Flake-like substrate and resin composition

Abstract

Provided is a flake-like substrate having an average particle size of 0.1-11 μm and an average thickness of 0.1-1.0 μm, and satisfying D99≤35μm, D100≤45μm, 3<D90 / D10, and (D90×D99×D100) / D50≤3200, where D10, D50, D90, D99, and D100 are the particle size corresponding to a cumulative volume of 10%, 50%, 90%, 99%, and 100%, respectively, from the smaller particle size side in the particle size distribution.

Description

Technical Field

[0001] The present invention relates to a flaky substrate and a resin composition.

Background Art

[0002] In resin molded products, for the purpose of reducing warpage and deformation and / or improving mechanical strength, flaky substrates such as glass fibers, carbon fibers, glass beads, and flaky glass, mica, talc, etc. are generally known to be blended into the matrix resin as fillers.

[0003] For example, in Patent Document 1, there is proposed a flaky glass having an average particle size of 0.1 to 15 μm and an average thickness of 0.1 to 2 μm, and having a reduced particle size by limiting the particle size D99 corresponding to 99% of the volume accumulation from the smaller particle size side in the particle size distribution to 45 μm or less and the maximum particle size (D100) to 62 μm or less.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When the flaky glass of Patent Document 1 is used as a filler for reinforcing a resin molded product, the impact resistance of the obtained resin molded product can be improved. However, according to the study by the present inventors, even if D99 is limited to 45 μm or less and D100 is limited to 62 μm or less, there is still room for improvement in the impact resistance of the resin molded product using the flaky substrate.

[0006] One object of the present invention is to improve a flaky base material suitable for use as a filler for reinforcing a resin molded product. Another object of the present invention is to improve the impact resistance of a resin molded product reinforced with the flaky base material.

Means for Solving the Problems

[0007] According to one aspect of the present invention, a flaky base material having an average particle diameter of 0.1 to 11 μm and an average thickness of 0.1 to 1.0 μm, in the particle size distribution of the flaky base material, when the particle diameter corresponding to a volume accumulation of 10% from the smaller particle diameter side is defined as D10, the particle diameter corresponding to a volume accumulation of 50% from the smaller particle diameter side is defined as D50, the particle diameter corresponding to a volume accumulation of 90% from the smaller particle diameter side is defined as D90, the particle diameter corresponding to a volume accumulation of 99% from the smaller particle diameter side is defined as D99, and the particle diameter corresponding to a volume accumulation of 100% from the smaller particle diameter side is defined as D100, D99 ≦ 35 μm, D100 ≦ 45 μm, 3 < D90 / D10, and (D90 × D99 × D100) / D50 ≦ 3200, is satisfied, a flaky base material is provided. However, (D90 × D99 × D100) / D50 is calculated with the units of D50, D90, D99 and D100 being μm.

[0008] According to another aspect of the present invention, a resin composition containing a flaky base material and a matrix resin, the flaky base material contained in the resin composition, has an average particle diameter of 0.1 to 11 μm and an average thickness of 0.1 to 1.0 μm, In the particle size distribution, when the particle diameter corresponding to a volume accumulation of 10% from the smaller particle diameter side is defined as D10, the particle diameter corresponding to a volume accumulation of 50% from the smaller particle diameter side is defined as D50, the particle diameter corresponding to a volume accumulation of 90% from the smaller particle diameter side is defined as D90, the particle diameter corresponding to a volume accumulation of 99% from the smaller particle diameter side is defined as D99, and the particle diameter corresponding to a volume accumulation of 100% from the smaller particle diameter side is defined as D100, D99 ≤ 35 μm, D100 ≤ 45 μm, 3 < D90 / D10, and (D90 × D99 × D100) / D50 ≤ 3200, is satisfied, A resin composition is provided. However, (D90 × D99 × D100) / D50 is calculated with the units of D50, D90, D99, and D100 being μm.

Advantages of the Invention

[0009] According to the present invention, a flaky substrate suitable for use as a filler for reinforcing a resin molded product is provided, and furthermore, the impact resistance of the resin molded product reinforced with the flaky substrate can be improved.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the flaky substrate and the resin composition of the present invention will be specifically described, but the following description is not intended to limit the present invention to specific embodiments.

[0012] [Background of the Invention] In accordance with the teachings of Patent Document 1, it has been found that even if the upper limits of D99 and D100 are restricted, the impact strength of the resin molded product may not be sufficiently increased. When further examining this factor, it was confirmed that, together with the D values (D99 and D100) in the region where the volume accumulation is 99% or more, the D values in the region near D90 adjacent to this region also affect the impact resistance. Moreover, surprisingly, for D50, if the parameters (D90 to D100) to be restricted are restricted to the same extent, relatively large values may be suitable for improving the impact strength. Considering these, it is desirable that the value calculated by (D90 × D99 × D100) / D50 be restricted to a predetermined value or less. However, it is not necessary to extremely restrict the spread of the particle size distribution in order to keep this value low. The unnecessary restriction of the particle size distribution is to significantly reduce the production efficiency of the flaky substrate. From this viewpoint, D90 / D10 may be a predetermined value or more. Considering the above, the present invention has been completed, and its embodiments will be described below.

[0013] [Flaky substrate] The flaky substrate of the present embodiment has an average particle diameter of 0.1 to 11 μm and an average thickness of 0.1 to 1.0 μm. Further, in the particle size distribution of the flaky substrate of the present embodiment, the particle diameter corresponding to a volume accumulation of 10% from the smaller particle diameter side is defined as D10, the particle diameter corresponding to a volume accumulation of 50% from the smaller particle diameter side is defined as D50, the particle diameter corresponding to a volume accumulation of 90% from the smaller particle diameter side is defined as D90, the particle diameter corresponding to a volume accumulation of 99% from the smaller particle diameter side is defined as D99, and the particle diameter corresponding to a volume accumulation of 100% from the smaller particle diameter side is defined as D100. When defined in this way, D99 ≤ 35 μm, D100 ≤ 45 μm, 3 < D90 / D10, and (D90 × D99 × D100) / D50 ≤ 3200 are satisfied. However, the last formula is applied with the units of D50, D90, D99 and D100 being μm. D10, D50, D90, D99 and D100 can be determined based on volume standards using the laser diffraction / scattering method.

[0014] When the flaky base material having the above characteristics is used as a filler for reinforcing a resin molded product, it is suitable for improving the impact resistance of the obtained resin molded product. Furthermore, the appearance and surface smoothness of the obtained resin molded product can be improved.

[0015] The flaky base material of the present embodiment may be an inorganic base material formed of an inorganic material or an organic base material formed of an organic material. Examples of the inorganic base material include a base material formed of carbon such as glass, mica, talc, wollastonite, kaolin, calcium carbonate, montmorillonite, silica, clay, bentonite, hydrotalcite, or graphite. Examples of the organic base material include a base material formed of aramid, polyamide, polyester, polyethylene, polypropylene, acrylic, or rayon. Also, as another organic base material, a base material obtained by forming cotton, hemp, or silk into flakes can be used.

[0016] The flaky base material of the present embodiment may be composed of at least one selected from the group consisting of glass, mica, and talc. The flaky base material of the present embodiment may be flaky glass.

[0017] The average particle size of the flaky base material of the present embodiment is within the range of 0.1 to 11 μm as described above. The average particle size may be 0.5 μm or more, 1.0 μm or more, 2.2 μm or more, and further 2.4 μm or more. The average particle size may be, for example, within the range of 2.4 to 11 μm. The average particle size may be 5 μm or less. In this specification, the average particle size of the flaky base material is the particle size (D50) corresponding to 50% of the volume accumulation from the smaller particle size side in the particle size distribution of the flaky base material measured based on the laser diffraction / scattering method. According to the present embodiment, a flaky base material suitable for improving the impact strength of a resin molded product can be obtained without significantly restricting the entire particle size and reducing the average particle size (D50). A flaky base material having a large average particle size is generally advantageous in that the degree of scattering during its handling is suppressed.

[0018] As described above, the average thickness of the flaky base material in this embodiment is within the range of 0.1 to 1.0 μm. The average thickness may be 0.2 μm or more, and further may be 0.3 μm or more. The average thickness may be 0.9 μm or less, 0.8 μm or less, and further may be 0.7 μm or less. In this specification, the average thickness of the flaky base material can be calculated, for example, as a value obtained by measuring the thickness of 100 or more flaky base materials from the flaky base material using a scanning electron microscope (SEM) and dividing the total thickness by the number of measured pieces.

[0019] The width of the particle size distribution of the flaky base material can be indicated by taking D90 / D10 as an index. The larger the value of D90 / D10, the wider the width of the particle size distribution, and the smaller the value of D90 / D10, the narrower the width of the particle size distribution. (D90 × D99 × D100) / D50 is an index indicating the content rate of coarse particles in the particle size distribution. The larger the value of (D90 × D99 × D100) / D50, the higher the content rate of coarse particles, and the smaller the value of (D90 × D99 × D100) / D50, the lower the content rate of coarse particles.

[0020] Here, for example, the flaky base material used as a pearlescent pigment generally preferably has a narrow width of the particle size distribution (that is, a low content rate of fine particles and coarse particles). For example, Patent No. 4652445 discloses flaky particles (flaky glass) applied to a pearlescent pigment, and the flaky particles having a D90 / D10 value of 2.0 or more and 3.0 or less. On the other hand, the flaky base material used as a filler for reinforcing a resin molded product does not need to have a narrow width of the particle size distribution. In the flaky base material of this embodiment, the fact that (D90 × D99 × D100) / D50 ≤ 3200 and 3 < D90 / D10 are simultaneously satisfied means that while the content rate of coarse particles is greatly reduced, the content rate of fine particles is not strictly controlled. By allowing the width of the particle size distribution to be wide, the labor required for classification is reduced. In particular, the operation of strictly limiting the content rate of fine powder greatly reduces the production efficiency, so the advantage that this operation becomes unnecessary is great. In addition, when there is a certain amount of fine powder, an effect of improving the filling property and fluidity when injecting the resin composition can also be expected compared to the case of strictly limiting the content rate of fine powder.

[0021] The (D90×D99×D100) / D50 of the flake-shaped substrate in this embodiment is preferably 2800 or less ((D90×D99×D100) / D50≦2800), and particularly 2700 or less. The lower limit of (D90×D99×D100) / D50 is preferably 300 or more (300≦D90×D99×D100). The lower limit particle size at which the flake-shaped substrate converges is determined by the grinding method and conditions, but a lower limit of (D90×D99×D100) / D50 of 300 or more means that the grinding is stopped at an appropriate level that is efficient for manufacturing, in other words, the coarse particle content is not reduced too much. As a result, the effort required to excessively reduce the coarse particle content during grinding, i.e., the grinding time is reduced, and manufacturing efficiency is improved. Furthermore, the presence of a small amount of coarse particles reduces the scattering of the flake-like substrate compared to the case where there are almost no coarse particles, thus improving handling. The lower limit of (D90×D99×D100) / D50 for the flake-like substrate in this embodiment is 700 or more (700≦). ( (D90×D99×D100) / D50) That's fine.

[0022] The upper limit of D90 / D10 for the flake-like substrate in this embodiment is not particularly limited, but for example, it is 13 or less (D90 / D10 ≤ 13). The upper limit of D90 / D10 may also be 11 or less (D90 / D10 ≤ 11).

[0023] The D10 of the flake substrate in this embodiment may be 10 μm or less (D10 ≤ 10 μm), and moreover, 6.0 μm or less (D10 ≤ 6.0 μm). Preferably, D10 is 2.0 μm or less (D10 ≤ 2.0 μm). The lower limit of D10 is not particularly limited, but for example, it is 0.5 μm or more (0.5 μm ≤ D10).

[0024] The appropriate value for D50 of the flake-shaped substrate in this embodiment is as described above in terms of average particle size.

[0025] The D90 of the flake-like substrate in this embodiment may be 25 μm or less (D90 ≤ 25 μm), and may even be 20 μm or less (D90 ≤ 20 μm). Preferably, D90 is 11 μm or less (D90 ≤ 11 μm). The lower limit of D90 is not particularly limited, but for example, it is 5.0 μm or more (5.0 μm ≤ D90).

[0026] The D99 of the flake-like substrate in this embodiment is preferably 21 μm or less (D99 ≤ 21 μm). The lower limit of D99 is not particularly limited, but for example, it is 10 μm or more (10 μm ≤ D99).

[0027] In this embodiment, the D100 of the flake-like substrate is preferably 32 μm or less (D100 ≤ 32 μm). The lower limit of D100 is not particularly limited, but for example, it is 18 μm or more (18 μm ≤ D100).

[0028] The D10, D50, D90, D99, and D100 values ​​in the particle size distribution of the flake-shaped substrate in this embodiment were measured after being dispersed in water.

[0029] Flake-shaped glass can be suitably used as the flake-shaped substrate in this embodiment. The composition of the flake-shaped glass can be any composition of glass that is generally known. Specifically, glass with low alkali metal oxide content, such as E-glass, for example, glass with a total content of Na2O and K2O of 2% or less by mass, can be suitably used. Typical compositions of E-glass are shown below. The units for the compositions below are in mass%.

[0030] 52 ≤ SiO2 ≤ 56 12 ≤ Al2O3 ≤ 16 16 ≤ CaO ≤ 25 0 ≤ MgO ≤ 6 0 ≤ (Na2O + K2O) ≤ 2 (preferably, 0 ≤ (Na2O + K2O) ≤ 0.8) 5 ≤ B2O3 ≤ 13 0 ≤ F2 ≤ 0.5

[0031] Also, as another type of glass with low alkali metal oxide content, expressed in mass percent, 59 ≤ SiO2 ≤ 65 8 ≤ Al2O3 ≤ 15 47 ≤ (SiO2 - Al2O3) ≤ 57 1 ≤ MgO ≤ 5 20 ≤ CaO ≤ 30 0 < (Li2O + Na2O + K2O) < 2 0 ≤ TiO2 ≤ 5 A glass composition can be used that contains the components of and substantially does not contain B2O3, F, ZnO, BaO, SrO, and ZrO2. This glass composition is disclosed by the applicant in International Publication 2006 / 068255. Hereinafter, glass having this glass composition will be referred to as "TA-1 glass". "Substantially does not contain" means that these components are intentionally omitted, except in cases where they are inevitably mixed in by industrial raw materials, for example. Specifically, this means that the content of each of B2O3, F, ZnO, BaO, SrO, and ZrO2 is less than 0.1% by mass (preferably less than 0.05% by mass, more preferably less than 0.03% by mass).

[0032] Furthermore, as another type of glass, expressed in mass%, 60 ≤ SiO2 ≤ 75 5 <Al2O3≦15 3 ≤ CaO ≤ 20 6 ≤ Na₂O ≤ 20 9 ≤ (Li2O + Na2O + K2O) ≤ 20 The following glass composition can also be used. This glass composition is disclosed by the applicant in International Publication No. 2010 / 024283. Hereinafter, glass having this glass composition will be referred to as "TA-2 glass".

[0033] The composition of the flake glass is not limited to the glass compositions of E glass, TA-1 glass, and TA-2 glass described above. For example, the glass compositions of C glass, A glass, ECR glass, and S glass can also be used. The glass compositions of low-dielectric glass disclosed by the applicant (see, for example, Japanese Patent No. 6505950, Japanese Patent No. 6775159, International Publication No. 2020 / 255396, International Publication No. 2020 / 256142, International Publication No. 2020 / 256143, and International Publication No. 2021 / 049581) can also be used.

[0034] The flake-shaped glass of this embodiment can be produced, for example, by the so-called blow method disclosed in Japanese Patent Publication No. 41-17148 and Japanese Patent Publication No. 45-3541, or by the so-called rotary method disclosed in Japanese Patent Publication No. 59-21533 and Japanese Patent Publication No. 2-503669.

[0035] In the blow glass method, the glass manufacturing apparatus shown in Figure 1 can be used. This glass manufacturing apparatus is equipped with a refractory kiln tank 12, a blow nozzle 15, and a pressure roll 17. The glass substrate 11, melted in the refractory kiln tank 12 (melting tank), is inflated into a balloon shape by gas supplied to the blow nozzle 15, forming a hollow glass film 16. The hollow glass film 16 is crushed by the pressure roll 17 to obtain flake glass 1. The thickness of the flake glass 1 can be controlled by adjusting the tensile speed of the hollow glass film 16, the flow rate of gas supplied from the blow nozzle 15, etc.

[0036] In the rotary method, the glass manufacturing apparatus shown in Figure 2 can be used. This glass manufacturing apparatus comprises a pipe 21, a rotating cup 22, a set of annular plates 23, and an annular cyclone-type collector 24. The molten glass substrate 11 is poured from the pipe 21 into the rotating cup 22, flows out radially from the upper edge of the rotating cup 22 by centrifugal force, is sucked in by an airflow through the annular plates 23, and introduced into the annular cyclone-type collector 24. As it passes through the annular plates 23, the glass cools and solidifies in the form of a thin film, and is further crushed into minute pieces to obtain flake-like glass 1. The thickness of the flake-like glass 1 can be controlled by adjusting the spacing of the annular plates 23, the speed of the airflow, etc.

[0037] The flake-shaped substrate of this embodiment enables the creation of a resin molded product with improved impact resistance, even if at least a portion of its surface is not covered with a surface treatment agent. to do It is possible.

[0038] However, the flake-shaped substrate of this embodiment may have at least a portion of its surface covered with a surface treatment agent. The surface treatment agent includes, for example, at least one selected from the group consisting of a binder component and a silane coupling agent.

[0039] The binder component included in the surface treatment agent is not particularly limited, and known binder components used for surface treatment of flake-shaped substrates can be used as appropriate. For example, examples of organic binder components include methylcellulose, carboxymethylcellulose, starch, carboxymethyl starch, hydroxyethylcellulose, hydroxypropylcellulose, polyvinyl alcohol, acrylic resin, epoxy resin, epoxy-modified polyolefin resin, phenolic resin, vinyl acetate, and urethane resin. Examples of inorganic binder components include water glass, colloidal silica, and colloidal alumina.

[0040] For example, when an epoxy-modified polyolefin resin is used as a binder component, preferred embodiments of the epoxy-modified polyolefin resin include polyolefin-glycidyl methacrylate copolymers, polyolefin-allyl glycidyl ether copolymers, and / or copolymers in which polyolefin is grafted with glycidyl methacrylate or allyl glycidyl ether in conjunction with an organic peroxide. In particular, ethylene-glycidyl methacrylate copolymers (especially ethylene-glycidyl methacrylate graft copolymers) having ethylene and glycidyl methacrylate as essential components are preferably used. However, it is not limited to these, and other copolymers such as ethylene-vinyl acetate-glycidyl methacrylate copolymer, ethylene-methyl acrylate-glycidyl methacrylate copolymer, ethylene-ethyl acrylate-glycidyl methacrylate copolymer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, ethylene-acrylic acid-acrylic acid-glycidyl methacrylate copolymer, ethylene-methacrylate-glycidyl methacrylate copolymer, ethylene-methacrylic acid-methacrylic acid copolymer-glycidyl methacrylate copolymer, ethylene-polypropylene copolymer-glycidyl methacrylate graft copolymer, ethylene-vinyl acetate copolymer-glycidyl methacrylate graft copolymer, and even polypropylene-glycidyl methacrylate copolymer and polypropylene-glycidyl methacrylate graft copolymer can also be used.

[0041] Furthermore, when a resin having a glycidyl group, so-called epoxy resin, is used as a binder component, examples of epoxy resins include bisphenol A type epoxy resin, phenol novolac type epoxy resin, O-cresol novolac type epoxy resin, bisphenol F type epoxy resin, biphenyl type epoxy resin, alicyclic epoxy resin, and hydrogenated bisphenol A type epoxy resin. Epoxy resins may be used individually or in combination of multiple types.

[0042] Examples of silane coupling agents include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, vinyltriethoxysilane, and γ-methacryloxypropyltrimethoxysilane. Among these, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, and γ-ureidopropyltriethoxysilane are preferably used. In addition to silane coupling agents, titanium-based coupling agents, aluminum-based coupling agents, zirconia-based coupling agents, etc., can also be used.

[0043] The surface treatment agent may contain other components as needed, in addition to the binder component and silane coupling agent described above. The surface treatment agent may further contain a crosslinking agent.

[0044] In addition to the above components, the surface treatment agent may further contain other components as needed, such as urethane resin, surfactants and / or defoamers.

[0045] The method for coating the surface of the flake-shaped substrate with a surface treatment agent is not particularly limited, and known methods can be used. For example, by adding a solution of the surface treatment agent to the flake-shaped substrate, stirring, and drying, a material can be formed in which at least a portion of the surface of the flake-shaped substrate is coated with the surface treatment agent. The specific methods for adding the solution of the surface treatment agent, stirring, and drying are not particularly limited, but examples are described below.

[0046] For example, in a mixer such as a rotary disc mixer or a Henschel mixer equipped with rotary blades in a mixing container, a predetermined amount of binder is added by spraying or the like while the flake-shaped substrate is flowing, and then mixed and stirred. Next, the flake-shaped substrate is dried while being stirred in the mixer, or the flake-shaped substrate is removed from the mixer and dried. By this method, a flake-shaped substrate coated with a surface treatment agent can be obtained.

[0047] As another example, flake-shaped substrates can also be produced using a rolling granulation method as described in Japanese Patent Publication No. 2-124732. That is, flake-shaped substrates may be placed in a horizontal vibrating granulator equipped with stirring blades, and a solution of a surface treatment agent may be sprayed onto them for granulation.

[0048] In addition to the methods mentioned above, flake-shaped substrates can also be produced by applying known methods generally known as agitation granulation, fluidized bed granulation, jet granulation, and rotary granulation.

[0049] The drying process is carried out, for example, by heating the flake-shaped substrate to a temperature above the boiling point of the solvent used in the surface treatment solution and drying it until the solvent evaporates.

[0050] The proportion of surface treatment agent in the flake-shaped substrate can be controlled by adjusting the concentration of the surface treatment agent in the surface treatment agent solution that is added or sprayed. In other words, by adding or spraying a predetermined amount of surface treatment agent solution to a predetermined amount of flake-shaped substrate so that the surface treatment agent is present in a predetermined amount, a flake-shaped substrate can be produced in which the proportion of the coating film made of surface treatment agent is a predetermined value.

[0051] In the flaky base material of the present embodiment, the content ratio of the coating film made of the surface treatment agent is, for example, 0.05 to 2% by mass, preferably 0.2 to 1.5% by mass, and more preferably 0.3 to 1% by mass. When the content ratio of the coating film is 0.05% by mass or more, the flaky base material can be sufficiently coated with the surface treatment agent, so that the occurrence of strength reduction of the resin molded product due to insufficient coating is suppressed. When the content ratio of the coating film is 2% by mass or less, the generation of problems such as gas generation during extrusion molding, causing mold contamination, or discoloration of the resin molded product is suppressed. Further, when the content ratio of the coating film is 2% by mass or less, the bonding force between the flaky base materials becomes too strong, and when the kneading of the resin molding is insufficient, the flaky base materials remain in the resin molded product as aggregates, which also hardly causes a decrease in the strength of the resin molded product. Also, when the content ratio of the coating film is 2% by mass or less, the components of the excessive coating film do not conversely inhibit the adhesion between the base material and the matrix resin, and good molded product characteristics can be obtained.

[0052] [Resin composition] Next, the resin composition of the present embodiment will be described. The resin composition of the present embodiment includes the flaky base material of the above-described present embodiment and a matrix resin. The flaky base material included in the resin composition of the present embodiment has an average particle diameter of 0.1 to 11 μm, an average thickness of 0.1 to 1.0 μm, satisfies D99 ≤ 35 μm, D100 ≤ 45 μm, 3 < D90 / D10, and (D90 × D99 × D100) / D50 ≤ 3200. By including the flaky base material of the present embodiment having the above characteristics as a filler, a resin molded product with improved impact resistance can be obtained. Further, by including the flaky base material of the present embodiment having the above characteristics as a filler, the appearance and surface smoothness of the obtained resin molded product can also be improved.

[0053] The values ​​of D10, D50, D90, D99, and D100 in the particle size distribution of the flake-like substrate contained in the resin composition of this embodiment satisfy the same numerical range as the values ​​of D10, D50, D90, D99, and D100 in the particle size distribution of the flake-like substrate of this embodiment described above. However, the particle size distribution of the flake-like substrate may be affected by the influence of dispersion into the resin composition, specifically by extrusion molding to obtain the resin composition containing the flake-like substrate and / or injection molding to mold the resin composition and obtain a resin molded product. In other words, the particle size distribution of the flake-like substrate in the resin composition is not necessarily the same as the particle size distribution of the flake-like substrate before dispersion into the resin composition. However, from the viewpoint of further improving impact strength, it is desirable that the particle size distribution of the flake-like substrate in the resin composition also satisfies the conditions described above for the flake-like substrate.

[0054] For example, the upper limit of the flake-like substrate contained in the resin composition of this embodiment may be 2800 ((D90 × D99 × D100) / D50 ≤ 2800). Similarly, the flake-like substrate contained in the resin composition may have a particle size distribution such that 300 ≤ (D90 × D99 × D100) / D50, and furthermore, D90 / D10 ≤ 13.

[0055] The D10, D50, D90, D99, and D100 values ​​in the particle size distribution of the flake-like substrate contained in the resin composition of this embodiment were measured by heating the resin composition in an atmosphere of 625°C, removing components other than the flake-like substrate, and then dispersing the extracted flake-like substrate in water.

[0056] The matrix resin may be, for example, a thermoplastic resin. The thermoplastic resin may be at least one selected from the group consisting of polypropylene, polyethylene, polybutylene terephthalate, polyethylene terephthalate, polycarbonate, polystyrene-based resin, styrene-acrylonitrile copolymer resin, polyacrylate, styrene-butadiene-acrylonitrile copolymer resin, polyarylene sulfide, polyphenylene sulfide, polyacetal, polyamide, polyamide-imide, liquid crystal polymer, polyetheretherketone, and polyetherimide. The flake-shaped substrate of this embodiment can achieve a high reinforcing effect on resin molded articles, especially when polyolefin is used as the matrix resin, and can achieve an even higher effect when polypropylene is used among polyolefins. Furthermore, the flake-shaped substrate of this embodiment can also achieve a high reinforcing effect on resin molded articles when polybutylene terephthalate or polycarbonate is used as the matrix resin.

[0057] The content of the flake-like substrate in the resin composition is preferably 3 to 70% by mass. A content of 3% by mass or more allows the flake-like substrate to fully exhibit its function as a reinforcing material. On the other hand, a content of 70% by mass or less allows the flake-like substrate to be uniformly dispersed in the resin composition. To further reduce the molding shrinkage rate, a content of 10% by mass or more and 50% by mass or less of the flake-like substrate is more preferable.

[0058] The resin composition may contain other components besides the matrix resin and flake-like substrate. Examples of other components include fillers such as carbon black and thermoplastic elastomers. Thermoplastic elastomers include olefin-based elastomers, styrene-based elastomers, and hydrogenated polymer-based elastomers. Examples of olefin-based elastomers include ethylene-α-olefin copolymer elastomers (ethylene-propylene copolymer elastomer (EPR), ethylene-butene copolymer elastomer (EBR), ethylene-hexene copolymer elastomer (EHR), ethylene-octene copolymer elatomer (EOR), etc.) and ethylene-α-olefin-diene terpolymer elastomers (ethylene-propylene-ethylidene norbornene copolymer, ethylene-propylene-butadiene copolymer, ethylene-propylene-isoprene copolymer, etc.). Two or more thermoplastic elastomers may be used in combination.

[0059] Resin molded articles produced using the resin composition of this embodiment can achieve improved impact resistance due to the reinforcing effect of the flake-like substrate. Furthermore, improved appearance and surface smoothness can also be obtained. [Examples]

[0060] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples. In the following examples, flake-shaped glass was used as the flake-shaped substrate.

[0061] [Flake-shaped glass] The shaping, crushing, classification to adjust the particle size distribution, and surface treatment of the flake-shaped glass were carried out by the methods described below.

[0062] <Molding> Using E glass, TA-1 glass, and TA-2 glass having the compositions shown in Tables 1A, 1B, and 1C, flake-shaped glass 1 to 3 were prepared by the blowing method described with reference to Figure 1. Specifically, the glass was heated to over 1200°C.melt Place each glass into the disintegration tank. melt The process was completed by blowing air through a nozzle to create a thin layer of glass, which was then continuously drawn out using a roller. The amount of air blown in and the roller rotation speed were adjusted to achieve the target thickness, yielding flake-shaped glass 1-3.

[0063] [Table 1A]

[0064] [Table 1B]

[0065] [Table 1C]

[0066] Table 2 shows the average thickness and average particle size (D50) of flake glass 1-3. The average thickness of the flake glass was calculated by measuring the thickness of 100 flake glass pieces using a SEM, dividing the total thickness by the number of pieces measured, and rounding the result to two decimal places. The D50 of flake glass 1-3 was measured using a laser diffraction particle size distribution analyzer (Microtrac-Bell, model: MT3300EX, measurement mode: HRA) with each flake glass piece dispersed in water.

[0067] <Crushing> The flake-shaped glass samples 1-3 were crushed using a ball mill to obtain flake-shaped glass samples a-f.

[0068] The average particle size (D50) of flake-shaped glass a to f is shown in Table 2. Since the flake-shaped glass does not break in the thickness direction, i.e., the perpendicular direction, there was no difference in the average thickness of the glass before and after crushing. The D50 of flake-shaped glass a to f was measured using the same method as for flake-shaped glass 1 to 3.

[0069] Ball mills that can be used include rolling ball mills (pot mills, tube mills, conical mills, etc.), vibratory ball mills (circular vibration type vibratory mills, orbital vibration type vibratory mills, centrifugal mills, etc.), and planetary mills.

[0070] In this embodiment, grinding was performed using a ball mill, but the grinding method is not limited to this, and grinding may be performed by other grinding methods, whether wet or dry. For example, an impact crusher, gyratory crusher, cone crusher, jaw crusher, roll crusher, cutter mill, self-grinding mill, stamp mill, stone mill, smelting mill, ring mill, roller mill, jet mill, hammer mill, pin mill, rotary mill, vibratory mill, planetary mill, attritor, or bead mill can be used individually. These methods may be used in combination as appropriate.

[0071] <Classification> Flake-like glass samples a to f were classified to obtain flake-like glass samples A to M. Specifically, flake-like glass samples A to M were obtained by sieving classification. Here, the reduction in the total mass of flake-like glass due to classification relative to the total mass of flake-like glass before classification is defined as the cut rate. A larger cut rate generally leads to a lower content of coarse particles (content of flake-like glass with larger particle sizes), so a larger cut rate is desirable. The cut rate is at least 5%, preferably 10%, more preferably 15%, and even more preferably 30%. However, if the cut rate is too high, the accuracy of the classification decreases, and the expected effect may not be obtained. Also, if the cut rate is too high, the yield decreases, leading to an increase in manufacturing costs. Therefore, it is desirable for the cut rate to be in the range of 15 to 45%.

[0072] The sieving and classification process may be carried out in multiple stages, rather than just once. In this example, the process started with a coarse sieve and the size of the sieve mesh was gradually reduced until the target cut rate was achieved.

[0073] For sieving and classification, for example, a dry vibrating sieve can be used. For example, by using a sieve with a mesh size of a predetermined size or larger to remove particularly large particles (e.g., D100 and D99), and then using a sieve with a mesh size of a predetermined size or smaller to further remove the next largest particles (e.g., D90), the content of coarse particles can be reduced, thereby obtaining flake-like glass having the particle size distribution of this embodiment. The mesh size of the sieve used here should be appropriately selected according to the particle size of the particles before sieving, the D50, D90, D99, D100, or D90 / D10 values ​​of the flake-like glass to be obtained, etc. Furthermore, the removed coarse particles can be reused by re-crushing and re-classifying. In this way, the final yield can be improved and costs can be reduced.

[0074] In this embodiment, a sieve was used classification Although the above was performed, the classification method is not limited to this. The target cut rate may be achieved by other classification methods, whether wet or dry. For example, in gravity field classification, horizontal flow and vertical upward flow (wet, air-tube type, fluidized bed type, multi-stage bend type) can be used. Inertial force field classification can be linear, curved (impactor type), and inclined (louver type, Coanda effect type) can be used. In centrifugal force field classification can be natural vortex type and forced vortex type.

[0075] The cut ratio and average particle size (D50) for the classification of flake-shaped glasses A to M are shown in Table 2. The D50 for flake-shaped glasses A to M was measured using the same method as for flake-shaped glasses 1 to 3.

[0076] <Surface treatment> For surface treatment, either surface treatment P or Q was adopted.

[0077] (Surface treatment P) 5 kg of flake glass was placed in a Henschel mixer and mixed and stirred for 15 minutes while adding the surface treatment solution by spray. The surface treatment solution was prepared using water as the solvent, with an emulsion of ethylene-glycidyl methacrylate copolymer as the binder component and a hydrolyzed solution of γ-aminopropyltriethoxysilane as the silane coupling agent. The undried flake glass was then removed from the mixer and dried in a dryer at 125°C for 8 hours to obtain flake glass in which at least a portion of the surface was covered with the surface treatment agent. The calculated proportion of the binder component in the dried flake glass was 50% by mass (containing approximately 10% surfactant derived from the emulsion), and the proportion of the silane coupling agent was 50% by mass.

[0078] (Surface treatment Q) Flake-like glass was obtained by the same method as surface treatment P, except that the binder component was a bisphenol A type epoxy resin emulsion and the silane coupling agent was 3-glycidoxypropyltrimethoxysilane. The calculated proportion of the binder component in the dried flake-like glass was 85% by mass (containing about 10% emulsion-derived surfactant in the 85% by mass), and the proportion of the silane coupling agent was 15% by mass.

[0079] <Calculation of surface treatment agent adhesion rate> The adhesion rate of the surface treatment agent was evaluated by the ignition loss method. In this embodiment, the adhesion rate of the surface treatment agent refers to the proportion of the coating film consisting of the surface treatment agent on the flake-shaped glass. Specifically, an appropriate amount of flake-shaped glass was dried at 110°C, then heated in an atmosphere of 625°C to remove the surface treatment agent from the surface of the flake-shaped glass, and the adhesion rate of the surface treatment agent on the flake-shaped glass was calculated from the difference between the mass of the flake-shaped glass before heating and the mass of the flake-shaped glass after heating.

[0080] [Table 2]

[0081] [Examples 1-4, Comparative Examples 1-12] The flake-like glass of Examples 1-4 and Comparative Examples 1-12 is indicated by alphabetical symbols in the flake-like glass column of Tables 3A-3C. Symbols A-M correspond to flake-like glass A-M in Table 2. Symbols a-f correspond to flake-like glass a-f in Table 2. Symbol 1 corresponds to flake-like glass 1 in Table 2. The same applies to the examples and comparative examples described later. Flake-like glass H and I were obtained by classifying flake-like glass 1 without crushing it. No surface treatment was applied to the flake-like glass of Examples 1-4 and Comparative Examples 1-12.

[0082] The measured values ​​for the flake-like glass in Examples 1-4 and Comparative Examples 1-12 are shown in Tables 3A-3C.

[0083] [Table 3A]

[0084] [Table 3B]

[0085] [Table 3C]

[0086] [Examples 5-9, Comparative Examples 13-20] The flake-like glass of Examples 5-9 and Comparative Examples 13-20 is indicated by alphabetical symbols in the "Flake-like Glass" column of Tables 4A-4B. The flake-like glass of Examples 5-9 and Comparative Examples 13-20 was subjected to surface treatment P.

[0087] The measured values ​​for the flake-like glass in Examples 5-9 and Comparative Examples 13-20 are shown in Tables 4A-4B.

[0088] [Table 4A]

[0089] [Table 4B]

[0090] [Examples 10-15, Comparative Examples 21-23] The flake-like glass of Examples 10-15 and Comparative Examples 21-23 is indicated by alphabetical symbols in the "Flake-like Glass" column of Tables 5A-5B. No surface treatment was applied to the flake-like glass of Examples 10-12 and Comparative Example 21. Surface treatment Q was applied to the flake-like glass of Examples 13-15 and Comparative Examples 22-23.

[0091] The measured values ​​for the flake-like glass in Examples 10-15 and Comparative Examples 21-23 are shown in Tables 5A-5B.

[0092] [Table 5A]

[0093] [Table 5B]

[0094] [Examples 16-18, Comparative Examples 24-25] The flake-like glass of Examples 16-18 and Comparative Examples 24-25 is indicated by alphabetical symbols in the "Flake-like Glass" column of Table 6. Surface treatment Q was applied to the flake-like glass of Examples 16-18 and Comparative Examples 24-25.

[0095] The measured values ​​for the flake-like glass in Examples 16-18 and Comparative Examples 24-25 are shown in Table 6.

[0096] [Table 6]

[0097] [Resin molded product] The resin molded articles of Examples 1-9 and Comparative Examples 1-20 were molded using the following method. Flake glass, polypropylene (Novatec BC06C, manufactured by Nippon Polypropylene Co., Ltd.), thermoplastic elastomer (ethylene-octene copolymer elastomer, Engage 8200, manufactured by Dow Chemical), and carbon black fine powder were uniformly mixed in amounts of 20% by mass, 58% by mass, 20% by mass, and 2% by mass, respectively. The resulting mixture was kneaded in an extrusion molding machine (Technovel Co., Ltd., KZW15-30MG, molding temperature: approximately 210-220°C) to obtain a resin composition containing polypropylene as the matrix resin and flake glass as a reinforcing filler. This resin composition was molded in an injection molding machine (Nissei Plastic Industrial Co., Ltd., HM7) to obtain resin molded articles. (resin composition) The flake-like glass content in this sample was 20% by mass.

[0098] The resin molded articles of Examples 10-15 and Comparative Examples 21-23 were obtained by the same method as in Examples 1-9 and Comparative Examples 1-20, except that polypropylene was replaced with polybutylene terephthalate (Duranex 2000, manufactured by Polyplastics Co., Ltd.). resin molded product( resin composition ) The flake-like glass content in this sample was 30% by mass.

[0099] The resin molded articles of Examples 16-18 and Comparative Examples 24-25 were obtained by the same method as in Examples 1-9 and Comparative Examples 1-20, except that polypropylene was replaced with polycarbonate (Yupilon S3000F, manufactured by Mitsubishi Engineering Plastics Corporation). resin molded product( resin composition ) The flake-like glass content in this sample was 30% by mass.

[0100] <Calculation of the content of flake-like glass in resin compositions> The flake glass content in the resin composition was evaluated by the ignition loss method. Specifically, an appropriate amount of the molded resin product was heated in an atmosphere of 625°C to remove components other than the flake glass, and the flake glass content in the resin composition was calculated from the difference between the mass of the molded resin product before heating and the mass of the residue (flake glass) after heating.

[0101] <Measurement of particle size distribution using laser diffraction and scattering methods> The particle size distribution was measured using laser diffraction and scattering methods on the flake glass residue generated during the calculation of the flake glass content in the resin composition. Specifically, a laser diffraction particle size distribution analyzer (Microtrac-Bell, model: MT3300EX, measurement mode: HRA) was used to disperse each type of flake glass in water and measure its particle size distribution. From the measurement results, the D10, D50, D90, D99, and D100 values ​​for the flake glass in the resin composition were read. Furthermore, from these values, the D90 / D10 and (D90×D99×D100) / D50 values ​​for the flake glass in the resin composition were calculated. In the particle size distribution, D10 was defined as the particle size corresponding to a 10% volume accumulation from the smaller particle size side, D50 as the particle size corresponding to a 50% volume accumulation from the smaller particle size side, D90 as the particle size corresponding to a 90% volume accumulation from the smaller particle size side, D99 as the particle size corresponding to a 99% volume accumulation from the smaller particle size side, and D100 as the particle size corresponding to a 100% volume accumulation from the smaller particle size side. The results are shown in Tables 3A to 36.

[0102] <Measurement of characteristic values ​​of resin molded products> The maximum tensile strength of the molded resin product was measured according to JIS K 7113. The maximum bending strength and bending modulus were measured according to JIS K 7171. The Izod impact strength UN (notched) was measured according to JIS K 7110. For the appearance evaluation of the molded resin product, a 30 mm square (3 mm thick) flat plate was molded, and the presence or absence of reflection from flake-like glass on the surface of the molded resin product was observed under natural sunlight. Surface smoothness was evaluated relative to the smoothness of the surface of the molded resin product by observing it under an optical microscope at 20x magnification, with a score of 8 or higher being considered acceptable. Scratch resistance was evaluated using a scratch hardness tester (Erichsen, pencil-type scratch hardness tester: Model 318, tip diameter 0.75 mm). A constant load (1-10 N) was applied to the flat plate used for appearance evaluation, and the scratch (degree of whitening) was drawn vertically at a speed of 1 cm per second. A score of 8 or higher was considered acceptable. The results are shown in Tables 3A-36. However, for Examples 10-15 and Comparative Examples 21-23, and Examples 16-18 and Comparative Examples 24-25, evaluation of appearance, surface smoothness, and scratch resistance was not performed or could not be performed. For example, in Examples 16-18 and Comparative Example 24, before surface treatment, in flake-shaped glass A, B, C, and a, resin decomposition occurred due to the alkaline components in the glass during the molding of the resin molded product. molded product It was not possible to obtain evaluation data for appearance, surface smoothness, and scratch resistance.

[0103] As shown in Tables 3A to 36, regardless of whether or not surface treatment was applied to the flake glass, the resin molded products of the examples showed improved impact resistance, appearance, surface smoothness, and scratch resistance compared to the resin molded products of the comparative examples. In other words, by using small-particle flake glass that satisfies the particle size characteristic parameters specified in this embodiment, it was possible to improve the impact resistance, appearance, surface smoothness, and scratch resistance of resin molded products using thermoplastic resins, including polypropylene resin, as the matrix resin.

[0104] Comparing Example 8 with Comparative Example 13, in Example 8, the values ​​of D90, D99, and D100 were the same or relatively slightly larger, but the value of (D90 × D99 × D100) / D50 was relatively smaller, resulting in greater impact strength than Comparative Example 13.

[0105] Although omitted in Tables 3A-36, the Izod impact strength N (with notch), measured according to JIS K 7110, was of good value in the examples. For example, in Examples 2 and 3, the Izod impact strength N (with notch) was 10.0 or higher.

[0106] In the above embodiment, flake-shaped glass is used as the flake-shaped substrate, but the present invention can be expected to produce similar effects even if other materials such as mica or talc are used instead of flake-shaped glass. [Industrial applicability]

[0107] The flake-like substrate of the present invention can effectively improve the impact resistance, appearance, surface smoothness, and scratch resistance of resin compositions, making it applicable to a wide range of uses. For example, a resin composition containing the flake-like substrate of the present invention and a thermoplastic resin is suitably used in fields where appearance and surface smoothness are important, and where impact resistance is crucial but fibrous fillers cannot be used, such as the interior and exterior of automobiles or electronic components. More specifically, it can be applied to exterior components such as automobile bumpers or interior components such as instrument panels made of polypropylene.

Claims

1. A flake-shaped substrate used as a filler for reinforcing a resin molded product, The aforementioned flake-like substrate has an average particle size of 0.1 to 11 μm and an average thickness of 0.1 to 1.0 μm. In the aforementioned flake-like substrate, when the particle size distribution is defined as follows, D10 is the particle size corresponding to a volume accumulation of 10% from the smaller particle size side, D50 is the particle size corresponding to a volume accumulation of 50% from the smaller particle size side, D90 is the particle size corresponding to a volume accumulation of 90% from the smaller particle size side, D99 is the particle size corresponding to a volume accumulation of 99% from the smaller particle size side, and D100 is the particle size corresponding to a volume accumulation of 100% from the smaller particle size side, D99 ≤ 35 μm, D100 ≤ 45 μm, 3 < D90 / D10, and Satisfying 700 ≤ (D90 × D99 × D100) / D50 ≤ 3200, Flake-shaped substrate. However, (D90 × D99 × D100) / D50 is calculated using μm as the unit for D50, D90, D99, and D100.

2. The aforementioned flake-like substrate is composed of at least one selected from the group consisting of glass, mica, and talc. The flake-like substrate according to claim 1.

3. Satisfying D90 / D10 ≤ 13, The flake-like substrate according to claim 1.

4. At least a portion of the surface of the flake-like substrate is covered with a surface treatment agent. The flake-like substrate according to claim 1.

5. The surface treatment agent comprises at least one selected from the group consisting of a binder component and a silane coupling agent. The flake-like substrate according to claim 4.

6. The content ratio of the surface treatment agent in the flake-like substrate is 0.05 to 2% by mass. The flake-like substrate according to claim 4.

7. A resin composition comprising a flake-like substrate and a matrix resin, The flake-like substrate contained in the resin composition is The average particle size is 0.1 to 11 μm, and the average thickness is 0.1 to 1.0 μm. In the particle size distribution, if we define D10 as the particle size corresponding to a 10% volume accumulation from the smaller particle size side, D50 as the particle size corresponding to a 50% volume accumulation from the smaller particle size side, D90 as the particle size corresponding to a 90% volume accumulation from the smaller particle size side, D99 as the particle size corresponding to a 99% volume accumulation from the smaller particle size side, and D100 as the particle size corresponding to a 100% volume accumulation from the smaller particle size side, D99 ≤ 35 μm, D100 ≤ 45 μm, 3 < D90 / D10, and Satisfying 700 ≤ (D90 × D99 × D100) / D50 ≤ 3200, Resin composition. However, (D90 × D99 × D100) / D50 is calculated using μm as the unit for D50, D90, D99, and D100.

8. The flake-like substrate contained in the resin composition satisfies D90 / D10 ≤ 13. The resin composition according to claim 7.

9. The matrix resin is a thermoplastic resin. The resin composition according to claim 7.

10. The thermoplastic resin is at least one selected from the group consisting of polypropylene, polyethylene, polybutylene terephthalate, polyethylene terephthalate, polycarbonate, polystyrene-based resin, styrene-acrylonitrile copolymer resin, polyacrylate, styrene-butadiene-acrylonitrile copolymer resin, polyarylene sulfide, polyphenylene sulfide, polyacetal, polyamide, polyamide-imide, liquid crystal polymer, polyetheretherketone, and polyetherimide. The resin composition according to claim 9.

11. The thermoplastic resin is polypropylene. The resin composition according to claim 10.

12. The thermoplastic resin is polycarbonate. The resin composition according to claim 10.

Images