以下，對本實施形態之預敷層用焊料組合物、及印刷配線基板之製造方法之實施形態進行說明。 [助焊劑組合物] 本實施形態之預敷層用焊料組合物係含有以下說明之助焊劑組合物、及以下說明之(D)焊料粉末者。 首先，對於本實施形態中使用之助焊劑組合物進行說明。 本實施形態中使用之助焊劑組合物係含有以下說明之(A)松香系樹脂、(B)活性劑及(C)溶劑者。 [(A)成分] 作為本實施形態中所使用之(A)松香系樹脂，可列舉：松香類及松香系改性樹脂。作為松香類，可列舉：松脂膠、木松香、妥爾油松香、歧化松香、聚合松香、氫化松香及該等之衍生物等。作為松香系改性樹脂，可列舉：可成為狄爾斯-阿爾德反應(Diels-Alder reaction)之反應成分之上述松香類之不飽和有機酸改性樹脂((甲基)丙烯酸等脂肪族之不飽和一元酸、反丁烯二酸、順丁烯二酸等α,β-不飽和羧酸等脂肪族不飽和二元酸、桂皮酸等具有芳香族環之不飽和羧酸等之改性樹脂)及該等改性物等之松香酸、以及以該等改性物作為主成分者等。該等松香系樹脂可單獨使用1種，亦可將2種以上混合而使用。 上述(A)成分之調配量相對於助焊劑組合物100質量%，較佳為30質量%以上且70質量%以下，更佳為35質量%以上且60質量%以下。若(A)成分之調配量為上述下限以上，則可將附焊料之焊墊之銅箔面之氧化膜去除而於其表面容易地濕潤熔融焊料。又，若(A)成分之調配量為上述上限以下，則可充分地抑制助焊劑殘渣量。 [(B)成分] 本實施形態中所使用之(B)活性劑需含有(B1)N,N,N',N'-四(2-羥基丙基)乙二胺。於不含該(B1)成分之情形時，無法兼顧焊料潤濕性與保存穩定性。 又，就焊料潤濕性之提高之觀點而言，該(B1)成分之調配量相對於助焊劑組合物100質量%，較佳為1質量%以上且35質量%以下，更佳為5質量%以上且30質量%以下，尤佳為12質量%以上且25質量%以下，最佳為15質量%以上且20質量%以下。 於本實施形態中，較佳為上述(B)成分進而含有(B2)鹵素系活性劑。藉由該(B2)成分，可進而提高焊料潤濕性。然而，就焊料組合物中之鹵素量之降低之觀點而言，該(B2)成分之調配量相對於助焊劑組合物100質量%，較佳為0.01質量%以上且3質量%以下，更佳為0.1質量%以上且1質量%以下。 作為上述(B2)成分，可為如氯化物、溴化物、氟化物般藉由氯、溴、氟之各單獨元素之共價鍵之化合物，亦可為具有氯、溴及氟之任意之兩個或全部之各自之共價鍵之化合物。關於該等化合物，為了提高對於水性溶劑之溶解性，例如較佳為如鹵化醇或鹵化羧基化合物般具有羥基或羧基等極性基。作為鹵化醇，例如可列舉：2,3-二溴丙醇、2,3-二溴丁二醇、反式-2,3-二溴-2-丁烯-1,4-二醇、1,4-二溴-2-丁醇、及三溴新戊醇等溴化醇、1,3-二氯-2-丙醇、及1,4-二氯-2-丁醇等氯化醇、3-氟鄰苯二酚等氟化醇、以及其他類似於該等之化合物。作為鹵化羧基化合物，可列舉：2-碘苯甲酸、3-碘苯甲酸、2-碘丙酸、5-碘水楊酸、及5-碘鄰胺苯甲酸等碘化羧基化合物、2-氯苯甲酸、及3-氯丙酸等氯化羧基化合物、2,3-二溴丙酸、2,3-二溴丁二酸、及2-溴苯甲酸等溴化羧基化合物、以及其他類似於該等之化合物。該等中，就焊料潤濕性之觀點而言，較佳為碘化羧基化合物，更佳為2-碘苯甲酸、3-碘苯甲酸。再者，該等可單獨使用1種，亦可將2種以上混合而使用。 於本實施形態中，上述(B)成分亦可進而含有(B3)有機酸。藉由該(B3)成分，可提高活性作用。於使用該(B3)成分之情形時，其調配量相對於助焊劑組合物100質量%，較佳為0.1質量%以上且10質量%以下，更佳為0.5質量%以上且7質量%以下，尤佳為1質量%以上且5質量%以下。 作為上述(B3)成分，除單羧酸、二羧酸等以外，亦可列舉其他有機酸。 作為單羧酸，可列舉：甲酸、乙酸、丙酸、丁酸、戊酸、己酸、庚酸、癸酸、月桂酸、肉豆蔻酸、十五酸、棕櫚酸、十七酸、硬脂酸、結核硬脂酸、花生酸、山萮酸、二十四碳酸、及乙醇酸等。 作為二羧酸，可列舉：草酸、丙二酸、丁二酸、戊二酸、己二酸、庚二酸、辛二酸、壬二酸、癸二酸、反丁烯二酸、順丁烯二酸、酒石酸、及二乙醇酸等。 作為其他有機酸，可列舉：二聚酸、乙醯丙酸、乳酸、丙烯酸、苯甲酸、水楊酸、大茴香酸、檸檬酸、及吡啶甲酸等。 上述(B)成分亦可於可達成本發明之目的之範圍內含有上述(B1)成分、上述(B2)成分及上述(B3)成分以外之活性劑((B4)成分)。作為該(B4)成分，例如可列舉：上述(B1)成分以外之胺系活性劑等。 上述(B)成分之調配量相對於助焊劑組合物100質量%，較佳為1質量%以上且40質量%以下，更佳為5質量%以上且35質量%以下，尤佳為12質量%以上且30質量%以下，最佳為15質量%以上且25質量%以下。若(B)成分之調配量為上述下限以上，則可確保充分之焊料潤濕性。又，若(B)成分之調配量為上述上限以下，則可確保保存穩定性。 [(C)成分] 作為本實施形態中所使用之(C)溶劑，可適宜使用公知之溶劑。作為此種溶劑，較佳為使用沸點170℃以上之溶劑。 作為此種溶劑，例如可列舉：二乙二醇、二丙二醇、三乙二醇、己二醇、己基二乙二醇、1,5-戊二醇、甲基卡必醇、丁基卡必醇、2-乙基己基二乙二醇、辛二醇、苯乙二醇、二乙二醇單己醚、四乙二醇二甲醚、及順丁烯二酸二丁酯等。該等溶劑可單獨使用1種，亦可將2種以上混合而使用。 上述(C)成分之調配量相對於助焊劑組合物100質量%，較佳為10質量%以上且60質量%以下，更佳為15質量%以上且40質量%以下，尤佳為20質量%以上且30質量%以下。若溶劑之調配量為上述範圍內，則可將所獲得之焊料組合物之黏度適宜調整為適當之範圍。 於本實施形態之助焊劑組合物中，就印刷性等觀點而言，亦可進而含有觸變劑。作為此處所使用之觸變劑，可列舉：氫化蓖麻油、聚胺類、聚醯胺類、雙醯胺類、二亞苄基山梨糖醇、高嶺土、膠體二氧化矽、有機膨潤土、玻璃料等。該等觸變劑可單獨使用1種，亦可將2種以上混合而使用。 於使用上述觸變劑之情形時，其調配量相對於助焊劑組合物100質量%，較佳為1質量%以上且15質量%以下，更佳為5質量%以上且10質量%以下。若調配量為上述下限以上，則可獲得充分之觸變性，可充分地抑制塌邊。又，若調配量為上述上限以下，則不會觸變性過高而導致印刷不良。 [其他成分] 於本實施形態中所使用之助焊劑組合物中，除上述(A)成分、上述(B)成分、上述(C)成分及上述觸變劑以外，視需要可添加其他添加劑、進而其他樹脂。作為其他添加劑，可列舉：消泡劑、抗氧化劑、改質劑、消光劑、發泡劑、硬化促進劑等。作為其他樹脂，可列舉：環氧樹脂、丙烯酸樹脂、胺基甲酸酯樹脂、聚醯亞胺樹脂等。 [預敷層用焊料組合物] 其次，對本實施形態之預敷層用焊料組合物進行說明。本實施形態之預敷層用焊料組合物係含有上述助焊劑組合物、及以下說明之(D)焊料粉末者。 上述助焊劑組合物之調配量相對於焊料組合物100質量%，較佳為10質量%以上且50質量%以下，更佳為15質量%以上且40質量%以下，尤佳為20質量%以上且35質量%以下。只要助焊劑組合物之調配量為10質量%以上(焊料粉末之調配量為90質量%以下)，則作為黏合劑之助焊劑組合物充足，因此可容易地將助焊劑組合物與焊料粉末進行混合。又，只要助焊劑組合物之調配量為50質量%以下(焊料粉末之調配量為50質量%以上)，則於使用所獲得之焊料組合物之情形時，可形成均勻之預敷層。 本實施形態之預敷層用焊料組合物之焊料潤濕性優異，且具有充分之保存穩定性。並且，即便為可對應於印刷配線基板之無鹵素型之預敷層用焊料組合物，亦可確保與使用鹵素系之活性劑之情形同等之焊料潤濕性，故而可尤佳地用作低鹵素之預敷層用焊料組合物。 低鹵素之預敷層用焊料組合物較佳為氯濃度為900質量ppm以下，溴濃度為900質量ppm以下，碘濃度為900質量ppm以下，且鹵素濃度為1500質量ppm以下者。再者，作為鹵素，可列舉：氟、氯、溴及碘等。 再者，預敷層用焊料組合物中之氯濃度、溴濃度及鹵素濃度可依據JEITA ET-7304A中記載之方法而測定。又，簡單地說，可由預敷層用焊料組合物之調配成分及其調配量而算出。 [(D)成分] 本實施形態中所使用之(D)焊料粉末較佳為僅由無鉛焊料粉末構成，亦可為有鉛之焊料粉末。作為該焊料粉末中之焊料合金，較佳為以錫(Sn)作為主成分之合金。又，作為該合金之第二元素，可列舉：銀(Ag)、銅(Cu)、鋅(Zn)、鉍(Bi)、銦(In)及銻(Sb)等。進而，於該合金中，亦可視需要添加其他元素(第三元素以後)。作為其他元素，可列舉：銅、銀、鉍、銦、銻、鈷(Co)、鉻(Cr)、鎳(Ni)、鍺(Ge)、鐵(Fe)及鋁(Al)等。 此處，所謂無鉛焊料粉末，係指不添加鉛之焊料金屬或合金之粉末。然而，容許於無鉛焊料粉末中存在鉛作為不可避免之雜質，但於該情形時，鉛之量較佳為100質量ppm以下。 作為無鉛之焊料粉末，具體而言，可列舉：Sn-Ag、Sn-Ag-Cu、Sn-Cu、Sn-Ag-Bi、Sn-Bi、Sn-Ag-Cu-Bi、Sn-Sb、Sn-Zn-Bi、Sn-Zn、Sn-Zn-Al、Sn-Zn-Bi-Al、Sn-Ag-Bi-In、Sn-Ag-Cu-Bi-In-Sb、In-Ag等。該等中，就焊料接合之強度之觀點而言，可較佳地使用Sn-Ag-Cu系之焊料合金。並且，Sn-Ag-Cu系之焊料之熔點通常為200℃以上且250℃以下。再者，於Sn-Ag-Cu系之焊料中，銀含量較低之系統之焊料之熔點為210℃以上且250℃以下。又，於此種焊料合金中，銀含量通常為4質量%以下，銅之含量通常為1質量%以下。又，就低熔點之觀點而言，可較佳地使用Sn-Bi系之焊料合金。並且，Sn-Bi系之焊料之熔點通常為130℃以上且170℃以下。 於本實施形態中，上述(D)成分中之粒徑為5 μm以下之粒子需為40體積%以上。於不滿足該條件之情形時，焊料潤濕性變得不充分。再者，焊料粉末之粒徑分佈例如可藉由動態光散射式之粒徑測定裝置(COULTER公司製造，「雷射繞射式粒子尺寸分析儀LS130」)進行測定。並且，由該粒徑分佈，可算出(D)成分中之粒徑為5 μm以下之粒子之比率([(D)成分中之粒徑為5 μm以下之粒子之體積/(D)成分之總體積]×100)。 又，作為將(D)成分中之粒徑為5 μm以下之粒子調整為上述之範圍之方法，可列舉如下之方法。 例如，可藉由變更離心粉末製造裝置之條件(原料供給速度、焊料合金之組成)而進行調整。又，可藉由將兩種以上之不同之粒徑分佈之焊料粉末以特定比率進行混合而調整。 [焊料組合物之製造方法] 本實施形態之焊料組合物可藉由將上述說明之助焊劑組合物與上述說明之(D)焊料粉末以上述特定之比率調配，並進行攪拌混合而製造。 [印刷配線基板之製造方法] 其次，對本實施形態之印刷配線基板之製造方法進行說明。本實施形態之印刷配線基板之製造方法係使用上述之本實施形態之預敷層用焊料組合物之方法，且具備：塗佈步驟，其係於上述印刷配線基板之電極上印刷上述焊料組合物；及預敷層形成步驟，其係對印刷步驟後之上述印刷配線基板進行加熱，使上述焊料組合物中之焊料粉末熔融，而於上述電極上形成焊料覆膜。 於塗佈步驟中，於印刷配線基板之電極上，塗佈預敷層用焊料組合物。 作為此處所使用之塗佈裝置，可列舉：網版印刷機、金屬遮罩印刷機、分注器等。 塗佈膜之厚度通常為20 μm以上且50 μm以下。 於預敷層形成步驟中，藉由對塗佈步驟後之印刷配線基板進行加熱，使焊料組合物中之焊料粉末熔融，而於電極上形成焊料覆膜。 作為對印刷配線基板進行加熱之裝置，可使用回焊爐。再者，作為回焊爐，可列舉：空氣回焊裝置、真空回焊裝置、甲酸回焊裝置、及電漿回焊裝置等。該等中，就裝置設備之成本之觀點而言，較佳為空氣回焊裝置。 回焊條件只要根據焊料之熔點而適宜設定即可。例如，於使用Sn-Ag-Cu系之焊料合金之情形時，預熱溫度較佳為140℃以上且200℃以下，更佳為150℃以上且160℃以下。預熱時間較佳為60秒以上且120秒以下。峰值溫度較佳為230℃以上且270℃以下，更佳為240℃以上且255℃以下。又，220℃以上之溫度之保持時間較佳為20秒以上且60秒以下。實施例 其次，藉由實施例及比較例對本發明進行更詳細之說明，但本發明並不受該等例任何限定。再者，將實施例及比較例中所使用之材料示於以下。 ((A)成分) 松香系樹脂A：氫化酸改性松香、商品名「Pinecrystal KE-604」、荒川化學工業公司製造 松香系樹脂B：氫化松香酯、商品名「M-HDR」、丸善油化商事公司製造 ((B1)成分) 胺系活性劑A：N,N,N',N'-四(2-羥基丙基)乙二胺 ((B2)成分) 鹵素系活性劑A：2-碘苯甲酸 鹵素系活性劑B：二溴丁烯二醇 ((B3)成分) 有機酸A：辛二酸 有機酸B：丙二酸 ((B4)成分) 胺系活性劑B：十八烷基胺 ((C)成分) 溶劑：己基二乙二醇、日本乳化劑公司製造 ((D)成分) 焊料粉末A：粒徑分佈2～6 μm(平均粒徑4 μm)、焊料熔點217～220℃、焊料組成Sn-Ag3.0-Cu0.5 焊料粉末B：粒徑分佈1～12 μm(平均粒徑6 μm)、焊料熔點217～220℃、焊料組成Sn-Ag3.0-Cu0.5 (其他成分) 觸變劑：氫化蓖麻油、商品名「HIMAKOU」、KF Trading公司製造 [實施例1] 作為助焊劑組合物，藉由調配松香系樹脂A40質量%、松香系樹脂B10質量%、胺系活性劑A14質量%、有機酸A2.6質量%、有機酸B0.6質量%、鹵素系活性劑A0.5質量%、鹵素系活性劑B0.3質量%、觸變劑8質量%、及溶劑24質量%，並適宜混合，而獲得助焊劑組合物。 又，藉由調配所獲得之助焊劑組合物30質量%、焊料粉末A35質量%、及焊料粉末B35質量%(合計為100質量%)並適宜混合，而製備焊料組合物。 [實施例2～8及比較例1～6] 依據表1所示之組成而調配各材料，除此以外，以與實施例1同樣之方式，獲得助焊劑組合物及焊料組合物。 ＜焊料組合物之評價＞ 以如下之方法進行焊料組合物之評價(焊料潤濕性、助焊劑殘渣洗淨性、保存穩定性)。將所獲得之結果示於表1。 又，將焊料組合物之物性值(5 μm以下之焊料粉末之比率(單位：體積%)、焊料粉末之平均粒徑(單位：μm)、以及焊料組合物中之溴濃度、碘濃度及鹵素濃度(單位：質量ppm，由調配量得到之算出值))示於表1。 (1)焊料潤濕性 按照下述之基板製作條件，將焊料組合物印刷至基板，實施回焊處理，而製作焊料潤濕性之評價基板。 基板：FR-4基板(焊料潤濕性及助焊劑殘渣洗淨性之評價基板) 阻焊劑開口直徑：400～500 μm 表面處理：銅電極(水溶性助焊劑塗佈) 塗佈方法：網版印刷 金屬遮罩厚度：30 μm 遮罩開口直徑：阻焊劑開口直徑之70% 刮刀：金屬刮刀 回焊爐：Tamura製作所公司製造之「TNP25-538EM」 回焊時氧濃度：100 ppm以下 回焊分佈：圖1 並且，將所獲得之評價基板之預敷層區域整體利用顯微鏡進行觀察，依據下述之基準而評價焊料潤濕性。 A：針孔狀之不潤濕或抗蝕劑時之不潤濕之產生為5個以下。 B：針孔狀之不潤濕或抗蝕劑時之不潤濕之產生為6個以上且10個以下。 C：針孔狀之不潤濕或抗蝕劑時之不潤濕之產生為11個以上且19個以下。 D：針孔狀不潤濕或抗蝕劑時之不潤濕之產生為20個以上。 (2)助焊劑殘渣洗淨性 利用與上述(1)焊料潤濕性之評價相同之方法，製作評價基板，於下述之條件下將該評價基板之助焊劑殘渣洗淨。 洗淨液：花王公司製造之「CLEANTHROUGH 750HS」 浸漬洗淨時間：120秒 並且，藉由目視而觀察洗淨後之評價基板，並依據下述之基準，評價助焊劑殘渣洗淨性。 A：無助焊劑殘渣之洗淨殘留。 C：有助焊劑殘渣之洗淨殘留。 (3)保存穩定性 將焊料組合物填充至聚乙烯容器中，並投入至溫度30℃之恆溫槽中，保管1個月。使保管1個月後之焊料組合物恢復至室溫後，使用鏟子攪拌1分鐘，觀察性狀。並且，依據下述之基準而評價保存穩定性。 A：焊料組合物為膏狀，且為無性狀變化之狀態。 B：焊料組合物保持膏狀，但為確認到焊料粉末之凝聚之狀態。 C：焊料組合物未保持膏狀而為無平滑性之狀態。 [表1]
如由表1所示之結果所明確，本發明之預敷層用焊料組合物(實施例1～8)之焊料潤濕性、助焊劑殘渣洗淨性及保存穩定性之結果均為良好，確認到焊料潤濕性優異，且具有充分之保存穩定性。Hereinafter, embodiments of the solder composition for a pre-coat layer and a method for producing a printed wiring board according to the present embodiment will be described. [Flux composition] The solder composition for a pre-coat layer of the present embodiment contains the flux composition described below and (D) the solder powder described below. First, the flux composition used in the present embodiment will be described. The flux composition used in the present embodiment contains (A) a rosin-based resin, (B) an active agent, and (C) a solvent described below. [Component (A)] The rosin-based resin (A) used in the present embodiment may, for example, be a rosin-based or rosin-based modified resin. Examples of the rosin include rosin gum, wood rosin, tall oil rosin, disproportionated rosin, polymerized rosin, hydrogenated rosin, and derivatives thereof. The rosin-based modified resin may be an unsaturated organic acid-modified resin (an aliphatic group such as (meth)acrylic acid) which is a reaction component of a Diels-Alder reaction. Modification of unsaturated unsaturated carboxylic acid such as unsaturated monobasic acid, fumaric acid or maleic acid, such as an aliphatic unsaturated dibasic acid such as α,β-unsaturated carboxylic acid or cinnamic acid Resin), rosin acid such as these modified substances, and the like, and the like as the main component. These rosin-based resins may be used singly or in combination of two or more. The amount of the component (A) to be added is preferably 30% by mass or more and 70% by mass or less, and more preferably 35% by mass or more and 60% by mass or less based on 100% by mass of the flux composition. When the amount of the component (A) is at least the above lower limit, the oxide film on the copper foil surface of the solder pad can be removed, and the molten solder can be easily wetted on the surface. In addition, when the amount of the component (A) is less than or equal to the above upper limit, the amount of flux residue can be sufficiently suppressed. [Component (B)] The (B) active agent used in the present embodiment is required to contain (B1) N,N,N',N'-tetrakis(2-hydroxypropyl)ethylenediamine. In the case where the component (B1) is not contained, solder wettability and storage stability cannot be achieved. In addition, the amount of the component (B1) is preferably 1% by mass or more and 35% by mass or less, more preferably 5% by mass based on 100% by mass of the flux composition from the viewpoint of improvement in solder wettability. % or more and 30% by mass or less, particularly preferably 12% by mass or more and 25% by mass or less, and most preferably 15% by mass or more and 20% by mass or less. In the present embodiment, it is preferred that the component (B) further contains (B2) a halogen-based active agent. Further, the solder wettability can be further improved by the component (B2). However, from the viewpoint of the reduction in the amount of halogen in the solder composition, the amount of the component (B2) is preferably 0.01% by mass or more and 3% by mass or less, more preferably 100% by mass based on the mass of the flux composition. It is 0.1% by mass or more and 1% by mass or less. The component (B2) may be a compound having a covalent bond such as a chloride, a bromide or a fluoride by a separate element of chlorine, bromine or fluorine, or may be any of chlorine, bromine and fluorine. Compounds of one or all of their respective covalent bonds. These compounds have a polar group such as a hydroxyl group or a carboxyl group as in the case of a halogenated alcohol or a halogenated carboxyl compound, for example, in order to improve the solubility in an aqueous solvent. Examples of the halogenated alcohol include 2,3-dibromopropanol, 2,3-dibromobutanediol, trans-2,3-dibromo-2-butene-1,4-diol, and 1 , 4-dibromo-2-butanol, and brominated alcohols such as tribromoneopentyl alcohol, 1,3-dichloro-2-propanol, and chlorinated alcohol such as 1,4-dichloro-2-butanol , fluorinated alcohols such as 3-fluorocatechol, and other compounds similar to these. Examples of the halogenated carboxyl compound include iodinated carboxyl compounds such as 2-iodobenzoic acid, 3-iodobenzoic acid, 2-iodopropionic acid, 5-iodosalicylic acid, and 5-iodo-o-amine benzoic acid, and 2-chloro a carboxylic acid carboxyl compound such as benzoic acid or 3-chloropropionic acid, a brominated carboxyl compound such as 2,3-dibromopropionic acid, 2,3-dibromosuccinic acid, or 2-bromobenzoic acid, and the like These compounds. Among these, from the viewpoint of solder wettability, a iodinated carboxyl compound is preferred, and 2-iodobenzoic acid or 3-iodobenzoic acid is more preferred. In addition, these may be used alone or in combination of two or more. In the present embodiment, the component (B) may further contain (B3) an organic acid. By the component (B3), the activity can be enhanced. When the component (B3) is used, the amount thereof is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.5% by mass or more and 7% by mass or less based on 100% by mass of the flux composition. It is particularly preferably 1% by mass or more and 5% by mass or less. As the component (B3), other organic acids may be mentioned in addition to the monocarboxylic acid, the dicarboxylic acid, and the like. Examples of the monocarboxylic acid include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptanoic acid, citric acid, lauric acid, myristic acid, pentadecanoic acid, palmitic acid, heptadecanoic acid, and stearic acid. Acid, tuberculous stearic acid, arachidic acid, behenic acid, 24 carbonic acid, and glycolic acid. Examples of the dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, fumaric acid, and cis-butane. Alkenoic acid, tartaric acid, and diglycolic acid. Examples of the other organic acid include dimer acid, acetopropionic acid, lactic acid, acrylic acid, benzoic acid, salicylic acid, anisic acid, citric acid, and picolinic acid. The component (B) may contain the above-mentioned (B1) component, the above-mentioned (B2) component, and the above-mentioned (B3) component, and the active agent ((B4) component) in the range of the objective of the invention. Examples of the component (B4) include an amine-based active agent other than the component (B1). The amount of the component (B) to be added is preferably 1% by mass or more and 40% by mass or less, more preferably 5% by mass or more and 35% by mass or less, and particularly preferably 12% by mass based on 100% by mass of the flux composition. The above is 30% by mass or less, and preferably 15% by mass or more and 25% by mass or less. When the compounding amount of the component (B) is at least the above lower limit, sufficient solder wettability can be ensured. Further, when the blending amount of the component (B) is at most the above upper limit, storage stability can be ensured. [Component (C)] As the solvent (C) used in the present embodiment, a known solvent can be suitably used. As such a solvent, a solvent having a boiling point of 170 ° C or higher is preferably used. Examples of such a solvent include diethylene glycol, dipropylene glycol, triethylene glycol, hexanediol, hexyl diethylene glycol, 1,5-pentanediol, methyl carbitol, and butyl carbene. Alcohol, 2-ethylhexyl diethylene glycol, octanediol, phenethylene glycol, diethylene glycol monohexyl ether, tetraethylene glycol dimethyl ether, and dibutyl maleate. These solvents may be used alone or in combination of two or more. The amount of the component (C) to be added is preferably 10% by mass or more and 60% by mass or less, more preferably 15% by mass or more and 40% by mass or less, and particularly preferably 20% by mass or less based on 100% by mass of the flux composition. The above is 30% by mass or less. If the amount of the solvent is within the above range, the viscosity of the obtained solder composition can be appropriately adjusted to an appropriate range. In the flux composition of the present embodiment, a thixotropic agent may be further contained from the viewpoint of printability and the like. Examples of the thixotropic agent used herein include hydrogenated castor oil, polyamines, polyamines, bis-amines, dibenzylidene sorbitol, kaolin, colloidal cerium oxide, organic bentonite, and glass frit. Wait. These thixotropic agents may be used alone or in combination of two or more. In the case of using the thixotropic agent, the amount thereof is preferably 1% by mass or more and 15% by mass or less, more preferably 5% by mass or more and 10% by mass or less based on 100% by mass of the flux composition. When the compounding amount is at least the above lower limit, sufficient thixotropy can be obtained, and sag can be sufficiently suppressed. Moreover, when the compounding amount is less than or equal to the above upper limit, the thixotropy is not excessively high and the printing failure is caused. [Other components] In the flux composition used in the present embodiment, in addition to the component (A), the component (B), the component (C), and the thixotropic agent, other additives may be added as needed. And other resins. Examples of other additives include antifoaming agents, antioxidants, modifiers, matting agents, foaming agents, and curing accelerators. Examples of the other resin include an epoxy resin, an acrylic resin, a urethane resin, and a polyimide resin. [Solder Composition for Precoat Layer] Next, the solder composition for a precoat layer of the present embodiment will be described. The solder composition for a pre-coating layer of the present embodiment contains the flux composition described above and (D) the solder powder described below. The amount of the flux composition to be added is preferably 10% by mass or more and 50% by mass or less, more preferably 15% by mass or more and 40% by mass or less, and particularly preferably 20% by mass or more based on 100% by mass of the solder composition. And 35% by mass or less. When the amount of the flux composition is 10% by mass or more (the amount of the solder powder is 90% by mass or less), the flux composition as a binder is sufficient, so that the flux composition and the solder powder can be easily performed. mixing. In addition, as long as the blending amount of the flux composition is 50% by mass or less (the amount of the solder powder is 50% by mass or more), a uniform precoat layer can be formed when the obtained solder composition is used. The solder composition for a pre-coat layer of the present embodiment is excellent in solder wettability and has sufficient storage stability. In addition, even if it is a halogen-free solder composition for a pre-coat layer which can be used for a printed wiring board, solder wettability equivalent to that of a halogen-based active agent can be secured, so that it can be used particularly preferably. A solder composition for a halogen precoat layer. The solder composition for a low-halogen pre-coating layer preferably has a chlorine concentration of 900 ppm by mass or less, a bromine concentration of 900 ppm by mass or less, an iodine concentration of 900 ppm by mass or less, and a halogen concentration of 1,500 ppm by mass or less. Further, examples of the halogen include fluorine, chlorine, bromine, and iodine. Further, the chlorine concentration, the bromine concentration and the halogen concentration in the solder composition for the precoat layer can be measured in accordance with the method described in JEITA ET-7304A. Moreover, simply, it can be calculated from the compounding component of the solder composition for a precoat layer, and the compounding amount. [(D) Component] The (D) solder powder used in the present embodiment is preferably composed of only lead-free solder powder, and may be lead-containing solder powder. As the solder alloy in the solder powder, an alloy containing tin (Sn) as a main component is preferable. Further, examples of the second element of the alloy include silver (Ag), copper (Cu), zinc (Zn), bismuth (Bi), indium (In), and antimony (Sb). Further, in the alloy, other elements (after the third element) may be added as needed. Examples of other elements include copper, silver, bismuth, indium, antimony, cobalt (Co), chromium (Cr), nickel (Ni), germanium (Ge), iron (Fe), and aluminum (Al). Here, the lead-free solder powder refers to a powder of a solder metal or alloy to which no lead is added. However, the presence of lead in the lead-free solder powder is an unavoidable impurity, but in this case, the amount of lead is preferably 100 ppm by mass or less. Specific examples of the lead-free solder powder include Sn-Ag, Sn-Ag-Cu, Sn-Cu, Sn-Ag-Bi, Sn-Bi, Sn-Ag-Cu-Bi, Sn-Sb, and Sn. -Zn-Bi, Sn-Zn, Sn-Zn-Al, Sn-Zn-Bi-Al, Sn-Ag-Bi-In, Sn-Ag-Cu-Bi-In-Sb, In-Ag, and the like. Among these, a Sn-Ag-Cu-based solder alloy can be preferably used from the viewpoint of the strength of the solder joint. Further, the melting point of the Sn-Ag-Cu solder is usually 200 ° C or more and 250 ° C or less. Further, in the Sn-Ag-Cu solder, the melting point of the solder having a low silver content is 210 ° C or more and 250 ° C or less. Further, in such a solder alloy, the content of silver is usually 4% by mass or less, and the content of copper is usually 1% by mass or less. Further, from the viewpoint of a low melting point, a Sn-Bi-based solder alloy can be preferably used. Further, the Sn-Bi solder has a melting point of usually 130 ° C or more and 170 ° C or less. In the present embodiment, the particles having a particle diameter of 5 μm or less in the component (D) need to be 40% by volume or more. When the condition is not satisfied, the solder wettability becomes insufficient. Further, the particle size distribution of the solder powder can be measured, for example, by a dynamic light scattering type particle size measuring device ("Rain Drilling Particle Size Analyzer LS130" manufactured by COULTER Co., Ltd.). Further, from the particle size distribution, the ratio of the particles having a particle diameter of 5 μm or less in the component (D) (the volume of the particles having a particle diameter of 5 μm or less in the component (D)/(D) component can be calculated. Total volume] × 100). In addition, as a method of adjusting the particle diameter of 5 micrometers or less in (D) component to the said range, the following methods are mentioned. For example, the adjustment can be made by changing the conditions of the centrifugal powder manufacturing apparatus (feeding speed of the raw material, composition of the solder alloy). Further, it can be adjusted by mixing two or more different sizes of solder powders at a specific ratio. [Manufacturing Method of Solder Composition] The solder composition of the present embodiment can be produced by blending the above-described flux composition and the above-described (D) solder powder in the above specific ratio, and stirring and mixing the same. [Manufacturing Method of Printed Wiring Substrate] Next, a method of manufacturing the printed wiring board of the present embodiment will be described. The method for producing a printed wiring board according to the present embodiment is the method of using the solder composition for a pre-coating layer according to the above-described embodiment, and includes a coating step of printing the solder composition on an electrode of the printed wiring board. And a pre-coating layer forming step of heating the printed wiring board after the printing step to melt the solder powder in the solder composition to form a solder film on the electrode. In the coating step, a solder composition for a pre-coat layer is applied onto the electrode of the printed wiring board. Examples of the coating device used herein include a screen printing machine, a metal mask printing machine, a dispenser, and the like. The thickness of the coating film is usually 20 μm or more and 50 μm or less. In the precoat layer forming step, the solder powder in the solder composition is melted by heating the printed wiring substrate after the coating step to form a solder film on the electrode. As a device for heating the printed wiring board, a reflow furnace can be used. Further, examples of the reflow furnace include an air reflow device, a vacuum reflow device, a formic acid reflow device, and a plasma reflow device. Among these, an air reflow device is preferred from the viewpoint of the cost of the device. The reflow conditions may be appropriately set depending on the melting point of the solder. For example, in the case of using a Sn-Ag-Cu-based solder alloy, the preheating temperature is preferably 140 ° C or more and 200 ° C or less, more preferably 150 ° C or more and 160 ° C or less. The preheating time is preferably 60 seconds or more and 120 seconds or less. The peak temperature is preferably 230 ° C or more and 270 ° C or less, more preferably 240 ° C or more and 255 ° C or less. Further, the holding time of the temperature of 220 ° C or higher is preferably 20 seconds or longer and 60 seconds or shorter. EXAMPLES Next, the present invention will be described in more detail by way of examples and comparative examples, but the invention is not limited by the examples. Further, the materials used in the examples and comparative examples are shown below. (Component (A)) Rosin-based resin A: Hydrogenated acid-modified rosin, trade name "Pinecrystal KE-604", rosin resin B manufactured by Arakawa Chemical Industries Co., Ltd.: hydrogenated rosin ester, trade name "M-HDR", Maruzen oil Manufactured by the company (B1) Amine-based active agent A: N, N, N', N'-tetrakis (2-hydroxypropyl) ethylenediamine (component (B2)) Halogen-based active agent A: 2 -iodobenzoic acid halogen-based active agent B: dibromobutenediol (component (B3)) organic acid A: suberic acid organic acid B: malonic acid (component (B4)) amine-based active agent B: eighteen Alkylamine (component (C)) Solvent: hexyl diethylene glycol, manufactured by Japan Emulsifier Co., Ltd. ((D) component Solder powder A: particle size distribution 2 to 6 μm (average particle size 4 μm), solder melting point 217 ~220 ° C, solder composition Sn-Ag3.0-Cu0.5 solder powder B: particle size distribution 1 ~ 12 μm (average particle size 6 μm), solder melting point 217 ~ 220 ° C, solder composition Sn-Ag3.0-Cu0 .5 (Other components) Thixotropic agent: hydrogenated castor oil, trade name "HIMAKOU", manufactured by KF Trading Co., Ltd. [Example 1] As a flux composition, by blending rosin-based resin A 40% by mass, rosin-based resin B10 mass %, amine active agent A14 % by mass, organic acid A2.6% by mass, organic acid B 0.6% by mass, halogen-based active agent A 0.5% by mass, halogen-based active agent B 0.3% by mass, thixotropic agent 8% by mass, and solvent 24 mass %, and suitably mixed to obtain a flux composition. Moreover, the solder composition was prepared by blending 30% by mass of the flux composition, 35% by mass of the solder powder A, and 35% by mass of the solder powder B (total amount of 100% by mass). [Examples 2 to 8 and Comparative Examples 1 to 6] A flux composition and a solder composition were obtained in the same manner as in Example 1 except that the materials were blended according to the compositions shown in Table 1. <Evaluation of Solder Composition> The solder composition was evaluated by the following method (solder wettability, flux residue cleanability, storage stability). The results obtained are shown in Table 1. Further, the physical property value of the solder composition (the ratio of the solder powder (unit: vol%) of 5 μm or less, the average particle diameter (unit: μm) of the solder powder, and the bromine concentration, iodine concentration, and halogen in the solder composition) The concentration (unit: mass ppm, calculated from the blended amount) is shown in Table 1. (1) Solder Wetability The solder composition was printed on a substrate according to the following substrate production conditions, and a reflow process was performed to prepare a solder wettability evaluation substrate. Substrate: FR-4 substrate (evaluation of solder wettability and flux residue evaluation) Solder resist opening diameter: 400 to 500 μm Surface treatment: copper electrode (water-soluble flux coating) Coating method: screen Printed metal mask thickness: 30 μm Mask opening diameter: 70% of solder resist opening diameter Scraper: Metal scraper reflow oven: "TNP25-538EM" manufactured by Tamura Manufacturing Co., Ltd. Oxygen concentration during reflow: Reflow distribution below 100 ppm Fig. 1 Further, the entire pre-coating region of the obtained evaluation substrate was observed with a microscope, and the solder wettability was evaluated in accordance with the following criteria. A: The number of non-wetting of the pinhole-like non-wetting or resist is 5 or less. B: The occurrence of non-wetting in the case of pinhole-like non-wetting or resist is 6 or more and 10 or less. C: The generation of non-wetting in the form of pinholes or the resist is 11 or more and 19 or less. D: 20 or more generations of non-wetting in the case of pinhole-like non-wetting or resist. (2) Flux residue cleaning property The evaluation substrate was produced by the same method as the above (1) solder wettability evaluation, and the flux residue of the evaluation substrate was washed under the following conditions. Washing liquid: "CLEANTHROUGH 750HS" manufactured by Kao Corporation The immersion washing time was 120 seconds, and the washed evaluation substrate was observed by visual observation, and the flux residue cleanability was evaluated based on the following criteria. A: Washing residue of fluxless residue. C: It helps to wash the residue of the flux residue. (3) Storage stability The solder composition was filled in a polyethylene container, and placed in a thermostat bath at a temperature of 30 ° C for one month. After returning the solder composition after storage for one month to room temperature, the mixture was stirred for 1 minute using a spatula to observe the properties. Further, the storage stability was evaluated in accordance with the following criteria. A: The solder composition is in the form of a paste and is in a state of no change in properties. B: The solder composition was kept in a paste form, but the state in which the solder powder was agglomerated was confirmed. C: The solder composition was in a state of no smoothness without remaining in a paste form. [Table 1] As is clear from the results shown in Table 1, the results of the solder wettability, the flux residue cleanability, and the storage stability of the solder composition for precoat layers of the present invention (Examples 1 to 8) were good. It was confirmed that the solder wettability was excellent and sufficient storage stability was obtained.