JP7093639B2 - Silver coated resin particles - Google Patents

Silver coated resin particles Download PDF

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JP7093639B2
JP7093639B2 JP2018019518A JP2018019518A JP7093639B2 JP 7093639 B2 JP7093639 B2 JP 7093639B2 JP 2018019518 A JP2018019518 A JP 2018019518A JP 2018019518 A JP2018019518 A JP 2018019518A JP 7093639 B2 JP7093639 B2 JP 7093639B2
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silver
resin particles
mass
coated
parts
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JP2019139860A (en
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寛人 赤池
和彦 山▲崎▼
謙介 影山
博一 塚田
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Mitsubishi Materials Corp
Mitsubishi Materials Electronic Chemicals Co Ltd
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Mitsubishi Materials Corp
Jemco Inc
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Description

本発明は、樹脂粒子と、この樹脂粒子の表面に設けられた銀被覆層とを有する銀被覆樹脂粒子に関する。 The present invention relates to silver-coated resin particles having resin particles and a silver-coated layer provided on the surface of the resin particles.

銀被覆樹脂粒子は、銀粒子と同等の導電性を有し、かつ母粒子である樹脂粒子が銀粒子と比較して軟らかいため、変形させやすいという特性を有する。このため、銀被覆樹脂粒子は、TIM(Thermal Interface Material)材料や導電性スペーサなどの導電性材料の導電性フィラーとして利用されている。導電性フィラーとして利用する銀被覆樹脂粒子では、変形しても銀被覆層が樹脂粒子から剥離しないように、緻密性や密着性に優れていることが好ましい。 The silver-coated resin particles have the same conductivity as the silver particles, and the resin particles, which are the mother particles, are softer than the silver particles, so that they are easily deformed. Therefore, the silver-coated resin particles are used as a conductive filler for a conductive material such as a TIM (Thermal Interface Material) material or a conductive spacer. The silver-coated resin particles used as the conductive filler are preferably excellent in denseness and adhesion so that the silver-coated layer does not peel off from the resin particles even if they are deformed.

特許文献1には、緻密性や密着性に優れた銀被覆層を有する銀被覆樹脂粒子として、球状樹脂の表面に設けられた錫吸着層と、錫吸着層の表面に被覆された銀を具備し、銀被覆樹脂粒子100質量部に対して、銀の量が2~80質量部であり、かつX線回折法により測定される銀の結晶子径が18~24nmである銀被覆樹脂粒子が開示されている。 Patent Document 1 includes a tin adsorbing layer provided on the surface of a spherical resin and silver coated on the surface of the tin adsorbing layer as silver-coated resin particles having a silver-coated layer having excellent denseness and adhesion. However, the amount of silver is 2 to 80 parts by mass with respect to 100 parts by mass of the silver-coated resin particles, and the silver crystallite diameter measured by the X-ray diffractometry is 18 to 24 nm. It has been disclosed.

国際公開第2012/023566号International Publication No. 2012/023566

銀被覆層中の銀の結晶子径を一定の範囲に制御することは、銀被覆樹脂粒子の銀被覆層の緻密性を向上させるためには有効な方法の一つである。しかしながら、前記特許文献1に記載されている銀の結晶子径の範囲においては、結晶粒界のエネルギーが不安定となり易く、銀被覆樹脂粒子が一定温度に加熱されると、銀被覆層の銀が再結晶し、結晶子径が粗大化するおそれがあった。銀被覆層の結晶子径が粗大化すると、銀被覆層が母粒子である樹脂粒子から剥離しやすくなり、また、銀被覆層が剥離すると、その剥離した部分の導通が損なわれるため、導電材料として用いた際には、電気抵抗や熱抵抗の増加を招き、導電性が低下するおそれがある。 Controlling the diameter of silver crystals in the silver-coated layer within a certain range is one of the effective methods for improving the denseness of the silver-coated layer of the silver-coated resin particles. However, within the range of the silver crystallite diameter described in Patent Document 1, the energy of the crystal grain boundaries tends to be unstable, and when the silver-coated resin particles are heated to a constant temperature, the silver in the silver-coated layer is silver. Recrystallized, and there was a risk that the crystallite diameter would become coarse. When the crystallite diameter of the silver-coated layer becomes coarse, the silver-coated layer is easily peeled from the resin particles which are the mother particles, and when the silver-coated layer is peeled, the conduction of the peeled portion is impaired. When used as a particle, it may cause an increase in electrical resistance and thermal resistance, resulting in a decrease in conductivity.

この発明は、前述した事情に鑑みてなされたものであって、その目的は、高温環境下においても銀被覆層が樹脂粒子から剥離しにくく、かつ導電性に優れる銀被覆樹脂粒子を提供することにある。 The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide silver-coated resin particles in which the silver-coated layer does not easily peel off from the resin particles even in a high-temperature environment and has excellent conductivity. It is in.

上記の課題を解決するために、本発明の銀被覆樹脂粒子は、表面にパラジウム、銀ナノ粒子または錫が析出した樹脂粒子と、前記樹脂粒子の表面に接して設けられた銀被覆層とを有する銀被覆樹脂粒子であって、前記銀被覆層が、めっき層であり、Sn、Cu、Bi及びSbからなる群より選ばれる少なくとも1種以上の金属を合計で100質量ppm以上10000質量ppm以下の範囲内で含有し、残部がAgおよび不可避不純物であることを特徴としている。 In order to solve the above problems, the silver-coated resin particles of the present invention include resin particles in which palladium, silver nanoparticles or tin are precipitated on the surface, and a silver-coated layer provided in contact with the surface of the resin particles. It is a silver-coated resin particle having, the silver-coated layer is a plating layer, and at least one kind of metal selected from the group consisting of Sn, Cu, Bi and Sb is 100 mass ppm or more and 10,000 mass ppm or less in total. It is characterized in that it is contained within the range of, and the balance is Ag and unavoidable impurities.

このような構成とされた本発明の銀被覆樹脂粒子によれば、銀被覆層が、Sn、Cu、Bi及びSbからなる群より選ばれる少なくとも1種以上の金属を合計で100質量ppm以上含有するので、銀被覆層のAgの再結晶温度が高くなる。このため、銀被覆層の銀の再結晶によるAg結晶の粗大化が抑制され、高温環境下においても銀被覆層が樹脂粒子から剥離しにくくなる。また、上記金属の含有量が合計で10000質量ppm以下とされているので、電子散乱による銀被覆層の抵抗率の上昇が抑えられ、導電性が高くなる。 According to the silver-coated resin particles of the present invention having such a structure, the silver-coated layer contains at least one metal selected from the group consisting of Sn, Cu, Bi and Sb in a total amount of 100 mass ppm or more. Therefore, the recrystallization temperature of Ag in the silver coating layer becomes high. Therefore, the coarsening of Ag crystals due to the recrystallization of silver in the silver coating layer is suppressed, and the silver coating layer is less likely to be peeled from the resin particles even in a high temperature environment. Further, since the total content of the metals is 10,000 mass ppm or less, the increase in resistivity of the silver-coated layer due to electron scattering is suppressed, and the conductivity is increased.

本発明によれば、高温環境下においても銀被覆層が樹脂粒子から剥離しにくく、かつ導電性に優れる銀被覆樹脂粒子を提供することが可能となる。 According to the present invention, it is possible to provide silver-coated resin particles in which the silver-coated layer does not easily peel off from the resin particles even in a high-temperature environment and has excellent conductivity.

本発明の一実施形態に係る銀被覆樹脂粒子の断面図である。It is sectional drawing of the silver-coated resin particle which concerns on one Embodiment of this invention. 本発明の一実施形態に係る銀被覆樹脂粒子の製造方法を示すフロー図である。It is a flow figure which shows the manufacturing method of the silver-coated resin particles which concerns on one Embodiment of this invention.

以下に、本発明の実施形態について添付した図面を参照して説明する。 Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[銀被覆樹脂粒子]
図1は、本発明の一実施形態である銀被覆樹脂粒子の断面図である。
図1において、銀被覆樹脂粒子10は、樹脂粒子11と、樹脂粒子11の表面に設けられた銀被覆層12とを有する。銀被覆層12は、Sn、Cu、Bi及びSbからなる群より選ばれる少なくとも1種以上の金属を合計で100質量ppm以上10000質量ppm以下の範囲内で含有する。
[Silver-coated resin particles]
FIG. 1 is a cross-sectional view of silver-coated resin particles according to an embodiment of the present invention.
In FIG. 1, the silver-coated resin particles 10 have a resin particle 11 and a silver-coated layer 12 provided on the surface of the resin particle 11. The silver coating layer 12 contains at least one metal selected from the group consisting of Sn, Cu, Bi and Sb in a total range of 100 mass ppm or more and 10,000 mass ppm or less.

(樹脂粒子)
樹脂粒子11としては、例えば、シリコーン樹脂粒子、アラミド樹脂粒子、フッ素樹脂粒子、ポリスルホン樹脂粒子、ポリエーテル樹脂粒子、ポリイミド樹脂粒子、ポリアミドイミド樹脂粒子、エポキシ樹脂粒子、フェノール樹脂粒子、アクリル樹脂粒子、アクリル-スチレン共重合体粒子、ポリウレタン粒子、ゴム粒子、コアシェル構造を有する樹脂粒子を用いることができる。シリコーン樹脂粒子の例としては、ポリシルセスキオキサン(PSQ)樹脂粒子、ポリメチルシルセスキオサキサン(PMSQ)樹脂粒子が挙げられる。アラミド樹脂粒子の例としては、ポリメタフェニレンイソフタラミド(MPIA)樹脂粒子、ポリパラフェニレンテレフタルアミド(PPTA)樹脂粒子が挙げられる。フッ素系粒子の例としては、ポリテトラフルオロエチレン(PTFE)樹脂粒子、テトラフルオロエチレン-ヘキサフルオロプロピレン-ビニリデンフルオライド(THV)樹脂粒子、ポリビニリデンフルオライド(PVDF)系樹脂粒子、ポリクロロトリフルオロエチレン(PCTFE)系樹脂粒子、クロロトリフルオロエチレン-エチレン(ECTFE)系樹脂粒子、テトラフルオロエチレン-エチレン(ETFE)系樹脂粒子、テトラフルオロエチレン-ヘキサフルオロプロピレン(FEP)系樹脂粒子、テトラフルオロエチレン-パーフルオロアルキルビニルエーテル(PFA)系樹脂粒子等が挙げられる。ポリスルホン樹脂粒子の例としては、ポリフェニレンスルフィド(PPS)樹脂、ポリエーテル-スルホン(PES)樹脂等が挙げられる。ポリエーテル樹脂粒子の例としては、ポリエーテル・エーテル・ケトン(PEEK)樹脂粒子、ポリフェニレンエーテル(PPE)樹脂粒子等が挙げられる。フェノール樹脂粒子の例としては、ノボラック型フェノール樹脂、レゾール型フェノール樹脂、またはそれらの一部を変性したフェノール樹脂等が挙げられる。ポリウレタン粒子としては、ポリエステル系ポリウレタン粒子、ポリオール系ポリウレタン粒子等が挙げられる。ゴム粒子の例としては、シリコーンゴム粒子、フッ素ゴム粒子等が挙げられる。コアシェル構造を有する樹脂粒子の例としては、アクリル樹脂コア-シリコーン樹脂シェルの樹脂粒子が挙げられる。アクリル樹脂コア-シリコーン樹脂シェルの樹脂粒子は、アクリル樹脂粒子にシリコーン樹脂膜を被覆することにより作製される。
(Resin particles)
Examples of the resin particles 11 include silicone resin particles, aramid resin particles, fluororesin particles, polysulfone resin particles, polyether resin particles, polyimide resin particles, polyamideimide resin particles, epoxy resin particles, phenol resin particles, and acrylic resin particles. Acrylic-styrene copolymer particles, polyurethane particles, rubber particles, and resin particles having a core-shell structure can be used. Examples of the silicone resin particles include polysilesquioxane (PSQ) resin particles and polymethylsilsesquiosaxane (PMSQ) resin particles. Examples of the aramid resin particles include polymethaphenylene isophthalamide (MPIA) resin particles and polyparaphenylene terephthalamide (PPTA) resin particles. Examples of fluorine-based particles include polytetrafluoroethylene (PTFE) resin particles, tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride (THV) resin particles, polyvinylidene fluoride (PVDF) -based resin particles, and polychlorotrifluoro. Ethylene (PCTFE) -based resin particles, chlorotrifluoroethylene-ethylene (ECTFE) -based resin particles, tetrafluoroethylene-ethylene (ETFE) -based resin particles, tetrafluoroethylene-hexafluoropropylene (FEP) -based resin particles, tetrafluoroethylene -Examples include perfluoroalkyl vinyl ether (PFA) -based resin particles. Examples of the polysulfone resin particles include polyphenylene sulfide (PPS) resin, polyether-sulfone (PES) resin and the like. Examples of the polyether resin particles include polyether ether ketone (PEEK) resin particles, polyphenylene ether (PPE) resin particles, and the like. Examples of the phenol resin particles include a novolak type phenol resin, a resol type phenol resin, and a phenol resin obtained by modifying a part thereof. Examples of the polyurethane particles include polyester-based polyurethane particles and polyol-based polyurethane particles. Examples of the rubber particles include silicone rubber particles, fluorine rubber particles and the like. Examples of resin particles having a core-shell structure include resin particles of an acrylic resin core-silicone resin shell. The resin particles of the acrylic resin core-silicone resin shell are produced by coating the acrylic resin particles with a silicone resin film.

樹脂粒子11は、熱重量分析によって測定される5質量%質量減少温度が265℃以上であることが好ましい。なお、本実施形態において、5質量%質量減少温度とは、事前に物理吸着した水分を120℃で乾燥させた樹脂粒子を、不活性雰囲気中で熱重量分析した際に、25℃における初期重量から5質量%減少したときの温度を意味する。樹脂粒子11の5%質量減少温度が265℃未満である銀被覆樹脂粒子10を用いて、導電性フィラーとして含む導電性ペーストで導電膜を形成し、この導電膜をはんだ接合するときに、樹脂粒子11が熱分解して良好な導電膜を形成しにくくなるおそれがある。 The resin particles 11 preferably have a 5% by mass mass reduction temperature measured by thermogravimetric analysis of 265 ° C. or higher. In the present embodiment, the 5% by mass mass reduction temperature is the initial weight at 25 ° C. when the resin particles obtained by drying the previously physically adsorbed water at 120 ° C. are subjected to thermogravimetric analysis in an inert atmosphere. It means the temperature when it is reduced by 5% by mass from. When silver-coated resin particles 10 having a 5% mass reduction temperature of the resin particles 11 of less than 265 ° C. are used to form a conductive film with a conductive paste contained as a conductive filler, and the conductive film is solder-bonded, a resin is used. The particles 11 may be thermally decomposed to make it difficult to form a good conductive film.

樹脂粒子11の形状は、特に制限はない。球状の粒子でもよく、球状でなく異形状、例えば扁平状、板状、針状でもよい。 The shape of the resin particles 11 is not particularly limited. Spherical particles may be used, and irregular shapes such as flat, plate-shaped, and needle-shaped particles may be used instead of spherical particles.

樹脂粒子11の平均粒子径は、0.1μm以上30μm以下の範囲内にあることが好ましく、0.5μm以上10μm以下の範囲内にあることがより好ましい。樹脂粒子11の平均粒子径が0.1μm未満である場合では、樹脂粒子11が凝集し易く、また樹脂粒子11の表面積が大きくなり、導電性フィラーとして必要な導電性を得るための銀の量を多くする必要があり、また良好な銀被覆層12を形成しにくくなるおそれがある。一方、樹脂粒子11の平均粒子径が30μmを超えると、銀被覆層12の表面平滑性が低下するおそれがあり、また銀被覆樹脂粒子10同士の接触割合が減少し抵抗値が増大するなどの不具合を生じるおそれがある。なお、本明細書において、樹脂粒子11の平均粒子径とは、走査型電子顕微鏡(株式会社日立ハイテクノロジーズ製 型式名:S-4300SE)を用いて、ソフトウェア(品名:PC SEM)により、倍率5000倍で、300個の樹脂粒子の直径(粒子径)を測定し、算出された平均値をいう。樹脂粒子11が球形状以外の場合は、樹脂粒子11の長辺を平均した値を平均粒子径という。 The average particle size of the resin particles 11 is preferably in the range of 0.1 μm or more and 30 μm or less, and more preferably in the range of 0.5 μm or more and 10 μm or less. When the average particle diameter of the resin particles 11 is less than 0.1 μm, the resin particles 11 tend to aggregate, the surface area of the resin particles 11 becomes large, and the amount of silver for obtaining the conductivity required as the conductive filler. It is necessary to increase the number of particles, and it may be difficult to form a good silver-coated layer 12. On the other hand, if the average particle size of the resin particles 11 exceeds 30 μm, the surface smoothness of the silver-coated layer 12 may decrease, the contact ratio between the silver-coated resin particles 10 decreases, and the resistance value increases. There is a risk of malfunction. In the present specification, the average particle diameter of the resin particles 11 is a magnification of 5000 by software (product name: PC SEM) using a scanning electron microscope (model name: S-4300SE manufactured by Hitachi High-Technologies Co., Ltd.). The average value calculated by measuring the diameter (particle diameter) of 300 resin particles by multiplying. When the resin particles 11 have a shape other than a sphere, the value obtained by averaging the long sides of the resin particles 11 is referred to as an average particle diameter.

(銀被覆層)
銀被覆層12は、Sn、Cu、Bi及びSbからなる群より選ばれる少なくとも1種以上の金属を合計で100質量ppm以上10000質量ppm以下の範囲内で含有し、残部がAgおよび不可避不純物である。Sn、Cu、Bi及びSbは、銀被覆層12のAgの再結晶温度を上昇させて、銀被覆層12の銀の再結晶による銀結晶の粗大化を抑制する作用がある。
銀被覆層12の上記再結晶温度上昇用の添加金属(Sn、Cu、Bi、Sb)の合計含有量が100質量ppm未満であると上記の効果が得られにくくなるおそれがある。一方、上記金属の合計含有量が10000質量ppmを超えると、不純物による電子散乱のため、銀被覆層12の抵抗率が上昇して、導電性が低下するおそれがある。
以上の理由から、本実施形態では、上記金属の合計含有量を100質量ppm以上10000質量ppm以下の範囲内と設定している。上記金属の合計含有量は300質量ppm以上3000質量ppm以下の範囲内にあることが好ましい。
(Silver coating layer)
The silver coating layer 12 contains at least one metal selected from the group consisting of Sn, Cu, Bi and Sb in a total range of 100 mass ppm or more and 10,000 mass ppm or less, and the balance is Ag and unavoidable impurities. be. Sn, Cu, Bi and Sb have an effect of raising the recrystallization temperature of Ag in the silver-coated layer 12 and suppressing the coarsening of silver crystals due to the recrystallization of silver in the silver-coated layer 12.
If the total content of the additive metals (Sn, Cu, Bi, Sb) for raising the recrystallization temperature of the silver coating layer 12 is less than 100 mass ppm, the above effect may be difficult to obtain. On the other hand, if the total content of the metals exceeds 10,000 mass ppm, the resistivity of the silver-coated layer 12 may increase and the conductivity may decrease due to electron scattering due to impurities.
For the above reasons, in the present embodiment, the total content of the metals is set within the range of 100 mass ppm or more and 10,000 mass ppm or less. The total content of the metals is preferably in the range of 300 mass ppm or more and 3000 mass ppm or less.

銀被覆層12に含まれる不可避不純物は、原料及び製造工程から不回避的に混入する不純物である。不可避不純物としては、例えば、樹脂粒子の加水分解物や無電解銀めっき時における還元剤や錯体形成材料および添加剤に由来する有機物が挙げられる。具体的な元素としては、C(炭素)、H(水素)、N(窒素)、O(酸素)が挙げられる。その他には、前処理工程や無電解銀めっき時において混入する塩類が挙げられ、具体的な成分としては、Li、Na、K、NH、F、Cl、Br、SO及びNOなどが挙げられる。銀被覆層12の不可避不純物の合計含有量は、Ag(銀)に対して、0.1質量%以下であることが好ましい。 The unavoidable impurities contained in the silver coating layer 12 are impurities that are unavoidably mixed from the raw materials and the manufacturing process. Examples of the unavoidable impurities include hydrolysates of resin particles, reducing agents during electroless silver plating, complex-forming materials, and organic substances derived from additives. Specific elements include C (carbon), H (hydrogen), N (nitrogen), and O (oxygen). Other examples include salts mixed in the pretreatment process and electroless silver plating, and specific components include Li, Na, K, NH 4 , F, Cl, Br, SO 4 and NO 3 . Can be mentioned. The total content of unavoidable impurities in the silver coating layer 12 is preferably 0.1% by mass or less with respect to Ag (silver).

銀被覆樹脂粒子10の銀被覆層12の含有量、すなわち銀被覆樹脂粒子10の銀の含有量は、25質量%以上90質量%以下の範囲内にあることが好ましい。銀の含有量が25質量%未満であると、銀被覆層12に欠損が生じるおそれがある。一方、銀の含有量が90質量%を超えると、銀被覆樹脂粒子の比重が大きくなりすぎて、TIM材料や導電性スペーサなどの導電性材料に均一に分散させにくくなるおそれがある。また、銀の含有量が90質量部を超えると銀被覆層12の導電性が飽和するため、それ以上の銀を含有させることは工業的に不利となるおそれがある。 The content of the silver-coated layer 12 of the silver-coated resin particles 10, that is, the silver content of the silver-coated resin particles 10 is preferably in the range of 25% by mass or more and 90% by mass or less. If the silver content is less than 25% by mass, the silver coating layer 12 may be damaged. On the other hand, if the silver content exceeds 90% by mass, the specific gravity of the silver-coated resin particles becomes too large, and it may be difficult to uniformly disperse the silver-coated resin particles in a conductive material such as a TIM material or a conductive spacer. Further, if the silver content exceeds 90 parts by mass, the conductivity of the silver coating layer 12 is saturated, so that it may be industrially disadvantageous to contain more silver.

[銀被覆樹脂粒子の製造方法]
次に、本実施形態の銀被覆樹脂粒子の製造方法を説明する。
図2は、本発明の一実施形態に係る銀被覆樹脂粒子の製造方法を示すフロー図である。
本実施形態の銀被覆樹脂粒子の製造方法は、図2に示すように、母粒子となる樹脂粒子の表面に、無電解めっきによって銀を析出させ易くするための処理を行う前処理工程S01と、樹脂粒子に無電解銀めっきにより銀被覆層を形成する無電解銀めっき工程S02を有する。
[Manufacturing method of silver-coated resin particles]
Next, a method for producing the silver-coated resin particles of the present embodiment will be described.
FIG. 2 is a flow chart showing a method for producing silver-coated resin particles according to an embodiment of the present invention.
As shown in FIG. 2, the method for producing the silver-coated resin particles of the present embodiment includes a pretreatment step S01 in which a treatment for facilitating the precipitation of silver by electroless plating is performed on the surface of the resin particles to be the mother particles. It has an electroless silver plating step S02 for forming a silver coating layer on resin particles by electroless silver plating.

(前処理工程)
前処理工程S01では、樹脂粒子の表面に触媒を吸着させて触媒吸着樹脂粒子を得る、あるいは置換層を吸着させて置換層吸着樹脂粒子を得ることが好ましい。触媒としては、パラジウム、銀ナノ粒子を用いることができる。置換層の材料としては錫などの銀より卑な金属またはその化合物を用いることができる。
(Pretreatment process)
In the pretreatment step S01, it is preferable to adsorb the catalyst on the surface of the resin particles to obtain the catalyst-adsorbed resin particles, or to adsorb the substitution layer to obtain the substitution layer-adsorbed resin particles. Palladium and silver nanoparticles can be used as the catalyst. As the material of the substitution layer, a metal more base than silver such as tin or a compound thereof can be used.

パラジウム触媒吸着樹脂粒子は、例えば、樹脂粒子を分散させたスラリーに、パラジウム化合物と塩酸と、還元剤を加えて、樹脂粒子の表面にパラジウムを析出させることによって得ることができる。パラジウム化合物としては塩化パラジウム、硫酸パラジウム、硝酸パラジウム、及びパラジウムアンミン錯塩などの錯塩等を用いることができる。 Palladium-catalyzed adsorption resin particles can be obtained, for example, by adding a palladium compound, hydrochloric acid, and a reducing agent to a slurry in which the resin particles are dispersed to precipitate palladium on the surface of the resin particles. As the palladium compound, complex salts such as palladium chloride, palladium sulfate, palladium nitrate, and palladium-ammine complex salt can be used.

錫置換層吸着樹脂粒子は、例えば、樹脂粒子を分散させたスラリーに、錫化合物と塩酸とを加えて、樹脂粒子の表面にSnを析出させることによって得ることができる。錫化合物としては、塩化第一錫、フッ化第一錫、臭化第一錫、ヨウ化第一錫等を用いることができる。 The tin-substituted layer-adsorbed resin particles can be obtained, for example, by adding a tin compound and hydrochloric acid to a slurry in which the resin particles are dispersed to precipitate Sn on the surface of the resin particles. As the tin compound, stannous chloride, stannous fluoride, stannous bromide, stannous iodide and the like can be used.

必要に応じて、前処理工程S01を行う前に樹脂粒子に対して、プラズマ処理、オゾン処理、酸処理、アルカリ処理、酸化剤処理、シラン処理などにより表面改質を行ってもよい。これらの表面改質により、樹脂粒子の表面が活性化し、触媒または置換層および銀被覆層と、樹脂粒子との密着性が向上する。 If necessary, the resin particles may be surface-modified by plasma treatment, ozone treatment, acid treatment, alkali treatment, oxidant treatment, silane treatment, or the like before the pretreatment step S01. By these surface modifications, the surface of the resin particles is activated, and the adhesion between the catalyst or the substitution layer and the silver-coated layer and the resin particles is improved.

(無電解銀めっき工程)
無電解銀めっき工程S02では、前処理工程S01で得られた触媒吸着樹脂粒子または置換層吸着樹脂粒子に無電解銀めっきにより銀被覆層を形成する。無電解銀めっきにより銀被覆層を形成する方法としては、(1)錯化剤、還元剤等を含む水溶液中に、触媒吸着樹脂粒子または置換層吸着樹脂粒子を投入してスラリーを調製し、このスラリーに再結晶温度上昇用の添加金属(Sn、Cu、Bi、Sb)またはその塩を含有する銀塩水溶液を滴下する方法、(2)再結晶温度上昇用の添加金属またはその塩と錯化剤とを含む銀塩水溶液中に、触媒吸着樹脂粒子または置換層吸着樹脂粒子を投入してスラリーを調製し、このスラリーに還元剤水溶液を滴下する方法、(3)再結晶温度上昇用の添加金属またはその塩と、錯化剤と、還元剤とを含む銀塩水溶液に、金属触媒吸着樹脂粒子を投入してスラリーを調製し、このスラリーに苛性アルカリ水溶液を滴下する方法が挙げられる。
(Electroless silver plating process)
In the electroless silver plating step S02, a silver coating layer is formed by electroless silver plating on the catalyst adsorption resin particles or the substituted layer adsorption resin particles obtained in the pretreatment step S01. As a method of forming a silver coating layer by electroless silver plating, (1) a slurry is prepared by putting catalyst adsorption resin particles or substitution layer adsorption resin particles into an aqueous solution containing a complexing agent, a reducing agent and the like. A method of dropping an aqueous silver salt solution containing an additive metal (Sn, Cu, Bi, Sb) for increasing the recrystallization temperature or a salt thereof into this slurry, (2) complex with the additive metal for increasing the recrystallization temperature or a salt thereof. A method of preparing a slurry by putting catalyst-adsorbed resin particles or substituted layer-adsorbed resin particles into a silver salt aqueous solution containing an agent, and dropping the reducing agent aqueous solution onto the slurry, (3) for raising the recrystallization temperature. A method of preparing a slurry by adding metal catalyst adsorbing resin particles to a silver salt aqueous solution containing an added metal or a salt thereof, a complexing agent, and a reducing agent, and dropping a caustic alkaline aqueous solution onto the slurry can be mentioned.

銀塩としては、硝酸銀あるいは銀を硝酸に溶解したもの等を用いることができる。再結晶温度上昇用の添加金属またはその塩は、銀塩水溶液に溶解していることが好ましい。錯化剤としては、アンモニア、エチレンジアミン四酢酸、エチレンジアミン四酢酸四ナトリウム、ニトロ三酢酸、トリエチレンテトラアンミン六酢酸、チオ硫酸ナトリウム、コハク酸塩、コハク酸イミド、クエン酸塩又はヨウ化物塩等の塩類を用いることができる。還元剤としては、ホルマリン、ブドウ糖、イミダゾール、ロッシェル塩(酒石酸ナトリウムカリウム)、ヒドラジン及びその誘導体、ヒドロキノン、L-アスコルビン酸又はギ酸等を用いることができる。還元剤としては、ホルムアルデヒドが好ましく、少なくともホルムアルデヒドを含む2種以上の還元剤の混合物がより好ましく、ホルムアルデヒドとブドウ糖を含む還元剤の混合物が最も好ましい。 As the silver salt, silver nitrate, silver dissolved in nitric acid, or the like can be used. The added metal for raising the recrystallization temperature or a salt thereof is preferably dissolved in an aqueous silver salt solution. Examples of the complexing agent include salts such as ammonia, ethylenediamine tetraacetic acid, ethylenediamine tetraacetic acid tetrasodium, nitrotriacetic acid, triethylenetetraammine hexaacetic acid, sodium thiosulfate, succinate, succinic acidimide, citrate or iodide salt. Can be used. As the reducing agent, formarin, glucose, imidazole, Rochelle salt (potassium sodium tartrate), hydrazine and its derivatives, hydroquinone, L-ascorbic acid, formic acid and the like can be used. As the reducing agent, formaldehyde is preferable, a mixture of at least two or more reducing agents containing formaldehyde is more preferable, and a mixture of a reducing agent containing formaldehyde and glucose is most preferable.

必要に応じて、得られた銀被覆粒子に対して、表面処理を実施してもよい。表面処理剤としては、ステアリン酸、イソステアリン酸、パルミチン酸、オレイン酸などの脂肪酸、マレイン酸、コハク酸などのジカルボン酸、ポリアクリル酸などのカルボン酸系高分子、ドデシルアミン、オクタデシルアミンなどのアミン化合物、ポリエーテルアミン等のアミン系高分子、オクタデシルジスルフィドなどのスルフィド化合物、ドデカンチオールなどのチオール化合物、シランカップリング剤等が挙げられる。銀被覆粒子に対して表面処理を実施することで、後述する用途において導電性フィラーとして用いられる際に、バインダとの親和性を向上することができる。 If necessary, the obtained silver-coated particles may be surface-treated. Examples of the surface treatment agent include fatty acids such as stearic acid, isostearic acid, palmitic acid and oleic acid, dicarboxylic acids such as maleic acid and succinic acid, carboxylic acid polymers such as polyacrylic acid, and amines such as dodecylamine and octadecylamine. Examples thereof include compounds, amine-based polymers such as polyetheramine, sulfide compounds such as octadecyldisulfide, thiol compounds such as dodecanethiol, and silane coupling agents. By performing a surface treatment on the silver-coated particles, the affinity with the binder can be improved when the silver-coated particles are used as a conductive filler in the applications described later.

[用途]
本実施形態の銀被覆樹脂粒子10は、導電性フィラーとして優れており、特に、導電性接着剤、導電性フィルム(シート)、導電性ゴム(エラストマー)、導電性粘着剤、放熱シートや放熱グリス等のTIM(Thermal Interface Material)材料、または導電性スペーサなどの導電性材料の導電性フィラーとして最適に適用できる。
[Use]
The silver-coated resin particles 10 of the present embodiment are excellent as a conductive filler, and in particular, a conductive adhesive, a conductive film (sheet), a conductive rubber (elastomer), a conductive pressure-sensitive adhesive, a heat-dissipating sheet, and a heat-dissipating grease. It can be optimally applied as a conductive filler of a TIM (Thermal Interface Material) material such as, or a conductive material such as a conductive spacer.

(導電性接着剤)
導電性接着剤は、等方性の導電性接着剤(ICA:Isotropic Conductive Adhesive)と異方性の導電性接着剤(ACA:Anisotropic Conductive Adhesive)に区分される。また、バインダの形態によってペースト状、フィルム状、インク状の形態を有する。等方性の導電性接着剤は、バインダ硬化時にバインダが収縮することで、縦方向、横方向、斜方向ともにフィラーが互いに接触し、これにより接続したい導電物とフィラーが接触して導電性が得られる。等方性の導電性接着剤にてシートを形成することも可能である。異方性の導電性接着剤は、バインダ中にフィラーが分散していて接続したい導電物同士の間に異方性の導電性接着剤を挟み込む。これを縦方向に加圧することで、接続したい導電物の間のフィラーと接続したい導電物が縦方向に接触し導電性が得られる。一方、加圧されていない部分は絶縁物であるバインダを介してフィラー同士が横方向に配置され、互いに接触しないので導電性は得られない。
(Conductive adhesive)
Conductive adhesives are classified into isotropic conductive adhesives (ICA: Isotropic Conductive Adhesive) and anisotropic conductive adhesives (ACA: Anisotropic Conductive Adhesive). Further, it has a paste-like, film-like, or ink-like form depending on the form of the binder. In the isotropic conductive adhesive, the binder shrinks when the binder is cured, so that the fillers come into contact with each other in the vertical, horizontal, and diagonal directions, so that the conductive material to be connected and the filler come into contact with each other to increase the conductivity. can get. It is also possible to form the sheet with an isotropic conductive adhesive. In the anisotropic conductive adhesive, the filler is dispersed in the binder and the anisotropic conductive adhesive is sandwiched between the conductors to be connected. By pressurizing this in the vertical direction, the filler between the conductive materials to be connected and the conductive material to be connected come into contact with each other in the vertical direction, and conductivity can be obtained. On the other hand, in the non-pressurized portion, the fillers are arranged in the lateral direction via the binder which is an insulating material, and the fillers do not come into contact with each other, so that conductivity cannot be obtained.

導電性接着剤としては、例えば、異方性又は等方性の導電性ペースト、異方性又は等方性の導電性インキなどが挙げられる。導電性接着剤は、銀被覆樹脂粒子10と絶縁性のバインダ樹脂とを遊星混合機や三本ロールミルのような混練機を用いて均一に混合して調製される。導電性接着剤では、絶縁性のバインダ樹脂中に銀被覆樹脂粒子10が均一に分散する。銀被覆樹脂粒子10の含有量は、特に限定されず、用途などに応じて適宜決定されるが、バインダ樹脂100質量部に対して0.5~5質量部の範囲内が好ましい。 Examples of the conductive adhesive include an anisotropic or isotropic conductive paste, an anisotropic or isotropic conductive ink, and the like. The conductive adhesive is prepared by uniformly mixing the silver-coated resin particles 10 and the insulating binder resin using a kneader such as a planetary mixer or a three-roll mill. In the conductive adhesive, the silver-coated resin particles 10 are uniformly dispersed in the insulating binder resin. The content of the silver-coated resin particles 10 is not particularly limited and is appropriately determined depending on the intended use, but is preferably in the range of 0.5 to 5 parts by mass with respect to 100 parts by mass of the binder resin.

導電性接着剤における絶縁性のバインダ樹脂としては、特に限定されず、例えば、熱可塑性樹脂や、硬化性樹脂組成物などの熱や光によって硬化する組成物などが挙げられる。熱可塑性樹脂としては、スチレン-ブタジエンブロック共重合体、アクリル樹脂、エチレン-酢酸ビニル樹脂などが挙げられる。硬化性樹脂組成物としては、グリシジル基を有するエポキシ系モノマーやオリゴマーと、イソシアネートなどの硬化剤とを含有する樹脂組成物が挙げられる。 The insulating binder resin in the conductive adhesive is not particularly limited, and examples thereof include a thermoplastic resin and a composition such as a curable resin composition that is cured by heat or light. Examples of the thermoplastic resin include styrene-butadiene block copolymers, acrylic resins, ethylene-vinyl acetate resins and the like. Examples of the curable resin composition include a resin composition containing an epoxy-based monomer or oligomer having a glycidyl group and a curing agent such as isocyanate.

(導電性フィルム(シート))
導電性フィルムとしては、フィルム状に成形された異方性又は等方性の導電性フィルムがある。導電性フィルムは、先ず銀被覆樹脂粒子10が絶縁性のバインダ樹脂中に分散された樹脂組成物を作製し、次いでこの樹脂組成物をPET等の支持フィルムの表面に塗布することにより作製される。この樹脂組成物は銀被覆樹脂粒子10と絶縁性のバインダ樹脂とを遊星混合機や三本ロールミルのような混練機を用いて均一に混合して調製される。導電性フィルムでは、支持体フィルム上で絶縁性のバインダ樹脂中に銀被覆樹脂粒子10が均一に分散する。導電性フィルムにおける絶縁性のバインダ樹脂としては、アクリル樹脂、シリコーン樹脂、エポキシ樹脂、フェノキシ樹脂などの樹脂またはそれらの混合物を主成分として含む樹脂組成物が挙げられる。導電性フィルムにおける樹脂組成物中の銀被覆樹脂粒子10の含有量は、特に限定されず、用途などに応じて適宜決定されるが、バインダ樹脂100質量部に対して0.5~90質量部の範囲内が好ましい。
(Conductive film (sheet))
Examples of the conductive film include an anisotropic or isotropic conductive film formed into a film. The conductive film is produced by first preparing a resin composition in which silver-coated resin particles 10 are dispersed in an insulating binder resin, and then applying this resin composition to the surface of a support film such as PET. .. This resin composition is prepared by uniformly mixing the silver-coated resin particles 10 and the insulating binder resin using a kneader such as a planetary mixer or a three-roll mill. In the conductive film, the silver-coated resin particles 10 are uniformly dispersed in the insulating binder resin on the support film. Examples of the insulating binder resin in the conductive film include a resin composition containing a resin such as an acrylic resin, a silicone resin, an epoxy resin, or a phenoxy resin or a mixture thereof as a main component. The content of the silver-coated resin particles 10 in the resin composition in the conductive film is not particularly limited and is appropriately determined depending on the intended use and the like, but is 0.5 to 90 parts by mass with respect to 100 parts by mass of the binder resin. It is preferably within the range of.

(導電性ゴム(エラストマー))
導電性ゴムとしては、シート状や直方体状に成形された導電性ゴムがあり、放熱シートや導電コネクタとして使用できる。導電性ゴムは、まずバインダゴムと、加硫剤と、銀被覆樹脂粒子10とを二軸ロール等を用いて混練し、次いで加熱プレス機や乾燥機を用いて加熱や加圧を実施することにより加硫および成型することで作製される。導電性ゴムにおけるバインダゴムとしては、ニトリルゴム、アクリルゴム、スチレンブタジエンゴム、シリコーンゴム、フッ素ゴムなどが挙げられる。導電性ゴムにおける組成物中の銀被覆樹脂粒子10の含有量は、特に限定されず、用途などに応じて適宜決定されるが、バインダゴム100質量部に対して0.5~90質量部の範囲内が好ましい。
(Conductive rubber (elastomer))
As the conductive rubber, there is a conductive rubber molded into a sheet shape or a rectangular parallelepiped shape, and it can be used as a heat dissipation sheet or a conductive connector. The conductive rubber is obtained by first kneading the binder rubber, the vulcanizing agent, and the silver-coated resin particles 10 with a twin-screw roll or the like, and then heating or pressurizing the conductive rubber using a heating press or a dryer. It is made by vulcanization and molding. Examples of the binder rubber in the conductive rubber include nitrile rubber, acrylic rubber, styrene-butadiene rubber, silicone rubber, and fluororubber. The content of the silver-coated resin particles 10 in the composition of the conductive rubber is not particularly limited and is appropriately determined depending on the intended use and the like, but is in the range of 0.5 to 90 parts by mass with respect to 100 parts by mass of the binder rubber. Is preferable.

(導電性粘着剤)
導電性粘着剤としては、シート状や直方体状に成形された導電性粘着剤または導電性ゲルがあり、電気接点材料、放熱シート及び電極として使用できる。導電性粘着剤は、先ず銀被覆樹脂粒子10が絶縁性のバインダとなる粘着剤中に分散された粘着性組成物を作製し、次いでこの粘着性組成物をPET等の支持フィルムの表面に塗布することにより作製される。導電性粘着剤におけるバインダ粘着剤としては、アクリル系粘着剤、ウレタン系粘着剤、シリコーン系粘着剤などが挙げられる。導電性粘着剤における組成物中の銀被覆樹脂粒子10の含有量は、特に限定されず、用途などに応じて適宜決定されるが、バインダゴム100質量部に対して0.5~90質量部の範囲内が好ましい。
(Conductive adhesive)
Examples of the conductive pressure-sensitive adhesive include a conductive pressure-sensitive adhesive or a conductive gel molded into a sheet or rectangular parallelepiped shape, and can be used as an electric contact material, a heat-dissipating sheet, and an electrode. As the conductive pressure-sensitive adhesive, first, a pressure-sensitive adhesive composition in which silver-coated resin particles 10 are dispersed in a pressure-sensitive adhesive that serves as an insulating binder is prepared, and then this pressure-sensitive adhesive composition is applied to the surface of a support film such as PET. It is produced by doing. Examples of the binder pressure-sensitive adhesive in the conductive pressure-sensitive adhesive include acrylic-based pressure-sensitive adhesives, urethane-based pressure-sensitive adhesives, and silicone-based pressure-sensitive adhesives. The content of the silver-coated resin particles 10 in the composition in the conductive pressure-sensitive adhesive is not particularly limited and is appropriately determined depending on the intended use and the like, but is 0.5 to 90 parts by mass with respect to 100 parts by mass of the binder rubber. Within the range is preferred.

(放熱グリス)
放熱グリスとしては、不揮発性の基油、銀被覆樹脂粒子10を混合したものがあり、放熱材料として用いることができる。放熱グリスは基油と銀被覆樹脂粒子10を遊星混合機や三本ロールミルのような混練機を用いて均一に混合して調製される。放熱グリスに用いられる基油としては、シリコーンオイル系基油、鉱油系基油、合成炭化水素系基油、エステル系基油、エーテル系基油及びグリコール系基油又はそれらの組合せなどを挙げることができる。放熱グリスにおける組成物中の銀被覆樹脂粒子10の含有量は、特に限定されず、用途などに応じて適宜決定されるが、バインダゴム100質量部に対して0.5~90質量部の範囲内が好ましい。
(Thermal paste)
As the thermal paste, there is a mixture of non-volatile base oil and silver-coated resin particles 10, which can be used as a thermal paste material. The thermal paste is prepared by uniformly mixing the base oil and the silver-coated resin particles 10 using a kneader such as a planetary mixer or a three-roll mill. Examples of the base oil used for the heat-dissipating grease include silicone oil-based base oil, mineral oil-based base oil, synthetic hydrocarbon-based base oil, ester-based base oil, ether-based base oil and glycol-based base oil, or a combination thereof. Can be done. The content of the silver-coated resin particles 10 in the composition in the thermal paste is not particularly limited and is appropriately determined depending on the intended use and the like, but is within the range of 0.5 to 90 parts by mass with respect to 100 parts by mass of the binder rubber. Is preferable.

(導電性スペーサ)
導電性スペーサは、液晶表示装置において、液晶物質を挟む上下2枚の基板の配線部分を電気的に上下に接続し、かつ基板の間隙を所定の寸法に保持して使用される。導電性スペーサは、先ず銀被覆樹脂粒子10を熱硬化性樹脂や紫外光硬化型接着剤などの絶縁性のバインダ樹脂に添加した後、銀被覆樹脂粒子10とバインダ樹脂とを遊星混合機や三本ロールミルのような混練機を用いて均一に混合して樹脂組成物を調製し、次いで上下2枚の基板の配線部分のいずれか一方又は双方に上記樹脂組成物を塗布して2枚の基板を貼り合わせることにより作製される。銀被覆樹脂粒子10の含有量は、特に限定されず、用途などに応じて適宜決定されるが、バインダ樹脂100質量部に対して2~10質量部の範囲内が好ましい。
(Conductive spacer)
The conductive spacer is used in a liquid crystal display device by electrically connecting the wiring portions of two upper and lower substrates sandwiching a liquid crystal substance vertically and vertically and holding the gap between the substrates to a predetermined size. For the conductive spacer, first, the silver-coated resin particles 10 are added to an insulating binder resin such as a thermosetting resin or an ultraviolet light-curable adhesive, and then the silver-coated resin particles 10 and the binder resin are added to a planetary mixer or a third. A resin composition is prepared by uniformly mixing using a kneader such as this roll mill, and then the above resin composition is applied to either or both of the wiring portions of the upper and lower substrates to make two substrates. It is produced by pasting together. The content of the silver-coated resin particles 10 is not particularly limited and is appropriately determined depending on the intended use, but is preferably in the range of 2 to 10 parts by mass with respect to 100 parts by mass of the binder resin.

本実施形態の銀被覆樹脂粒子10を含むTIM材料や導電性スペーサは、銀被覆樹脂粒子10と絶縁性のバインダ樹脂との混合物を混練するときに高いせん断力をかけても、銀被覆層12に亀裂若しくは割れ又は銀被覆層12の樹脂粒子11からの剥離が生じにくく、その導電性がより向上する。これにより、本実施形態の銀被覆樹脂粒子10を例えば異方性の導電性接着剤に用いた場合、異方導電(横方向)の短絡を回避でき、信頼性が向上する。 The TIM material or the conductive spacer containing the silver-coated resin particles 10 of the present embodiment has the silver-coated layer 12 even when a high shearing force is applied when the mixture of the silver-coated resin particles 10 and the insulating binder resin is kneaded. Cracks or cracks or peeling of the silver coating layer 12 from the resin particles 11 are unlikely to occur, and the conductivity thereof is further improved. As a result, when the silver-coated resin particles 10 of the present embodiment are used, for example, as an anisotropic conductive adhesive, it is possible to avoid an anisotropically conductive (lateral) short circuit, and reliability is improved.

以上のような構成とされた本実施形態である銀被覆樹脂粒子10によれば、銀被覆層12が、Sn、Cu、Bi及びSbからなる群より選ばれる少なくとも1種以上の金属を合計で100質量ppm以上10000質量ppm以下の範囲内で含有するので、銀被覆層12のAgの再結晶温度が高くなる。このため、銀被覆層12の銀の再結晶によるAg結晶の粗大化が抑制され、高温環境下においても銀被覆層12が樹脂粒子11から剥離しにくくなる。 According to the silver-coated resin particles 10 of the present embodiment having the above-described configuration, the silver-coated layer 12 contains a total of at least one or more metals selected from the group consisting of Sn, Cu, Bi and Sb. Since it is contained in the range of 100 mass ppm or more and 10,000 mass ppm or less, the recrystallization temperature of Ag of the silver coating layer 12 becomes high. Therefore, the coarsening of Ag crystals due to the recrystallization of silver in the silver coating layer 12 is suppressed, and the silver coating layer 12 is less likely to be peeled from the resin particles 11 even in a high temperature environment.

以上、本発明の実施形態について説明したが、本発明はこれに限定されることはなく、その発明の技術的思想を逸脱しない範囲で適宜変更可能である。 Although the embodiments of the present invention have been described above, the present invention is not limited to this, and can be appropriately changed without departing from the technical idea of the invention.

次に、本発明を実施例により説明するが、これらは本発明を限定するものではない。 Next, the present invention will be described by way of examples, but these are not limited to the present invention.

[本発明例1]
母粒子として、平均1次粒子径が6μmである球状シリコーン樹脂粒子を用いた。
[Example 1 of the present invention]
As the mother particles, spherical silicone resin particles having an average primary particle diameter of 6 μm were used.

(前処理工程)
上記のシリコーン樹脂粒子10質量部をイオン交換水200質量部に分散させ、シリコーン樹脂粒子スラリーを調製した。このシリコーン樹脂粒子スラリー210質量部に対して、35質量%塩酸水溶液6質量部と、塩化ナトリウム30質量部、パラジウム触媒含有溶液(メルテックス社製、製品名:エンプレートアクチベータ444)10質量部とを加えて、30℃に設定した水浴中で15分撹拌して、シリコーン樹脂粒子の表面にパラジウム触媒を吸着させた。次いで、スラリーをろ過して、パラジウム触媒吸着シリコーン樹脂粒子を回収した。回収したパラジウム触媒吸着シリコーン樹脂粒子を、8質量%硫酸水溶液で洗浄し、その後水洗した。
(Pretreatment process)
A silicone resin particle slurry was prepared by dispersing 10 parts by mass of the above silicone resin particles in 200 parts by mass of ion-exchanged water. With respect to 210 parts by mass of this silicone resin particle slurry, 6 parts by mass of a 35% by mass hydrochloric acid aqueous solution, 30 parts by mass of sodium chloride, and 10 parts by mass of a palladium catalyst-containing solution (manufactured by Meltex Co., Ltd., product name: Emplate Activator 444). Was added, and the mixture was stirred for 15 minutes in a water bath set at 30 ° C. to adsorb the palladium catalyst on the surface of the silicone resin particles. The slurry was then filtered to recover the palladium-catalyzed adsorption silicone resin particles. The recovered palladium-catalyzed-adsorbed silicone resin particles were washed with an 8 mass% sulfuric acid aqueous solution and then washed with water.

(無電解銀めっき工程)
上記前処理工程で得たパラジウム触媒吸着シリコーン樹脂粒子10質量部を、イオン交換水200質量部に分散させて、パラジウム触媒吸着シリコーン樹脂粒子スラリーを調製した。次いで、パラジウム触媒吸着シリコーン樹脂粒子スラリー210質量部に対して、エチレンジアミン四酢酸四ナトリウム(錯化剤)15質量部と37質量%ホルムアルデヒド水溶液(還元剤)40質量部とを加えて、撹拌して、錯化剤及び還元剤を含むパラジウム触媒吸着シリコーン樹脂粒子スラリーを調製した。
また、別に、硝酸銀24質量部と、硝酸銅(II)0.2質量部と、クエン酸アンモニウム12質量部と、25質量%アンモニア水20質量部と、イオン交換水40質量部とを加えて、Cu含有硝酸銀水溶液を調製した。
(Electroless silver plating process)
10 parts by mass of the palladium-catalyzed adsorption silicone resin particles obtained in the above pretreatment step was dispersed in 200 parts by mass of ion-exchanged water to prepare a palladium-catalyzed adsorption silicone resin particle slurry. Next, 15 parts by mass of ethylenediamine tetraacetate tetrasodium (complexing agent) and 40 parts by mass of a 37 mass% formaldehyde aqueous solution (reducing agent) were added to 210 parts by mass of the palladium catalyst-adsorbed silicone resin particle slurry, and the mixture was stirred. , A palladium-catalyzed adsorption silicone resin particle slurry containing a complexing agent and a reducing agent was prepared.
Separately, 24 parts by mass of silver nitrate, 0.2 parts by mass of copper (II) nitrate, 12 parts by mass of ammonium citrate, 20 parts by mass of 25% by mass ammonia water, and 40 parts by mass of ion-exchanged water are added. , Cu-containing silver nitrate aqueous solution was prepared.

上記の錯化剤及び還元剤を含むパラジウム触媒吸着シリコーン樹脂粒子スラリーを撹拌しながら、このスラリーに、上記のCu含有硝酸銀水溶液を滴下して、シリコーン樹脂粒子の表面にCu含有銀被覆層を形成して、Cu含有銀被覆樹脂粒子スラリーを得た。得られたスラリーを水洗した後、ろ過、乾燥してCu含有銀被覆樹脂粒子を得た。 While stirring the palladium-catalyzed adsorption silicone resin particle slurry containing the complexing agent and the reducing agent, the Cu-containing silver nitrate aqueous solution is dropped onto the slurry to form a Cu-containing silver coating layer on the surface of the silicone resin particles. Then, a Cu-containing silver-coated resin particle slurry was obtained. The obtained slurry was washed with water, filtered, and dried to obtain Cu-containing silver-coated resin particles.

[本発明例2]
母粒子として、平均1次粒子径が2μmである球状シリコーン樹脂粒子を用いた。
[Example 2 of the present invention]
As the mother particles, spherical silicone resin particles having an average primary particle diameter of 2 μm were used.

(前処理工程)
上記のシリコーン樹脂粒子10質量部をイオン交換水300質量部に分散させ、シリコーン樹脂粒子スラリーを調製した。このシリコーン樹脂粒子スラリー310質量部に対して、35質量%塩酸水溶液5質量部と、塩化第一錫5質量部とを加えて、30℃に設定した水浴中で15分撹拌して、シリコーン樹脂粒子の表面に錫置換層を吸着させた。次いで、スラリーを水洗した後、ろ過、乾燥して錫置換層吸着シリコーン樹脂粒子を得た。
(Pretreatment process)
A silicone resin particle slurry was prepared by dispersing 10 parts by mass of the above silicone resin particles in 300 parts by mass of ion-exchanged water. To 310 parts by mass of this silicone resin particle slurry, 5 parts by mass of a 35 mass% hydrochloric acid aqueous solution and 5 parts by mass of stannous chloride were added and stirred in a water bath set at 30 ° C. for 15 minutes to obtain a silicone resin. A tin-substituted layer was adsorbed on the surface of the particles. Then, the slurry was washed with water, filtered, and dried to obtain tin-substituted layer-adsorbed silicone resin particles.

(無電解銀めっき工程)
上記前処理工程で得た錫置換層吸着シリコーン樹脂粒子10質量部を、イオン交換水500質量部に分散させて、錫置換層吸着シリコーン樹脂粒子スラリーを調製した。次いで、錫置換層吸着シリコーン樹脂粒子スラリー510質量部に対して、エチレンジアミン四酢酸四ナトリウム(錯化剤)20質量部と37質量%ホルムアルデヒド水溶液(還元剤)20質量部、D-グルコース50質量部とを加えて、撹拌して、錯化剤及び還元剤を含む錫置換層吸着シリコーン樹脂粒子スラリーを調製した。
また、別に、硝酸銀89.5質量部と、硝酸錫(IV)0.2質量部と、25質量%アンモニア水72質量部と、イオン交換水300質量部とを加えて、Sn含有硝酸銀水溶液を調製した。
(Electroless silver plating process)
10 parts by mass of the tin-substituted layer-adsorbed silicone resin particles obtained in the above pretreatment step was dispersed in 500 parts by mass of ion-exchanged water to prepare a tin-substituted layer-adsorbed silicone resin particle slurry. Next, 20 parts by mass of ethylenediamine tetraacetate tetrasodium (complexing agent), 20 parts by mass of 37 mass% formaldehyde aqueous solution (reducing agent), and 50 parts by mass of D-glucose with respect to 510 parts by mass of the tin-substituted layer-adsorbed silicone resin particle slurry. And stirred to prepare a tin-substituted layer-adsorbed silicone resin particle slurry containing a complexing agent and a reducing agent.
Separately, 89.5 parts by mass of silver nitrate, 0.2 parts by mass of tin nitrate (IV), 72 parts by mass of 25% by mass ammonia water, and 300 parts by mass of ion-exchanged water are added to prepare a Sn-containing silver nitrate aqueous solution. Prepared.

上記の錯化剤及び還元剤を含む錫置換層吸着シリコーン樹脂粒子スラリーを撹拌しながら、このスラリーに、上記のSn含有硝酸銀水溶液を滴下して、シリコーン樹脂粒子の表面にSn含有銀被覆層を形成して、Sn含有銀被覆樹脂粒子スラリーを得た。得られたスラリーを水洗した後、ろ過、乾燥してSn含有銀被覆樹脂粒子を得た。 While stirring the tin-substituted silicone resin particle slurry containing the complexing agent and the reducing agent, the Sn-containing silver nitrate aqueous solution is dropped onto the slurry to form a Sn-containing silver coating layer on the surface of the silicone resin particles. It was formed to obtain a Sn-containing silver-coated resin particle slurry. The obtained slurry was washed with water, filtered, and dried to obtain Sn-containing silver-coated resin particles.

[本発明例3]
母粒子として平均長径が10μmの扁平状アクリル-スチレン共重合体粒子を用いた。
[Example 3 of the present invention]
Flat acrylic-styrene copolymer particles having an average major axis of 10 μm were used as the mother particles.

(前処理工程)
シリコーン樹脂粒子の代わりに上記の扁平状アクリル-スチレン共重合体粒子を用いたこと以外は、本発明例1と同様の処理を行って、パラジウム触媒吸着アクリル-スチレン共重合体粒子を得た。
(Pretreatment process)
The same treatment as in Example 1 of the present invention was carried out except that the above-mentioned flat acrylic-styrene copolymer particles were used instead of the silicone resin particles to obtain palladium-catalyzed adsorption acrylic-styrene copolymer particles.

(無電解銀めっき工程)
上記前処理工程で得たパラジウム触媒吸着アクリル-スチレン共重合体粒子10質量部を、イオン交換水300質量部に分散させて、パラジウム触媒吸着アクリル-スチレン共重合体粒子スラリーを調製した。
また、別に、ムデンシルバーKSS-1(銀含有液、奥野製薬工業製)25質量部と、ムデンシルバーKSS-2(錯化剤含有液、奥野製薬工業製)100質量部と、40質量%ビスマス水溶液0.05質量部とを混合して、Bi含有無電解銀めっき液を調製した。
さらに、別に、硝酸銀12.8質量部をイオン交換水50質量部に溶解して、銀塩含有溶液を調製した。
(Electroless silver plating process)
10 parts by mass of the palladium-catalyzed adsorption acrylic-styrene copolymer particles obtained in the above pretreatment step was dispersed in 300 parts by mass of ion-exchanged water to prepare a palladium-catalyzed adsorption acrylic-styrene copolymer particle slurry.
Separately, 25 parts by mass of Muden Silver KSS-1 (silver-containing liquid, manufactured by Okuno Pharmaceutical Industry Co., Ltd.), 100 parts by mass of Muden Silver KSS-2 (silver-containing liquid, manufactured by Okuno Pharmaceutical Industry Co., Ltd.), and 40 mass by mass. A Bi-containing electroless silver plating solution was prepared by mixing with 0.05 parts by mass of a% bismuth aqueous solution.
Further, separately, 12.8 parts by mass of silver nitrate was dissolved in 50 parts by mass of ion-exchanged water to prepare a silver salt-containing solution.

上記のパラジウム触媒吸着アクリル-スチレン共重合体粒子スラリーを撹拌しながら、このスラリーに、上記のBi含有無電解銀めっき液を混合した後、ムデンシルバーKSS-3(還元剤含有液、奥野製薬工業製)1600質量部と、上記の銀塩含有溶液62.8質量部を同時に滴下し、シリコーン樹脂粒子の表面にBi含有銀被覆層を形成して、Bi含有銀被覆樹脂粒子スラリーを得た。得られたスラリーを水洗した後、ろ過、乾燥してBi含有銀被覆樹脂粒子を得た。 While stirring the above-mentioned palladium-catalyzed adsorption acrylic-styrene copolymer particle slurry, the above-mentioned Bi-containing electroless silver plating solution is mixed with this slurry, and then Muden Silver KSS-3 (reducing agent-containing solution, Okuno Pharmaceutical Co., Ltd.) (Industrial) 1600 parts by mass and 62.8 parts by mass of the above silver salt-containing solution were dropped simultaneously to form a Bi-containing silver-coated layer on the surface of the silicone resin particles to obtain a Bi-containing silver-coated resin particle slurry. .. The obtained slurry was washed with water, filtered, and dried to obtain Bi-containing silver-coated resin particles.

[本発明例4]
母粒子として粒子径30μmの球状ノボラック型フェノール樹脂粒子を用いた。
[Example 4 of the present invention]
Spherical novolak type phenol resin particles having a particle diameter of 30 μm were used as the mother particles.

(前処理工程)
シリコーン樹脂粒子の代わりに上記の球状フェノール樹脂粒子を用いたこと以外は、本発明例2と同様の処理を行って、錫置換層吸着フェノール樹脂粒子を得た。
(Pretreatment process)
The same treatment as in Example 2 of the present invention was carried out except that the above-mentioned spherical phenol resin particles were used instead of the silicone resin particles to obtain tin-substituted layer-adsorbed phenol resin particles.

(無電解銀めっき工程)
上記前処理工程で得た錫置換層吸着フェノール樹脂粒子10質量部を、イオン交換水3500質量部に分散させて、錫置換層吸着フェノール樹脂粒子スラリーを調製した。次いで、錫置換層吸着フェノール樹脂粒子10質量部に対して、エチレンジアミン四酢酸四ナトリウム(錯化剤)15質量部と37質量%ホルムアルデヒド水溶液(還元剤)15質量部とを加えて、撹拌して、錯化剤及び還元剤を含む錫置換層吸着フェノール樹脂粒子スラリーを調製した。
また、別に、硝酸銀6.8質量部、酸化アンチモン(III)0.1質量部、コハク酸イミド20質量部、炭酸水素ナトリウム1質量部、イオン交換水50質量部を混合してSb含有硝酸銀水溶液を調製した。
(Electroless silver plating process)
10 parts by mass of the tin-substituted layer-adsorbed phenol resin particles obtained in the above pretreatment step was dispersed in 3500 parts by mass of ion-exchanged water to prepare a tin-substituted layer-adsorbed phenol resin particle slurry. Next, 15 parts by mass of ethylenediamine tetraacetate tetrasodium (complexing agent) and 15 parts by mass of a 37% by mass formaldehyde aqueous solution (reducing agent) were added to 10 parts by mass of the phenol resin particles adsorbed by the tin-substituted layer, and the mixture was stirred. , A tin-substituted layer-adsorbed phenolic resin particle slurry containing a complexing agent and a reducing agent was prepared.
Separately, 6.8 parts by mass of silver nitrate, 0.1 part by mass of antimony oxide (III), 20 parts by mass of succinic acid imide, 1 part by mass of sodium hydrogen carbonate, and 50 parts by mass of ion-exchanged water are mixed to form an Sb-containing silver nitrate aqueous solution. Was prepared.

上記の錯化剤及び還元剤を含む錫置換層吸着フェノール樹脂粒子スラリーを撹拌しながら、このスラリーに、上記のSb含有硝酸銀水溶液を滴下して、フェノール樹脂粒子の表面にSb含有銀被覆層を形成して、Sb含有銀被覆フェノール樹脂粒子スラリーを得た。得られたスラリーを水洗した後、ろ過、乾燥してSb含有銀被覆樹脂粒子を得た。 While stirring the tin-substituted layer-adsorbed phenol resin particle slurry containing the complexing agent and the reducing agent, the Sb-containing silver nitrate aqueous solution is added dropwise to the slurry to form an Sb-containing silver coating layer on the surface of the phenol resin particles. It was formed to obtain an Sb-containing silver-coated phenol formaldehyde particle slurry. The obtained slurry was washed with water, filtered, and dried to obtain Sb-containing silver-coated resin particles.

[本発明例5]
(前処理工程)
母粒子として、平均1次粒子径が0.5μmである球状シリコーン樹脂粒子を用いたこと以外は、本発明例2と同様にして錫置換層吸着シリコーン樹脂粒子を得た。
[Example 5 of the present invention]
(Pretreatment process)
Tin-substituted layer-adsorbed silicone resin particles were obtained in the same manner as in Example 2 of the present invention, except that spherical silicone resin particles having an average primary particle diameter of 0.5 μm were used as the mother particles.

(無電解銀めっき工程)
上記前処理工程で得た錫置換層吸着シリコーン樹脂粒子10質量部を、イオン交換水500質量部に分散させて、錫置換層吸着シリコーン樹脂粒子スラリーを調製した。次いで、錫置換層吸着シリコーン樹脂粒子スラリー510質量部に対して、クエン酸アンモニウム(錯化剤)30質量部と、37質量%ホルムアルデヒド水溶液(還元剤)40質量部と、ロッシェル塩(錯化剤)50質量部とを加えて、撹拌して、錯化剤及び還元剤を含む錫置換層吸着シリコーン樹脂粒子スラリーを調製した。
また、別に、硝酸銀142質量部と、硝酸銅0.05質量部と、25質量%アンモニア水130質量部と、イオン交換水300質量部とを加えて、Cu含有硝酸銀水溶液を調製した。
(Electroless silver plating process)
10 parts by mass of the tin-substituted layer-adsorbed silicone resin particles obtained in the above pretreatment step was dispersed in 500 parts by mass of ion-exchanged water to prepare a tin-substituted layer-adsorbed silicone resin particle slurry. Next, with respect to 510 parts by mass of the tin-substituted layer-adsorbed silicone resin particle slurry, 30 parts by mass of ammonium citrate (complexing agent), 40 parts by mass of a 37% by mass formaldehyde aqueous solution (reducing agent), and a Rochelle salt (complexing agent). ) 50 parts by mass was added and stirred to prepare a tin-substituted layer-adsorbed silicone resin particle slurry containing a complexing agent and a reducing agent.
Separately, 142 parts by mass of silver nitrate, 0.05 part by mass of copper nitrate, 130 parts by mass of 25% by mass ammonia water, and 300 parts by mass of ion-exchanged water were added to prepare a Cu-containing silver nitrate aqueous solution.

上記の錯化剤及び還元剤を含む錫置換層吸着シリコーン樹脂粒子スラリーを撹拌しながら、このスラリーに、上記のCu含有硝酸銀水溶液を滴下して、シリコーン樹脂粒子の表面にCu含有銀被覆層を形成して、Cu含有銀被覆樹脂粒子スラリーを得た。得られたスラリーを水洗した後、ろ過、乾燥してCu含有銀被覆樹脂粒子を得た。 While stirring the tin-substituted silicone resin particle slurry containing the complexing agent and the reducing agent, the Cu-containing silver nitrate aqueous solution is dropped onto the slurry to form a Cu-containing silver coating layer on the surface of the silicone resin particles. It was formed to obtain a Cu-containing silver-coated resin particle slurry. The obtained slurry was washed with water, filtered, and dried to obtain Cu-containing silver-coated resin particles.

[本発明例6]
母粒子として、平均1次粒子径が5μmである球状シリコーンゴム粒子を用いた。
[Example 6 of the present invention]
As the mother particles, spherical silicone rubber particles having an average primary particle diameter of 5 μm were used.

(前処理工程)
上記のシリコーンゴム粒子10質量部に対して、大気プラズマ装置(SKIp-ZKB、魁半導体社製)を用いて表面改質を行った。表面改質を実施したシリコーンゴム粒子を用いたこと以外は、本発明例1と同様にして、パラジウム触媒吸着シリコーンゴム粒子を得た。
(Pretreatment process)
The surface of 10 parts by mass of the above silicone rubber particles was modified using an atmospheric plasma apparatus (SKIp-ZKB, manufactured by Kagami Semiconductor Co., Ltd.). Palladium-catalyzed-adsorbed silicone rubber particles were obtained in the same manner as in Example 1 of the present invention except that the surface-modified silicone rubber particles were used.

(無電解銀めっき工程)
上記前処理工程で得たパラジウム触媒吸着シリコーンゴム粒子10質量部を、イオン交換水200質量部に分散させて、パラジウム触媒吸着シリコーン樹脂粒子スラリーを調製した。次いで、パラジウム触媒吸着シリコーン樹脂粒子スラリー210質量部に対して、エチレンジアミン四酢酸四ナトリウム(錯化剤)20質量部と37質量%ホルムアルデヒド水溶液(還元剤)20質量部とを加えて、撹拌して、錯化剤及び還元剤を含むパラジウム触媒吸着シリコーン樹脂粒子スラリーを調製した。
また、別に、硝酸銀30質量部と、無水塩化錫(IV)0.5質量部と、クエン酸アンモニウム15質量部と、25質量%アンモニア水22質量部と、イオン交換水70質量部とを加えて、Sn含有硝酸銀水溶液を調製した。
(Electroless silver plating process)
10 parts by mass of the palladium-catalyzed adsorption silicone rubber particles obtained in the above pretreatment step was dispersed in 200 parts by mass of ion-exchanged water to prepare a palladium-catalyzed adsorption silicone resin particle slurry. Next, 20 parts by mass of ethylenediamine tetraacetate tetrasodium (complexing agent) and 20 parts by mass of a 37 mass% formaldehyde aqueous solution (reducing agent) were added to 210 parts by mass of the palladium catalyst-adsorbed silicone resin particle slurry, and the mixture was stirred. , A palladium-catalyzed adsorption silicone resin particle slurry containing a complexing agent and a reducing agent was prepared.
Separately, 30 parts by mass of silver nitrate, 0.5 parts by mass of anhydrous tin (IV) chloride, 15 parts by mass of ammonium citrate, 22 parts by mass of 25% by mass ammonia water, and 70 parts by mass of ion-exchanged water are added. A Sn-containing silver nitrate aqueous solution was prepared.

上記の錯化剤及び還元剤を含むパラジウム触媒吸着シリコーン樹脂粒子スラリーを撹拌しながら、このスラリーに、上記のSn含有硝酸銀水溶液を滴下して、シリコーン樹脂粒子の表面にSn含有銀被覆層を形成して、Sn含有銀被覆樹脂粒子スラリーを得た。得られたスラリーを水洗した後、ろ過、乾燥してSn含有銀被覆樹脂粒子を得た。 While stirring the palladium-catalyzed adsorption silicone resin particle slurry containing the complexing agent and the reducing agent, the Sn-containing silver nitrate aqueous solution is dropped onto the slurry to form a Sn-containing silver coating layer on the surface of the silicone resin particles. Then, a Sn-containing silver-coated resin particle slurry was obtained. The obtained slurry was washed with water, filtered, and dried to obtain Sn-containing silver-coated resin particles.

[比較例1]
本発明例1の無電解銀めっき工程において、硝酸銀水溶液に硝酸銅を添加しなかったこと以外は、本発明例1と同様にして銀被覆樹脂粒子を作製した。
[Comparative Example 1]
Silver-coated resin particles were produced in the same manner as in Example 1 of the present invention, except that copper nitrate was not added to the silver nitrate aqueous solution in the electroless silver plating step of Example 1 of the present invention.

[比較例2]
本発明例3の無電解銀めっき工程において、Bi含有無電解銀めっき液に添加する40質量%ビスマス水溶液の量を0.005質量部としたこと以外は、本発明例3と同様にして銀被覆樹脂粒子を作製した。
[Comparative Example 2]
Silver in the same manner as in Example 3 of the present invention, except that in the electroless silver plating step of Example 3 of the present invention, the amount of the 40% by mass bismuth aqueous solution added to the Bi-containing electroless silver plating solution was 0.005 parts by mass. The coated resin particles were prepared.

[比較例3]
本発明例1の無電解銀めっき工程において、硝酸銀水溶液に硝酸銅の代わりに硫酸銅五水和物を添加し、かつその添加量を0.6質量部としたこと以外は、本発明例1と同様にして銀被覆樹脂粒子を作製した。
[Comparative Example 3]
In the electroless silver plating step of the present invention example 1, the present invention example 1 except that copper sulfate pentahydrate was added to the silver nitrate aqueous solution instead of copper nitrate and the addition amount was 0.6 parts by mass. The silver-coated resin particles were prepared in the same manner as in the above.

[評価]
本発明例および比較例で得られた銀被覆樹脂粒子について、以下の評価を行った。その結果を下記の表1に示す。
[evaluation]
The silver-coated resin particles obtained in the examples of the present invention and the comparative examples were evaluated as follows. The results are shown in Table 1 below.

(銀および再結晶温度上昇用の添加金属(Sn、Cu、Bi、Sb)の含有量)
銀被覆樹脂粒子と希硝酸とを混合して、銀被覆層を溶解させ、ろ過し、樹脂粒子を除去した。得られた銀被覆層溶解液に含まれているAgおよびSn、Cu、Bi、Sbの量を、誘導結合プラズマ発光分光分析装置により測定し、銀被覆層の再結晶温度上昇用の添加金属の含有率を定量した。
(Contents of silver and added metals (Sn, Cu, Bi, Sb) for raising the recrystallization temperature)
The silver-coated resin particles and dilute nitric acid were mixed to dissolve the silver-coated layer and filtered to remove the resin particles. The amounts of Ag, Sn, Cu, Bi, and Sb contained in the obtained silver-coated layer solution were measured by an inductively coupled plasma emission spectrophotometer, and the added metal for raising the recrystallization temperature of the silver-coated layer was measured. The content was quantified.

(銀被覆層の再結晶性の評価)
銀被覆層の再結晶性を評価するために、加熱前の銀被覆樹脂粒子と、加熱後の銀被覆樹脂粒子について、銀被覆層の未被覆率と圧粉粉体抵抗とを下記の方法により測定した。なお、銀被覆樹脂粒子の加熱は、銀被覆樹脂粒子10gを窒素雰囲気中280℃で15分間加熱することにより行った。
(Evaluation of recrystallization of silver coating layer)
In order to evaluate the recrystallization property of the silver-coated layer, the uncoated ratio of the silver-coated layer and the powder powder resistance of the silver-coated resin particles before heating and the silver-coated resin particles after heating are determined by the following method. It was measured. The silver-coated resin particles were heated by heating 10 g of the silver-coated resin particles at 280 ° C. for 15 minutes in a nitrogen atmosphere.

(銀被覆層の未被覆率)
銀被覆樹脂粒子表面のSEM画像解析により、銀被覆層の未被覆率を測定した。具体的には、倍率3000倍で撮影した銀被覆樹脂粒子表面の写真図について、画像解析ソフト(Mountech社 Mac-View)により銀被覆層で被覆されていない未被覆部分の面積を割り出し、その割合[(未被覆部分の面積/写真図に銀被覆樹脂粒子表面の面積)×100]を算出した。なお、表1に示す値は、上記写真図に映し出された任意の銀被覆樹脂粒子100個について上記割合を算出し、これらを平均した値である。
(Uncovered ratio of silver coating layer)
The uncovered ratio of the silver-coated layer was measured by SEM image analysis of the surface of the silver-coated resin particles. Specifically, for a photographic drawing of the surface of silver-coated resin particles taken at a magnification of 3000 times, the area of the uncoated portion not covered with the silver-coated layer was determined by image analysis software (Mtech-View), and the ratio thereof. [(Area of uncoated portion / Area of surface of silver-coated resin particles in the photograph) × 100] was calculated. The values shown in Table 1 are values obtained by calculating the above ratios for 100 arbitrary silver-coated resin particles projected on the above photograph and averaging them.

(圧粉粉体抵抗)
銀被覆樹脂粒子を圧力容器に入れて、印加圧力200MPaにて圧縮し、この圧粉の体積抵抗率を抵抗率計[三菱化学社製、ロレスタ-GP(型式:UV-3101PC)]を用いて測定した。
(Powder powder resistance)
Silver-coated resin particles are placed in a pressure vessel, compressed at an applied pressure of 200 MPa, and the volume resistivity of this powder is measured using a resistivity meter [Roresta-GP (model: UV-3101PC) manufactured by Mitsubishi Chemical Corporation]. It was measured.

Figure 0007093639000001
Figure 0007093639000001

銀被覆層が添加金属を含まない比較例1の銀被覆樹脂粒子は、加熱後の未被覆率が顕著に大きくなり、また、加熱後の圧粉体抵抗率も高くなった。これは、加熱によって、銀被覆樹脂粒子の銀被覆層の銀が再結晶し、結晶が粗大化したためであると考えられる。
また、銀被覆層のBi含有量が本発明の範囲よりも少ない比較例2の銀被覆樹脂粒子は、加熱後の未被覆率が顕著に大きくなり、また、加熱後の圧粉体抵抗率も高くなった。これは、Biによる銀被覆層の銀が再結晶温度を上昇させる効果が低く、Ag結晶の粗大化を十分に抑制できなかったためであると考えられる。
さらに、銀被覆層のCu含有量が本発明の範囲よりも多い比較例3の銀被覆樹脂粒子は、加熱後の圧粉体抵抗率が高くなった。これは、Cu(不純物)による電子散乱が起きたためであると考えられる。
In the silver-coated resin particles of Comparative Example 1 in which the silver-coated layer did not contain the additive metal, the uncoated ratio after heating was remarkably large, and the resistivity of the green compact after heating was also high. It is considered that this is because the silver in the silver-coated layer of the silver-coated resin particles was recrystallized by heating and the crystals were coarsened.
Further, in the silver-coated resin particles of Comparative Example 2 in which the Bi content of the silver-coated layer is smaller than the range of the present invention, the uncoated ratio after heating is remarkably large, and the resistivity of the powder after heating is also high. It got higher. It is considered that this is because the effect of silver in the silver coating layer by Bi on raising the recrystallization temperature is low and the coarsening of Ag crystals cannot be sufficiently suppressed.
Further, the silver-coated resin particles of Comparative Example 3 in which the Cu content of the silver-coated layer was higher than the range of the present invention had a high resistivity of the powder compact after heating. It is considered that this is because electron scattering occurs due to Cu (impurities).

これに対して、銀被覆層がSn、Cu、Bi及びSbを本発明の範囲で含む本発明例1~6の銀被覆樹脂粒子は、いずれも加熱後の未被覆率が小さく、また、加熱後の圧粉体抵抗率も低くなった。
以上のことから、本発明によれば、高温環境下においても銀被覆層が樹脂粒子から剥離しにくく、かつ導電性に優れる銀被覆樹脂粒子を提供することが可能となることが確認された。
On the other hand, the silver-coated resin particles of Examples 1 to 6 of the present invention in which the silver-coated layer contains Sn, Cu, Bi and Sb within the scope of the present invention all have a small uncoated rate after heating and are heated. Later green compact resistivity was also low.
From the above, it was confirmed that according to the present invention, it is possible to provide silver-coated resin particles in which the silver-coated layer is difficult to peel off from the resin particles even in a high-temperature environment and the silver-coated resin particles are excellent in conductivity.

10 銀被覆樹脂粒子
11 樹脂粒子
12 銀被覆層
10 Silver-coated resin particles 11 Resin particles 12 Silver-coated layer

Claims (1)

表面にパラジウム、銀ナノ粒子または錫が析出した樹脂粒子と、前記樹脂粒子の表面に接して設けられた銀被覆層とを有する銀被覆樹脂粒子であって、
前記銀被覆層が、めっき層であり、Sn、Cu、Bi及びSbからなる群より選ばれる少なくとも1種以上の金属を合計で100質量ppm以上10000質量ppm以下の範囲内で含有し、残部がAgおよび不可避不純物であることを特徴とする銀被覆樹脂粒子。
A silver-coated resin particle having a resin particle in which palladium, silver nanoparticles or tin is deposited on the surface thereof, and a silver-coated layer provided in contact with the surface of the resin particle.
The silver-coated layer is a plating layer and contains at least one metal selected from the group consisting of Sn, Cu, Bi and Sb in a total range of 100 mass ppm or more and 10,000 mass ppm or less, and the balance is Silver-coated resin particles characterized by being Ag and unavoidable impurities.
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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006018995A1 (en) 2004-08-05 2006-02-23 Sekisui Chemical Co., Ltd. Conductive fine particle, method for producing conductive fine particle and electroless silver plating liquid
JP2013082784A (en) 2011-10-07 2013-05-09 Dexerials Corp Anisotropic conductive adhesive agent, method for producing the same, light emitting device, and method for manufacturing the light emitting device

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006018995A1 (en) 2004-08-05 2006-02-23 Sekisui Chemical Co., Ltd. Conductive fine particle, method for producing conductive fine particle and electroless silver plating liquid
JP2013082784A (en) 2011-10-07 2013-05-09 Dexerials Corp Anisotropic conductive adhesive agent, method for producing the same, light emitting device, and method for manufacturing the light emitting device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101947354B1 (en) * 2011-02-01 2019-02-12 구글 엘엘씨 System to share network bandwidth among competing applications

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