200922407 九、發明說明： 【發明所屬之技術領域】 本發明關於一種利用在高溫下發泡之發泡板的柔性印刷電路板 (flexible printed circuit board 5 FPCB )。更具體而言，本發明關 於一種用於FPCB之發泡板，其藉由採用一相互反應性共聚物樹 脂作為一黏著層而具有優異的黏著強度且可藉由高溫加熱而輕易 地自被黏著體（adherend)分離，以及關於一種使用該發泡板以製 造FPCB之方法。 【先前技術】 近來，對於FPCB的需求已隨著電子產品（如行動電話、數位 相機、MP3播放器、DMB播放器或結合二或多種這些裝置之功能 的多功能產品）之小型化及輕量化而急速增加。 在傳統製造FPCB之方法中，由於FPCB之可撓性，在利用黏著 帶將FPCB固定在所謂載體或背板的基板上之後，才進行該方法。 近來，業經研究一種使用發泡板製造FPCB之方法，以利於在該 製造方法完成之後使FPCB自該黏著帶分離。 一般而言，在製造多層晶片電容器或晶片電感器時，發泡板主 要用作黏著或切割的支撐物。此時，喪失黏著力的條件為120至 130°C之溫度範圍及常壓下，且黏著力及發泡性為重要的物理性因 子。然而，在製造FPCB的情況中，發泡板在150至160°C及40 公斤/平方公分、歷時超過40分鐘的條件下（此為熱壓合（hot press lamination )之條件）應不會產生發泡室之破裂（break out of foam cell)，且應於熱壓合完成之後在較高溫度（即約180°C )下發泡。 200922407 並且，必須避免在製造FPCB之過程中因黏著性樹脂之轉移 (transcription)所造成的 FPCB 污染。 然而，由於傳統發泡板在約15(TC下開始發泡’無論發泡板的發 泡溫度多高，傳統發泡板在較高溫度下的橡用仍有限制。 同時，除了以如上所述使用在高溫下發泡的發泡板製造FPCB 之方法以外，業經提出一種藉由將FPCBs貼附至雙面發泡板之兩 面上來製造FPCB之方法，以提高FPCB製造商的獲利率。在這種 方法中，係使用雙面發泡板以於製造過程t固定FPCB。使用這種 方法，在不改變現有製程的情況下，經由單一製程同時生產兩個 產品，且因此在製造FPCB之方法中可將每單位時間的生產力加 倍。為了在製造多層FPCB或剛性FPCB之製程中提供靈活運用 度，不可避免地要製造單面FPCB。雖然有製造商裝備了能同時對 兩面進行加工的製造設備，但只有單一面β被加工，且因而在生 產力的提升上存在限制。然而，在目前製造FPCB之方法中’由 於可利用雙面黏著性發泡板來將FPCBs貼附至發泡板的兩面上而 同時加工兩面，則可將生產力加倍。並且，由於發泡板可取代形 成程序中之載體薄膜或氣墊薄膜的角色，則可能減少製造FPCB 之過程中所用之次要材料的消耗量。 用來藉由將單面FPCB貼附至發泡板之兩面上而進行製程的發 泡板’必須在160。(：之溫度及40公斤/平方公分之壓力且歷時超過 40分鐘的條件下不會發泡或受熱變形、對製造FPCB之過程期間 接觸發泡板之化學品具有抗化學性、於製造FPCB之製程完成後 在170至190°C下可輕易地發泡、以及避免在製造FPCB之過程期 200922407 間因黏著性樹脂之轉移所造成之FPCB的污染。 傳統上’使用主要含有交聯官能基及交聯劑的丙烯酸類黏著劑 作為發泡板產品之黏著劑。為了藉由使這種黏著劑凝聚在微球上 並限制微球的膨脹而提高發泡溫度，該黏著劑必須含有高比例的 交聯官能基，亦必須使用大量的交聯劑。因此，黏性會顯著改變， 且當父聯作用隨時間進行時，凝膠化作用隨之而進行，並且當塗 覆進行超過4小時，經塗覆之產品的物理性質在開始階段及結束 階段會變得不同。韓國專利申請案公開第1〇_2〇〇2_〇〇6〇659號、第 10-20〇2_0060656號與第i〇_2〇〇2_0〇6〇657號及韓國專利第 10-0514611號已提出使用發泡板以減少雙面連接式（加汕卜狀⑶“ type) FPCB、單面fpcb及薄FPCB之製程。然而，係透過以下 步驟進订FPCB之製造：去毛邊—貼附乾薄臈—曝光—顯影該乾 薄膜-腐仙-乾燥—捲繞—捲式切割—標籤黏合—形成覆蓋膜 (熱壓）-去毛邊—表面處理—無電電鑛—衝孔（卿ehing)。特 定言之’覆蓋臈（coverlay)形成程序係在15〇至16〇<)(：及4〇公斤 /平方公分且歷時超過4Q分鐘的條件下進行，且由於現有發泡板在 這種條件Τ的衫卿成㈣期时發泡，故訪㈣板只可用 在覆蓋膜形成程序之前的步驟。因此，傳統的發泡板並不實用。 有限公司（日本）之日本專利公開案第 2003-33關號揭示透過將單面Fp(：B貼附至發泡板之兩面上而使 用雙面發泡板料製㈣的髓薄膜。然而，這種Μ僅可部分 應用於使用目前可取得之發泡板之製造程序的起初階段中。 【發明内容] 200922407 〈技術問題〉 為解決以上問題，本發明之一目的係提供一種用於高溫發泡之 發泡板，其藉由採用一相互反應性共聚物樹脂作為一黏著層而具 有優異的黏著強度且可藉由在超過180°C下加熱而輕易地自被黏 著體分離，以及提供一種利用該發泡板製造FPCB之方法。 本發明之另一目的係提供一種製造FPCB之方法，其相較於傳 統製造單面FPCB之方法，可在單一製程中生產兩個單面FPCB， 因此增進FPCB製造方法的生產力，此係經由使用一雙面發泡板， 該雙面發泡板於熱壓程序期間，即使在160°C及40公斤/平方公分 且歷時超過40分鐘的高溫高壓條件下，仍維持黏著力，且該雙面 發泡板具有抗化學性而於蝕刻程序期間不會被蝕刻劑液體所滲 透。 <技術手段〉 本發明關於一種可用於高溫下之FPCB所用之發泡板，其藉由 採用一相互反應性共聚物樹脂作為一黏著層而具有優異的黏著強 度且可藉由在超過180°C下加熱而輕易地自被黏著體分離；本發明 亦關於一種使用該發泡板製造FPCB之方法。 此後將詳細描述一種製造可用於高溫下之FPCB所用之發泡板 的方法以及一種使用該發泡板製造FPCB之方法。對該製造FPCB 之方法而言，將接著描述一種製造單面FPCB之方法以及一種藉 由將FPCBs貼附至發泡板的兩面上來製造FPCB之方法。 本發明之用於高溫發泡的發泡板為一黏著板，其中使用混有含 熱膨脹性微球的相互反應性共聚物的黏著性樹脂來形成一黏著 8 200922407 層，且當§亥黏著層藉由加熱產生發泡或膨服時，其可在溫下分 離。 第1圖為一剖面圖，說明一用於製造單面發泡板之單面發泡板， 以及第2圖為一剖面圖，說明一用於製造FPCBs之雙面發泡板， 係藉由將FPCBs貼附至該發泡板之兩面上。 如第1圖所示，在依照本發明之單面發泡板中，依序堆疊一基 板1、一表面處理層2、一黏著層3及一離型膜（release film ) 4， 且該黏著層3含有熱膨脹性微球及相互反應性共聚物β 基板1可包含適合的商業化薄膜（如PET)並且具有較佳小於 250微米且最佳為25至1〇〇微米的厚度’但不限於此。在該基板 及該黏著層之間形成強化學鍵之表面處理層2係藉由在基板1上 進行化學性表面氧化處理所形成，例如鉻酸、臭氧、電暈（c〇r〇na)、 火焰、以及游離輻射處理，或在基板丨上處理具高極性之高分子 化合物如水解乙烯乙酸乙浠酯（hydr〇lyzed ethylene vinyi) 及聚乙烯丁醛。表面處理層2在加熱後分離時必須不會污染被黏 著體，且在製造FPCB之過程期間或在形成條件下不會被所使用 的化學品所改變。該表面處理層的厚度係小於5微米，且較佳係 小於1微米。較厚的表面處理層厚度在熱處理發泡板後導致較小 的黏著層變形及較少的黏著力降低。該表面處理層具有以下作 用.在使熱分離性黏著板黏附至該被黏著體時，維持良好的表面 屯狀並提供大_著面積，於此同時，在藉由加熱轉泡或賴 黏著板而將該黏著板自該被黏著體分離，減少該黏著板之表面方 向之發泡或膨脹上的限制並改進該黏著層之波狀變形。在直接將 200922407 «亥發/包黏^•層塗覆在該基板上而形成發泡板的情況巾，如果該黏 著層及該基板之p林存在㈣力’靠發泡層及該基板在發泡及 膨脹時會彼此分離。因此，達成所欲目的是不可能的。 黏著層3含有熱膨脹性微球以藉由加熱使該黏附至被黏著體的 黏著板輕易地自該被黏著體分離。藉由加熱該黏著層，熱膨脹性 微球發泡及膨脹而使黏著層產生穿孔。因此，接觸被黏著體之黏 著層的黏著面積會減少，因而可將該黏著板分離。 该熱膨脹性微球係一種材料，如異丁烷、丙烷及戊烷，其可輕 易氣化且具有熱膨脹性，且其外殼係由適合物質所構成，如偏二 乳乙烯及丙烯腈共聚物，該適合物f具熱祕性或可經熱膨服而 破碎。 具有10至25微米平均顆粒直徑的微球助於其藉由加熱而分散 至該黏著性樹脂中，且導致黏著層的大幅變形及黏著力的顯著降 低。再者，所形成之黏著層之厚度係大於微球之平均顆粒直徑， 較佳係大於最終微球之最大顆粒直徑。另外，較佳的是使該黏著 層之表面平滑且在加熱之前達到穩定的黏著力。為了藉由加熱以 降低該黏著層之黏著力’該熱膨脹性微球較佳細超過1G倍的體 積/脹比率而發泡及膨脹，並且具有使該熱膨脹性微球在該體積 膨脹比率下不會破碎的強度。 此外，由於在製造FpcB之製程中必然需要i6(rc之高溫，較佳 係使用具有盡可能高之開始發泡溫度的微球。 —熱膨脹性微球之含量是依照所欲的黏著層膨脹比率或所欲的黏 著力降低程度以適當地確定，但—般係小於5Q重量份，較佳係$ 200922407 至2〇重量份，以⑽重量狀構絲著層的轉性樹脂計。 為了使點著層可利用在接近1贼下開始發泡的熱膨脹性微球 :在FPCB製造程序中於m至贿的溫度範圍下被加熱必須 藉由限制微球之膨脹以提高發泡溫度。 構成該黏著層之相互反應性共聚物為一黏著性樹脂，其中該第 -共聚物係以乙烯基單體'乙稀基共聚單體及含縣之乙稀基單 體所共聚合而得，該第二共聚物係以乙稀基單體、乙婦基共聚單 體及含噁唑啉基之乙烯基單體所共聚合而得。 使用構成第一共聚物及第二共聚物的乙烯基單體及乙烯基共聚 單體是為了賦予黏著劑黏著力、内聚力'耐熱性、可撓性、滯留 性、彈性等等的目的（若有需要），且可獨立為選自以下之一者： 一或多個含燒基之乙稀基單體，選自丙稀酸甲醋、甲基丙浠酸甲 酯、丙烯酸乙酯、甲基丙烯酸乙酯、丙烯酸丙酯、子基丙烯酸丙 酯、丙烯酸丁酯、甲基丙烯酸丁酯、丙烯酸己酯、甲基丙烯酸己 酯、丙烯酸辛酯及丙烯酸2-乙基己基酯；一或多個含羥基之乙稀 基單體’選自丙婦酸經乙基醋、甲基丙稀酸經乙基醋、丙婦酸經 丙基酯、曱基丙烯酸羥丙基酯、丙烯酸羥丁基酯、f基丙稀酸經 丁基酯 '丙烯酸羥己基酯及甲基丙烯酸羥己基酯；一或多個含N_ 取代醯胺乙烯基單體，選自N，N-二甲基丙烯醯胺及n，N-二甲基甲 基丙稀醯胺；一或多個炫氧基烧基丙烯酸酯乙烯基單體，選自丙 烯酸甲氧基乙基醋、曱基丙烯酸甲氧基乙基醋、丙稀酸乙氧基乙 基酯及甲基丙烯酸乙氧基乙基酯；一或多個乙烯基單體，選自乙 酸乙烯酯、丙酸乙烯酯、N-乙烯基。比洛烧酮、甲基乙烯基吼嘻烧 200922407 酮、乙晞基吡啶、乙烯基哌啶酮、乙烯基嘧啶、乙烯基派„秦 (vinylpiperazine )、乙烯基0比嗪（vinylpyrazine )、乙稀基 °比〇各、 乙烯基咪唑、乙稀基噁嗤、乙稀基嗎琳、N-乙稀基甲醯胺、苯乙 烯、α-甲基苯乙烯及N-乙稀基己内醯胺；一或多個氰基丙稀酸酉旨 單體，選自丙烯腈及甲基丙烯腈；一或多個含環氧基之丙稀酸單 體，選自丙稀酸縮水甘油酯及甲基丙稀酸縮水甘油酯；—或多個 乙二醇丙稀酸酯單體，選自聚乙二醇丙烯酸酯、聚乙二醇甲基丙 烯酸酯、聚丙二醇丙稀酸醋、聚丙二醇甲基丙浠酸酯、甲氧基乙 二醇丙烯酸酯、曱氧基聚乙二醇甲基丙烯酸酯、甲氧基聚丙二醇 丙烯酸酯及曱氧基聚丙二醇甲基丙烯酸酯；一或多個丙稀酸醋單 體，選自丙烯酸四氫糠基酯 '甲基丙烯酸四氫糠基酯及丙稀酸 曱氧基乙基酯；一或多個單體，選自異戊二烯、丁二烯、異丁烯 及乙稀基鰱；或前述之二或多者之混合物。 利用該第一共聚物之含羧基之乙烯基單體是為了藉由自由基聚 合反應而賦予交聯性質的目的，且其實例包含2、3或多種選自一 官能性單體的共聚物’該官能性單體為例如一或多個選自丙稀 酸、曱基丙烯酸、丙烯酸羧乙基酯、丙烯酸羧戊基酯、衣康酸、 順丁烯二酸、反丁烯二酸及巴豆酸之含羧基之單體；以及一或多 個選自順丁烯二酸酐或衣康酸酐之酸酐單體。 該第一共聚物較佳係由乙烯基單體、乙烤基共聚單體及含竣基 之乙烯基單體以i : 〇.5至L5 : 〇.〇5至〇.3之重量比所製造。利用 該第二共聚物之含噁唑啉基之乙烯基單體是為了藉由自由基聚合 反應而賦予交聯性質的目的，含噁唑啉基之乙烯基單體的實例包 12 200922407 含2-乙烯基·2-噁唑啉、2-乙烯基-4-乙烯基-2-噁唑啉、2-乙烯基-5-乙稀基-2-°惡嗤琳、2-異丙浠基-2-°惡°坐琳、2-異丙浠基-5-乙基-2-噁唑啉、2-異丙烯基-5-曱基-2-噁唑啉、2-(乙烯苄氧基-1-甲基乙 基）-2-噁唑啉、2-(2-羥基-1-曱基乙基）丙烯酸酯 '及2-(2-羥基-ΐ_ 甲基乙基）甲基丙稀酸醋、或前述之二或多者之混合物。 該第二共聚物較佳係由乙烯基單體、乙烯基共聚單體及含噁唑 啉基之乙烯基單體以1 : 0.5至1.5 : 0,05至0.3之重量比所製造。 供本發明FPCB之發泡板之黏著層用的塗覆液係藉由在分別製 備含羧基之第一共聚物及含噁唑啉基之第二共聚物後，將微球分 散至由第一共聚物及第二共聚物混合所得的黏著性樹脂中所製 備。所製得之用於黏著層的塗覆液係穩定的，儘管在室溫下長期 貯存仍不會產生顯著的改變，並且相較於傳統發泡板的塗覆液可 提高發泡溫度最高達1 〇至3〇t：。 該黏著層必須在16 01之溫度及4 0公斤/平方公分之壓力下歷時 40分鐘内不會發泡或受熱變形、對製造FpCB之製程期間接觸該 黏著層之化學品具有抗化學性、以及不會在製造FpCB之製程期 間因黏著性樹脂之轉移而污染FPCB。再者，黏著層必須在17〇至 190 C之溫度下於一對流烘箱中5至1〇分鐘内或於一加熱板中ι〇 秒至3分鐘内輕易發泡，此乃在完成製造FpCB之製程後輕易地 自被黏著體分離的加熱條件。 同時，如第2圖所示，在依照本發明之雙面發泡板中，依序堆 疊一離型膜4，、一黏著層3，、一表面處理層2，、一基板丨、一表面 處理層2、-黏著層3及-離型膜4,黏著層3及3,包含熱膨服性 13 200922407 微球及相互反應性共聚物。各元件之細節與用於FPCB之單面發 泡板相同。 下文將描述一種使用本發明之發泡板製造FPCB之方法。 使用單面發泡板製造單面FPCB係透過以下步驟進行：層壓 FCCL及發泡板一去毛邊一層壓乾薄膜一曝光一顯影一触刻一分 離該乾薄膜一標籤黏合一熱壓一表面處理一衝孔一分離該發泡 板。 同時，亦進行一種藉由將FPCBs貼附至雙面發泡板來製造FPCB 之方法，如上所述，係透過以下步驟：層壓FCCL及發泡板一去 毛邊一層壓乾薄膜—曝光一顯影__钮刻一分離該乾薄膜—標箴黏 合一熱壓一表面處理一衝孔一分離該發泡板。然而，在層壓FCCL 及發泡板之步驟中，使用雙面發泡板以將FCCL層壓至發泡板的 兩面上，如此可同時對經黏附之FCCL的兩面進行製程，且接著 進行其餘步驟。因此，經由分離該發泡板，以單一製程可同時製 造兩個單面FPCB。 <有利功效> 本發明可提供一種使用一發泡板製造FPCB之方法，該發泡板 在熱壓程序期間即使在高溫高壓的條件下還維持黏著力、具有抗 化學性而於蝕刻程序期間不會被蝕刻劑液體所穿滲、且可藉由高 溫加熱輕易地自被黏著體分離。 【實施方式】 由以下較佳之具體實施態樣之描述及所附圖式，可使本發明上 述之目的、特徵及優點變得更清楚。 14 200922407 <最佳方式> 下文將參照附圖詳細描述本發明之用於fpcb之發泡板，其使 用一相互反應性共聚物樹脂作為—黏著層而具有優異的黏著強度 並且可藉由超過鮮c之加熱處理輕易地自被黏著體分離，以及使 用該發泡板製造FPCB之方法。然而，該具體實施態樣僅為說明 之目的’本發明之範圍不限於此。 [製造實例1] 第一共聚物之製造 在裝有授拌器、冷凝器、滴液漏斗、溫度計及爽套的2升玻璃 反應器巾’將.45克作為單體之丙婦酸乙g旨、45克作為共聚單體之 丙烯酸正丁 S旨及1G克丙婦酸混合，且進_步—同添加請克α，α，_ 偶氮二異丁腈（作為引發劑）與1〇〇克乙酸乙醋及2〇克甲苯，接 著於下進行自由基聚合反應。經過3()分鐘之後，添加並混合 克丙稀S文乙5曰、135克作為共聚單體之丙烯酸正丁酯及克 丙烯酉文。將0.5克作為引發劑之α，α’_偶氮二異丁腈溶解於⑽克 酉曰及40克甲本中，接著使用滴液漏斗滴加所得溶液歷時約 90分鐘。於滴加期間維持溫度恆定。為了在反應完成之後消除殘 餘的早體’將1克自由基引發劑溶解於5〇克乙酸乙醋及5〇克乙 醇中並接著滴加歷時60分鐘，接著進-步反應3小時，由此製得 第一共聚物。 第二共聚物之製造 在裝有攪拌器、冷凝器、滴液漏斗、温度計及夾套的2升玻璃 ’V«器中，將45克作為單體之丙浠酸乙酯、45克作為共聚單體之 15 200922407 =丁醋及…異丙稀基_2侧混合。將。〇ι克作為 之y，-偶氮二異丁腈溶解於⑽克乙酸乙㈣如克甲苯 中並且接著添加至反應器中， 相同方切抑下進行❹十 聚合含m基之共聚物的 _ …進行自由基聚合反應。經過30分鐘 丫添加並犯σ 135克丙締酸乙醋、出克作為共聚單體之丙稀 夂正丁 _及30克丙稀酸。將〇·5克作為引發劑之a〆·偶氮二異丁 輕解於刚克乙酸乙岐4〇克甲苯中，接著使用滴液漏斗滴加 所付浴液歷時約90分鐘。於滴加期間維持溫度蚊。為了在反岸 完成之後消除殘餘的單體，们克自由基引發劑溶解於％克乙酸 乙醋及50克乙醇中並接著滴加歷時⑼分鐘，之後進—步反應3 小時’由此製得第二共聚物。 黏著性樹脂之製造 以1: 1之«比混合上述所製造之第—共聚物及第二共聚物。 將H)克微球（產品名稱：F8GVSD，可自松本油脂製藥株式會社 購得’在⑼^贼下開始發幻添加並分骸⑽^的混合樹 脂中，由此製得一黏著性樹脂。 [製造實例2] 藉由如製造實例1中所描述的相同方式製造黏著性樹脂，但製 造第-共聚物及第二共聚物所使用之單體的重量比各自為丙烯酸 乙雖/丙稀酸正丁醋/丙稀酸=4.5/4.5/1.5及丙烯酸乙酯/丙稀酸正丁 酯/2-異丙稀基-2-°惡唆琳=4.5/4.5/1.5。 [製造實例3] 藉由如製造實例1中所描述的相同方式製造黏著性樹脂，但製 16 200922407 造第一共聚物及第二共聚物所使用之單體的重量比各自為丙烯酸 乙酯/丙烯酸正丁酯/丙烯酸=4,5/4.5/0.6及丙烯酸乙酯/丙稀酸正丁 酯/2-異丙稀基-2-°惡嗤琳=4.5/4.5/0.6。 [製造實例4] 藉由如製造實例1中所描述的相同方式製造黏著性樹脂，但製 造製造實例1之第二共聚物所使用的單體為丙烯酸2_乙基己基酯/ 甲基丙烯酸甲酯/丙烯酸正丁酯/2-異丙烯基_2_噁唑琳 =2.0/2.5/4.5/1.0 。 [製造實例5] 藉由如製造實例4中所描述的相同方式製造黏著性樹脂，但製 造製造實例4之第二共聚物所使用之單體的重量比為丙烯酸2_乙 基己基酯/甲基丙烯酸甲酯/丙烯酸正丁酯/2_異丙烯基_2_噁唑啉 =2.0/2.5/4.5/1.5 。 [實例1至5] 經由將製造實例1至5所製造的黏著性樹脂塗敷於聚對苯二甲 酸乙二醋薄膜（PET薄膜）（5〇微米）上、於其上形成37微米發 泡黏著層、以及貼附36微米離型膜於其上而製造一發泡板，並且 接著將該發泡板老化歷時7天。藉由將FpCbs貼附至該發泡板之 兩面上來製造單面FPCBs之全部程序係透過以下步驟進行：層壓 FCCL及發泡板—去毛邊一層壓乾薄膜—曝光—顯影—蝕刻一分 離該乾薄膜一標籤黏合—熱壓一表面處理—衝孔—分離該發泡 板。接著，對各個步驟評估效能。 A.FCCL之選擇 17 200922407 一般而言，以銅箔、黏著劑、聚醯亞胺薄膜之厚度及該銅箔之 種類來分類用於單面FPCB的FCCL。在目前的具體實施態樣中， 使用具有表1中所示之規格的銅箔。製造產品中所用覆蓋膜在黏 著層的厚度為25微米且在聚醯亞胺層的厚度為25微米。 [表1] 樣品 製造商 PI之厚度 黏著劑之 厚度 銅之厚度 銅之種類 總厚度 樣品1 Hanwha L&C 25微米 15微米 l/2oz 電解銅 (ED) 57.5微米 B. 層壓（FCCL及發泡板） 表這彳έ步驟中，層Μ發泡板及FCCL以使FCCL黏附至發泡板 上。層壓是使用一般的層壓機，以單面FCCL之銅箔面朝外且將 聚醯亞胺之表面黏附至發泡板的方式來進行。避免在經黏附之產 品中產生聚醯亞胺之氣泡及皺褶，且確定周圍部分的黏附狀態， 如此於後續步驟中各種化學品不會因為在周圍處的黏著力降低而 滲入該經黏附之產品。 C. 去毛邊 在去毛邊步驟中，去除塗在銅箔表面上用來防止銅箔表面腐蝕 的防鏽劑，銅箔表面上會產生不平坦（unevenness )而增加銅箔的 表面積並提高對乾薄膜（感光樹脂）的黏著力。此步驟是經由化 學方法之輕微腐#銅的表面而進行，且使用硫酸（H2S〇4 )及過氧 化氫（H2〇2)的混合溶液作為化學品。 D. 層壓乾薄膜 乾薄膜層壓係一種將感光樹脂黏附於銅箔上而在銅箔上形成電 18 200922407 路的步驟。當製造單面FPCB時，於銅箔表面上層壓乾薄膜，且 由於FCCL很薄，將位在相反面的聚醯亞胺表面貼附至一載體薄 膜上，以防止在後續步驟中產生皺摺或撕裂。 E. 曝光 在曝光步驟中，當為形成電路而將紫外線（UV)照射在一放置 於黏附有感光樹脂之FCCL上方的光罩薄膜時，該UV不能透射該 光罩薄膜之黑暗部分且僅能透射該光罩薄膜之透明部分。因此， 交聯作用僅發生於該乾薄膜有接受到UV的部分。 F. 顯影 使該乾.薄膜暴露於3%碳酸鈉.溶液中。結果，.接受UV而產生交 聯作用的部分未被溶解，但未接受UV而未發生交聯作用的部分 則被溶解而曝露出銅。 G. 蝕刻 乾薄膜在將藉由顯影形成電路的部分處覆蓋銅箔而作為抗蝕 劑，且將蝕刻劑（CuCl2、HC1、H2〇2 )加到經曝露的銅箔上以腐 蝕除電路以外之其餘部分的銅箔。 個別步驟中所用的化學品及加工條件係列於表2中。 [表2] 程序 詳細程序 化學品 溫度 時間 方式 作用 形成 電路 去毛邊 h2so4、h2o2 溶液 25 至 28°C 約20秒 噴塗 將銅绪表面去毛邊 顯影乾薄 膜 Na2C03溶液 30 至 35°C 約30秒 噴塗 溶解光固化樹脂 姓刻 CuCl2、HC 卜 H2〇2 38 至 42°C 約60秒 喷塗 腐ϋ銅表面 19 200922407 Η·標籤黏合 在藉由蝕刻以在FCCL中形成電路之後，為保護電路，將覆蓋 膜黏附到除了將與連接器連接的部分及將經焊接而供安裝零件 (mounting parts )用之部分以外的電路部份。由於覆蓋膜係經熱 固性黏著劑塗覆，所以黏著力很微弱。因此，在藉由熱壓進行黏 著劑之固化以前，該覆蓋膜及已形成電路的FCCL係使用焊接而 部分地且暫時地被固定，以防止該覆蓋膜移動。 I.熱壓 熱壓是為了藉由熱固作用而黏附覆蓋膜，且在表3所顯示的條 件下進行。於此步驟中，使用加熱及加壓條.件下歷經一預定時間 的熱壓以使覆蓋膜之黏著劑受熱固化。為了使用該發泡板，於此 步驟之加工條件下，該發泡板必須未發泡，且該發泡板及FPCB 必須沒有外部形狀的變形或尺寸的改變。 [表3] 設備 模式 類型 加工條件 壓力 溫度 時間 Younshin H/P 發泡板測試 雙面 51公斤/ 平方公分 160。。 105分鐘 J.表面處理 一般使用無電電鍍法進行表面處理，且該無電電鍍法為批式並 在表4所示的條件下進行。金鍍覆為一複雜的程序且在金鍍覆之 前進行使用下表所列之化學品的預步驟。 [表4] 程序 詳細程序 化學品 溫度 時間 方式 作用 金鍍覆 清潔 表面活性劑 36 至 40°C 約3分鐘 沉積 去除氧化層並清潔 20 200922407 活化 PdCl2、HC1 溶液 25 至 28°C 約3分鐘 沉積 以把（Pd)取代 PCB的銅箔 鎳鍍覆 NiCl2、 h2po2、錯合 劑 80 至 90°C 約10分鐘 沉積 無電鎳鍍覆 酸沉積 H2S〇4 25 至 28°C 約4分鐘 沉積 酸處理 金鍍覆 K[Au(CN)4] 80 至 90°C 約8分鐘 沉積 無電金鍍覆 κ.形成外部形狀（衝孔） 為完成最終產品，將以經貼附之發泡板加工的fpcb進行衝孔 以形成外部形狀。在此時，依模具之位置精確安裝導向孔以形成. 外部形狀。 L.分離發泡板 - · · · · - . 於此步驟中，必須將該發泡板之兩面上所貼附的FPCBs分離。 該發泡板之特性在於，藉由發泡室在預定溫度下之膨脹造成黏著 力降低而被分離。發泡溫度已經過設計使得該發泡板在至少17 0 °C下發泡。完成表面處理的產品係利用如對流烘箱之加熱裝置來 進行分離。 [比較製造實例1] 在裝有攪拌器、冷凝器、滴液漏斗、溫度計及夾套的2升玻璃 反應器中，將48.5克丙烯酸正丁酯、48.5克丙烯酸乙酯、2克丙 烯酸、1克丙烯酸羥丙基酯及〇.〇1克α，α’-偶氮二異丁腈溶解於160 克乙酸乙酯及270克曱苯中，之後加入滴液漏斗中，接著以氮替 換後之連續流，在80°C下滴加時進行自由基聚合反應歷時8小 時。在反應終了時，加入過量之自由基引發劑以消除殘餘的單體， 且接著加入10克微球（產品名稱：F80VSD，可自松本油脂製藥 株式會社購得，在150至160°C下開始發泡）並分散，之後以黏著 21 200922407 性樹脂中羥基官能基含量的兩倍量添加里s祕& 異虱酸酯交聯劑（產品名 稱：AK-75,愛敬化學有限公司）並攪拌，士 &制 件由此製得該黏著性樹脂。 [比較製造實例2] 藉由如比較製造實例1中所描述的相因古 目冋方式製造黏著性樹脂 但具有交聯官能基之丙稀酸經丙基酯的用量增加至2〇克。 [比較製造實例3] 藉由如比較製造實例1中所描述的相 疋的相问方式製造黏著性樹脂， 但以黏著性樹脂中羥基官能基含量的 借里添加異氰酸酯交聯劑 (產品名稱：AK-75，愛敬化學有限公司）。 [比較製造實例4] 精由如比較製造實例2中所描述的相同方式製造黏著性樹脂， 但以黏著性樹脂中羥基官能基含量的四倍量添加異氰酸酯交聯劑 (產品名稱：AK-75,愛敬化學有限公司）。 [比較實例1至4] '’工由將比製造實例1至4所製造的黏著性樹脂塗敷於叩T薄 膜（50微米）上、於其上形成37微米發泡黏著層 '以及貼附％ 微米離型膜於其上而製造-發泡板。將所製造的發泡板老化歷時7 天並接著用於最終測試卜藉由將FpCBs^附至該發泡板的兩面 上來製ie_單面FPCB之整個程序係透過以下步驟進行：層壓FCCL 及發/包板去毛邊一層壓乾薄膜一曝光一顯影—蝕刻—分離該乾 4膜-域黏合—熱壓—表面處理—衝孔—分離該發泡板。接 著，對各個步驟評估效能。 為了對使用上述製造實例、比較製造實例、實例及比較實例所 22 200922407 製造的黏著性樹脂及發泡板而藉由將FPCBs貼附至發泡板的兩面 上來製造單面FPCB之方法進行測試，在以下材料及加工條件下 對每一個製造FPCB之步驟評估用於咼溫發泡之發泡板的可靠性。 1. 未加工板之選擇 為用於FPCB之製造’用於發泡板之未加工板經過設計使得發 泡劑在至少180°C下發泡成最適體積。因此，由於必須在發泡時使 熱傳遞達到最大且必須在考慮可加工性或捲式方法的情況下具有 可撓性，使用厚度為25至1〇〇微米之PET薄膜。另外，由於重複 進行加熱至.而溫及冷卻至室溫’必須沒有尺寸上的熱改變。為了 符合這種條件’使用厚度為50微米之基板及厚度為36微米之離 型膜。 2. 發泡之條件及方法 一般而言，使用對流烘箱及加熱板以分離發泡板。使用最小寬 度超過250毫米之發泡板於FPCB之製造中，且由於在熱壓步驟 中該發泡板必須是可耐用的，所以發泡劑本身應具有高發泡溫度 之物理性質。因此，依照所欲的發泡力及FPCB的尺寸改變而在 考慮熱傳導效率的情況下選擇發泡板分離設備。 3. 可靠性之評估 將該發泡板應用到製造單面FPCB之方法中，且接著確認是否 可能藉由將FPCBs貼附至發泡板的兩面上來製造FPCB而將製程 效率加倍，及減少由於薄厚度的FPCB所導致之在製造程序中產 生的皺摺或撕裂。尤其，當使用該發泡板加工時，另外實驗是否 該發泡板本身會提高FPCB之品質，及是否製造FPCB之程序中會 23 200922407 產生負面因子而降低生產力並生產出不良產品。 使溫度維持在70°C，將FCCL層壓至發泡板的兩面上。在層壓 步驟期間，在經黏著之產品中不會產生聚醯亞胺之氣泡及皺褶。 尤其，確定周圍部分的黏著狀態，如此各種化學品不會因為周圍 處的黏著力降低而滲入經黏著之產品，且結果顯示出強的黏著 力。即使當黏附有銅箔之發泡板被捲繞在捲筒中而彎曲時，也沒 有發現發泡板與銅箔之分離。去毛邊所用之化學品為硫酸（h2so4) 及過氧化氫（h2o2)的混合溶液，且可確認該溶液不會滲入黏附 於該發泡板的表面。於此步驟中，當將FCCLs貼附至該發泡板的 兩面上時仍可維持厚度，因而不需要載體薄膜，該載體薄膜為一 種次要材料。再者，可確認由於乾薄膜同時層壓至兩面上，工作 程序降低至50%。另外，亦可確認曝光機自正面及背面照射UV 以在曝光步驟中同時曝光兩面，且由於在利用發泡板進行曝光步 驟時可對兩面同時曝光，故生產力增進至兩倍。藉由將FCCLs貼 附至發泡板的兩面上而進行之FCCLs分離程序，已確認不會影響 產品品質，且亦確認可提昇加工之簡易度。在顯影步驟中，沒有 發現因顯影液（Na2C03)之滲透所造成的分離現象。在蝕刻步驟 中，類似於顯影步驟，有由於強酸溶液之滲透而造成FCCL及該 發泡板分離的可能性，但在實際測試中沒有發現該分離現象。在 標籤黏合步驟中，使用熨斗（iron)且當使用該發泡板進行加工時 也使用熨斗。因此，必須使發泡板不會因為熨斗而發泡，且可證 實在標籤黏合步驟之後沒有發生部分發泡。 為了在熱壓步驟期間證實尺寸穩定性，使用及未使用該發泡板 24 200922407 製造之產品的尺寸係利用三維測量器來測量。尺寸穩定性之目標 值設定為小於0.03%。 因化學品之滲透而造成該發泡板的分離是無電電鍍（即表面處 理步驟）中的重要問題。在本發明中的無電電鍍步驟中，使用一 種沉積方式的化學處理且由目視檢測（visual testing )之結果可證 實液體不會滲透。 於此步驟中，應分離貼附至該發泡板兩面上的FPCBs。該發泡 板藉由發泡室在預定溫度下之膨脹造成黏著力降低而分離。發泡 室經過設計以在至少170°C下發泡。完成表面處理的產品係使用如 對流烘箱之加.熱裝置而分離。完全分離之FPCB所需的證明因子 如下文所述。第一，該發泡板之黏著劑應該未轉移至FPCB之背 面上。第二，在發泡及分離步驟中應該未產生產品上的皺摺。第 三，在使用該等化學品的整個程序中，該發泡板應該避免液體之 滲透所造成的沾污。實際上，產品上的皺褶係於自該發泡板中不 均勻顆粒大小之發泡室之發泡之後而產生的。然而，可藉由使該 發泡板之顆粒大小及粒徑分佈皆為均勻，生產具有與現有利用單 面發泡板之方法相同品質的最終產品。表5顯示將實例及比較實 例所獲得之樣本應用至製造FPCB之方法中的結果。 [表5] \樣本 步驟 \ 實例1 實例2 實例3 實例4 實例5 比較實例1 比較實例2 比較實例3 比較實例4 層壓 良好 良好 良好 良好 良好 良好 良好 良好 良好 去毛邊 良好 良好 良好 良好 良好 良好 良好 良好 良好 層壓乾薄膜 良好 良好 良好 良好 良好 良好 良好 良好 良好 曝光 良好 良好 良好 良好 良好 良好 良好 良好 良好 顯影 良好 良好 良好 良好 良好 良好 良好 良好 良好 蝕刻 良好 良好 良好 良好 良好 良好 良好 良好 良好 25 200922407 分離乾薄膜 良好 良好 良好 良好 良好 良好 良好 良好 標殲黏合 良好 良好 良好 良？^ ----^ 良好 良好 良好 良好 良好 熱* 良好 良好 良好 良 ---一^ 不佳 不佳 不佳 不佳 (未發泡） (未發泡） (未發泡> (未發砲） ί未發泡> (發泡分離） (發泡分離） (發泡分離） (發泡分離） 表面處理 良好 良好 良好 良 良好 - - - - 衝孔 良好 良好 良好 良 -_ 良好 - - - - 分離發泡板 良好 (發泡分離） 良好 (發泡分離） 良好 (發泡分離） 良 (發泡分離） ---- 良好 (發泡分離） - - - - 為了確認熱壓步驟之後的尺寸穩定性，使用三維測量器來測量 使用該發泡板所製造之產品的尺寸以及藉由現有方法使用單面發 泡板所製造之產品的尺寸。如第4調及第5圖所示，所測得之結 果顯示尺寸改變之速率係小於〇.Q3。/。，此乃尺寸穩定性之目標值。 這表示在使用該發泡板加工時尺寸問題不會影響產品的製造。 當進行藉由將FPCBs貼附至發泡板之兩面上來製造FPCBs之方 法時，製造過程中會添加各種化學界。確認是否該發泡板之黏著 劑會溶解於所使用的化學品中且被戶斤使用的化學品滲透。如果該 黏著劑被溶解且被滲透，則不可能進行因該黏著劑之黏著力降低 而造成該發泡板與FCCL分離的程序，且可能產生因液體之滲透 所造成之FCCL之污染。然而，本發明之發泡板不會產生因化學 品（如蝕刻劑液體等等）之滲通所造成的品質問題。並且，自表6 可確認藉由將FPCBs貼附至該發泡板之兩面上之單面FPCBs之方 法在生產力上所達之提昇效果。 [表6] 程序 描述 效果 層壓發泡板 -層壓FCCL及發泡板以藉由將FCCLs貼附至發 泡板之兩面上來加工FCCL 工作程序增加100% 層壓乾薄膜 -同時層壓兩面 -在使用單面發泡板加工時將載體薄膜貼附至背 面 工作程序降低至50°/〇 不需要載體薄膜 26 200922407 1 -在使用發泡板時不需要載體薄膜 1 ~~~~~- 曝光 -可在使用發泡板時同時曝光兩面 — 顯影 -可在使用發泡板時同時顯影兩面 工<rw/ 钱銅 -可在使用發泡板時在兩面上同時腐钱銅 1工作盘降併f叩〇/ P離乾溥膜-可在使用發泡板時在兩面上同時分離乾薄膜- 1~乾燦 1 -可在使用發泡板時同時乾燥兩面 1工π。/ 去除載體薄 m 在使用發泡板時是不需要的 工作程序降低〗〇〇% •在去除載艎薄膜時可減少皺摺和撕裂 ^籤黏合 -此步驟在藉由將FCCLs貼附至發泡板之兩面上工作程序降低〇%… 來加工FCCL時與在使用單面發泡板加工時相同 Γμμ •在藉由將FCCLs貼附至發泡板之兩面上來加工安裝量增加3〇% 裝量增加 次要材糊f降低50% -用於藉由將FCCLs貼附至發泡板（PVC薄臈、 PET薄膜及氣墊薄膜）之兩面上來加工FCCL的 次要材料用量降低至50%__ ^^處理之前同時進行去毛邊 隆低至50%— J在使用發/包板時同時表面處理兩面 工作程庠降低i_ 50% 分離發泡板 刀離藉由將rccLs貼附至發泡板之兩面上來加|卫作程序增加1〇〇0/。 工FCCL所製得的產品 .. 〜战導向孔 -形成導向孔之程序係與使用單面發泡板加工^|·相同 相同 〜成外部形 成外淖形狀之私序係與使用單面發泡板加工相同 時相同 终產品之程序係與制單面發泡板加了1—㈣ <產業可利用性> 如上所述，依照本發明可提供一種使用一發泡板製造fpcb之 方去a u板在熱壓程序期間在高溫高壓的條件下還維持黏著 力、具有抗化學性而於㈣程序期間*會被㈣劑液體滲透、並 且藉由高溫加熱可與被黏著體分離。 再者，於本發明中，相較於傳統製造單面FPCB之方法’由於 利用*面發泡板，因此可在單一製程中生產兩個單面FpcB並 且因而增進FPCB製造方法的生產力。 【圖式簡單說明】 27 200922407 第1圖係一剖面圖，說明本發明之單面發泡板； 第2圖係一剖面圖，說明本發明之雙面發泡板 第3圖係一圖表，顯示本發明所用之熱壓之加工條件； 第4圖係一圖表，顯示在使用本發明之發泡板加工時尺寸改變 之速率；以及 第5圖係一圖表，顯示在使用傳統單面發泡板加工時尺寸改變 之速率。 【主要元件符號說明】 1 基板 2 表面處理層 2’ 表面處理層 3 利用相互反應性共聚物之混合物的發泡板 3 ’ 利用相互反應性共聚物之混合物的發泡板 4 離型膜 4’ 離型膜 28200922407 IX. Description of the Invention: [Technical Field] The present invention relates to a flexible printed circuit board (FPCB) using a foamed sheet which is foamed at a high temperature. More specifically, the present invention relates to a foamed sheet for an FPCB which has excellent adhesion strength by using a mutually reactive copolymer resin as an adhesive layer and can be easily adhered by heating at a high temperature. Adherend separation, and a method of using the foamed sheet to manufacture an FPCB. [Prior Art] Recently, the demand for FPCB has been miniaturized and lightened with electronic products such as mobile phones, digital cameras, MP3 players, DMB players, or multifunctional products that combine the functions of two or more of these devices. And it has increased rapidly. In the conventional method of manufacturing an FPCB, the method is performed after the FPCB is fixed on a substrate of a so-called carrier or a backing plate by an adhesive tape due to the flexibility of the FPCB. Recently, a method of manufacturing an FPCB using a foamed sheet has been studied to facilitate separation of the FPCB from the adhesive tape after the manufacturing method is completed. In general, when manufacturing multilayer wafer capacitors or wafer inductors, the foamed sheet is primarily used as a support for adhesion or cutting. At this time, the conditions for loss of adhesion are in the temperature range of 120 to 130 ° C and under normal pressure, and adhesion and foaming are important physical factors. However, in the case of manufacturing FPCB, the foamed sheet should not be produced under conditions of 150 to 160 ° C and 40 kg / cm 2 for more than 40 minutes, which is the condition of hot press lamination. The foaming chamber breaks out of the foam cell and should be foamed at a higher temperature (i.e., about 180 ° C) after the thermocompression is completed. 200922407 Also, FPCB contamination due to the transfer of adhesive resin during the manufacture of FPCB must be avoided. However, since the conventional foamed sheet starts to foam at about 15 (TC) regardless of the foaming temperature of the foamed sheet, the rubber of the conventional foamed sheet at a higher temperature is still limited. In addition to the method of manufacturing an FPCB using a foamed sheet which is foamed at a high temperature, a method of manufacturing an FPCB by attaching FPCBs to both sides of a double-sided foamed sheet has been proposed to increase the profitability of the FPCB manufacturer. In this method, a double-sided foamed sheet is used to fix the FPCB during the manufacturing process. With this method, two products are simultaneously produced via a single process without changing the existing process, and thus the FPCB is manufactured. The method can double the productivity per unit time. In order to provide flexibility in the manufacturing process of multi-layer FPCB or rigid FPCB, it is inevitable to manufacture single-sided FPCB. Although some manufacturers are equipped with manufacturing that can process both sides at the same time. Equipment, but only a single face β is processed, and thus there is a limit in productivity improvement. However, in the current method of manufacturing FPCB, 'because of the double-sided adhesive foam board can be utilized Attaching FPCBs to both sides of the foamed sheet while processing both sides doubles the productivity. Also, since the foamed sheet can replace the role of the carrier film or air-cushion film in the process, it is possible to reduce the process of manufacturing the FPCB. The consumption of the secondary material used. The foamed sheet used for the process by attaching the single-sided FPCB to both sides of the foamed sheet must be at 160. (: temperature and pressure of 40 kg/cm 2 And it will not foam or be deformed by heat for more than 40 minutes. It is chemically resistant to the chemicals that contact the foam board during the process of manufacturing FPCB. It can be easily used at 170 to 190 °C after the process of manufacturing FPCB is completed. Foaming and FPCB contamination caused by the transfer of adhesive resin during the manufacturing process of FPCB 200922407. Traditionally, 'acrylic adhesives mainly containing cross-linking functional groups and cross-linking agents are used as foaming boards. Adhesive of the product. In order to increase the foaming temperature by agglomerating the adhesive on the microspheres and limiting the expansion of the microspheres, the adhesive must contain a high proportion of cross-linking functional groups, and must A large amount of cross-linking agent must be used. Therefore, the viscosity will change significantly, and when the parental action is carried out over time, the gelation proceeds, and when the coating is carried out for more than 4 hours, the coated product The physical properties will be different at the beginning and end stages. Korean Patent Application Publication No. 1〇_2〇〇2_〇〇6〇659, No. 10-20〇2_0060656 and No.i〇_2〇〇2_0 〇6〇657 and Korean Patent No. 10-0514611 have proposed the use of a foamed sheet to reduce the process of double-sided connection (additional (3) "type" FPCB, single-sided fpcb and thin FPCB. However, Step-by-step manufacturing of FPCB: deburring - attaching dry enamel - exposure - developing the dry film - rot - drying - winding - roll cutting - label bonding - forming a cover film (hot pressing) - deburring - surface Treatment - no electricity mine - punching (qing ehing). The specific coverage of the coverlay formation process is between 15 and 16 <) (: and 4 〇 kg / cm ^ 2 and lasted more than 4Q minutes, and because the existing foam board is foamed in the condition of the 卿 成 成 (4) period, the visit (four) board can only be used in The film is formed before the film forming process. Therefore, the conventional foaming plate is not practical. The Japanese Patent Publication No. 2003-33 of the Japanese Patent Publication No. 2003-33 discloses the attachment of a single-sided Fp (:B to a foamed plate). The medullary film of the (4) double-sided foamed sheet material is used on both sides. However, such enamel can only be partially applied to the initial stage of the manufacturing process using the currently available foamed sheet. [Summary of the Invention] 200922407 Problem In order to solve the above problems, it is an object of the present invention to provide a foamed sheet for high-temperature foaming which has excellent adhesion strength by using a mutually reactive copolymer resin as an adhesive layer and can be used It is easily separated from the adherend by heating at over 180 ° C, and provides a method of manufacturing an FPCB using the foamed sheet. Another object of the present invention is to provide a method of manufacturing an FPCB which is compared with a conventional manufacturing sheet. The FPCB method enables the production of two single-sided FPCBs in a single process, thereby increasing the productivity of the FPCB manufacturing process by using a double-sided foamed sheet that is used during the hot pressing process, even at 160 The adhesion is maintained at ° C and 40 kg/cm 2 and over 40 minutes under high temperature and pressure conditions, and the double-sided foamed sheet is chemically resistant and is not penetrated by the etchant liquid during the etching process. <Technical means> The present invention relates to a foamed sheet which can be used for an FPCB at a high temperature, which has excellent adhesion strength by using a mutually reactive copolymer resin as an adhesive layer and can be over 180° C is heated and easily separated from the adherend; the present invention also relates to a method of manufacturing an FPCB using the foamed sheet. Hereinafter, a method of manufacturing a foamed sheet which can be used for an FPCB at a high temperature and a method of manufacturing an FPCB using the foamed sheet will be described in detail. For the method of manufacturing an FPCB, a method of manufacturing a one-sided FPCB and a method of manufacturing an FPCB by attaching FPCBs to both sides of a foamed sheet will be described next. The foamed sheet for high-temperature foaming of the present invention is an adhesive sheet in which an adhesive resin mixed with a mutually reactive copolymer containing heat-expandable microspheres is used to form an adhesive layer 8 200922407, and when the layer is adhered to When foaming or swelling is caused by heating, it can be separated at a temperature. 1 is a cross-sectional view showing a single-sided foamed sheet for producing a single-sided foamed sheet, and FIG. 2 is a cross-sectional view showing a double-sided foamed sheet for manufacturing FPCBs by FPCBs are attached to both sides of the foam board. As shown in FIG. 1, in a single-sided foamed board according to the present invention, a substrate 1, a surface treatment layer 2, an adhesive layer 3, and a release film 4 are sequentially stacked, and the adhesive film is adhered. Layer 3 contains heat-expandable microspheres and a mutually reactive copolymer. The beta substrate 1 may comprise a suitable commercial film (such as PET) and has a thickness of preferably less than 250 microns and preferably 25 to 1 micron, but is not limited thereto. this. The surface treatment layer 2 which forms a strong chemical bond between the substrate and the adhesive layer is formed by chemical surface oxidation treatment on the substrate 1, such as chromic acid, ozone, corona (c〇r〇na), flame And treatment with free radiation, or treatment of high polarity polymer compounds such as hydrolyzed ethylene acetyi and polyvinyl butyral on the substrate. The surface treatment layer 2 must not contaminate the adherend when it is separated after heating, and is not changed by the chemicals used during the process of manufacturing the FPCB or under the forming conditions. The surface treatment layer has a thickness of less than 5 microns, and preferably less than 1 micron. The thicker surface treatment layer thickness results in less adhesion layer deformation and less adhesion reduction after heat treatment of the foamed sheet. The surface treatment layer has the following effects: when the heat-separable adhesive sheet is adhered to the adherend, a good surface shape is maintained and a large area is provided, and at the same time, the heat-transfer or the adhesive sheet is heated. The adhesive sheet is separated from the adherend, reducing the restriction of foaming or expansion of the surface of the adhesive sheet and improving the wavy deformation of the adhesive layer. In the case where the 200922407 «Haifa/Package layer is directly coated on the substrate to form a foamed sheet, if the adhesive layer and the substrate of the substrate exist (four) force, the foam layer and the substrate are They will separate from each other when foaming and expanding. Therefore, it is impossible to achieve the desired purpose. The adhesive layer 3 contains heat-expandable microspheres to easily separate the adhesive sheet adhered to the adherend by heating from the adherend. By heating the adhesive layer, the heat-expandable microspheres are foamed and expanded to cause perforation of the adhesive layer. Therefore, the adhesion area of the adhesive layer contacting the adherend is reduced, so that the adhesive sheet can be separated. The heat-expandable microspheres are a material such as isobutane, propane and pentane which are easily vaporized and have thermal expansion, and the outer shell is composed of suitable materials such as a vinylidene chloride and an acrylonitrile copolymer. The suitable material f is heat secreted or can be broken by thermal expansion. The microspheres having an average particle diameter of 10 to 25 μm help to disperse into the adhesive resin by heating, and cause a large deformation of the adhesive layer and a marked decrease in adhesion. Further, the thickness of the adhesive layer formed is greater than the average particle diameter of the microspheres, preferably greater than the maximum particle diameter of the final microspheres. Further, it is preferred to make the surface of the adhesive layer smooth and achieve a stable adhesive force before heating. In order to reduce the adhesion of the adhesive layer by heating, the heat-expandable microspheres are preferably foamed and expanded at a volume/expansion ratio of more than 1 G times, and have such that the heat-expandable microspheres do not expand at the volume expansion ratio. Will break the strength. In addition, since the high temperature of i6 (rc is necessarily required in the process of manufacturing FpcB, it is preferred to use microspheres having a foaming temperature as high as possible. - The content of the heat-expandable microspheres is in accordance with the desired expansion ratio of the adhesive layer. Or the desired degree of adhesion reduction is suitably determined, but generally less than 5Q parts by weight, preferably from $200922407 to 2 parts by weight, based on (10) weight of the wire-forming transition resin. The layer can utilize heat-expandable microspheres that begin to foam under one thief: heating in the temperature range of m to bribe in the FPCB manufacturing process must increase the foaming temperature by limiting the expansion of the microspheres. The mutually reactive copolymer of the layer is an adhesive resin, wherein the first copolymer is obtained by copolymerizing a vinyl monomer 'ethylene comonomer and a vinyl monomer containing a county, the second The copolymer is obtained by copolymerizing a vinyl monomer, an ethyl ketone comonomer and a oxazoline group-containing vinyl monomer. The vinyl monomer constituting the first copolymer and the second copolymer is used. Vinyl comonomer is used to impart adhesion to the adhesive The purpose of force, cohesion 'heat resistance, flexibility, retention, elasticity, etc., if desired, and may be independently selected from one of the following: one or more ethylenic monomers containing a burn group, Selected from methyl acetonate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl acrylate, butyl acrylate, butyl methacrylate, hexyl acrylate, Hexyl methacrylate, octyl acrylate and 2-ethylhexyl acrylate; one or more hydroxyl-containing ethylene monomers 'selected from propyl vinegar via ethyl vinegar, methyl acrylate acid via ethyl vinegar , propyl propyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, f-propyl acrylate, butyl ester hydroxyhexyl acrylate and hydroxyhexyl methacrylate; one or more N_ substituted guanamine vinyl monomer selected from N,N-dimethyl acrylamide and n,N-dimethylmethyl propyl decylamine; one or more stearyl acrylate vinyl monomers Body selected from methoxyethyl acrylate, methoxyethyl methacrylate, ethoxyethyl acrylate and methyl propyl Ethyl ethoxide ethyl ester; one or more vinyl monomers selected from the group consisting of vinyl acetate, vinyl propionate, N-vinyl, pirone, methyl vinyl oxime 200922407 ketone, B Pyrithione, vinylpiperidone, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrazine, vinylimidazole, ethylidene, Ethyl carbaryl, N-ethylene carbamide, styrene, α-methyl styrene and N-ethylene decyl decylamine; one or more cyanoacrylic acid oxime monomers, selected From acrylonitrile and methacrylonitrile; one or more epoxy-containing acrylic monomers selected from glycidyl acrylate and glycidyl methacrylate; or a plurality of ethylene glycol propylene A dilute acid ester monomer selected from the group consisting of polyethylene glycol acrylate, polyethylene glycol methacrylate, polypropylene glycol acetoacetate, polypropylene glycol methyl propyl phthalate, methoxy ethylene glycol acrylate, hydrazine Oxypolyethylene glycol methacrylate, methoxypolypropylene glycol acrylate and decyloxy polypropylene glycol methacrylate; one or more propylene The acid vinegar monomer is selected from the group consisting of tetrahydrofurfuryl acrylate "tetrahydrofurfuryl methacrylate" and methoxyethyl acrylate; one or more monomers selected from the group consisting of isoprene and butadiene , isobutylene and ethylene hydrazine; or a mixture of two or more of the foregoing. The carboxyl group-containing vinyl monomer of the first copolymer is used for the purpose of imparting crosslinking property by radical polymerization, and examples thereof include 2, 3 or more copolymers selected from monofunctional monomers' The functional monomer is, for example, one or more selected from the group consisting of acrylic acid, methacrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, and croton. a carboxyl group-containing monomer of an acid; and one or more anhydride monomers selected from the group consisting of maleic anhydride or itaconic anhydride. The first copolymer is preferably a weight ratio of a vinyl monomer, an ethyl bake comonomer, and a mercapto group-containing vinyl monomer in the range of i: 〇.5 to L5: 〇.〇5 to 〇.3. Manufacturing. The oxazoline group-containing vinyl monomer of the second copolymer is used for the purpose of imparting crosslinking property by radical polymerization, and an example of the oxazoline group-containing vinyl monomer 12 200922407 contains 2 -vinyl·2-oxazoline, 2-vinyl-4-vinyl-2-oxazoline, 2-vinyl-5-ethenyl-2-pyroxyline, 2-isopropylindole -2-°°°Chenlin, 2-isopropyldecyl-5-ethyl-2-oxazoline, 2-isopropenyl-5-mercapto-2-oxazoline, 2-(vinylbenzyloxy) -1-methylethyl)-2-oxazoline, 2-(2-hydroxy-1-indolylethyl) acrylate and 2-(2-hydroxy-indole-methylethyl)methyl propyl Dilute vinegar, or a mixture of two or more of the foregoing. The second copolymer is preferably produced from a vinyl monomer, a vinyl comonomer, and a oxazoline group-containing vinyl monomer in a weight ratio of 1:0.5 to 1.5:0,05 to 0.3. The coating liquid for the adhesive layer of the foamed sheet of the FPCB of the present invention is obtained by dispersing the microspheres to the first one after separately preparing the first copolymer containing a carboxyl group and the second copolymer containing an oxazoline group It is prepared in an adhesive resin obtained by mixing a copolymer and a second copolymer. The coating liquid prepared for the adhesive layer is stable, although the long-term storage at room temperature does not produce a significant change, and the foaming temperature can be increased up to the coating liquid of the conventional foamed sheet. 1 〇 to 3〇t:. The adhesive layer must not be foamed or thermally deformed for 40 minutes at a temperature of 16 01 and a pressure of 40 kg/cm 2 , and is chemically resistant to chemicals that contact the adhesive layer during the manufacturing process of FpCB, and The FPCB will not be contaminated by the transfer of the adhesive resin during the manufacturing process of the FpCB. Furthermore, the adhesive layer must be easily foamed in a pair of flow ovens for 5 to 1 minute at a temperature of 17 to 190 C or in a heating plate for 1 to 3 minutes, which is completed in the manufacture of FpCB. Heating conditions that are easily separated from the adherend after the process. Meanwhile, as shown in FIG. 2, in the double-sided foamed board according to the present invention, a release film 4, an adhesive layer 3, a surface treatment layer 2, a substrate, and a surface are sequentially stacked. The treatment layer 2, the adhesive layer 3 and the release film 4, and the adhesive layers 3 and 3 comprise a heat-expandable 13 200922407 microsphere and a mutually reactive copolymer. The details of each component are the same as for a single-sided foaming plate for FPCB. A method of manufacturing an FPCB using the foamed sheet of the present invention will be described below. The use of a single-sided foam board to manufacture a single-sided FPCB is carried out by laminating FCCL and foaming board, deburring, laminating a dry film, exposing, developing, developing, separating, separating, drying, drying, laminating, laminating, laminating, laminating A punch is processed to separate the foamed sheet. At the same time, a method for manufacturing an FPCB by attaching FPCBs to a double-sided foamed sheet is also carried out, as described above, by the following steps: laminating FCCL and foaming sheet, deburring, laminating a dry film - exposure-development The __ button is used to separate the dry film - the label is bonded to a hot pressed surface treated by a punching to separate the foamed sheet. However, in the step of laminating the FCCL and the foamed sheet, a double-sided foamed sheet is used to laminate the FCCL to both sides of the foamed sheet, so that both sides of the adhered FCCL can be simultaneously processed, and then the rest step. Therefore, by separating the foamed sheets, two single-sided FPCBs can be simultaneously manufactured in a single process. <Advantageous Effects> The present invention can provide a method of manufacturing an FPCB using a foamed sheet which maintains adhesion and chemical resistance even under high temperature and high pressure during a hot pressing process in an etching process It is not penetrated by the etchant liquid during the period and can be easily separated from the adherend by heating at a high temperature. The above described objects, features and advantages of the present invention will become more apparent from the aspects of the appended claims. 14 200922407 <Best Mode> Hereinafter, the foamed sheet for fpcb of the present invention, which uses a mutually reactive copolymer resin as an adhesive layer, has excellent adhesive strength and can be overgrown by fresh, with reference to the accompanying drawings The heat treatment of c is easily separated from the adherend, and a method of manufacturing the FPCB using the foamed sheet. However, this specific embodiment is for illustrative purposes only, and the scope of the invention is not limited thereto. [Manufacturing Example 1] Production of First Copolymer In a 2 liter glass reactor towel equipped with a stirrer, a condenser, a dropping funnel, a thermometer, and a refreshing package, '45 g of a monomeric glyceryl acetoate was used. 45 grams of butyl acrylate as a comonomer and 1G gram of bupropion acid mixed, and _ step - with the addition of grams of α, α, _ azobisisobutyronitrile (as initiator) and 1 〇 Acetate ethyl acetate and 2 g of toluene were then subjected to free radical polymerization. After 3 () minutes, propylene was added and mixed with 135 g of n-butyl acrylate and propylene as a comonomer. 0.5 g of α,α'-azobisisobutyronitrile as an initiator was dissolved in (10) g of guanidine and 40 g of the nail, and then the resulting solution was added dropwise using a dropping funnel for about 90 minutes. The temperature was kept constant during the dropwise addition. In order to eliminate the residual early body after the completion of the reaction, 1 g of the radical initiator was dissolved in 5 g of ethyl acetate and 5 g of ethanol and then added dropwise for 60 minutes, followed by a further reaction for 3 hours. A first copolymer was obtained. The second copolymer was produced in a 2 liter glass reactor equipped with a stirrer, a condenser, a dropping funnel, a thermometer and a jacket, and 45 g of monomeric ethyl citrate and 45 g were used as a monomer. 15 of comonomer 200922407 = mixed with butyl vinegar and ... isopropyl dichloride 2 side. will. 〇ι克 as y, - azobisisobutyronitrile is dissolved in (10) g of ethyl acetate (tetra) such as gram of toluene and then added to the reactor, and the same method is used to carry out the polymerization of the copolymer containing m-group. ...to carry out free radical polymerization. After 30 minutes, σ 135 grams of ethyl acetoacetate, gram of propylene as a comonomer, and 30 grams of acrylic acid were added. A 5 · azobisisobutane as an initiator was lightly dissolved in 4 g of toluene acetic acid, and then the bath was added dropwise using a dropping funnel for about 90 minutes. Maintain temperature mosquitoes during dripping. In order to eliminate residual monomers after completion of the reverse bank, the gram free radical initiator is dissolved in % gram of ethyl acetate and 50 grams of ethanol and then added dropwise for a period of (9) minutes, followed by a further reaction for 3 hours. Second copolymer. Production of Adhesive Resin The first copolymer and the second copolymer produced by the above were mixed in a ratio of 1:1. H) gram microspheres (product name: F8GVSD, available from Matsumoto Oil & Fat Pharmaceutical Co., Ltd.) were prepared by mixing the resin under the (9) thief and adding it to the mixed resin of (10)^, thereby producing an adhesive resin. [Manufacturing Example 2] An adhesive resin was produced in the same manner as described in Production Example 1, except that the weight ratio of the monomers used in the production of the first copolymer and the second copolymer was each acrylic acid/acrylic acid. N-butyl vinegar / acrylic acid = 4.5 / 4.5 / 1.5 and ethyl acrylate / n-butyl acrylate / 2-isopropyl dilute - 2 ° 唆 唆 = = 4.5 / 4.5 / 1.5. [Manufacturing Example 3] The adhesive resin was produced in the same manner as described in the production example 1, except that the weight ratio of the monomers used in the first copolymer and the second copolymer of 16 200922407 was each ethyl acrylate/n-butyl acrylate/ Acrylic acid = 4,5/4.5/0.6 and ethyl acrylate/n-butyl acrylate/2-isopropylidene-2-° oxalate = 4.5/4.5/0.6. [Manufacturing Example 4] by manufacturing The adhesive resin was produced in the same manner as described in Example 1, except that the monomer used in the manufacture of the second copolymer of Production Example 1 was 2-ethylhexyl acrylate/ Methyl methacrylate / n-butyl acrylate / 2 - isopropenyl 2 - oxazoline = 2.0 / 2.5 / 4.5 / 1.0 [Production Example 5] Adhesion was produced in the same manner as described in Production Example 4. Resin, but the weight ratio of the monomer used in the manufacture of the second copolymer of Example 4 was 2-ethylhexyl acrylate / methyl methacrylate / n-butyl acrylate / 2 - isopropenyl 2 - oxazole Porphyrin = 2.0 / 2.5 / 4.5 / 1.5 [Examples 1 to 5] The adhesive resin manufactured in Production Examples 1 to 5 was applied to a polyethylene terephthalate film (PET film) (5 μm) A 37 micron foamed adhesive layer was formed thereon, and a 36 micron release film was attached thereto to fabricate a foamed sheet, and then the foamed sheet was aged for 7 days. By attaching FpCbs to The entire process for making single-sided FPCBs on both sides of the foamed sheet is carried out by laminating FCCL and foamed sheet - deburring - laminating dry film - exposure - developing - etching - separating the dry film - label bonding - heat Press-surface treatment—punching—separate the foam board. Next, evaluate the performance of each step. A.FCCL Choice 17 200922407 In general, FCCL for single-sided FPCB is classified by the thickness of copper foil, adhesive, polyimide film and the type of copper foil. In the current embodiment, the use table has The copper foil of the specification shown in 1. The cover film used in the manufactured product has a thickness of 25 μm in the adhesive layer and a thickness of 25 μm in the polyimide layer. [Table 1] Thickness of the sample manufacturer PI Thickness of Copper Thickness Copper Type Total Thickness Sample 1 Hanwha L&C 25 μm 15 μm l/2oz Electrolytic Copper (ED) 57.5 μm B. Lamination (FCCL and Foam Board) In this step, the layer is bursting The bubble board and FCCL are used to adhere the FCCL to the foam board. The lamination is carried out by using a general laminating machine in which the copper foil of the one-sided FCCL faces outward and the surface of the polyimide is adhered to the foamed sheet. Avoid the generation of bubbles and wrinkles of polyimine in the adhered product, and determine the adhesion state of the surrounding parts, so that in the subsequent steps, various chemicals will not penetrate into the adhered by the adhesion at the periphery. product. C. Deburring In the deburring step, the rust inhibitor coated on the surface of the copper foil to prevent corrosion of the surface of the copper foil is removed, and unevenness is generated on the surface of the copper foil to increase the surface area of the copper foil and increase the dryness. The adhesion of the film (photosensitive resin). This step was carried out via the surface of a slightly oxidized copper of the chemical method, and a mixed solution of sulfuric acid (H2S〇4) and hydrogen peroxide (H2〇2) was used as the chemical. D. Laminated dry film Dry film lamination is a step of adhering a photosensitive resin to a copper foil to form electricity on the copper foil. When manufacturing a single-sided FPCB, a dry film is laminated on the surface of the copper foil, and since the FCCL is thin, the surface of the opposite side polyimide is attached to a carrier film to prevent wrinkles in subsequent steps. Or tear. E. Exposure In the exposure step, when ultraviolet light (UV) is irradiated to form a photomask film placed over the FCCL to which the photosensitive resin is adhered to form a circuit, the UV cannot transmit the dark portion of the photomask film and can only The transparent portion of the reticle film is transmitted. Therefore, the crosslinking action only occurs when the dry film has a portion that receives UV. F. Development The dry film was exposed to a 3% sodium carbonate solution. As a result, the portion which received UV to cause cross-linking was not dissolved, but the portion which did not receive UV and which did not undergo cross-linking was dissolved to expose copper. G. Etching the dry film as a resist by covering the copper foil at a portion where the circuit is formed by development, and applying an etchant (CuCl2, HCl, H2〇2) to the exposed copper foil to erode the circuit The rest of the copper foil. The chemicals and processing conditions used in the individual steps are summarized in Table 2. [Table 2] Program detailed procedure chemical temperature time mode to form circuit deburring h2so4, h2o2 solution 25 to 28 ° C for about 20 seconds spraying to remove the copper surface to develop the dry film Na2C03 solution 30 to 35 ° C for about 30 seconds Dissolved photocurable resin surnamed CuCl2, HC Bu H2〇2 38 to 42 ° C Sprayed rotted copper surface for about 60 seconds 200922407 Η·Label bonding After etching to form a circuit in FCCL, to protect the circuit, The cover film is adhered to a circuit portion other than the portion to be connected to the connector and the portion to be used for mounting parts. Since the cover film is coated with a thermosetting adhesive, the adhesion is weak. Therefore, before the curing of the adhesive by hot pressing, the cover film and the circuit-formed FCCL are partially and temporarily fixed by welding to prevent the cover film from moving. I. Hot pressing Hot pressing is to adhere the cover film by thermosetting and is carried out under the conditions shown in Table 3. In this step, the heat and pressure strips are used to heat the adhesive of the cover film over a predetermined period of time. In order to use the foamed sheet, the foamed sheet must be unfoamed under the processing conditions of this step, and the foamed sheet and the FPCB must be free from deformation or dimensional change of the outer shape. [Table 3] Equipment Mode Type Processing conditions Pressure Temperature Time Younshin H/P Foam board test Double-sided 51 kg / cm ^ 2 160. . 105 minutes J. Surface treatment Surface treatment was generally carried out using electroless plating, and the electroless plating method was carried out in batch mode under the conditions shown in Table 4. Gold plating is a complex procedure and the pre-steps of using the chemicals listed in the table below are performed prior to gold plating. [Table 4] Program detailed procedure Chemical temperature time mode effect Gold plating cleaning surfactant 36 to 40 ° C About 3 minutes deposition to remove oxide layer and clean 20 200922407 Activate PdCl2, HC1 solution 25 to 28 ° C About 3 minutes deposition Copper-plated nickel (Pd) instead of PCB is plated with NiCl2, h2po2, and the wrong agent is 80 to 90 ° C for about 10 minutes to deposit electroless nickel plating acid deposition H2S〇4 25 to 28 ° C for about 4 minutes to deposit acid-treated gold plating Overlay K[Au(CN)4] 80 to 90°C for about 8 minutes to deposit electroless gold plating κ. Form external shape (punching) To complete the final product, it will be punched with fpcb processed by attached foam board The holes form an outer shape. At this time, the guide holes are precisely mounted according to the position of the mold to form an outer shape. L. Separating the foamed sheet - · · · · - - In this step, the FPCBs attached to both sides of the foamed sheet must be separated. The foamed sheet is characterized in that it is separated by a decrease in adhesion caused by expansion of the foaming chamber at a predetermined temperature. The foaming temperature has been designed such that the foamed sheet is foamed at at least 170 °C. The finished surface treated product is separated by a heating device such as a convection oven. [Comparative Production Example 1] In a 2 liter glass reactor equipped with a stirrer, a condenser, a dropping funnel, a thermometer, and a jacket, 48.5 g of n-butyl acrylate, 48.5 g of ethyl acrylate, 2 g of acrylic acid, 1 Hydroxypropyl acrylate and hydrazine. 1 g of α,α'-azobisisobutyronitrile was dissolved in 160 g of ethyl acetate and 270 g of toluene, and then added to a dropping funnel, followed by replacement with nitrogen. In a continuous flow, radical polymerization was carried out for 8 hours while dropping at 80 °C. At the end of the reaction, an excess of free radical initiator was added to eliminate residual monomer, and then 10 g of microspheres were added (product name: F80VSD, available from Matsumoto Oil & Fat Pharmaceutical Co., Ltd., starting at 150 to 160 ° C) Foaming and dispersing, and then adding sesame & isophthalate crosslinker (product name: AK-75, Aijing Chemical Co., Ltd.) and stirring with an amount of twice the hydroxyl functional group in the adhesive 21 200922407 resin The article, the & article, thus produced the adhesive resin. [Comparative Production Example 2] An adhesive resin was produced by comparing the phase-inducing method described in Production Example 1, but the amount of the acrylic acid having a cross-linking functional group was increased to 2 g by the amount of the propyl ester. [Comparative Production Example 3] An adhesive resin was produced by, for example, comparing the relative phase method described in Production Example 1, but an isocyanate crosslinking agent was added by using a hydroxyl functional group content in the adhesive resin (product name: AK-75, Ai Jing Chemical Co., Ltd.). [Comparative Production Example 4] An adhesive resin was produced in the same manner as described in Comparative Production Example 2, but an isocyanate crosslinking agent was added in four times the content of the hydroxyl functional group in the adhesive resin (product name: AK-75) , Ai Jing Chemical Co., Ltd.). [Comparative Examples 1 to 4] ''Working by applying an adhesive resin manufactured in Production Examples 1 to 4 onto a 叩T film (50 μm), forming a 37 μm foamed adhesive layer thereon' and attaching A % micron release film is fabricated thereon - a foamed sheet. The fabricated foamed sheet was aged for 7 days and then used for final testing. By attaching FpCBs to both sides of the foamed sheet, the entire process of making the single-sided FPCB was carried out by the following steps: laminating FCCL And the hair/bundle to the burr, a laminated dry film, an exposure-developing-etching-separating the dry film-domain bonding-hot pressing-surface treatment-punching-separating the foaming plate. Next, evaluate the performance of each step. In order to test the method of manufacturing a single-sided FPCB by attaching FPCBs to both sides of a foamed board using the above-described manufacturing examples, comparative manufacturing examples, examples, and comparative examples of adhesive resins and foamed sheets manufactured by 22,022,407, The reliability of the foamed sheet for temperature-foaming was evaluated for each step of manufacturing the FPCB under the following materials and processing conditions. 1. Selection of Unprocessed Sheets For the manufacture of FPCBs, the unprocessed sheets used for the foamed sheets are designed such that the foaming agent is foamed to an optimum volume at at least 180 °C. Therefore, a PET film having a thickness of 25 to 1 μm is used since it is necessary to maximize heat transfer at the time of foaming and must have flexibility in consideration of workability or a roll method. In addition, there must be no thermal change in size due to repeated heating to . and gentle cooling to room temperature. In order to meet this condition, a substrate having a thickness of 50 μm and a release film having a thickness of 36 μm were used. 2. Conditions and Methods of Foaming Generally, a convection oven and a heating plate are used to separate the foamed sheets. A foamed sheet having a minimum width of more than 250 mm is used in the manufacture of the FPCB, and since the foamed sheet must be durable in the hot pressing step, the blowing agent itself should have physical properties of high foaming temperature. Therefore, the foamed plate separating apparatus is selected in consideration of the heat transfer efficiency in accordance with the desired foaming power and the size change of the FPCB. 3. Evaluation of Reliability Apply the foam board to the method of manufacturing a single-sided FPCB, and then confirm whether it is possible to manufacture the FPCB by attaching the FPCBs to both sides of the foam board to double the process efficiency and reduce The thin thickness of the FPCB causes wrinkles or tears in the manufacturing process. In particular, when using the foamed sheet, it is additionally tested whether the foamed sheet itself will improve the quality of the FPCB, and whether the process of manufacturing the FPCB will produce negative factors to reduce productivity and produce undesirable products. The temperature was maintained at 70 ° C and FCCL was laminated to both sides of the foamed sheet. During the lamination step, bubbles and wrinkles of polyimine are not produced in the adhered product. In particular, the adhesion state of the surrounding portion is determined, so that various chemicals do not penetrate into the adhered product due to a decrease in adhesion at the periphery, and the result shows a strong adhesive force. Even when the foamed sheet to which the copper foil was adhered was bent in the roll, the separation of the foamed sheet from the copper foil was not observed. The chemical used for deburring was a mixed solution of sulfuric acid (h2so4) and hydrogen peroxide (h2o2), and it was confirmed that the solution did not penetrate into the surface of the foamed sheet. In this step, the thickness can be maintained when the FCCLs are attached to both sides of the foamed sheet, so that a carrier film is not required, and the carrier film is a secondary material. Further, it was confirmed that the work procedure was lowered to 50% because the dry film was laminated to both sides at the same time. Further, it was confirmed that the exposure machine irradiated UV from the front and the back to simultaneously expose both sides in the exposure step, and since both sides were simultaneously exposed when the exposure step was performed using the foamed plate, the productivity was doubled. The FCCLs separation procedure, which was carried out by attaching FCCLs to both sides of the foamed board, has confirmed that the quality of the product will not be affected and that the ease of processing can be improved. In the developing step, no separation phenomenon due to penetration of the developer (Na2C03) was observed. In the etching step, similar to the developing step, there is a possibility that the FCCL and the foamed sheet are separated due to the penetration of the strong acid solution, but the separation phenomenon was not found in actual tests. In the label bonding step, an iron is used and an iron is also used when processing using the foamed sheet. Therefore, it is necessary to prevent the foamed sheet from being foamed by the iron, and it is confirmed that partial foaming does not occur after the label bonding step. In order to confirm the dimensional stability during the hot pressing step, the dimensions of the product manufactured and used without using the foamed plate 24 200922407 are measured using a three-dimensional measuring device. The target value for dimensional stability is set to be less than 0.03%. The separation of the foamed sheet due to the penetration of chemicals is an important problem in electroless plating (i.e., surface treatment steps). In the electroless plating step in the present invention, a chemical treatment of a deposition method is used and the result of visual testing confirms that the liquid does not permeate. In this step, the FPCBs attached to both sides of the foamed sheet should be separated. The foamed sheet is separated by the expansion of the foaming chamber at a predetermined temperature to cause a decrease in adhesion. The foaming chamber is designed to foam at at least 170 °C. The finished surface treated product is separated using a heating device such as a convection oven. The certification factors required for a fully separated FPCB are described below. First, the adhesive of the foamed sheet should not be transferred to the back side of the FPCB. Second, no wrinkles on the product should be produced during the foaming and separation steps. Third, in the entire procedure for the use of such chemicals, the foamed board should avoid contamination by liquid penetration. In fact, the wrinkles on the product are produced after the foaming of the foaming chamber having a non-uniform particle size in the foamed sheet. However, by making the particle size and particle size distribution of the foamed sheet uniform, a final product having the same quality as the conventional one using a single-sided foamed sheet can be produced. Table 5 shows the results of applying the samples obtained by the examples and comparative examples to the method of manufacturing the FPCB. [Table 5] \Sample Step \ Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Good lamination Good Good Good Good Good Good Good Good Good deburring Good Good Good Good Good Good Good good lamination dry film good good good good good good good good good good exposure good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good good 25 200922407 separation dry film Good, good, good, good, good, good, good, good, good, good, good, good, good? ^ ----^ Good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good, good ) ί unfoamed > (foaming separation) (foaming separation) (foaming separation) (foaming separation) good surface treatment good good good good - - - - good punching good good good - _ good - - - - Separation of foamed board is good (foaming separation) Good (foaming separation) Good (foaming separation) Good (foaming separation) ---- Good (foaming separation) - - - - To confirm the hot pressing step Dimensional stability, using a three-dimensional measuring device to measure the size of a product manufactured using the foamed sheet and the size of a product manufactured by using a single-sided foamed sheet by an existing method. As shown in the fourth and fifth figures, The measured result shows that the rate of dimensional change is less than 〇.Q3.., which is the target value of dimensional stability. This means that the dimensional problem does not affect the manufacture of the product when the foamed sheet is processed. The side of the FPCBs is manufactured by attaching FPCBs to both sides of the foam board. In the process, various chemical industries are added during the manufacturing process to confirm whether the adhesive of the foamed board is dissolved in the chemicals used and penetrated by the chemicals used by the household. If the adhesive is dissolved and penetrated, It is impossible to carry out the procedure for separating the foamed sheet from the FCCL due to the decrease in the adhesive force of the adhesive, and it is possible to cause contamination of the FCCL due to the penetration of the liquid. However, the foamed sheet of the present invention does not cause a cause. Quality problems caused by the penetration of chemicals (such as etchant liquids, etc.) and, from Table 6, the productivity can be confirmed by attaching FPCBs to single-sided FPCBs on both sides of the foamed sheet. [Table 6] Program Description Effect Laminated Foam Board - Laminated FCCL and Foam Board to Process FCCL by Attaching FCCLs to Both Sides of Foam Board Work Procedure Add 100% Laminated Dry Film - Simultaneously laminating both sides - attaching the carrier film to the back when working with a single-sided foam board reduces the working procedure to 50°/〇 without the carrier film 26 200922407 1 - no carrier film is required when using the foamed board 1 ~~ ~~~- Exposure - Exposing both sides simultaneously when using a foam board - Development - Simultaneous development of both sides when using a foam board <rw/ money copper - can be used on both sides of the rotted copper 1 working disk drop and f 叩〇 / P away from the dry film when the foam board is used - the dry film can be simultaneously separated on both sides when the foam board is used - 1~ Dry Can 1 - It is possible to simultaneously dry both sides of the π while using the foam board. / Remove carrier thin m. Unused work procedure when using foamed board. 〇〇% • Reduce wrinkles and tears when removing the load-bearing film - This step is by attaching FCCLs to The working procedure on both sides of the foam board is reduced by 〇%... The same processing time is used when processing FCCL compared to when using single-sided foam board •μμ • The mounting amount is increased by 3〇% by attaching FCCLs to both sides of the foam board Increased loading of secondary material paste f by 50% - used to reduce the amount of secondary material used to process FCCL to 50% by attaching FCCLs to both sides of foamed sheets (PVC thin, PET film and air-cushion film)__ ^^ Simultaneously, the deburring is reduced to 50% at the same time. - When using the hair/packing plate, the surface treatment of both sides is simultaneously reduced by i_ 50%. The separation of the foaming plate is removed by attaching rccLs to the foaming plate. Adding on both sides to the |Wei program increases by 1〇〇0/. Products made by FCCL: ~ Warfare guide hole - the procedure for forming the guide hole is the same as the one using the single-sided foam plate processing ^~ The outer part is formed into the external shape and the single-sided foam is used. When the board processing is the same, the same final product program and the single-sided foam board are added 1 - (4) <Industrial Applicability> As described above, according to the present invention, it is possible to provide a method for manufacturing an fpcb using a foamed sheet to maintain the adhesion and chemical resistance under high temperature and high pressure during a hot pressing process. During the (4) procedure, * will be infiltrated by the (four) agent liquid and separated from the adherend by high temperature heating. Further, in the present invention, the two-sided FPCB can be produced in a single process and the productivity of the FPCB manufacturing method can be improved as compared with the conventional method of manufacturing a single-sided FPCB. BRIEF DESCRIPTION OF THE DRAWINGS 27 200922407 Fig. 1 is a cross-sectional view showing a single-sided foamed sheet of the present invention; and Fig. 2 is a cross-sectional view showing a third graph of a double-sided foamed sheet of the present invention. The processing conditions for hot pressing used in the present invention are shown; Fig. 4 is a graph showing the rate of dimensional change when processing using the foamed sheet of the present invention; and Fig. 5 is a graph showing the use of conventional single-sided foaming The rate at which the dimensions change during sheet processing. [Description of main component symbols] 1 Substrate 2 Surface treatment layer 2' Surface treatment layer 3 Foamed sheet 3' using a mixture of mutually reactive copolymers Foamed sheet 4 using a mixture of mutually reactive copolymers Release film 4' Release film 28