Silicon oxynitride-containing composition, heat-dissipating resin composition, and heat-dissipating resin composition film sheet using the same.

Abstract

To provide a silicon oxynitride-containing composition having excellent heat radiation properties (radiation cooling effect), a heat-radiating resin composition and a heat-radiating resin film or a heat-radiating resin sheet.SOLUTION: A silicon oxynitride-containing composition comprises silicon oxynitride of 50 mass% or more in the solid content 100 mass% of the silicon oxynitride-containing composition.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to, for example, a method for preparing a silicon oxynitride-containing composition that imparts heat dissipation properties or improves heat dissipation properties to an existing resin with low thermal conductivity, and a heat dissipation film and a heat dissipation sheet obtained by containing this in a resin substrate, and a method for producing the same.

Background Art

[0002] In recent years, from the viewpoint of improving comfort in the living environment of humans, the breeding environment of animals, or the growth environment of plants, etc., and achieving cold storage of foods, etc. with less energy consumption, the development of various heat dissipation materials has been underway.

[0003] For example, when considering a heat dissipation sheet used in an agricultural greenhouse, a resin sheet (heat insulation sheet) having a heat insulation performance that does not increase the temperature inside the greenhouse is common. As such a heat insulation sheet, Patent Document 1 discloses an agricultural heat insulation film using a synthetic resin containing tungsten oxide as inorganic particles (for example, see Patent Document 1). In recent years, the heat insulation properties of a radiative cooling material using a radiative cooling effect have also been disclosed (for example, see Patent Documents 2, Patent Documents 3, Patent Documents 4, Non-Patent Document 1, Non-Patent Document 2). The radiative cooling effect, which is a technical feature of these documents, is the use of heat radiation in the 8 to 13 μm wavelength region, so-called "atmospheric window", that is, heat radiation by wavelength-selective heat radiation, for cooling of substances.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

[0005] [Non-Patent Document 1] Science 1062 Vol.355 Issue 6329 2017 [Non-Patent Document 2] Journal of the Ceramic Society of Japan 124 (11) 1185-1187 2016 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, regarding these heat dissipation methods, for example, in Patent Document 1, tungsten oxide used for heat shielding has a photocatalytic effect, and therefore, when mixed with synthetic resin, there was concern that it would accelerate the degradation of the synthetic resin to some extent. Furthermore, Tempax (registered trademark) (product name: borosilicate glass) used in the heat dissipation layer in Patent Documents 2 and 3, and silica (SiO2) used as a heat dissipation component in Non-Patent Document 1, have absorption wavelengths originating from silicon-oxygen bonding concentrated in two areas, 9 μm and 13 μm, within the "atmospheric window" wavelength range, making it theoretically difficult to say that they are sufficient for the effective manifestation of radiative cooling. Moreover, although silicon oxynitride is used in Non-Patent Document 2, the thin film formation using the special method of electrodeposition with nanoparticles is complicated, and there was concern that it would peel off when used as a component. In Patent Document 4, the resin used for the film was not sufficiently considered. The object of the present invention is to provide a silicon oxynitride-containing composition, a heat-dissipating resin composition, and a heat-dissipating resin film or heat-dissipating resin sheet that have excellent thermal radiation properties (radiative cooling effect). [Means for solving the problem]

[0007] Therefore, in order to solve the above problems, we proposed and investigated a silicon oxynitride-containing composition and a heat-dissipating resin film sheet containing silicon oxynitride, which have good thermal conductivity and a broad absorption band in the "atmospheric window" wavelength region. As a result, we found that the problems of the present invention can be solved by a silicon oxynitride-containing composition mainly composed of silicon oxynitride (Si2N2O), a heat-dissipating resin film sheet containing the same, and a method for producing the same, including the inventions described in [1] to

[10] below. The present invention includes, for example, the following [1] to

[10] . [1] A silicon oxynitride-containing composition containing 50% by mass or more of silicon oxynitride in 100% by mass of the solid content of the silicon oxynitride-containing composition. [2] The silicon oxynitride-containing composition of [1] further comprising at least one selected from the group consisting of silicon nitride, silicon monoxide, and silicon dioxide. [3] A silicon oxynitride-containing composition of [1] or [2] further comprising a liquid. [4] A silicon oxynitride-containing composition of any of [1] to [3] used in the manufacture of a heat-dissipating resin composition for forming a film or sheet. [5] A silicon oxynitride-containing composition according to any of [1] to [4], wherein the 50% diameter (D50) of the silicon oxynitride is 100 μm or less. [6] A heat-dissipating resin composition comprising silicon oxynitride and a resin, wherein the heat-dissipating resin composition contains 0.5 to 15.0% by mass of silicon oxynitride in 100% by mass of the heat-dissipating resin composition. [7] A heat-dissipating resin composition further comprising at least one selected from the group consisting of silicon nitride, silicon monoxide and silicon dioxide. [5] [8] The heat-dissipating resin composition of [4] or [5], wherein the resin is at least one selected from the group consisting of polyolefins and polyamides. [9] A heat-dissipating resin composition of any of [6] to [8], wherein the 50% diameter (D50) of silicon oxynitride is 100 μm or less. A heat-dissipating resin film or heat-dissipating resin sheet comprising any of the heat-dissipating resin compositions of

[10] , [6], to [9].

[11] A heat-dissipating resin film or sheet of

[10] having a thickness of 0.01 to 3 mm. [Effects of the Invention]

[0008] The silicon oxynitride-containing composition, heat-dissipating resin composition, and heat-dissipating resin film sheet of the present invention are excellent in heat radiation properties (radiative cooling effect). [Brief Description of the Drawings]

[0009] [Figure 1] XRD analysis data of silicon oxynitride used in the present invention [Figure 2] IR data of the heat-dissipating resin film sheet obtained in Example 7 [Figure 3] Top view and A-A' cross-sectional view of the temperature measuring device used in the present invention [Figure 4] Heat dissipation measurement data of Example 3 [Figure 5] Heat dissipation measurement data of Example 5 [Figure 6] Heat dissipation measurement data of Example 7 [Figure 7] Heat dissipation measurement data of Comparative Example 1 [Figure 8] Appearance photograph of Example 3 (after outdoor evaluation) [Figure 9] Appearance photograph of Example 5 (after outdoor evaluation) [Modes for Carrying Out the Invention]

[0010] The first aspect of the present invention is a silicon oxynitride-containing composition containing 50% by mass or more of silicon oxynitride in 100% by mass of the solid content of the silicon oxynitride-containing composition.<x The second aspect of the present invention is a heat-dissipating resin composition containing silicon oxynitride and a resin, and is a heat-dissipating resin composition containing 0.5 to 15.0% by mass of silicon oxynitride in 100% by mass of the heat-dissipating resin composition.

[0011] [<The First Aspect of the Present Invention>] The first aspect of the present invention is a silicon oxynitride-containing composition containing 50% by mass or more of silicon oxynitride in 100% by mass of the solid content of the silicon oxynitride-containing composition. [Silicon Oxynitride-Containing Composition] Silicon oxynitride-containing compositions are preferably used to impart heat dissipation properties to resin films or resin sheets, and are also called heat dissipation fillers. In the present invention, the silicon oxynitride-containing composition used to produce heat-dissipating resin film sheets is a composition mainly composed of silicon oxynitride (Si2N2O, sometimes referred to as SiON) (SiON content: 50% or more), and may be a powder composition, a granular composition, or a slurry composition. The silicon oxynitride-containing composition preferably further contains at least one silicon-based compound selected from the group consisting of silicon nitride (Si3N4), silicon monoxide (SiO), and silicon dioxide (silica: SiO2). Furthermore, in the case of a slurry composition, it is preferable to further contain a liquid.

[0012] <Main component: Silicon oxynitride> Silicon oxynitride (Si2N2O), the main component of silicon oxynitride-containing compositions, exhibits a radiative cooling effect and is a chemically resistant oxynitride due to its broad absorption range in the wavelength region of 8-13 μm, known as the "atmospheric window." Silicon oxynitride can be obtained by calcining silicon and silicon dioxide at high temperatures under a nitrogen atmosphere; for example, the manufacturing method disclosed in Japanese Patent Application Publication No. 2021-34587 can be employed.

[0013] <Silicon-based compounds> The silicon oxynitride-containing composition of the present invention may contain a silicon-based compound as an optional component. Examples of silicon-based compounds include one or more selected from silicon nitride (Si3N4), silicon monoxide (SiO) and silicon dioxide (silica:SiO2). The silicon-based compound is added with the aim of increasing the amount of absorption in the aforementioned "atmospheric window" absorption region by including a compound with an absorption wavelength different from that of silicon oxynitride in the aforementioned "atmospheric window" absorption region, that is, increasing the amount of radiation according to Kirchhoff's law of heat, and thereby making radiative cooling (thermal radiation) more effective. Note that silicon nitride, silicon monoxide, and silicon dioxide may be used as commercially available products, or they may be prepared and processed separately, for example, by granulation (aggregation, pulverization), before use.

[0014] (Content) In the silicon oxynitride-containing composition used in the present invention, the content of silicon oxynitride (main component) and silicon-based compounds (optional components) are set depending on heat dissipation, ease of dispersion into the resin substrate described later, durability, and cost. Therefore, from these viewpoints, the content of silicon oxynitride is 50% by mass or more, preferably 100% by mass or less, more preferably 75 to 100% by mass, even more preferably 85 to 100% by mass, and particularly preferably 95 to 99.99% by mass, based on 100% by mass of the solid content of the silicon oxynitride-containing composition. Here, solid content refers to components that are solid at room temperature. The content of silicon-based compounds in the silicon oxynitride-containing composition is preferably 0 to less than 50% by mass, more preferably 0.01 to 20% by mass, and particularly preferably 0.5 to 15% by mass, based on 100% by mass of the solid content of the silicon oxynitride-containing composition.

[0015] (Particle size of silicon oxynitride and silicon-based compounds) In this invention, it is desirable to use granulated and / or classified silicon oxynitride (main component) and silicon-based compounds for the purpose of improving heat dissipation. The 50% diameter (D50; median diameter) of the silicon oxynitride or silicon-based compound used in this invention, when used in a film sheet as described later, is less than or equal to the thickness of the film sheet that is normally created, but is preferably 100 μm or less, more preferably 40 μm or less, even more preferably 10 μm or less, preferably 0.01 μm or more, more preferably 0.1 μm or more, and particularly preferably 1 to 5 μm. Furthermore, the 90% diameter (D90; particle size where the proportion of particles smaller than or equal to this particle size is 90%) of the silicon oxynitride used, when used in a film sheet as described later, is less than or equal to the thickness of the film sheet that is normally created, but is preferably 500 μm or less, more preferably 300 μm or less, preferably 0.01 μm or more, and more preferably 0.1 μm or more. Furthermore, particle size within the above range is preferable from the viewpoint of heat dissipation and visibility (transparency, color) when made into sheets or films. Here, the particle size of the silicon oxynitride-containing composition is a value measured by laser diffraction.

[0016] (Slurry-type silicon oxynitride-containing composition) The silicon oxynitride-containing composition is also preferably in the form of a slurry containing a liquid. Examples of the liquid include water and organic solvents, but water and alcohols are preferred. As the alcohol, for example, ethanol, methanol, isopropanol, polyvinyl alcohol, etc. can be used, with ethanol and polyvinyl alcohol being preferred. If a slurry is to be formed, an acid can also be used, for example, mineral acids such as hydrochloric acid and sulfuric acid, or organic acids such as acetic acid. The pH of the slurry-like silicon oxynitride-containing composition (slurry-like silicon oxynitride-containing composition) is preferably, for example, 0.1 to less than 8, and more preferably 1 to less than 8. The content of the silicon oxynitride composition in the slurry-like silicon oxynitride-containing composition is not particularly limited, but from the viewpoint of dispersibility and economic efficiency of not using too much liquid, it is preferably 0.01 to 60% by mass, and more preferably 3 to 20% by mass.

[0017] <Additives> Furthermore, the silicon oxynitride-containing composition may contain the following additives as optional components, to the extent that they do not significantly impede the heat dissipation effect of the present invention. Examples of additives used in the silicon oxynitride-containing composition include inorganic compounds (aluminum oxide (Al2O3), zircon oxide (ZrO2), hafnium oxide (HfO2), magnesium oxide (MgO), titanium oxide (TiO2), vanadium oxide (VO2,V2O5), boron oxide (BO3), talc, kaolin, etc. or oxides (metal oxides, nonmetal oxides); sodium carbonate, potassium carbonate, cesium carbonate, potassium chloride, sodium chloride, potassium bromide, potassium iodide, sodium iodide, potassium sulfate, sodium sulfate, etc. The material may appropriately contain known additives for heat-shielding and light-shielding substrates, such as alkaline earth metal salts (calcium carbonate, magnesium carbonate, calcium chloride, magnesium chloride, barium sulfate, magnesium sulfate, etc.; phosphates such as magnesium hydrogen phosphate, magnesium hydrogen phosphate, etc.), light stabilizers, antioxidants, anti-aging agents, heat-resistant stabilizers, colorants (e.g., pigments and dyes), lubricants, fillers, antistatic agents, slip agents, antiblocking agents, fibrous reinforcements, particulate reinforcements, plasticizers, foaming agents, weathering agents, nucleating agents, crystallization accelerators, mold release agents, flame retardants, flame retardant aids, etc. These additives may be commercially available or separately synthesized preparations. Furthermore, commercially available products or preparations may be processed, for example, by granulation (aggregation, pulverization) before use.

[0018] (Particle size: additive) Of the above additives, those that require particle size adjustment before use should be prepared, for example, by referring to the particle size of the silicon oxynitride-containing composition.

[0019] (Content: Additives) In the additives used in the present invention, the content of silicon oxynitride in the silicon oxynitride-containing composition is set as described above, according to the presence or absence of coloring, transparency, intended use, usage conditions, and usage environment of the heat-dissipating resin film sheet made using it. Therefore, under conditions that do not hinder these, it may be used in amounts of 100 parts by mass or more relative to the amount of silicon oxynitride used. However, for example, when making a transparent heat-dissipating resin film sheet using titanium dioxide (rutile type) as an additive, the amount of titanium dioxide used is preferably 3% by mass or less, more preferably 1.0% by mass or less, even more preferably 0.5% by mass or less, particularly preferably 0.3% by mass or less, and preferably 0.01% by mass or more, per 100% by mass of the resin. With this amount, it is possible to contribute to sufficient heat dissipation for outdoor use without impairing the transparency of the heat-dissipating resin film sheet.

[0020] [Manufacturing method: Silicon oxynitride-containing composition] Silicon oxynitride-containing compositions are manufactured by mixing silicon oxynitride, and optionally the silicon-based compounds and additives. The method of mixing these components is not particularly limited, as it varies depending on the product being manufactured. If the silicon oxynitride-containing composition is in powder form, for example, the silicon oxynitride and the silicon-based compounds and / or additives are mixed by methods such as shaking, stirring, or ball milling, and then classified by sieving as necessary to obtain a powdered silicon oxynitride-containing composition. If the composition is in slurry form, the silicon oxynitride and any of the silicon-based compounds and / or additives are dispersed in a liquid (water, organic solvent, etc.) in which these substances do not react, and then further wet-milled as necessary, and classified by sieving as necessary to obtain a slurry-like silicon oxynitride-containing composition. If the composition is in granular form, it can be manufactured by distilling off the liquid from the slurry-like silicon oxynitride-containing composition and drying it to obtain granules.

[0021] [Application] The silicon oxynitride-containing composition is used as a composition that imparts thermal radiation properties in the manufacture of heat-dissipating resin compositions for film or sheet formation. Specifically, it is suitably used in the manufacture of the heat-dissipating resin composition of the second aspect of the present invention described later, and the heat-dissipating resin film or heat-dissipating resin sheet obtained from said heat-dissipating resin composition.

[0022] <<Second aspect of the present invention>> [Heat dissipating resin composition] A second aspect of the present invention is a heat-dissipating resin composition comprising silicon oxynitride and a resin, wherein the heat-dissipating resin composition contains 0.5 to 15.0% by mass of silicon oxynitride in 100% by mass of the heat-dissipating resin composition. Embodiments of the heat-dissipating resin composition include solids and slurries, and the solid form can be in the form of a normal concentration or a masterbatch.

[0023] <Resin> The resin is not particularly limited, but it is preferably a resin that can be molded into independently shape-retaining (self-supporting or shape-independent) films or sheets. Furthermore, from the viewpoint of not overlapping with the atmospheric window, it is preferable that the resin does not have an absorption wavelength in the 8-13 μm range, and even if there is an absorption wavelength in this range, it is preferable that the absorbance measured by infrared spectroscopy (IR) is 0.2 or less.Therefore, as these resin substrates, for example, polyolefins, polyamides, ethylene-vinyl acetate copolymers (EVA), chlorine-containing resins (polyvinyl chloride, polyvinylidene chloride, etc.), polyesters (polyethylene terephthalate, polylactic acid, polybutylene succinate, etc.), acrylic resins (polyacrylate, polymethacrylate, etc.), cellulose resins (cellulose, triacetylcellulose, etc.) can be used. These can be used individually or in combination of two or more.

[0024] Examples of polyolefins include polystyrene (isotactic, atactic, syndiotactic), polypropylene (isotactic, atactic, syndiotactic), polymethylpentene, low-density polyethylene (LDPE) film, linear low-density polyethylene (LLDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE) and copolymers of their constituent monomers, cyclic polyolefins (COP) such as polynorbornene and ethylene-propylene-5-ethylidene-2-norbornene copolymer, and copolymers of their constituent monomers (COC).

[0025] Examples of polyamides include aliphatic polyamides such as nylon 6, nylon 66, and nylon 12, and aliphatic copolymer polyamides such as nylon 6 / 12 and nylon 6 / 66 / 12; partially aromatic polyamides such as polyamide 6T, polyamide 9T, and polyamide MXD6; and aromatic polyamides such as poly(p-phenylene terephthalamide). Among these, aliphatic polyamides are preferred from the viewpoint of photostability.

[0026] Among these resins, polyolefins, polyesters, polyamides, ethylene-vinyl acetate copolymers (EVA), and acrylic resins are preferred from the viewpoint of the intensity and region of absorption wavelengths, polyolefins, polyamides, and ethylene-vinyl acetate copolymers (EVA) are more preferred, polyolefins and polyamides are even more preferred, and polyethylene, polypropylene, and polyamide 6 are particularly preferred. For example, resin substrates such as polyethylene and polyamide 6 have almost no absorption wavelengths in the so-called "atmospheric window" wavelength region, or their absorption is weak, so they are considered useful for heat dissipation because they have less interference with radiant heat from the silicon oxynitride-containing composition. The resin substrate may be a single resin using one of the above resins, or a mixed resin blended from two or more types.

[0027] <Silicon oxynitride> The heat-dissipating resin composition contains silicon oxynitride (Si2N2O). The silicon oxynitride (Si2N2O) is the same as in the first embodiment of the present invention.

[0028] <Silicon-based compounds> The heat-dissipating resin composition preferably contains a silicon-based compound as an optional component, and the silicon-based compound is the same as in the first embodiment of the present invention.

[0029] (Particle size of silicon oxynitride and silicon-based compounds) The particle sizes of silicon oxynitride and silicon-based compounds are the same as those in the silicon oxynitride-containing composition of the first embodiment of the present invention.

[0030] <Additives> The heat-dissipating resin composition may contain additives exemplified as optional additives included in the silicon oxynitride-containing composition of the first embodiment of the present invention, as well as known resin additives. The content of the optional additives is preferably 0.01 to 1% by mass, more preferably 0.05 to 0.5% by mass, based on 100% by mass of the heat-dissipating resin composition.

[0031] (Silicon oxynitride content in heat-dissipating resin composition) The silicon oxynitride content in the heat-dissipating resin composition is 0.5 to 15.0% by mass, preferably 1.0 to 5.0% by mass, and more preferably 2.0 to 4.5% by mass, per 100% by mass of the heat-dissipating resin composition, taking into consideration the transparency and heat dissipation when producing a heat-dissipating resin film sheet. Within this usage range, the resulting film sheet can achieve both a transparent appearance and a good heat dissipation effect. On the other hand, when preparing and using a masterbatch of the heat-dissipating resin composition, the silicon oxynitride content in the heat-dissipating resin composition is usually 5% by mass or more and 33% by mass or less, from the viewpoint of dispersibility during kneading.

[0032] <Manufacturing method: Heat dissipating resin composition> The heat-dissipating resin composition of the present invention can be produced by mixing a silicon oxynitride-containing composition according to the first aspect of the present invention with a resin. Alternatively, the heat-dissipating resin composition may be produced by mixing silicon oxynitride, and optionally silicon-based compounds and additives, with a resin. The mixing method is not particularly limited as long as the silicon oxynitride-containing composition according to the first aspect of the present invention or silicon oxynitride, resin, and any additives can be uniformly mixed. Specific mixing methods include, for example, a melt-kneading method in which the powdery, granular, and / or slurry-like silicon oxynitride-containing composition, resin, and any additives are heated, melted, and kneaded with resin pellets or pulverized resin, or, if the silicon oxynitride-containing composition is in slurry form, a method in which the resin is added to the slurry-like silicon oxynitride-containing composition, heated, and dissolved or dispersed to obtain a slurry mixture of the heat-dissipating resin composition. Therefore, the heat-dissipating resin composition may include an embodiment comprising the silicon oxynitride-containing composition and resin according to the first embodiment of the present invention.

[0033] Next, we will describe the melt-mixing method as a method for producing the heat-dissipating resin composition. (Equipment used: Melt-mixing method) The equipment used for the melt-kneading method is not particularly limited as long as it is capable of carrying out the above method, but preferably a Banbury mixer, Plastmill, Brabender plastograph, unscrew extruder, or twin-screw extruder is used, and the heat-dissipating resin composition is obtained in a solid form, such as in lumps, threads, or pellets, using these machines. Alternatively, before melt-kneading, the silicon oxynitride-containing composition and the resin substrate may be mixed in a solid state beforehand using, for example, a Henschel mixer, ribbon blender, or blender, and then introduced into the machine as a homogeneous mixture.

[0034] (Mixing temperature: melt mixing method) In the melt-kneading method, the temperature of the kneading section (kneading section temperature; for example, mixer temperature in the case of a mixer, cylinder temperature in the case of an extruder) is set appropriately, as it depends on the glass transition point or melting point of the resin substrate used. The normal kneading temperature is 80 to 320°C, preferably 170 to 280°C. When the kneading temperature is within this range, the resin softens, melts, and mixes thoroughly without causing thermal decomposition of the resin. The kneading time is set appropriately, balancing the degree of mixing with the suppression of thermal decomposition. The normal kneading time is 0.1 to 30 minutes, preferably 2 to 15 minutes. When the kneading time is within this range, a well-mixed heat-dissipating resin composition is obtained without causing thermal decomposition of the resin.

[0035] [Heat-dissipating resin film or heat-dissipating resin sheet] Next, a heat-dissipating resin film or heat-dissipating resin sheet (also referred to in this application as a "heat-dissipating resin film sheet") will be described. The heat-dissipating resin film sheet refers to a self-supporting film or sheet containing the heat-dissipating resin composition. The heat-dissipating resin film sheet is preferably transparent, and here, transparency in this invention refers to the property that the haze measurement value of the resin film sheet, measured by a commercially available haze meter, is less than 100.

[0036] (Heat-dissipating resin film sheet: thickness) The thickness of the heat-dissipating resin film sheet is not particularly limited as long as moldability is maintained. However, from the viewpoint of heat dissipation performance, film sheet strength, and handling, the thickness of the heat-dissipating resin film sheet, as measured by a commercially available film thickness gauge, is preferably 0.01 mm to 3 mm, more preferably 0.05 mm to 3 mm, even more preferably 0.1 mm to 1 mm, particularly preferably 0.1 mm to 0.5 mm, and most preferably 0.1 mm to 0.25 mm. When the thickness of the heat-dissipating resin film sheet is within the above range, the strength is sufficient, and it does not become too thick and lose its flexibility.

[0037] (Heat-dissipating resin film sheet: Appearance) The appearance of the heat-dissipating resin film sheet is not particularly limited, as it is preferable that transparency is maintained, and the presence or absence of coloring is determined as appropriate according to the intended use. <Manufacturing method: Heat-dissipating resin film sheet> The heat-dissipating resin film sheet is prepared by processing and molding the heat-dissipating resin composition into a film or sheet. The preparation method is not particularly limited as long as it is a method for preparing a film sheet with a thickness that maintains the heat-dissipating resin film sheet as a self-supporting film. Specific preparation methods include, for example, preparing the heat-dissipating resin composition by heating and pressurizing it using a sheet molding machine such as a hot press, or preparing the heat-dissipating resin composition by melt-kneading it in a single-screw or twin-screw extruder, extruding it from a T-die, molding the extruded liquid into a sheet on a metal roll machine, and winding it up. Similarly, for the heat-dissipating resin composition in solution and slurry form, for example, the extruded liquid is extruded from a T-die, molded into a sheet on a heated metal roll machine while removing the solvent, and then wound up. The operating conditions and manufacturing conditions for the hot press and T-die used to obtain these sheets will vary depending on the intended use of the sheet to be manufactured, and will be set as appropriate.

[0038] [How to use heat-dissipating resin film or heat-dissipating resin sheet] The method of using the heat-dissipating resin film sheet is shown. The heat-dissipating resin film sheet obtained in the present invention is mainly designed for outdoor use. However, for example, it can be used indoors or for heat dissipation of electric and electronic devices, and it is not particularly limited. Also, the heat-dissipating resin film sheet can be used alone (single layer), or, for example, it can be laminated with other functional films or functional sheets to form a multilayer film or multilayer sheet for use, or it can be used as an adhesive film or adhesive sheet by providing an adhesive layer on one or both sides. Also, since the heat-dissipating resin film sheet is a self-supporting film, it can be used alone or in combination with a substrate. Here, examples of outdoor use applications include using the heat-dissipating resin film sheet as the roof sheet of dome-shaped sports facilities such as baseball fields and soccer fields, agricultural greenhouse sheets, fruit tree bags, car shades, etc. Examples of indoor use applications include, for example, a heat-dissipating film as a heat sink substitute for LED lamps, a heat-dissipating sheet pasted on a semiconductor housing part or a circuit board, etc.

Examples

[0039] Next, the present invention will be specifically described with reference to examples. Note that the raw materials, synthetic intermediates, amounts used, usage conditions (for example, usage time / season, usage environment temperature, usage time, usage location, etc.) and operations represented in the examples can be appropriately changed as long as they do not deviate from the technical idea of the present invention. Therefore, the scope of the present invention is not limited to the examples shown below. When the content of silicon oxynitride in the heat-dissipating resin composition is a powdery silicon oxynitride or a silicon oxynitride-containing composition, it is determined from the charged amount. When a slurry-like silicon oxynitride-containing composition is blended, since weighing errors are likely to occur, it is determined by TG / DTA analysis of the film sheet obtained from the heat-dissipating resin composition.

[0040] The measurements in the synthesis examples, reference examples, examples and comparative examples were carried out by the following methods. <XRD Analysis> X-ray source: Cu / Kα ray, measurement range: diffraction angle 2θ = 5 - 80°, scan speed: 2° / min, scan width: 0.02°.

[0041] <TG / DTA analysis> In accordance with ISO 11357-3, using a differential scanning calorimeter, the sample was heated up to 1000 °C, and the content of SiON in the combustion residue was determined.

[0042] (Synthesis Example 1: Raw material synthesis; powdered silicon oxynitride) Referring to JP-A-2021-34587 (Patent Document 4), using metallic silicon powder (Si) and silicon dioxide powder (SiO2) as starting materials, a powder mixture with a molar ratio of Si / SiO2 = 1.5 / 1 was mixed and fired at 1500 °C for 3 hours under a nitrogen flow (2 L / min) to obtain a块状 Si2N2O (hereinafter referred to as SiON). After cooling, the obtained块状 SiON was pulverized in a mortar to obtain powdered silicon oxynitride as a powder. The obtained powdered silicon oxynitride was subjected to XRD analysis. The results are shown in FIG. 1.

[0043] (Reference Example 1: Silicon oxynitride (SiON: product with a particle size of 45 μm or less)) 50 g of the powdered silicon oxynitride obtained in Synthesis Example 1 (a 50 g mixture of three kinds of products with a particle size of 5 mm or less, 7 mm or less, and 10 mm or less obtained by classifying the powdered silicon oxynitride obtained in Synthesis Example 1 using a sieve) was weighed into a plastic container, then added to a ball mill and pulverized using a pot mill turntable ANZ-52D (trade name, manufactured by Nippon Tokushu Toryo Co., Ltd.), and further classified using a sieve (45 μm) to obtain a silicon oxynitride-containing composition powder (SiON: product with a particle size of 45 μm or less) which is the target product.

[0044] (Example 1: Slurry-like silicon oxynitride-containing composition) 800 g of silicon oxynitride powder obtained in Synthesis Example 1 was added to an appropriate amount of ethanol, and the mixture was pulverized using a wet atomizing device: Starburst (product name: Sugino Machine Co., Ltd.) to obtain a silicon oxynitride-containing composition containing 10% by mass of silicon oxynitride powder in the composition and 100% by mass of silicon oxynitride powder in the solid content of the composition. The particle size distribution of the obtained slurry was measured using a laser diffraction scattering particle size distribution device (Malvern Mastersizer 3000), and the results were D50: 4.54 μm and D90: 10.9 μm.

[0045] (Example 2: Preparation of heat-dissipating resin composition (1): 2.2% by mass of Nylon-containing nylon resin composition) Under a nitrogen gas atmosphere, 6.00 g of nylon 6 (manufactured by Ube Industries) was added to a Laboplastmill KF15V mixer (product name, manufactured by Toyo Seiki Co., Ltd.) and dissolved at 230°C. A diluted solution (0.0216 g / 500 μl) of the 0.75 ml slurry of silicon oxynitride-containing composition obtained in Example 1 was added five times. The mixture was then kneaded for 10 minutes at a mixer temperature of 230°C and a rotation speed of 30 rpm to obtain the target heat-dissipating resin composition (1). The SiON content in the composition was determined in Example 3.

[0046] (Example 3: Manufacturing of heat-dissipating resin film sheet (1): 2.2% by mass Nylon-containing nylon resin film sheet) The heat-dissipating resin composition obtained in Example 2 was pressed using a hot press (manufactured by Tester Sangyo Co., Ltd.) at a temperature of 190°C and a pressure of 5 MPa for 3 minutes, followed by a pressure of 10 MPa for 3 minutes. After cooling, the resulting sheet was cut to obtain the target heat-dissipating resin film sheet (1) measuring 100 mm × 100 mm with a thickness of approximately 100 μm. TG / DTA analysis of the obtained heat-dissipating resin film sheet (1) revealed that the film sheet contained 2.2% by mass of SiON.

[0047] (Example 4: Preparation of heat-dissipating resin composition (2): 4.2% by mass Nylon-containing nylon resin composition) Except for adding a diluted solution (0.0216 g / 500 μl) of the 0.75 ml slurry-like silicon oxynitride-containing composition obtained in Example 1 10 times, nylon 6 was kneaded in the same manner as in Example 2 to obtain the target heat-dissipating resin composition (2). The SiON content in the composition was determined in Example 5.

[0048] (Example 5: Manufacturing of heat-dissipating resin film sheet (2): 4.2% by mass of Nylon-containing nylon resin) The same procedure as in Example 3 was followed, except that the heat-dissipating resin composition obtained in Example 4 was used, to obtain the target product, a heat-dissipating resin film sheet (2) measuring 100 mm × 100 mm with a thickness of approximately 100 μm. TG / DTA analysis of the obtained heat-dissipating resin film sheet (2) revealed that the film sheet contained 4.2% by mass of SiON.

[0049] (Example 6: Preparation of heat-dissipating resin composition (3): 2.2% by mass of polyethylene resin containing SiON) 0.132 g of silicon oxynitride obtained in Reference Example 1 and 5.98 g of polyethylene (LLDPE; manufactured by Ube Industries, Ltd.) were kneaded in a Laboplast Mill at a mixer temperature of 190°C and a rotation speed of 30 rpm for 10 minutes to obtain the target heat-dissipating resin composition (3). The heat-dissipating resin composition (3) contains 2.2% by mass of silicon oxynitride.

[0050] (Example 7: Manufacturing of heat-dissipating resin film sheet (3): 2.2% by mass polyethylene film sheet containing SiON) The heat-dissipating resin composition obtained in Example 6 was pressed using a hot press at a temperature of 190°C and a pressure of 5 MPa for 3 minutes, followed by a pressure of 10 MPa for 3 minutes. After cooling, the resulting sheet was cut to obtain the target heat-dissipating resin film sheet (3) measuring 100 mm × 100 mm with a thickness of approximately 100 μm. The IR spectrum of the obtained heat-dissipating resin film sheet (3) is shown in Figure 2.

[0051] (Comparative Example 1: Heat-dissipating resin film sheet (4): 2.1% by mass of Tempax-containing polyethylene resin) Commercially available Tempax glass (registered trademark) was crushed and classified using a 45 μm sieve to obtain Tempax glass powder (particle size: 45 μm or less): 0.1296 g (equivalent to 2.1% by mass) and polyethylene (LLDPE; manufactured by Ube Industries, Ltd.) 5.98 g were kneaded in a Laboplast mill at a mixer temperature of 190 °C and a rotation speed of 30 rpm for 10 minutes to obtain the target product, a heat-dissipating resin composition (4). The heat-dissipating resin composition (4) contains 2.1% by mass of the Tempax glass component. The obtained heat-dissipating resin composition (4) was processed in the same manner as described in Example 5 to obtain the target product, a heat-dissipating resin film sheet (4) measuring 100 mm × 100 mm with a thickness of approximately 100 μm.

[0052] (Example 8: Production of heat-dissipating resin composition masterbatch (5): 33% by mass polyethylene containing SiON) Using a Laboplast Mill to mix silicon oxynitride obtained in Reference Example 1 with polyethylene (HDPE; Hyzex 3300, manufactured by Mitsui Chemicals) in a mass ratio (silicon oxynitride:polyethylene = 15:30), approximately 300 g of the target heat-dissipating resin composition masterbatch (polyethylene containing 33% by mass of silicon dioxide) was obtained.

[0053] (Example 9: Manufacturing of heat-dissipating resin film sheet (5): 2.6% by mass polyethylene film sheet containing SiON) The mass of the heat-dissipating resin composition masterbatch obtained in Example 8 was crushed and sieved (20 mesh) to obtain finely ground material. Next, the obtained finely ground material and polyethylene (HDPE; HiZEX 3300, manufactured by Mitsui Chemicals) were kneaded using a Laboplast mill to achieve a mass ratio (silicon oxynitride:polyethylene = 3:97) (mixer temperature: 200°C, rotation speed: 60 rpm, 5 minutes). Subsequently, the kneaded material was extruded in sheet form from a T-die (width: 60 mm, lip thickness: 0.5 mm) via a twin-screw extruder (internal temperature: 240°C). The extruded kneaded material was wound into a sheet while being cooled on a metal roll (roll temperature: 90~95°C) to obtain the target product, a polyethylene film sheet containing 3 mass% SiON with a thickness of approximately 100 μm. TG / DTA analysis of the obtained heat-dissipating resin film sheet (5) revealed that the film sheet contained 2.6 mass% SiON.

[0054] (Measurement example: Evaluation of heat dissipation resin film sheet manufacturing: Heat dissipation temperature measurement) The heat-dissipating resin film sheets obtained in Examples 3, 5, 7, and Comparative Example 1 were evaluated using the outdoor evaluation apparatus shown in Figure 3. Specifically, as explained in Figure 3, the film sheet was fixed to the upper surface of the heat-dissipating evaluation cell 10 with fixing device A (window frame 3 cm square) or fixing device B (window frame 5 cm × 9 cm) 13, and the temperature of the space inside the cell was measured for one week. The temperature difference ΔT between the space temperature inside the cell 16 covered with the heat-dissipating resin film sheets obtained in Examples 3, 5, 7, and Comparative Example 1 and the space temperature inside the cell 18 covered with the silicon oxynitride-containing composition and the resin substrate film sheet without additives (control) is shown in Figures 4 to 6. The cell using fixing device A is designated as cell A, and the cell using fixing device B is designated as cell B. Furthermore, after the measurement, the appearance of the film sheets in Examples 3 and 5 was photographed, and haze measurement was performed using a haze meter: NDH7000SPII (product name, manufactured by Nippon Denshoku Industries Co., Ltd.). The comparative example was also evaluated in the same manner as in the examples, and the ΔT is shown in Figure 7. These results are summarized in Table 1.

[0055] [Table 1] *1: SiON: Silicon oxynitride, Content: Mass % of silicon oxynitride contained in the heat-dissipating resin film sheet. *2: Film thickness: μm. *3: Measured value by haze meter: %. Haze value of resin substrate film sheet (control: without silicon oxynitride-containing composition): 63.7. *4: Data not provided. *5: Spatial temperature difference: ΔT (°C) = [Temperature in the space with the heat-dissipating resin film sheet attached (Figure 2:16): °C] - [Temperature in the space with the resin substrate film sheet (control) attached (Figure 2:18): °C], *6: Using cell A (Figure 2:13), *7: Using cell B (Figure 2:14)

[0056] From Figures 4-6, the results from Examples 3 and 5 show that the heat-dissipating resin film sheets obtained from the heat-dissipating resin composition of the present invention, which contains the silicon oxynitride-containing composition of the present invention, exhibited a good cooling tendency (heat dissipation effect) that was generally proportional to the silicon oxynitride content. Furthermore, the heat dissipation effect was confirmed by comparing Example 7 with Comparative Example 1 in Figures 6 and 7. While the Tempax used in Comparative Example 1 showed a warming tendency at certain times, only a cooling tendency was observed in Example 7. Therefore, it was confirmed that the heat-dissipating resin composition of the present invention exhibits excellent heat dissipation properties. [Industrial applicability]

[0057] The silicon oxynitride-containing composition obtained in this invention can be used as a so-called heat dissipation filler, in addition to heat dissipation resin films or heat dissipation resin sheets, as well as as a compounding component in heat dissipation resin compositions used in, for example, heat dissipation paints and light-shielding paints. Furthermore, the heat dissipation resin composition containing silicon oxynitride can be expected to have good heat dissipation (cooling effect) as an outdoor material such as a heat dissipation film or heat dissipation sheet, such as a camping tent or an agricultural film. Thus, this invention makes a significant contribution to improving energy efficiency and can contribute to achieving SDGs (Sustainable Development Goals) Goal 7, among others. [Explanation of Symbols]

[0058] 10 Heat dissipation evaluation device 11. Rainproof cover (biaxially oriented polypropylene film) 12. Expanded polystyrene foam insulation 13. Sample Fixture A: 3cm square window frame or Sample Fixture B: 5cm x 9cm window frame 14 Heat-dissipating resin film sheet 15 Thermocouples 16. Cavity (top surface is a heat-dissipating resin film sheet) 17 Installation stand 18. Hollow (the top surface is a symmetrical film sheet)

Claims

1. A silicon oxynitride-containing composition comprising 50% by mass or more of silicon oxynitride in 100% by mass of the solid content of the silicon oxynitride-containing composition, Furthermore, it contains 0.5 to 15% by mass of silicon nitride and silicon dioxide. A silicon oxynitride-containing composition that does not contain resin.

2. The silicon oxynitride-containing composition according to claim 1, further comprising a liquid.

3. A silicon oxynitride-containing composition according to claim 1 or 2, used in the production of a heat-dissipating resin composition for forming a film or sheet.

4. The silicon oxynitride-containing composition according to any one of claims 1 to 3, wherein the 50% diameter (D50) of the silicon oxynitride is 100 μm or less.

5. The silicon oxynitride-containing composition according to any one of claims 1 to 4, wherein the silicon dioxide does not contain cristobalite.

6. A heat-dissipating resin composition comprising silicon oxynitride and a resin, wherein the heat-dissipating resin composition contains 0.5 to 15.0% by mass of silicon oxynitride in 100% by mass of the heat-dissipating resin composition, Furthermore, it contains silicon nitride and silicon dioxide, The resin has no absorption wavelength in the range of 8 to 13 μm, or its absorbance, as measured by infrared spectroscopy (IR) at absorption wavelengths in the range of 8 to 13 μm, is 0.2 or less. Heat dissipating resin composition.

7. The heat-dissipating resin composition according to claim 6, wherein the resin is at least one selected from the group consisting of polyolefins and polyamides.

8. The heat-dissipating resin composition according to claim 6 or 7, wherein the 50% diameter (D50) of the silicon oxynitride is 100 μm or less.

9. The heat-dissipating resin composition according to any one of claims 6 to 8, wherein the silicon dioxide does not contain cristobalite.

10. A heat-dissipating resin film or heat-dissipating resin sheet comprising the heat-dissipating resin composition according to any one of claims 6 to 9.

11. A heat-dissipating resin film or heat-dissipating resin sheet according to claim 10, having a thickness of 0.01 to 3 mm.

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