molding machine or the mold. mosquito -A collection of aggregates of Bomb Black dispersed in alcohol as a suspension. The entire surface of the synthetic resin pellets A collection of pellets of the synthetic resin that are evenly covered is used to form a synthetic resin molded body that has light-shielding properties, heat dissipation properties, and electrical conductivity.

[0017] In other words, the present invention involves sequentially processing a collection of synthetic resin pellets through the three steps described in paragraph 6, and then using this collection of pellets to mold a molded body in accordance with conventional synthetic resin molding methods. When a collection of synthetic resin pellets is subjected to the three steps described in paragraph 6 in succession, the entire surface of the pellets is evenly covered with a suspension of aggregate clusters dispersed in alcohol. The collection of pellets is then loaded into a molding machine or mold. When the molding machine or mold is heated, the alcohol first evaporates from the suspension covering the pellet surface. This causes aggregate clusters to deposit on the pellet surface in a layered pattern. The aggregate clusters deposited on the pellet surface have very weak adhesion to the pellet surface and also very weak adhesion between the overlapping aggregate clusters. However, because the aggregate size is smaller than the pellet by at least one order of magnitude and the aggregate sizes vary, many areas on the pellet surface where the number of overlapping aggregate clusters is relatively small are formed. The collection of pellets is then heated in a molding machine or mold to a temperature at which the synthetic resin begins to form for a predetermined time. This causes the pellets to thermally expand, further promoting the reaction associated with heating. Stress is then applied to the pellet cluster using a molding machine or mold. At this time, the stressed pellets deform so as to fill the voids in the stressed pellet cluster. As described above, when the thermally expanded pellets deform, the aggregate clusters that have precipitated in an overlapping manner on the pellet surface have extremely weak bonding strength with the pellet surface, and the bonding strength between the overlapping aggregates is also extremely weak. Therefore, on the pellet surface, a portion of the stressed pellet exudes, pushing aside the overlapping aggregate clusters, from areas where the number of overlapping aggregate clusters is relatively small. The exuded pellet is then covered by the overlapping aggregate clusters, covering the exuded area. Therefore, the stressed pellet is evenly covered by the overlapping aggregate clusters. Meanwhile, pellets also exude from multiple locations on adjacent stressed pellets. When the exuded pellets come into contact with each other, the exuded pellets bond together due to the continued stress on the pellets.After this, when the molding machine or mold is cooled, the stressed pellets solidify, and the bonded oozing pellets solidify, and the solidified pellets bond together due to the bonding between the oozing pellets, and a compact consisting of a collection of solidified pellets is molded in the molding machine or mold. Meanwhile, because all of the solidified pellets are evenly covered with the collection of aggregates, the compact has the light-blocking, heat-dissipating, and electrical conductivity of the aggregates. As explained above, the compact produced by the present invention has all of the solidified pellets evenly covered with a collection of overlapping aggregates, and therefore has the properties of aggregates: light blocking, heat dissipation, and electrical conductivity. As a result, the three problems described in paragraph 5 are solved. [Brief explanation of the drawings]

[0018] [Figure 1] FIG. 1 is a diagram illustrating the side of a molded film made of pellets of PET resin covered with aggregates of Ketjen Black. DETAILED DESCRIPTION OF THE INVENTION

[0019] Embodiment 1 This embodiment relates to a synthetic resin whose molding-starting temperature is higher than the boiling point of the alcohol described in paragraph 9. The boiling point of the alcohol described in paragraph 9 is 82-138°C. First, we will explain thermoplastic resins that have a melting point higher than the boiling point of the alcohol described in paragraph 9. The melting point of low-density polyethylene resin is 95-130° C., and the melting point of high-density polyethylene resin is 120-140° C. Therefore, according to the melting point of the polyethylene resin, an alcohol having a boiling point lower than the melting point is selected from the alcohols listed in paragraph 9. The melting point of polypropylene resin is 168°C, and all of the alcohols listed in paragraph 9 have boiling points below 168°C. The glass transition temperature of polystyrene resin is 100°C, and an alcohol having a boiling point lower than 100°C is selected from the alcohols listed in paragraph 9. The glass transition temperature of the melting point of ABS resin is 100-110°C, and the alcohol having a boiling point lower than 100-110°C is selected from the alcohols listed in paragraph 9. The glass transition temperature of polyvinyl chloride resin is 85-210°C, and an alcohol having a boiling point lower than 85-210°C is selected from the alcohols listed in paragraph 9. The glass transition temperature of the acrylic resin is 90-105°C, and the alcohol having a boiling point lower than 90-105°C is selected from the alcohols listed in paragraph 9. The glass transition point of PET resin is 255°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 255°C. The melting point of PVA resin is 200°C, and all of the alcohols listed in paragraph 9 have boiling points below 200°C. The melting point of polyvinylidene chloride resin is 210°C, and all of the alcohols listed in paragraph 9 have boiling points below 210°C. The melting point of the polyvinylidene fluoride resin is 134-169°C, and the alcohol having a boiling point lower than 134-169°C is selected from the alcohols listed in paragraph 9. The melting point of nylon 6 resin is 225°C, and all of the alcohols listed in paragraph 9 have boiling points below 225°C. The melting point of nylon 66 resin is 265°C, and all of the alcohols listed in paragraph 9 have boiling points below 265°C. The melting point of nylon 12 resin is 176°C, and all of the alcohols listed in paragraph 9 have boiling points below 176°C. The melting point of polyacetal resin is 181°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 181°C. The glass transition temperature of polycarbonate resin is 150°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 150°C. The melting point of PBT resin is 232-267°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 232-267°C. The melting point of polyphenylene sulfide resin is 290°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 290°C. The glass transition temperature of polyetherimide resin is 215-217°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 215-217°C. The glass transition point of PS resin is 200°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 200°C. The melting point of PTFE resin is 327°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 327°C. The melting point of PCTFE resin is 220°C, and all of the alcohols listed in paragraph 9 have boiling points below 220°C. The melting point of PAI resin is 300°C, and all of the alcohols listed in paragraph 9 have boiling points below 300°C. As explained above, the melting points of most thermoplastic resins are lower than the boiling points of the alcohols described in paragraph 9, and therefore the alcohols described in paragraph 9 can be used as the alcohols having both properties described in paragraph 6. Therefore, pellets of most thermoplastic resins can be used when molding the synthetic resin molded article described in paragraph 14. Next, we will explain thermosetting resins whose polymerization reaction occurs at a temperature higher than the boiling point of the alcohol described in paragraph 9. The temperature at which the polymerization reaction of polyimide resin occurs is 211-267°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 211-267°C. The temperature at which the polymerization reaction of phenolic resin occurs is 161-211°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 161-211°C. The temperature at which the polymerization reaction of urea resin occurs is 153-193°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 153-193°C. The temperature at which the polymerization reaction of melamine resin occurs is 167-183°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 167-183°C. The polymerization reaction of unsaturated polyester resins occurs at a temperature of 156-195°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 156-195°C. The polymerization reaction of polyurethane resin occurs at a temperature of 84-120°C, and an alcohol with a boiling point lower than 84-120°C is selected from the alcohols listed in paragraph 9. The temperature at which the polymerization reaction of allyl resin occurs is 161-211°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 161-211°C. The temperature at which the polymerization reaction of silicone resin occurs is 154-182°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 154-182°C. The temperature at which the polymerization reaction of epoxy resin occurs is 167-183°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 167-183°C. The temperature at which the polymerization reaction of furan resin occurs is 153-195°C, and the boiling points of all the alcohols listed in paragraph 9 are lower than 153-195°C. As explained above, the temperature at which most thermosetting resins undergo polymerization reactions is lower than the boiling point of the alcohols described in paragraph 9, and therefore the alcohols described in paragraph 9 can be used as alcohols having both the properties described in paragraph 6. Therefore, pellets of most thermosetting resins can be used when molding the synthetic resin molded body described in paragraph 14.

[0020] Example 1 In this example, 1-propanol is used as the alcohol described in paragraph 11, Ketjenblack as described in paragraph 12 is used as the carbon black, and PET resin pellets are used as the synthetic resin pellets, and the surfaces of the PET resin pellets are coated with the suspension according to the method described in paragraph 6. The melting point of PET resin is 255°C. 1-propanol has a boiling point of 98°C and a viscosity of 1.9 mPa·s at 20°C. The Ketjen Black (product EC600JD by Lion Corporation) used had an average First order Particle size Size The specific surface area is 1270m 2 / g, which shows excellent light-blocking properties. Furthermore, the amount of dibutyl phthalate required to fill the gaps between Ketjen Black particles is 495 cm 3 / 100g, which is large, and the degree of particle connection and particle aggregation is large. This promotes entanglement of Ketjen Black aggregates, resulting in excellent light-blocking properties. The pellets used (e.g., products from Mitsubishi Chemical Corporation) have a shape of an elliptical cylinder measuring 2mm x 4mm x 3mm, and a density of 1.36g / cm 3 The weight of one pellet corresponds to 25.6 mg. First, 10 g of Ketjen Black and 80 g of 1-propanol were charged into a container, and the 1-propanol was stirred to immerse the Ketjen Black in the 1-propanol. After this, a flat plate was placed on top of the container, and nine 2 kg weights were placed on the plate at equal intervals. The weights and plate were then removed, and the container was fixed on a vibration table. An acceleration of 2 G was repeatedly applied to the container in three directions: front-back, left-right, and up-down. This pair of processes, consisting of applying a compressive load and applying an acceleration, was repeated five times, after which the weight was placed on the plate. However, since there was no movement of the plate, the pair of processes was stopped. Furthermore, an ultrasonic homogenizer (LUH150, product of Yamato Scientific Co., Ltd.) was operated in the 1-propanol in the container, and a 20 kHz ultrasonic signal was applied for 10 minutes to create a suspension in which aggregates entangled with each other through the 1-propanol were dispersed in the 1-propanol. Thereafter, 60 g of PET resin pellets were placed in the container, and the pellet collection was stirred and immersed in the suspension, after which the pellet collection was removed from the container.

[0021] Example 2 A film having a thickness of 0.1 mm was formed by calendar molding using a T-die casting method using the collection of PET resin pellets covered with the suspension produced in Example 1. The formed film had a pale blackish transparency. Next, the film was cut and the cross section was observed using an electron microscope. An ultra-low accelerating voltage SEM owned by JFE Techno-Research Corporation was used for the electron microscope. This device allows surface observation at ultra-low accelerating voltages starting from 100V, and furthermore, allows the surface of the sample to be observed directly without forming a conductive coating. The secondary electron beam between 900-1000V was extracted from the reflected electron beam from the cross section and image processing was performed. The film was 0.1mm thick. The cross section showed that the surface of the flattened pellet was covered with a collection of Ketjen Black aggregates with a thickness of 1μm, and adjacent pellets were joined by a pellet of a small thickness. Figure 1 shows a schematic diagram of the cross section. 1 is a pellet of PET resin, and 2 is a collection of Ketjen Black aggregates. Furthermore, the light-shielding properties of the film were measured according to JIS-L-1055A and found to have a light-shielding rate of 95%, making it an excellent light-shielding sheet. Furthermore, the thermal emissivity of the sheet was measured using an analyzer consisting of a Fourier transform infrared spectrophotometer and a radiation measurement unit (equipment owned by Kobelco Research Institute, Inc.), and it was found to have a high thermal emissivity of 0.93, making it an excellent heat dissipation sheet.

[0022] Example 3 In Example 1, the surface of a PET resin pellet was coated with a suspension of aggregates of Ketjen Black dispersed in 1-propanol. In Example 3, the surface of a PET resin pellet was coated with a suspension of aggregates of acetylene black (Li-100, a product of Denka Co., Ltd.) dispersed in 1-butanol. 1-butanol has a viscosity of 3.0 mPa·s at 20°C and a boiling point of 117°C. Therefore, the viscosity of 1-butanol is 1.7 times that of 1-propanol, and the thickness of the suspension coating the surface of the PET resin pellet increases by 1.7 times as the viscosity increases. First, 10 g of acetylene black and 80 g of 1-butanol were charged into a container, and the 1-butanol was stirred to immerse the acetylene black in the 1-butanol. Then, as in Example 1, a flat plate was placed on top of the container, and nine 2 kg weights were placed on the plate at equal intervals. The weights and plate were then removed, and the container was fixed on a vibration table. An acceleration of 2 G was repeatedly applied to the container in three directions: front-back, left-right, and up-down. This pair of processes, consisting of a process of applying a compressive load and a process of applying an acceleration, was repeated five times, after which a weight was placed on the plate. However, since there was no movement of the plate, the pair of processes was stopped. Furthermore, as in Example 1, an ultrasonic homogenizer was operated in the 1-butanol in the container, and a 20 kHz ultrasonic signal was applied for 10 minutes to create a suspension in which aggregates entangled with each other through the 1-butanol were dispersed in the 1-butanol. Thereafter, 60 g of the PET resin pellets used in Example 1 were placed in the container, and the pellet collection was stirred and immersed in the suspension, after which the pellet collection was removed from the container.

[0023] Example 4 A sheet having a thickness of 0.3 mm was formed by calendar molding using a collection of PET resin pellets covered with the suspension produced in Example 3. The formed sheet had a darker color than the film of Example 2, but still retained transparency. Next, the sheet was cut in the same manner as in Example 2, and the cross section was observed using the electron microscope used in Example 2. Regarding the reflected electron beam from the cross section, secondary electron beams between 900-1000V were extracted and image processing was performed. The thickness of the sheet was 0.3 mm. In the cross section, the surface of the flattened pellets was covered with a collection of acetylene black aggregates with a thickness of 1.7 μm, and adjacent pellets were joined by pellets with a small thickness. Next, the surface resistance of the created sheet was measured at multiple points using a surface resistance meter (for example, a surface resistance meter ST-4 from Simco Japan Co., Ltd.). The surface resistivity was 1.0 Ω, meaning that the sheet had a resistance close to the resistivity of acetylene black, which is 0.21 Ω·cm. Therefore, based on the resistivity of acetylene black, the created sheet also functions as a thin film that combines the functions of conductivity, electromagnetic wave shielding, and antistatic properties.

[0024] Example 5 In this example, the suspension prepared in Example 1 is used to cover the surface of phenolic resin pellets. As the phenolic resin pellets, pellets with a softening point of 125°C and gelling at 150°C in about 80 seconds (for example, AH-PM(H) manufactured by Meiwa Kasei Co., Ltd.) are used. Furthermore, Ketjen Black from Example 1 is used as the carbon black. First, 10 g of acetylene black and 80 g of 1-butanol were charged into a container, and the 1-butanol was stirred to immerse the acetylene black in the 1-butanol. Then, as in Example 1, a flat plate was placed on top of the container, and nine 2 kg weights were placed on the plate at equal intervals. The weights and plate were then removed, and the container was fixed on a vibration table. An acceleration of 2 G was repeatedly applied to the container in three directions: front-back, left-right, and up-down. This pair of processes, consisting of a process of applying a compressive load and a process of applying an acceleration, was repeated five times, after which a weight was placed on the plate. However, since there was no movement of the plate, the pair of processes was stopped. Furthermore, as in Example 1, an ultrasonic homogenizer was operated in the 1-butanol in the container, and a 20 kHz ultrasonic signal was applied for 10 minutes to create a suspension in which aggregates entangled with each other through the 1-butanol were dispersed in the 1-butanol. Then, 60 g of the PET resin pellets used in Example 1 were placed in a container, the pellets were stirred, and the pellets were immersed in the suspension. The pellets were then removed from the container. A sheet with a thickness of 0.5 mm was formed using this pellet collection by extrusion molding. The molded sheet had a higher blackness than the sheet of Example 4. Next, the sheet was cut, and the cross section was observed using the electron microscope used in Example 2. Regarding the reflected electron beam from the cross section, a secondary electron beam between 900-1000V was extracted and image processing was performed. The thickness of the sheet was 0.5 mm. In the cross section, the surface of the flattened pellets was covered with a collection of 1.7 μm thick Ketjen Black aggregates, and adjacent pellets were joined by pellets of a small thickness. Furthermore, the light-shielding properties of the film were measured according to JIS-L-1055A and found to have a light-shielding rate of 96%, making it an excellent light-shielding sheet. Furthermore, the thermal emissivity of the sheet was measured using an analyzer consisting of a Fourier transform infrared spectrophotometer and a radiation measurement unit (equipment owned by Kobelco Research Institute, Inc.), and it was found to have a high thermal emissivity of 0.94, making it an excellent heat dissipation sheet.

[0025] The above-described examples are only a few examples. In other words, suspensions having various compositions can be prepared by using the alcohol described in paragraph 11, Ketjen Black described in paragraph 13, or Acetylene Black described in paragraph 15 as carbon black, and following the method for preparing a suspension described in paragraph 6. Furthermore, pellets of various synthetic resins described in Embodiment 1, not limited to the PET resin pellets and phenolic resin pellets described in the examples, can be coated with suspensions of various compositions. Molded articles made of various synthetic resins can be obtained by molding a collection of pellets coated with this suspension according to the conventional molding method for synthetic resins described in paragraph 16. These molded articles have the properties of the carbon black used. [Explanation of symbols]

[0026] 1. PET resin pellets 2. Ketjenblack aggregates

Claims

1. A method for preparing a collection of synthetic resin pellets in which the entire surface of the synthetic resin pellets is evenly covered with a suspension in which a collection of carbon black aggregates is dispersed in alcohol is as follows: a predetermined weight of liquid alcohol having a first property of having a viscosity of 2-3 mPa·sec at 20°C and a second property of having a boiling point lower than the temperature at which synthetic resin molding begins is placed in a container, and a smaller weight of carbon black aggregates than the alcohol is placed in the container, and the alcohol is stirred to prepare a first suspension in which the carbon black aggregates are immersed in the alcohol; thereafter, a plate that covers the entire surface of the first suspension is placed over the first suspension; a compressive load is applied evenly to the entire surface of the plate to pulverize the carbon black aggregates immersed in the alcohol; the plate is then lifted from the first suspension, and the container is placed on a vibration table of a vibrator; the vibrator is operated to repeatedly apply acceleration in three directions, i.e., forward / backward, left / right, and up / down, to the container, thereby rearranging the pulverized carbon black aggregates in the alcohol; the plate is then covered with the first suspension again, and the compressive load is again applied evenly to the entire surface of the plate, further pulverizing the carbon black agglomerates immersed in the alcohol; the plate is then lifted out of the first suspension again, and the acceleration in the three directions is again repeatedly applied to the container; this pair of processes consisting of the process of applying the compressive load and the process of applying the acceleration is repeated on the container; when the compressive load is applied to the plate, and the pulverization of the carbon black by compression of the plate reaches a limit, even if the pulverized carbon black is compressed, a repulsive force is generated in the plate; when the repulsive force is generated in the plate, it is determined that the pulverization of the carbon black agglomerates immersed in the alcohol has been completed, and the pair of processes is stopped; and then, the plate is removed from the container; a second step of disposing an ultrasonic homogenizer in the container, operating the homogenizer, repeatedly applying shock waves to the aggregates of the pulverized carbon black via the alcohol, separating entanglements of aggregates in the pulverized carbon black, allowing the alcohol to be adsorbed onto the separated sites, entangling the aggregates with each other via the alcohol, and preparing a second suspension consisting of the aggregates entangled with each other via the alcohol; a third step of introducing into the container a collection of synthetic resin pellets having a weight less than the weight of the second suspension in the container, stirring the collection of synthetic resin pellets, and immersing the collection of synthetic resin pellets in the second suspension; thereafter, removing the collection of synthetic resin pellets from the container; thereby causing the second suspension to be adsorbed onto the entire surfaces of the synthetic resin pellets to a thickness corresponding to the viscosity of the second suspension, thereby creating a collection of synthetic resin pellets whose entire surfaces are evenly covered with the second suspension; A method in which all of the treatments in the above three steps are carried out continuously produces a collection of synthetic resin pellets in which the entire surface of the synthetic resin pellets is evenly covered with a suspension in which collections of carbon black aggregates are dispersed in alcohol.

2. A method for preparing a collection of synthetic resin pellets in which the entire surface of the synthetic resin pellets is evenly covered with a suspension in which the collection of carbon black aggregates described in claim 1 is dispersed in alcohol, comprising: The alcohol described in claim 1 has the following three properties related to boiling point: the first boiling point is a boiling point property when pellets of a thermosetting resin are used as the synthetic resin pellets described in claim 1, and the first boiling point is lower than the temperature at which a polymerization reaction of the thermosetting resin occurs; the second boiling point is a boiling point property when pellets of a non-crystalline thermoplastic resin are used as the synthetic resin pellets described in claim 1, and the second boiling point is lower than the glass transition point of the non-crystalline thermoplastic resin; and the third boiling point is a boiling point property when pellets of a crystalline thermoplastic resin are used as the synthetic resin pellets described in claim 1. a third boiling point being a boiling point property when the crystalline thermoplastic resin is dissolved in the alcohol, and the third boiling point is lower than the melting point of the crystalline thermoplastic resin; and by selectively using alcohols having the three properties related to these boiling points depending on the material of the synthetic resin pellets described in claim 1 and continuously performing all of the treatments in the three steps described in claim 1, the entire surface of the synthetic resin pellets is evenly covered with a suspension in which clusters of carbon black aggregates are dispersed in alcohol, a method for producing aggregates of synthetic resin pellets in which the entire surface of the synthetic resin pellets is evenly covered with the suspension in which clusters of carbon black aggregates are dispersed in alcohol described in claim 1.

3. A method for preparing a collection of synthetic resin pellets in which the entire surface of the synthetic resin pellets is evenly covered with a suspension in which the collection of carbon black aggregates described in claim 1 is dispersed in alcohol, comprising: A method for producing aggregates of synthetic resin pellets, the entire surfaces of which are evenly covered with a suspension in which aggregates of carbon black are dispersed in alcohol, as set forth in claim 1, wherein the liquid alcohol having the two properties set forth in claim 1 is any one of 2-propanol, 1-propanol, 1-butanol, and 1-pentanol, and the any one of the alcohols is used as the liquid alcohol having the two properties set forth in claim 1, and all of the treatments in the three steps set forth in claim 1 are carried out continuously, thereby causing the entire surfaces of the synthetic resin pellets to be evenly covered with a suspension in which aggregates of carbon black are dispersed in alcohol.

4. A method for preparing a collection of synthetic resin pellets in which the entire surface of the synthetic resin pellets is evenly covered with a suspension in which the collection of carbon black aggregates described in claim 1 is dispersed in alcohol, comprising: A method for producing aggregates of synthetic resin pellets, the entire surfaces of which are evenly covered with a suspension in which aggregates of Ketjenblack are dispersed in alcohol, comprising the steps of: using the carbon black described in claim 1 as the carbon black described in claim 1; and continuously performing all of the treatments in the three steps described in claim 1, so that the entire surfaces of the synthetic resin pellets are evenly covered with a suspension in which aggregates of Ketjenblack are dispersed in alcohol.

5. A method for preparing a collection of synthetic resin pellets in which the entire surface of the synthetic resin pellets is evenly covered with a suspension in which the collection of carbon black aggregates described in claim 1 is dispersed in alcohol, comprising: A method for producing aggregates of synthetic resin pellets, the entire surfaces of which are evenly covered with a suspension in which aggregates of acetylene black are dispersed in alcohol, wherein the carbon black according to claim 1 is acetylene black, and all of the three steps according to claim 1 are continuously performed, thereby evenly covering the entire surfaces of the synthetic resin pellets with the suspension in which aggregates of acetylene black are dispersed in alcohol.

6. A method for molding a synthetic resin molding having light-shielding, heat-dissipating, and conductive properties using a collection of synthetic resin pellets whose entire surfaces are evenly covered with a suspension in which the collection of carbon black aggregates described in claim 1 is dispersed in alcohol, comprising: All the treatments in the three steps described in claim 1 are carried out continuously, and the entire surface of the synthetic resin pellets is evenly covered with a suspension of aggregates dispersed in alcohol. Thereafter, the pellets are filled into a molding machine or a mold, and the molding machine or the mold is heated to a temperature at which molding of the synthetic resin begins. The heating is continued for a predetermined time, and then a predetermined stress is applied to the heated pellets by the molding machine or the mold. At this time, the alcohol is first dispersed from the suspension. The pellet vaporizes, and aggregates of the aggregates are deposited on the surface of the pellet in a piled-up state, covering the surface of the pellet evenly, and a plurality of portions on the surface of the pellet where the number of aggregates deposited on top of each other is relatively small are formed. Thereafter, the pellet is heated to a temperature at which molding of the synthetic resin begins, and the heating is continued for a predetermined time. Furthermore, a predetermined stress is applied to the pellet, which causes the pellet to thermally expand and a reaction due to heating progresses in the pellet, and further, the pellet is heated. Stress is applied to the pellet, and the pellet subjected to the stress is deformed so as to fill the gaps in the pellet clusters. Furthermore, a part of the deformed pellet exudes from the surface of the pellet where the number of aggregate clusters precipitated in an overlapping manner is relatively small. Furthermore, stress is continuously applied to the deformed pellet, and the pellets exuded from the adjacent deformed pellets are bonded together. As a result, the deformed pellet is evenly covered with the aggregate clusters precipitated in an overlapping manner, and the deformed pellets are bonded together. The exuded pellets are bonded together by bonding between the exuded pellets, and a group of pellets in which the deformed pellets are bonded together is formed in the molding machine or the mold. Thereafter, the molding machine or the mold is cooled, and the group of deformed pellets is solidified. The solidified pellets are evenly covered with the group of aggregates that have precipitated in an overlapping manner, and the exuded pellets also solidify. The solidified exuded pellets are bonded together by bonding between the solidified exuded pellets, and a molded body consisting of the group of solidified pellets is formed.A method for molding a synthetic resin molded article having light-shielding properties, heat dissipation properties, and electrical conductivity, using a collection of synthetic resin pellets in which the entire surfaces of the synthetic resin pellets are evenly covered with a suspension in which the collection of carbon black aggregates according to claim 1 is dispersed in alcohol, the collection of synthetic resin pellets being molded in the molding machine or the mold.

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