201244853 六、發明說明： 【發明所屬之技術領域】 本發明係、關於-種碳之含量極力;咸少之低碳銅粒子。本 發明之低碳銅粒子特別較佳用作例如用以形成印刷電路板 之電路或確保陶究電容器之外部電極之導電的銅糊之原 料。 【先前技術】 先前’作為形成電子零件等之電極或電路之方法，已知 一種將作為導電性材料之鋼粉分散於糊中而成之導電性糊 於基板上之後，锻燒該糊，並使其硬化，從而 路之方法。 电 的將導電性_於陶W之外部電極之導通 而厶B: ’將導電性糊塗佈於外部電極上，繼而藉由加埶 而進仃脫脂，其後使鋼粒 ‘ 所含有之碳之量過多的情开该情形’即銅粒子中 氣體，並且有因為該氣體藉由炮燒而產生含有碳之 自基板剝離之情況故於導體上產生裂痕，或導體 成為導電性糊之房 化法所代表之的製^方法大致分為以霧 法，結果，若採用乾式法 H離子之還原之濕式 點。然而於乾式h J有石及不易混入銅粒子中之優 -方面’根據濕式法，：：:立:較小之銅粒子有極限。另 銅粒子的優點，作另 可谷易製造次微米級之微小之 中之源自分散劑或、^方面’有較多混入存在於反應系統 戈還原劑之碳的傾向。 I63139.doc 201244853 作為此種製造方法之一種，本申請者提出一種銅粉之製 造方法，其如首先於具有二價之銅離子之銅鹽水溶液中混 合驗金屬氫氧化物，而生成氧化銅，並加入還原糖，藉此 使氧化銅還原成氧化亞銅’進而藉由加入肼系還原劑而還 原氧化亞銅，藉此生成金屬銅者，且預先於銅鹽水溶液中 投入錯合劑之後，混合反應當量相當於110〜16〇之鹼金屬 氫氧化物，並進行熟化反應以生成黑色之氧化銅（參照專 利文獻1)。於該方法中，使用還原糖作為還原劑，因此源 自其之碳有混入銅粒子中之可能性。 因此，本申請者提出一種銅粒子之製造方法，其係首先 使用磷酸化合物代替包含利用濕式法製造銅粒子時所使用 之有機化合物之分散劑（參照專利文獻2)。使用磷酸化合物 之銅粒子之製造方法除此以外，亦例如揭示於專利文獻3 中。 [先前技術文獻] [專利文獻] [專利文獻1]曰本專利特開2003-342621號公報 [專利文獻2]曰本專利特開2009-74152號公報 [專利文獻3]曰本專利特開平9—256007號公報 【發明内容】 [發明所欲解決之問題] 根據專利文獻2所揭示之方法，可獲得碳之含量較少之 鋼粒子。然而於該方法中，為了提高所獲得之銅粒子之分 散性，又為了使粒徑一致，而於步驟之中途進行清洗，並 163139.doc 201244853 調整反應系統之pH值 或為了獲得均勻之粒徑之銅粒子 雖PH值之調整係為了提高分散性 而必需之操作，但就生產 性之方面而言，增加此部分作業步驟並非有利。又，即便 進行此種pH值調整，分散性之程度仍並非應滿意者。 於專利文獻3所揭示之方法中，為了控制反應而使用 大量之磷酸，因此有所獲得.之銅粒子中所含有之磷之量增 多的傾向。就導電性之方面及燒結溫度下降之方面而言， 含有大量磷之銅粒子有起到負作用之情況，又，廢液；之 碟之量亦增多，從而就環境負載之方面而t_，並非較佳。 因此’本發明之課題在於提供—種各種特性比上述之先 前技術之銅粒子更提高的低碳銅粒子。 [解決問題之技術手段] 本發明係藉由提供-種低碳銅粒子，而解決上述之課題 者。上述低碳銅粒子之特徵在於： 碳之含量未達〇.〇1重量％，且碌之含量未達〇 〇ι重量％ , 以下之式所定義之變異係數cv(c〇efficient of Variance) 值為10〜35%， 並且為表面之-部分具有非曲面部之大致球狀。 CV值(％) = (σ/£)5〇)χ1〇〇 (式中σ表不圖像解析中之粒子之粒徑之標準偏差， 表π圖像解析中之粒子之5〇%體積累積粒徑)。 又’本發明提供—種低碳銅粒子之製造方法作為上述之 低碳鋼粒子之較佳製造方法，其特徵在於： 其係包括還原步驟之製造低碳銅粒子之方法，上述還原 I63139.doc 201244853 步驟係於不存在含碳化學物種（其中，含碳銅化合物除外) 及含磷化學物種之情況下，於含有銅化合物之水性液中添 加還原劑，而進行鋼之還原， 且於存在2.1〜8 m()I/L之無助於還原反應之物質的條件 下’藉由還原而生成銅粒子。 [發明之效果] 根據本發明，提供一種一 且粒度分佈一致之銅粒子。 之銅粒子。 面減少碳之含量，一面為微粒 又，提供一種耐熱收縮性較高 【實施方式】 以下對本發明’基於其較佳實施形態而進行說明。特徵 之-為本發明之銅粒子係減少碳之含量者。本發明之銅粒 子中之奴之含量為未達〇〇1重量％之極少量且較佳為 0.005重量％以下 進而較佳為0.001重量％以下。碳之含量 係使用作為堀場製作所劁土八 F •造之妷分析裝置之EMIA-320V， 並以利用氧氣氣流中之揪，造έ ^ τ < /然麂-紅外線吸收方式之測定而求 出。具體而言，於姆诉击从x °中放入0.5 g之試樣，進而放入助燃 劑（鎮金屬1.5 g+錫金屬〇 g)，並將該坩堝設置於裝置中 而進行測定。 於後步驟中’對銅粒子之表面施加包含有機化合物之表 面處理劑的情形時，去除該表面處理劑之後，㈣碳之含 量已♦匕3有機化合物之表面處理劑通常於 20(TC〜赋之加熱下，自銅粒子之表面消除的情況，因 此於本發明中 對於大氣環境中，於400〇c下加熱3〇分鐘 163139.doc 201244853 後之銅粒子，以上述之方法測定碳之含量。 藉由將本發明之銅粒子中所含有之碳之量設為未達〇 重量％，從而將該銅粒子作為原料而製造之導電性糊成為 如下者，於锻燒使用該銅粒子而形成之導體時，不易引起 於。亥導體上產生裂痕，或自基板剝離之問題。其原因在 、於：因減少銅粒子中所含有之碳之量，故起因於碳而產生 之氣體之量減少。關於用以使銅粒子中所含有之碳之量減 少之具體手段，如下文所述。 雖並未明確本發明之銅粒子所含有之碳以何種狀態存 在，但推測例如或以有機化合物或碳酸根之狀態而存在。 不過石厌以何種狀態存在’於本發明中並非臨界性。 本發明之銅粒子亦具有粒徑一致之特徵。即，亦具有粒 度分佈鮮明之特徵。本發明之銅粒子之粒度分佈之程度可 藉由變異係數CV值而表示。cv值係使用圖像解析中之粒 子之粒徑之標準偏差σ與圖像解析中之粒子之50〇/〇體積累 積粒徑Dso，藉由CV(%)=((j/D5〇)x100而算出。於本發明之 銅粒子中，CV值為1 〇〜350/〇，較佳為π〜34〇/〇，進而較佳為 • 12 3〇/。。藉由CV值在該範圍内，從而於製成糊膜時，起 到如下有利之效果：可形成填充性較高且細密之膜，進而 亦容易控制膜厚。 於上述之圖像解析中，使用掃描式電子顯微鏡（SEM，201244853 VI. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a low-carbon copper particle which is extremely low in content of carbon. The low carbon copper particles of the present invention are particularly preferably used as a raw material for, for example, a copper paste for forming a circuit of a printed circuit board or for ensuring conduction of an external electrode of a ceramic capacitor. [Prior Art] As a method of forming an electrode or a circuit for an electronic component or the like, a conductive paste obtained by dispersing a steel powder as a conductive material in a paste on a substrate is known, and the paste is calcined. The method of hardening it and thus the road. Electrical conductivity _ is turned on by the external electrode of the ceramic W and 厶 B: 'The conductive paste is applied to the external electrode, and then degreased by twisting, and then the carbon contained in the steel particle' Excessive amount of the situation is the case, that is, the gas in the copper particles, and there is a crack in the conductor due to the fact that the gas is peeled off from the substrate by the firing of the gas, or the conductor becomes a conductive paste. The method of forming the method is roughly divided into a fog method, and as a result, if a dry method is used, the wet point of the reduction of H ions is used. However, in the dry type, there is a stone and it is difficult to mix into the copper particles. According to the wet method, :::: The smaller copper particles have a limit. In addition, the advantage of the copper particles is that the sub-micron-sized ones are derived from the dispersing agent or have a tendency to be more mixed with the carbon present in the reaction system. I63139.doc 201244853 As one of such manufacturing methods, the present applicant proposes a method for producing copper powder, which firstly forms a copper oxide by first mixing a metal hydroxide in an aqueous solution of a copper salt having a divalent copper ion. And adding reducing sugar, thereby reducing copper oxide to cuprous oxide, and then reducing the cuprous oxide by adding a lanthanide reducing agent, thereby generating metal copper, and pre-mixing the copper salt aqueous solution into the wrong agent, mixing The reaction equivalent amount corresponds to an alkali metal hydroxide of 110 to 16 Å, and is subjected to a aging reaction to form black copper oxide (see Patent Document 1). In this method, a reducing sugar is used as a reducing agent, so that the carbon derived therefrom has a possibility of being mixed into the copper particles. Therefore, the present applicant has proposed a method for producing copper particles by first using a phosphoric acid compound instead of a dispersant containing an organic compound used for producing copper particles by a wet method (see Patent Document 2). In addition to the method for producing copper particles using a phosphoric acid compound, for example, Patent Document 3 is disclosed. [PRIOR ART DOCUMENT] [Patent Document 1] [Patent Document 1] Japanese Laid-Open Patent Publication No. 2003-342621 (Patent Document 2) Japanese Patent Laid-Open Publication No. 2009-74152 (Patent Document 3) SUMMARY OF THE INVENTION [Problem to be Solved by the Invention] According to the method disclosed in Patent Document 2, steel particles having a small carbon content can be obtained. However, in this method, in order to improve the dispersibility of the obtained copper particles, in order to make the particle size uniform, the cleaning is performed in the middle of the step, and 163139.doc 201244853 adjusts the pH value of the reaction system or in order to obtain a uniform particle size. Although the adjustment of the pH of the copper particles is necessary to improve the dispersibility, it is not advantageous to increase the work steps in terms of productivity. Moreover, even with this pH adjustment, the degree of dispersibility is not satisfactory. In the method disclosed in Patent Document 3, a large amount of phosphoric acid is used in order to control the reaction, so that the amount of phosphorus contained in the obtained copper particles tends to increase. In terms of electrical conductivity and reduction in sintering temperature, copper particles containing a large amount of phosphorus have a negative effect, and the amount of waste liquid is also increased, so that in terms of environmental load, t_ is not Preferably. Therefore, the object of the present invention is to provide low carbon copper particles having various characteristics higher than those of the prior art copper particles described above. [Technical means for solving the problem] The present invention solves the above problems by providing a low-carbon copper particle. The low carbon copper particles are characterized in that: the carbon content is less than 〇1〇%, and the content of the turbidity is less than 重量% by weight, and the coefficient of variation cv(c〇efficient of Variance) defined by the following formula It is 10 to 35%, and is a substantially spherical shape having a non-curved portion. CV value (%) = (σ/£)5〇)χ1〇〇 (where σ is not the standard deviation of the particle size of the particles in the image analysis, and the π% volume accumulation of the particles in the π image analysis Particle size). Further, the present invention provides a method for producing a low carbon copper particle as a preferred method for producing the above low carbon steel particles, characterized in that it comprises a method for producing low carbon copper particles in a reduction step, the above reduction I63139.doc 201244853 The step is to add a reducing agent to the aqueous liquid containing the copper compound in the absence of carbon-containing chemical species (excluding carbon-containing copper compounds) and phosphorus-containing chemical species, and to reduce the steel, and in the presence of 2.1 ~8 m () I / L does not contribute to the reduction of the reaction under the conditions of the formation of copper particles by reduction. [Effects of the Invention] According to the present invention, there is provided a copper particle having a uniform particle size distribution. Copper particles. The surface is reduced in the amount of carbon, and the fine particles are provided on the one hand, and the heat shrinkage resistance is high. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described based on preferred embodiments thereof. Characteristic - the copper particles of the present invention are those which reduce the carbon content. The content of the slave in the copper particles of the present invention is an extremely small amount of less than 1% by weight, preferably 0.005% by weight or less, more preferably 0.001% by weight or less. The carbon content is obtained by using EMIA-320V, which is a 妷 • • • • • • , , , , , , , 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气 氧气. Specifically, Yum v. puts a 0.5 g sample from x °, and then puts a combustion aid (a town metal 1.5 g + tin metal 〇 g), and the ruthenium is placed in the apparatus for measurement. In the case where a surface treatment agent containing an organic compound is applied to the surface of the copper particles in the subsequent step, after the surface treatment agent is removed, the content of the carbon (4) has been 匕 3 organic compound surface treatment agent is usually 20 (TC ~ Fu In the case of heating, the surface of the copper particles is removed. Therefore, in the present invention, the copper particles are heated at 400 〇c for 3 minutes, 163139.doc 201244853, and the carbon content is measured by the above method. By using the amount of carbon contained in the copper particles of the present invention to be less than 5% by weight, the conductive paste produced by using the copper particles as a raw material is formed by calcining the copper particles. In the case of a conductor, it is less likely to cause cracks or peeling from the substrate. The reason for this is that the amount of carbon generated by the carbon particles is reduced by reducing the amount of carbon contained in the copper particles. The specific means for reducing the amount of carbon contained in the copper particles is as follows. Although it is not clear in which state the carbon contained in the copper particles of the present invention exists, For example, it may exist in the state of an organic compound or a carbonate. However, the state in which the stone is present is not critical in the present invention. The copper particles of the present invention also have the characteristics of uniform particle size, that is, the particle size distribution is also distinct. The degree of particle size distribution of the copper particles of the present invention can be expressed by the coefficient of variation CV. The cv value is the standard deviation σ of the particle size of the particles in the image analysis and 50 粒子 of the particles in the image analysis. /〇 volume cumulative particle diameter Dso, calculated by CV (%) = ((j / D5 〇) x 100. In the copper particles of the present invention, the CV value is 1 〇 ~ 350 / 〇, preferably π ~ 34 〇/〇, and further preferably, 12 3 〇/. By the CV value being within the range, when the paste is formed, the following advantageous effects are obtained: a film having a high filling property and a fine film can be formed. Further, it is easy to control the film thickness. In the above image analysis, a scanning electron microscope (SEM,
Scanmng Electron Microscopy)，將粒子擴大 5000〜2〇〇〇〇 倍，而進行直接觀察。基於所獲得之SEM圖像，實測粒子 之面積，並根據所測定之面積而算出圓等效直徑，且將該 163139.doc 201244853 值作為粒徑。又，Dm係基於所測定之粒徑而算出圓球換 算體積’並定義成體積累積5〇%時之粒徑。測定樣品數均 設為5 0 〇個以上。 本發明之銅粒子除具有粒徑一致之特徵外，亦具有為微 粒之特徵。具體而言，本發明之銅粒子之Da較佳為〇丨〜々 μηι。藉由Dm在該範圍内，從而帶來如下有利效果：變得 可形成膜厚較薄，且間距寬度較窄之導電膜。就使該有利 之效果更明顯之觀點而言，本發明之銅粒子之Dm進而較 佳為〇.13~30111’更佳為〇.15〜2卩111。 本發明之銅粒子之形狀係於表面之一部分具有非曲面部 之大致球狀。例如，於表面之一部分具有平面部，且使該 平面部為於端部上具有脊線或角部之大致球狀。此種形Z 與例如利用霧化法製造之表面成為平滑之曲面之球狀的銅 粒子之形狀明顯不同。變為於表面之一部分具有非曲面部 之大致球狀的銅粒子雖與圓球之粒子相比，填充性較低， 但與片狀之粒子相比，填充性較高，因此於由包含該銅粒 子之糊形成導電膜之情形時’具有如下優點··該導電膜顯 現出充分之導電性，並且脫氣體性優異。就不易於導電膜 上產生裂痕等方面而言，脫氣體性優異之情況較為有利。 此種形狀之銅粒子可按照下述之較佳製造方法而獲得。 除減少碳之含量之情況以外，亦將麟之含量未達〇〇1重 量％之情況作為本發明之低碳銅粒子之特徵之一。於本說 明書中，所謂「破之含量未達〇〇1重量％」係指⑴不含有 填，及（2)即便含有鱗，亦作為不可避免之微量混入成分或 163139.doc 201244853 不可避免之微量殘留成分，而少量含有未達〇.〇丨重量％。 即於本發明中，排除故意使磷含於低碳銅粒子中之情;兄。 藉由不含有磷，或少量含有未達0.01重量％之磷，從而變 得可使本發明之低碳銅粒子之電阻下降。除此以外，於使 本發明之低碳銅粒子燒結時，可抑制該粒子之燒結溫度下 降。於將本發明之低碳銅粒子用於例如粉末冶金之情形 時，可抑制燒結溫度之下降之情況變得有利。且，於使本 發明之低碳銅粒子燒結時，可使原因在於燒結之體積變化 之溫度依賴性緩和。就可防止裂痕之產生之方面而言，可 使體積變化之溫度依賴性緩和之情況較為有利。 又，本發明之低碳銅粒子較佳為實質上不含有碳及磷以 外之元素。所謂實質上不含有係排除故意添加該元素之情 況之宗旨，例如如下宗旨：容許於製品之製造過程中，存 在不可避免混入之微量之元素或雖未完全藉由純化而去除 之不可避免殘留之微量的元素。 繼而’對本發明之銅粒子之較佳製造方法進行說明。於 本製k方法令於包含銅化合物之水性液中添加還原劑， 而進行銅之還原。於該方法中，自其開始直至結束，於不 存在含碳化學物種之情況下(其中，乙酸銅或甲酸銅等含 :銅化合物除外)進行全部之步驟…自其開始直至結 ，於不存在含軌學物種之情況下進行全部之步驟。作 為含碳化學物種，可别m A ， 種有機化合物（例如，烴、 f、缓酸m嗣、有機石夕院、胺基酸等）、含 反之離子種類（例如㈣離子或碳酸離子等）、碳材料（例 163139.d〇c 201244853 如黑鉛或石墨等）。作為含磷化學物種’可列舉正磷酸； 焦磷酸及三聚磷酸等多磷酸；三偏磷酸等偏磷酸；正磷酸 鈉及正磷酸鉀等正磷酸鹽；焦磷酸鈉及焦磷酸鉀等多磷酸 鹽；三偏磷酸鈉及三偏磷酸鉀等偏磷酸鹽等。 於本製造方法中，首先製備含有二價之銅化合物之水性 液（以下亦稱為「含銅液」）。作為銅化合物，例如可使用 硫酸銅、硝酸銅或該等之水合物等水溶性銅化合物。又， 亦可使用乙酸銅作為銅化合物。雖乙酸銅為含碳化合物， 但源自乙酸銅之碳為微量’因此源自乙酸銅之碳不會大量 含於目標銅粒子中。該等銅化合物中，硫酸銅五水合物及 硝酸銅之水溶性較高，從而可提高水溶液中之銅濃度， 又，容易獲得粒度之均勻性較高之銅粒子，因此適合使 用0 m〇l/L〜3.8 mol/L之銅化合物。藉由以該範圍之比例含有都 化合物，而進行生產性優異之合成，因此較佳。 含銅液係藉由於水中使二價之銅化合物溶解或分散而! 備。作為銅化合物之溶解方法，例如可列舉預先設為射 水=狀態’於其中添加銅化合物，並進行揽拌之方法。京 =均勻之粒徑之銅粒子的觀點而言，製備含銅液時之2 >皿較佳為4〇t〜㈣，進而較佳為贼〜阶。 二上述方式獲得之含銅液中添加驗性化合物，而生居 氧化銅（CuO)。作為主t α 舉氫氧化鈉或氫氧_ /之㈣化合物，例如可歹1 W鹼金屬之氫氧化物及氨。該等越 163139.doc 201244853 性化合物可單獨使用或混合2種以上使用。所生成之氧化 銅係以微小之固體狀粒子之狀態懸浮於液體中。 作為向含銅液添加鹼性化合物之方法例如可列舉預先 設為攪拌含銅液之狀態，於其中添加鹼性化合物之水溶 液，並進行攪拌之方法。此時之液溫可較佳設為 4〇C 90C，進而較佳設為50«>c〜8〇〇c。若液溫在該範圍 ^ ’則一次粒子之凝聚較少，而容易獲得粒徑之均句性較 高之銅粒子，因此較佳。於使用2種以上之組合作為驗性 化合物之情形時，亦可同時添加該等，或亦可依序添加。 鹼性化合物之添加於含銅液之量，其相對於丨當量之鋼 化合物之鹼性化合物之量設為較佳成為1〇5當量〜丨$當 量’進而較佳成為Μ當量〜1>3當量之量。藉由使鹼性化： 物之添加量在該範圍内，從而容易獲得粒徑之均句性較高 之銅粒子’因此較佳。所謂銅化合物及鹼性化合物之當； 係指作為各自之酸之當量及作為鹼基之當量。 較佳為藉由向含銅液添加鹼性化合物而生 後’亦繼續攪拌液體，而進行熟化。熟化較佳為進行^分 鐘〜6 〇分鐘，特佳為進行2 〇分鐘〜4 〇分鐘。藉由熟化而充分 生成氧化銅，藉此而容易獲得粒度之均勻性較高之銅粒 子，因此較佳。 乂上述方式生成氧化銅後，繼而進行第旧原步驟。於 本還原步驟中，藉由-面授拌液體一面添加還原劑，從而 使液體十所含有之氧化銅還原成氧化亞鋼(c，。因此， 於本還原步驟令使用之還原劑係具有使氧化銅還原成氧化 I63139.doc 201244853 亞銅之作用者。作為該還原劑，例如可使用肼。 於本還原步驟t ’相對於！莫耳之液射所含有之銅， 添加較佳為0·】莫耳〜3莫耳，進而較佳為〇3莫耳〜15莫耳 之還原劑。若還原劑之添加量在該範圍内，則氧化銅之對 氧化亞銅之還原反應充分進行，其結果，因不易引起目標 銅粒子之一次粒子之凝聚，故而較佳。 較佳為藉由本還原步驟而使氧化銅還原成氧化亞銅之 後’亦使液體之㈣繼續而進行熟化。熟化較佳為進行⑺ 分鐘〜60分鐘，特佳為進行2Q分鐘〜4()分鐘。藉由熟化，從 而充分生成氧化亞銅，並因不易引起目標鋼粒子之一次粒 子之凝聚，故而較佳。 第1還原步驟結束後，繼而進行第2還原步驟。於本還肩 步驟中’藉由—面攪拌液體一面添加還原劑，而使液體中 所3有之氧化亞銅還原成銅，而生成銅粒子。因此，於本 還原㈣中使用之還原㈣具有使氧化亞鋼還原成銅之作 用者。作為該還原劑，例如可使用肼。 於第2還原步驟令，相對於（莫耳之液體中所含有之銅， 添加較佳為〇.3莫耳〜3莫耳，進而較佳為⑶莫耳〜2莫耳之 還原劑可藉由將還原劑之使用量設定為該範圍内，從而 始終良好地獲得目標銅粒子。 本發明者等人進行研究，結果判明如下情況：於第2還 原步驟中之銅粒子生成時，就始終良好地獲得粒徑一致之 銅冰子的方面而§，於反應系統中預先大量含有無助於還 原反應之水溶性物f之情況較為有利。為了使銅粒子之粒 163139.doc 12 201244853 徑一致，重要的是極力抑制銅粒子產生時之液體之pH值的 變動，結果，藉由預先大量含有無助於還原反應之水溶性 物質於液體中，從而該水溶性物質發揮作為緩衝劑之作 用，而抑制ρίί值之變動◊可是，若使無助於還原反應之水 溶性物質過度存在於液體中，則有液體之導電率變得過 高，從而反應之控制變得不容易，且粒度分佈變寬之傾 白就°亥觀點而s，較佳為將銅粒子生成時之存在於液體 中之該水各性物質的濃度設定為2 · 1〜& m〇i/L。就一面控制 反應，一面更抑制pH值之變動之觀點而言，進而較佳為將 該水溶性物質之濃度設定為2.丨〜3 m〇l/L，更佳為設定為 2.2-2.7 mol/L。 作為無助於還原反應之該水溶性物質，可列舉於水中進 行電離而產生之陽離子及陰離子均無助於自氧化亞銅生成 銅粒子者。作為此種陽離子，可列舉：鈉離子、鉀離子、 敍離子、質子等。作為陰離子，彳列舉：硫酸離子、破酸 離子、硝酸離子、氣化物離子、氫氧化物離子等。作為包 含該等陽離子與陰離子之組合之水溶性物質的具體例，可 列舉：NaN〇3、NaC1、叫⑽4、叫⑶3等水溶性鹽或 NaOH等驗金屬氫氧化物。進而作為該水溶性物質，亦可 列舉與水反應而產生之離子無助於自氧化亞銅生成銅粒子 者。作為此種水溶性物質之具體例，可列舉作為與水反應 而生成銨離子之物質之NH3等。 上述之水溶性物質較佳為於開始第2還原步驟之前存在 於液體中。為了該目的，（丨）可於第i還原步驟後，不將氧 163139.doc •13· 201244853 化亞銅自液體分離，而交付於第2還原步驟中，且於第1還 原步驟後，第2還原步驟前，將該水溶性物質以其濃度成 為2.卜8 mol/L之方式添加於液體中。作為其他方法，（2) 亦可於第1還原步驟後，將氧化亞銅自液體分離，並進行 沖洗等操# ’之後製備包含分離之氧化亞銅，且包含 2.1〜8 mol/L之上述之水溶性物質的漿料，從而將製備而成 之漿料交付於第2還原步驟中。 又，因為存在添加之化學物種，故於開始第2還原步驟 前，已經於液體中存在2.1〜8 mol/L之濃度之水溶性物質的 情形時’無需進行（1)及（2)之操作。 根據為進行本製造方法而添加之各種化合物之添加量， 於第1還原步驟結束之時間點，有液體中之上述之水溶性 物質之濃度6經滿足上述之範圍的.清況。於此種情形時， 無需使用追加之水溶性物質，而可繼續進行第2還原步 驟。 較佳為藉由第2還原步驟，從而使氧化亞銅還原成鋼 後，亦使液體之攪拌繼續而進行熟化。熟化較佳為進行 分鐘〜120分鐘，特佳為進行4〇分鐘〜9〇分鐘。藉由熟化， 從而充分進行還原，並因不易引起目標之銅粒子之一次粒 子之凝聚，故而較佳。 藉由以上之方法而製造之銅粒子因自步驟 、、*吞 束，於不存在含碳化學物種（其中，含碳銅化合物除外）之 情況下進行反應，故原理上完全不含有碳，或即便含有 碳，亦成為極力減少其量者。並且，成為粒徑一致且抑 163139.doc 14 201244853 制一次粒子之凝聚者。銅粒子即便含有碳，其碳亦為不可 避免地混入銅粒子中者。於本製造方法中，不進行故意使 碳含於銅粒子中之操作。 並且’藉由以上之方法而製造之銅粒子因自步驟開始直 至結束’於不存在含磷化學物種之情況下進行反應，故原 理上完全不含有磷’或即便含有磷’亦成為極力減少其量 者。銅粒子即便含有磷，其磷亦為不可避免地混入銅粒子 中者。於本製造方法中，不進行故意使磷含於銅粒子中之 操作。 藉由以上之方法，而獲得目標低碳銅粒子。以上述方式 獲得之低碳銅粒子例如較佳用作導電性糊之原料。該導電 性糊係含有包含本發明之低碳銅粒子之金屬粒子、有機媒 劑、玻璃料者。該有機媒劑包含樹脂成分與溶劑。作為樹 脂成分，例如可列舉：丙烯酸系樹脂、環氧樹脂、乙基纖 、准素竣基乙基纖維素等。作為溶劑，可列舉松油醇及二 ^松油醇等㈣系溶劑或乙基三甘醇及τ基卡必醇等輕系 ♦劑°作為玻璃料’可列舉：侧石夕玻璃、硼石夕鋇玻璃、硼 =辞玻璃等。I電性糊中之金屬粉之比例較佳為設為 36〜97·5重量％。破璃料之比例較佳為設為1.5〜14重量％。 某Μ之比例較佳為設為丨〜⑼重量％。作為該導電性糊 之金屬粒子，亦可僅使用本發明之低碳銅粒子，或亦可 組合該低碳銅粒子與鱗狀等其他形狀之銅粒子而使用。藉 由組^本發明之低碳鋼粒子與其他形狀之銅粒子而使用， 從而各易精密進行4 逆仃糊之黏度調整。 163139.doc •15· 201244853 以上述方式獲得之導電性糊較佳用於例如形成印刷電路 板之電路、確保陶瓷電容器之外部電極等導電、 EMI(Electromagnetic Interference，電磁干擾）對策。 [實施例] 以下，藉由實施例，對本發明進行更詳細之說明。然而 本發明之範圍並不受該實施例之限制。只要未事先說明， 則「％」意指「重量％」。 [實施例1] (1) 含有銅之水溶液之製備 於65°c之6.5 L之純水中，以銅之濃度成為以下之表"斤 示之值的方式’添加硫酸銅五水合物，並進行搅拌，而獲 得含有銅之水溶液。 (2) 氧化銅之生成 於攪拌該水溶液之狀態下，於該水溶液中，同時添加表 1所示之2種鹼性化合物，而於液體中生成氧化銅。並且， 繼續攪拌30分鐘。鹼性化合物之添加量係設為相對於}莫 耳之銅’成為表1所示之值的量。 (3) 氧化銅還原成氧化亞銅 繼而，添加肼及氨水， 進行第1還原反應，從而使氧化 銅還原成氧化亞銅》並且繼續攪拌3〇分鐘。肼及氨之添加Scanmng Electron Microscopy), which expands the particles by 5000 to 2 times and directly observes them. Based on the obtained SEM image, the area of the particles was measured, and the circle equivalent diameter was calculated from the measured area, and the value of 163139.doc 201244853 was taken as the particle diameter. Further, Dm is a particle diameter calculated by calculating the sphere-converted volume ' based on the measured particle diameter and defining the volume accumulation by 5 %. The number of samples to be measured was set to 50 or more. The copper particles of the present invention are also characterized by fine particles in addition to the characteristics of uniform particle size. Specifically, Da of the copper particles of the present invention is preferably 〇丨~々 μηι. By the fact that Dm is in this range, there is an advantageous effect that it becomes possible to form a conductive film having a thin film thickness and a narrow pitch width. From the viewpoint of making the advantageous effect more conspicuous, the Dm of the copper particles of the present invention is more preferably from 13.13 to 30111', preferably from 1515 to 2卩111. The shape of the copper particles of the present invention is such that a portion of the surface has a substantially spherical shape having a non-curved portion. For example, a portion of the surface has a flat portion, and the flat portion has a substantially spherical shape having ridges or corners on the end portion. Such a shape Z is significantly different from the shape of a spherical copper particle having a smooth curved surface, for example, which is produced by an atomization method. The substantially spherical copper particles having a non-curved surface portion on one of the surfaces have lower filling properties than the particles of the spherical surface, but have higher filling properties than the flake-shaped particles, and therefore include When the paste of copper particles forms a conductive film, it has the following advantages. The conductive film exhibits sufficient conductivity and is excellent in degassing properties. In the case where cracks or the like are not easily formed on the conductive film, it is advantageous in that the gas removal property is excellent. Copper particles of such a shape can be obtained by the following preferred production methods. In addition to the case where the content of carbon is reduced, the case where the content of lin is less than 1% by weight is also one of the characteristics of the low carbon copper particles of the present invention. In the present specification, the term "the content of the broken amount is less than 1% by weight" means that (1) does not contain a filling, and (2) even if it contains scales, it is an unavoidable trace amount of a component or 163139.doc 201244853 The residual component, while the small amount contains less than 〇.〇丨% by weight. That is, in the present invention, it is excluded that the phosphorus is intentionally contained in the low carbon copper particles; By not containing phosphorus, or a small amount containing less than 0.01% by weight of phosphorus, the electric resistance of the low carbon copper particles of the present invention can be lowered. In addition, when the low carbon copper particles of the present invention are sintered, the sintering temperature of the particles can be suppressed from decreasing. When the low carbon copper particles of the present invention are used in, for example, powder metallurgy, it is advantageous to suppress the decrease in the sintering temperature. Further, when the low carbon copper particles of the present invention are sintered, the reason may be that the temperature dependence of the volume change of the sintering is moderated. In terms of preventing the occurrence of cracks, it is advantageous to alleviate the temperature dependence of the volume change. Further, the low carbon copper particles of the present invention are preferably elements which do not substantially contain carbon or phosphorus. The term "substantially does not contain the purpose of excluding the intentional addition of the element" is, for example, the purpose of allowing a trace amount of an element which is inevitably mixed in the production process of the product or an inevitable residue which is not completely removed by purification. Trace elements. Next, a preferred method of producing the copper particles of the present invention will be described. In the present k method, a reducing agent is added to an aqueous liquid containing a copper compound to carry out reduction of copper. In this method, from the beginning to the end, in the absence of a carbon-containing chemical species (wherein copper acetate or copper formate or the like: except for the copper compound), all the steps are carried out... from the beginning to the end, in the absence of Carry out all the steps in the case of orbital species. As a carbon-containing chemical species, it is possible to distinguish between organic compounds (for example, hydrocarbons, f, acid-lowering m嗣, organic stone plants, amino acids, etc.), and vice ionic species (for example, (tetra) ions or carbonate ions). Carbon materials (eg 163139.d〇c 201244853 such as black lead or graphite). Examples of the phosphorus-containing chemical species include orthophosphoric acid; polyphosphoric acid such as pyrophosphoric acid and tripolyphosphoric acid; metaphosphoric acid such as trimetaphosphoric acid; orthophosphate such as sodium orthophosphate and potassium orthophosphate; and polyphosphoric acid such as sodium pyrophosphate and potassium pyrophosphate. Salt; metaphosphate such as sodium trimetaphosphate and potassium trimetaphosphate. In the production method, an aqueous solution containing a divalent copper compound (hereinafter also referred to as "copper-containing liquid") is first prepared. As the copper compound, for example, a water-soluble copper compound such as copper sulfate, copper nitrate or a hydrate thereof can be used. Further, copper acetate can also be used as the copper compound. Although copper acetate is a carbon-containing compound, the carbon derived from copper acetate is a small amount. Therefore, carbon derived from copper acetate is not contained in a large amount in the target copper particles. Among these copper compounds, the water solubility of copper sulfate pentahydrate and copper nitrate is high, so that the copper concentration in the aqueous solution can be increased, and copper particles having a high uniformity of particle size can be easily obtained, so that it is suitable to use 0 m〇l /L~3.8 mol/L of copper compound. It is preferred to contain a compound in a ratio of this range to carry out a synthesis excellent in productivity. The copper-containing liquid is prepared by dissolving or dispersing a divalent copper compound in water. As a method of dissolving the copper compound, for example, a method in which a copper compound is added to the water-injection state in advance and is stirred is mentioned. From the viewpoint of the copper particles having a uniform particle diameter, the 2 > dish in the preparation of the copper-containing liquid is preferably 4 〇 t 〜 (4), and further preferably thief-order. 2. The copper-containing liquid obtained in the above manner is added with an inspective compound, and is home to copper oxide (CuO). As the main t α , a sodium hydroxide or a hydroxide ( 4 ) compound, for example, a hydroxide of an alkali metal and ammonia can be used. The above-mentioned 163139.doc 201244853 compounds may be used singly or in combination of two or more. The generated copper oxide is suspended in the liquid in the form of minute solid particles. The method of adding a basic compound to the copper-containing liquid is, for example, a method in which a copper-containing liquid is stirred in advance, and an aqueous solution of a basic compound is added thereto and stirred. The liquid temperature at this time is preferably set to 4 〇 C 90C, and further preferably set to 50 «> c 〜 8 〇〇 c. If the liquid temperature is in this range ^', the primary particles are less aggregated, and copper particles having a higher uniformity of particle size are easily obtained, which is preferable. When two or more combinations are used as the test compound, they may be added at the same time or may be added sequentially. The amount of the basic compound added to the copper-containing liquid is preferably from 1 to 5 equivalents to about 丨$ equivalents, and more preferably to Μ equivalents to 1%, based on the amount of the basic compound of the ruthenium equivalent steel compound. The amount of equivalent. When the amount of addition of the substance is within this range, it is easy to obtain copper particles having a high uniformity in particle size, which is preferable. The term "copper compound and basic compound" means the equivalent of each acid and the equivalent of the base. It is preferred to carry out aging by adding a basic compound to the copper-containing liquid and then continuing to stir the liquid. The aging is preferably carried out for 2 minutes to 6 minutes, and particularly preferably for 2 minutes to 4 minutes. Since copper oxide is sufficiently formed by aging, copper particles having a high uniformity in particle size are easily obtained, which is preferable. After the copper oxide is formed in the above manner, the first step is performed. In the present reduction step, the reducing agent is added to the surface of the mixed liquid to reduce the copper oxide contained in the liquid ten to the oxidized sub-steel (c. Therefore, the reducing agent used in the present reduction step has oxidation resistance. Copper is reduced to the role of oxidized I63139.doc 201244853 cuprous. As the reducing agent, for example, ruthenium can be used. In the present reduction step t', the copper contained in the liquid injection is preferably 0. Moor ~ 3 moles, and further preferably 〇 3 moles to 15 moles of reducing agent. If the amount of the reducing agent added is within this range, the reduction reaction of copper oxide with cuprous oxide proceeds sufficiently, and the result is sufficiently Preferably, it is preferred that the primary particles of the target copper particles are agglomerated, and it is preferred that the reduction of the copper oxide to cuprous oxide by the reduction step is followed by aging of the liquid (four). The curing is preferably carried out. (7) Minutes to 60 minutes, particularly preferably for 2Q minutes to 4 minutes. It is preferred to form cuprous oxide by aging, and it is preferable because the primary particles of the target steel particles are not easily aggregated. After the completion of the step, the second reduction step is carried out. In the present return step, 'the reducing agent is added while stirring the liquid, and the cuprous oxide in the liquid is reduced to copper to form copper particles. The reduction (IV) used in the reduction (IV) has a function of reducing the oxidized sub-steel to copper. As the reducing agent, for example, ruthenium can be used. In the second reduction step, it is contained in the liquid of the Moir. Preferably, the copper is preferably added in an amount of 〇3 mol to 3 mol, and more preferably (3) mol 2 to 2 mol of the reducing agent can be obtained by setting the amount of the reducing agent to be within the range. The inventors of the present invention conducted research, and as a result, it was found that when the copper particles in the second reduction step are formed, the aspect of the copper ice having the same particle diameter is always obtained satisfactorily, in the reaction system. It is advantageous to contain a large amount of the water-soluble substance f which does not contribute to the reduction reaction in advance. In order to make the diameter of the particles of the copper particles 163139.doc 12 201244853, it is important to suppress the fluctuation of the pH of the liquid when the copper particles are generated. As a result, by preliminarily containing a large amount of a water-soluble substance which does not contribute to the reduction reaction in the liquid, the water-soluble substance functions as a buffer, and the fluctuation of the value of ρίί is suppressed, but if the water is not soluble in the reduction reaction, If the substance is excessively present in the liquid, the conductivity of the liquid becomes too high, and the control of the reaction becomes difficult, and the whitening of the particle size distribution becomes s, preferably copper particles are generated. In the case where the concentration of the water-containing substance present in the liquid is set to 2·1 to & m〇i/L, it is more preferable to control the reaction while suppressing the change of the pH value. The concentration of the water-soluble substance is set to 2. 丨~3 m〇l/L, more preferably set to 2.2-2.7 mol/L. As the water-soluble substance which does not contribute to the reduction reaction, it can be exemplified by ionization in water. The cations and anions produced do not contribute to the formation of copper particles from cuprous oxide. Examples of such a cation include a sodium ion, a potassium ion, a sulphur ion, and a proton. As the anion, cerium is exemplified by a sulfate ion, an acid-breaking ion, a nitrate ion, a vapor ion, a hydroxide ion, and the like. Specific examples of the water-soluble substance containing the combination of the cation and the anion include a water-soluble salt such as NaN〇3, NaC1, (10)4, and (3)3, or a metal hydroxide such as NaOH. Further, as the water-soluble substance, those produced by the reaction with water may not be used to form copper particles from cuprous oxide. Specific examples of such a water-soluble substance include NH3 which is a substance which reacts with water to form an ammonium ion. The above water-soluble substance is preferably present in the liquid before the start of the second reduction step. For this purpose, (丨) may be separated from the liquid after the ith reduction step, without the oxygen 163139.doc •13·201244853 cuprous, and after the first reduction step, after the first reduction step, 2 Before the reduction step, the water-soluble substance is added to the liquid at a concentration of 2. 8 mol/L. As another method, (2) after the first reduction step, the cuprous oxide is separated from the liquid, and after washing, etc., the separated cuprous oxide is prepared and contains 2.1 to 8 mol/L. The slurry of the water-soluble substance is used to deliver the prepared slurry to the second reduction step. Moreover, since there is an added chemical species, it is necessary to carry out the operations of (1) and (2) when a water-soluble substance having a concentration of 2.1 to 8 mol/L is present in the liquid before the start of the second reduction step. . According to the addition amount of each of the compounds added for carrying out the production method, at the time point when the first reduction step is completed, the concentration 6 of the above-mentioned water-soluble substance in the liquid satisfies the above range. In this case, the second reduction step can be continued without using an additional water-soluble substance. It is preferred that after the reduction of the cuprous oxide into steel by the second reduction step, the stirring of the liquid is continued to be matured. The aging is preferably carried out in minutes to 120 minutes, and particularly preferably in the course of 4 minutes to 9 minutes. It is preferable to carry out the reduction sufficiently by aging, and it is difficult to cause aggregation of primary particles of the copper particles of the target. The copper particles produced by the above method are reacted in the absence of a carbon-containing chemical species (excluding the carbon-containing copper compound) since the steps are swallowed, so that in principle, no carbon is contained at all, or Even if it contains carbon, it is the one that tries to reduce its amount. Furthermore, it is a coherent particle size uniform and suppresses the primary particles of 163139.doc 14 201244853. Even if the copper particles contain carbon, the carbon is inevitably mixed into the copper particles. In the present production method, the operation of intentionally causing carbon to be contained in the copper particles is not performed. And 'the copper particles produced by the above method are reacted from the beginning to the end of the step in the absence of a phosphorus-containing chemical species, so that in principle, no phosphorus is contained at all or even if it contains phosphorus, it is extremely reduced. Quantity. Even if the copper particles contain phosphorus, the phosphorus is inevitably mixed into the copper particles. In the present production method, the operation of intentionally causing phosphorus to be contained in the copper particles is not performed. The target low carbon copper particles are obtained by the above method. The low carbon copper particles obtained in the above manner are preferably used, for example, as a raw material of the conductive paste. The conductive paste contains metal particles, an organic medium, and a glass frit containing the low carbon copper particles of the present invention. The organic vehicle contains a resin component and a solvent. The resin component may, for example, be an acrylic resin, an epoxy resin, an ethyl cellulose or a non-primary mercaptoethyl cellulose. Examples of the solvent include a solvent such as terpineol and bis-terpineol, a light solvent such as ethyltriethylene glycol or τ-carbitol, and a light ray as a glass frit. Xi Xi glass, boron = glass, and so on. The ratio of the metal powder in the electric paste is preferably set to 36 to 97.5% by weight. The proportion of the glass frit is preferably set to 1.5 to 14% by weight. The ratio of a certain enthalpy is preferably set to 丨~(9)% by weight. As the metal particles of the conductive paste, only the low carbon copper particles of the present invention may be used, or the low carbon copper particles and other shapes of copper particles such as scaly may be used in combination. By using the low carbon steel particles of the present invention and the copper particles of other shapes, it is easy to precisely adjust the viscosity of the 4 reverse paste. 163139.doc • 15· 201244853 The conductive paste obtained in the above manner is preferably used for, for example, a circuit for forming a printed circuit board, and for ensuring electric conduction and EMI (Electromagnetic Interference) countermeasures such as external electrodes of the ceramic capacitor. [Examples] Hereinafter, the present invention will be described in more detail by way of examples. However, the scope of the invention is not limited by the embodiment. "%" means "% by weight" unless otherwise stated. [Example 1] (1) Preparation of an aqueous solution containing copper In a pure water of 6.5 L at 65 ° C, copper sulfate pentahydrate was added in such a manner that the concentration of copper became the value of the following table. And stirring was carried out to obtain an aqueous solution containing copper. (2) Formation of copper oxide In the state in which the aqueous solution was stirred, two kinds of basic compounds shown in Table 1 were simultaneously added to the aqueous solution to form copper oxide in the liquid. Also, continue to stir for 30 minutes. The amount of the basic compound added was an amount which became a value shown in Table 1 with respect to the copper of the mole. (3) Reduction of copper oxide to cuprous oxide Next, adding hydrazine and ammonia water, the first reduction reaction is carried out to reduce the copper oxide to cuprous oxide, and stirring is continued for 3 minutes. Addition of hydrazine and ammonia
應之水溶性物質的濃度係如表1所示。 163139.doc -16- 201244853 (4)氧化亞銅之還原成銅粒子 繼而於液中添加肼，進行第2還原反應’從而使氧化亞 銅還原成銅。繼續授拌1小時，而使反應結束。肼之添加 量係設為相對於1莫耳之銅，成為表1所示之值的量。反應 、结束後，使用布氏漏斗，對所獲得之聚料進行過滤，繼而 • 利用純水進行清洗’進而加以乾燥，從而獲得目標銅粒 子。利用SEM觀察該銅粒子，結果如圖i所示，確認該銅 粒子係於表面之一部分具有非曲面部之大致球狀者。 [實施例2〜4] 採用以下之表1所示之條件，除此以外，以與實施例i相 同之方式獲得銅粒子。利用SEM觀察該銅粒子，結果確認 實施例2〜4之銅粒子係於表面之一部分具有非曲面部之大 致球狀者。 [比較例1及2] 於本比較例中，依照專利文獻3(曰本專利特開平9· 256007號公報）之實施例1及2，而製造銅粒子。將製造條 件示於表1。將比較例2中獲得之銅粒子之;§em圖像示於圖 [比較例3] 依照專利文獻2所揭示之實施例1而製造銅粒子。首先， 於6.5 L之純水中投入6000 g之硫酸銅五水合物，並進行授 拌，其後，一面保持液溫為50°C ’ 一面於該硫酸銅水溶液 中添加2537 ml之氨水溶液（濃度25%)而進行中和，從而獲 得銅鹽化合物漿料。並且，將銅鹽化合物漿料靜置3〇分 I63139.doc 17- 201244853 鐘’而使其熟化。雖目前為止將銅鹽化合物漿料之液溫保 持為50°C，但熟化後，將液溫調整至45〇c。 繼而’以銅鹽化合物漿料之銅濃度成為2.〇 m〇i/L之方式 添加水’而調整液量。將該銅鹽化合物漿料保持為pH值 6.3、液溫50°C之條件，並於其中連續添加45〇 §之肼—水 合物與591 ml之氨水溶液（濃度25%)，從而製成氧化亞銅 漿料（第1還原處理p並且，為了完全進行還原反應，進而 繼續攪拌30分鐘。 其後，為了進行再製漿清洗，而於氧化亞銅漿料中加入 純水，從而將液量調整為丨8 L，之後進行靜置，而使氧化 亞銅粒子沈澱，重複進行抽出14 L之靜置後之上清液的操 作直至pH值成為4.7 ^並且，加入8 L之加熱之純水，使總 液量為12 L ’並將液溫維持為价，且將銅濃度調整為2〇 rnol/L，從而將其作為清洗氧化亞銅漿料。 於銅濃度調整後之清洗氧化亞銅漿料中，添加3.〇2居之 次亞磷酸敍’並攪拌5分鐘。 再次，以 >青洗氧化亞鋼聚料之銅濃度成為2 〇 之方 式添加水’並調整液量。於該清洗氧化亞鋼漿料中，添加 〇〇 g之肼水σ物。繼而，進而進行i 5分鐘搜摔，而使 還原反應το王進仃’並使銅粒子還原析出(第2還原處理)。 [比較例4] 採用以下之表1所示之條件’除此以外，以與實施例"目 同之方式獲得鋼粒子。 I63139.doc 201244853 【I<〕 第2還原反應j 肼 (mol/Culmol) 1.56 1 1.20 1 0.98 0.78 4.16 3.30 1.56 0.87 坺靶1 W逄1 ^ B 1 1 1 1 1 0.02 1 1 水溶性物質之添加 全體 濃度 (mol/L) 卜 <N 寸 CN cm' so <N 1 0.036 1 1 0.035 1 1 o.oi 1 〇 <Ν 種類 1 'NaCI NaNQ3 | ςη Z 1 1 1 1 過濾 难 难 第1還原反應(CuO—Cu20) 氨水 (mol/Culmol) 0.40 1 0.40 1 0.40 0.40 1 1 0.40 0.40 肼 (mol/Culmol) 卜 __ 卜 卜 1 1 0.58 0.58 1 CuO之生成 NaOH j (mol/Culmol) 0.87 1 0.87 1 0.87 0.87 1 1 1 0.87 ^氨水 j (mol/Culmol) 0.89 1 0.89 1 0.89 0.89 1 1 1.72 0.89 填化合物之 添加濃度 (mmoI/Culmol) 1 1 1 1 59.7 41.8 1 1 丨含有銅之水溶液 溫度 CC) Ό V〇 V*J VO Vi Ό v-> Ό 1 30-80 1 30-80 濃度 (mol/L) 卜 ΓΟ 卜 rn 卜 rn r- ro Ο VO ο 卜 CN 實施例1 |實施例2 1 實施例3 實施例4 比较例1 1比較例2 1 比較例3 比較例4 -19- 163139.doc 201244853 [評價] 對實施例及比較例中獲得之銅粒子所含有之碳之量，利 用先前所述之碳分析進行測定，並利用ICp(inductively coupled plasma，感應耦合電漿）發光分析測定磷之量。 又’藉由圖像解析’而測定於實施例及比較例中獲得之銅 粒子之Dw及CV值。進而，對於實施例及比較例中獲得之 銅粒子，利用以下之方法測定壓粉電阻值。進而，對於實 施例及比較例中獲得之銅粒子，利用以下之方法製備漿 料，從而測定由該漿料製作而成之膜之表面粗燥度。將該 等結果示於以下之表2 ^進而，對於實施例丨與比較例j , 及實施例3與比較例2，利用以下之方法，對利用熱機械分 析之體積變化之測定進行測定。將該等結果示於圖3(a)及 (b)。 [壓粉電阻值之測定] 使用壓粉電阻測定系統（三菱化學PD_41)與電阻率測定 器（三菱化學MCP-T600)，測定壓粉電阻值。將15 g之試樣 投入探針圓筒中，並向PD-41安裝探針單元。使用MCp_ T600，對藉由油壓千斤頂而施加1〇〇〇以4之壓力時之電阻 值進行測定。由測定之電阻值與試樣厚度，而算出壓粉電 阻值。 [由漿料製作而成之膜之表面粗燥度之測定] 將於實施例及比較例中獲得之銅粒子與溶劑（95 g之松油 醇與5 g之乙基纖維素之混合物），以丨：i之重量比加以混 合，而製成漿料。使用混合機（Thinky(股），ARE_25〇)，使 163139.doc 201244853 該漿料以2000 rpm旋轉45秒，而進行預混練。繼而於三輥 式研磨機（AIMEX(股），模型RMZ-1)中，進而對漿料進行 精練。輥之間隙設定為5 μπι。使用30 μηι之敷料器 (YOSHIMITSU SEIKI(股），模型YR-1)，將以上述方式獲 得之漿料塗佈於玻璃基板上，而形成塗膜。於80°C下，使 該塗膜乾燥5分鐘。使用表面粗燥度形狀測定器（東京精密 (股），Surfcoml3 0A)，對以上述方式獲得之膜之表面粗燥 度Ra及Rmax進行測定。 [利用熱機械分析之體積變化之測定] 使用 SEIKO Instrument Inc.製造之 SEIKO EXSTAR 6000。試樣係使用於模具中測取0.5 g之成為測定對象之銅 粒子，並藉由壓力機，以1 ton/cm2之壓力進行加壓，從而 成為顆粒者。將該試樣裝於熱分析裝置中，並測定測定前 之試樣長度（裝置係進行自動測定）。試樣係以49 mN之壓 力而由上側壓住。於氣體環境1% H2-N2(150 mL/min)，升 溫速度l〇°C /min之條件下使溫度上升時，測定體積變化。 [表2] C量 (重量％) P量 (PPm) D50 _ CV值 (%) 壓粉電阻值 (Ω-cm) Ra (μηι) Rmax ㈣ 實施例1 0.005 <10 0.42 34.7 9.9E-03 0.135 1.147 實施例2 0.007 <10 0.87 33.2 7.2E-03 0.144 1.203 實施例3 0.006 <10 1.79 21.8 1.2E-03 0.379 3.311 實施例4 0.005 <10 3.76 12.1 7.8E-04 0.421 3.776 比較例1 0.007 0.2 wt% 0.62 45.1 3.8E+01 0.212 2.021 比較例2 0.005 0.2 wt% 1.80 38.3 5.0E+00 0.402 3.895 比較例3 0.005 470 1.76 55.2 6.2E-02 0.685 4.579 比較例4 0.006 <10 2.07 81.3 9.6E-03 1.680 11.210 根據表2所示結果明確可知：於各實施例中獲得之銅粒 子之碳之含量較低，分散性良好。又，可知於各實施例中 163139.doc •21 · 201244853 獲得之銅粒子之壓粉電阻值較低。進而，可知使用於各實 施例中獲得之銅粒子而形成之臈之表面性良好。相對於 此，可知雖於比較例I及2中獲得之銅粒子之碳之含量較 低’但與實施例之銅粒子相比，缺乏分散性，並且凝聚。 進而，根據圖3(a)及（b)所示之結果明確可知：以相同程度 之粒徑進行比較之情形時，不含有p之鋼粒子（本發明品） 之对熱收縮性亦高於含有p之銅粒子（比較品）。 【圖式簡單說明】 圖1係於實施例1中獲得之銅粒子之掃描式電子顯微鏡圖 像。 圖2係於比較例2中獲得之銅粒子之掃描式電子顯微鏡圖 像。 @ 3⑷及⑻係表示對於實施例及比較例中獲得之銅粒 子藉由熱機械分析而測定體積變化之結果之圖。 163139.doc •22-The concentration of the water-soluble substance should be as shown in Table 1. 163139.doc -16- 201244853 (4) Reduction of cuprous oxide into copper particles Then, hydrazine is added to the liquid to carry out a second reduction reaction, thereby reducing copper oxide to copper. Continue to mix for 1 hour and let the reaction end. The amount of ruthenium added was set to the amount shown in Table 1 with respect to 1 ohm of copper. After the reaction and the end, the obtained polymer was filtered using a Buchner funnel, and then • washed with pure water and dried to obtain a target copper particle. When the copper particles were observed by SEM, as shown in Fig. 1, it was confirmed that the copper particles were substantially spherical in a part of the surface having a non-curved surface portion. [Examples 2 to 4] Copper particles were obtained in the same manner as in Example i except for the conditions shown in Table 1 below. When the copper particles were observed by SEM, it was confirmed that the copper particles of Examples 2 to 4 were substantially spherical in a part of the surface having a non-curved portion. [Comparative Examples 1 and 2] In the present comparative example, copper particles were produced in accordance with Examples 1 and 2 of Patent Document 3 (Japanese Laid-Open Patent Publication No. Hei 9-256007). The manufacturing conditions are shown in Table 1. The copper particles obtained in Comparative Example 2; §em image are shown in the figure [Comparative Example 3] Copper particles were produced in accordance with Example 1 disclosed in Patent Document 2. First, 6000 g of copper sulfate pentahydrate was added to 6.5 L of pure water, and the mixture was mixed. Thereafter, while maintaining the liquid temperature at 50 ° C, 2537 ml of an aqueous ammonia solution was added to the aqueous copper sulfate solution ( Neutralization was carried out at a concentration of 25%) to obtain a copper salt compound slurry. Further, the copper salt compound slurry was allowed to stand for 3 minutes to form an I63139.doc 17-201244853 hr. Although the liquid temperature of the copper salt compound slurry has been maintained at 50 ° C, the liquid temperature has been adjusted to 45 ° C after aging. Then, the amount of liquid was adjusted by adding water to the copper concentration of the copper salt compound slurry to be 2. 〇 m〇i/L. The copper salt compound slurry was maintained at a pH of 6.3 and a liquid temperature of 50 ° C, and 45 〇 of the hydrazine-hydrate and 591 ml of an aqueous ammonia solution (concentration of 25%) were continuously added thereto to prepare an oxidation. The cuprous slurry (the first reduction treatment p is further stirred for 30 minutes in order to completely carry out the reduction reaction. Thereafter, pure water is added to the cuprous oxide slurry for repulping cleaning, thereby the amount of liquid Adjusted to 丨8 L, after which it was allowed to stand, and the cuprous oxide particles were precipitated, and the operation of removing the supernatant after 14 L of standing was repeated until the pH became 4.7 ^, and 8 L of heated pure water was added. , so that the total liquid amount is 12 L ' and the liquid temperature is maintained at a price, and the copper concentration is adjusted to 2 〇 rnol / L, thereby using it as a cleaning cuprous oxide slurry. Cleaning the cuprous oxide after adjusting the copper concentration In the slurry, 3. sub-phosphoric acid was added and stirred for 5 minutes. Again, water was added in such a manner that the copper concentration of the oxidized ferrous oxide aggregate was 2 〇 and the amount of liquid was adjusted. In the cleaning oxidized sub-steel slurry, 肼g of 肼 water σ substance is added. Further, the i 5 minute search was performed, and the reduction reaction το王进仃' and the copper particles were reduced and precipitated (second reduction treatment). [Comparative Example 4] The conditions shown in Table 1 below were used, and Example " The same way to obtain steel particles. I63139.doc 201244853 [I<] 2nd reduction reaction j mol (mol/Culmol) 1.56 1 1.20 1 0.98 0.78 4.16 3.30 1.56 0.87 坺 target 1 W逄1 ^ B 1 1 1 1 1 0.02 1 1 Total concentration of water-soluble substance added (mol/L) 卜<N inch CN cm' so <N 1 0.036 1 1 0.035 1 1 o.oi 1 〇<Ν Type 1 'NaCI NaNQ3 Ση Z 1 1 1 1 Filtration Difficulty First reduction reaction (CuO-Cu20) Ammonia water (mol/Culmol) 0.40 1 0.40 1 0.40 0.40 1 1 0.40 0.40 肼(mol/Culmol) __ 卜卜1 1 0.58 0.58 1 CuO formation NaOH j (mol/Culmol) 0.87 1 0.87 1 0.87 0.87 1 1 1 0.87 ^ Ammonia j (mol/Culmol) 0.89 1 0.89 1 0.89 0.89 1 1 1.72 0.89 Addition concentration of compound (mmoI/Culmol) 1 1 1 1 59.7 41.8 1 1 水溶液Chromium-containing aqueous solution temperature CC) Ό V〇V*J VO Vi Ό v-> Ό 1 30-80 1 30-80 Concentration (mol/ L) 卜 卜 rn rn rn r - ro Ο VO ο 卜 Example 1 | Example 2 1 Example 3 Example 4 Comparative Example 1 1 Comparative Example 2 1 Comparative Example 3 Comparative Example 4 -19- 163139.doc 201244853 [Evaluation] The amount of carbon contained in the copper particles obtained in the examples and the comparative examples was measured by the carbon analysis described above, and the phosphorus was measured by ICp (inductively coupled plasma) luminescence analysis. the amount. Further, the Dw and CV values of the copper particles obtained in the examples and the comparative examples were measured by image analysis. Further, with respect to the copper particles obtained in the examples and the comparative examples, the powder resistance values were measured by the following methods. Further, with respect to the copper particles obtained in the examples and the comparative examples, the slurry was prepared by the following method to measure the surface roughness of the film produced from the slurry. The results are shown in Table 2 below. Further, with respect to Example 丨 and Comparative Example j, and Example 3 and Comparative Example 2, the measurement of the volume change by thermomechanical analysis was measured by the following method. These results are shown in Figures 3(a) and (b). [Measurement of the powder resistance value] The powder resistance measurement system (Mitsubishi Chemical PD_41) and the resistivity meter (Mitsubishi Chemical MCP-T600) were used to measure the powder resistance value. A 15 g sample was placed in the probe cylinder and the probe unit was mounted to the PD-41. Using MCp_T600, the resistance was measured by applying a pressure of 4 Torr by a hydraulic jack. The powder resistance value was calculated from the measured resistance value and the sample thickness. [Measurement of Surface Roughness of Film Made of Slurry] The copper particles and solvent (95 g of terpineol and 5 g of ethylcellulose) obtained in the examples and the comparative examples, The slurry was prepared by mixing in a weight ratio of 丨:i. Using a mixer (Thinky, ARE_25〇), 163139.doc 201244853 the slurry was rotated at 2000 rpm for 45 seconds to perform pre-kneading. The slurry was then scoured in a three-roll mill (AIMEX (model), model RMZ-1). The gap between the rolls was set to 5 μm. The slurry obtained in the above manner was applied onto a glass substrate using a 30 μηι applicator (YOSHIMITSU SEIKI, model YR-1) to form a coating film. The coating film was dried at 80 ° C for 5 minutes. The surface roughness Ra and Rmax of the film obtained in the above manner were measured using a surface roughness measuring instrument (Tokyo Precision Co., Ltd., Surfcoml 30A). [Measurement of volume change by thermomechanical analysis] SEIKO EXSTAR 6000 manufactured by SEIKO Instrument Inc. was used. The sample was used to measure 0.5 g of copper particles to be measured in a mold, and pressurized by a press at a pressure of 1 ton/cm 2 to form particles. The sample was placed in a thermal analysis apparatus, and the length of the sample before the measurement was measured (the apparatus was automatically measured). The sample was pressed from the upper side with a pressure of 49 mN. The volume change was measured when the temperature was raised under the conditions of a gas atmosphere of 1% H2-N2 (150 mL/min) and a temperature rising rate of l〇°C /min. [Table 2] C amount (% by weight) P amount (PPm) D50 _ CV value (%) Powder resistance value (Ω-cm) Ra (μηι) Rmax (4) Example 1 0.005 <10 0.42 34.7 9.9E-03 0.135 1.147 Example 2 0.007 <10 0.87 33.2 7.2E-03 0.144 1.203 Example 3 0.006 <10 1.79 21.8 1.2E-03 0.379 3.311 Example 4 0.005 <10 3.76 12.1 7.8E-04 0.421 3.776 Comparative Example 1 0.007 0.2 wt% 0.62 45.1 3.8E+01 0.212 2.021 Comparative Example 2 0.005 0.2 wt% 1.80 38.3 5.0E+00 0.402 3.895 Comparative Example 3 0.005 470 1.76 55.2 6.2E-02 0.685 4.579 Comparative Example 4 0.006 <10 2.07 81.3 9.6 E-03 1.680 11.210 It is clear from the results shown in Table 2 that the copper particles obtained in the respective examples have a low carbon content and good dispersibility. Further, it can be seen that in each of the examples, 163139.doc •21 · 201244853 obtained copper particles having a low powder resistance value. Further, it is understood that the surface properties of the crucible formed by using the copper particles obtained in the respective examples are good. On the other hand, it is understood that the copper particles obtained in Comparative Examples 1 and 2 have a low carbon content, but they are less dispersible and aggregate than the copper particles of the examples. Further, from the results shown in Figs. 3(a) and 3(b), it is clear that the steel particles not containing p (the present invention) have higher heat shrinkage when compared with the same degree of particle diameter. Copper particles containing p (comparative). BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a scanning electron microscope image of copper particles obtained in Example 1. Fig. 2 is a scanning electron microscope image of the copper particles obtained in Comparative Example 2. @3(4) and (8) are graphs showing the results of measurement of volume change of the copper particles obtained in the examples and the comparative examples by thermomechanical analysis. 163139.doc •22-