조선시대 천연 유성도료 명유(明油)의 전통과 재현 = Tradition of the Natural Oil Paint Myeongyu of the Joseon Dynasty and Reproduction

국문 초록 (Abstract)

본 연구는 조선시대 건물과 가구 등에 마감도료로 칠한 명유(明油)의 사용사례를 밝히고 실제 명유 제작과 그 사용을 통해 조선시대 명유 사용 전통의 복원을 시도하고자 한다. 명유(明油)는 조선조 내내 사용되다 일제 강점기에 그 전승이 끊어지고 현재 사용되지 않고 있는 들기름으로 만든 유성도료로 목조문화재의 보존과 수리과정에 반드시 필요한 것이다. 목조건축물에 옻칠이 잘 사용되지 않는 우리의 전통을 고려하면 명유(明油)가 사용되지 않는 현재의 상황은 우려스러운 일이다. 조선조 내내 해오던 목조건축물 발수도료 도포가 중단된 지 오래되었고 단청과 같은 수성도료로만 최종마감을 하는 것에 만족하고 있다. 이러한 상황이 지속되게 되면 목재가 습기를 흡수해 부후가 빨라지게 되고 목조문화재의 수명은 상당히 단축될 수밖에 없을 것이다.
명유는 조선왕조의궤를 통해 그 사용 범위와 적용 방식을 파악할 수 있다. 조선왕조의궤 중 영건의궤뿐 아니라 국장의궤, 가례도감의궤, 진연의궤 등 거의 모든 의궤가 명유의 사용기록을 남기고 있어 조선시대 유성도료 사용은 매우 보편적인 것이었음을 확인할 수 있다. 명유는 건축물의 내외부 도장, 가구의 도장, 우비, 장례용품, 옻칠 대용 등의 다양한 목적으로 사용되었다. 조선시대 궁궐이나 건물의 단청칠 위에 명유가 어떻게 어느 정도의 범위로 도포되었는지가 밝혀지면 현재의 목조문화유산에 유성도료의 도장이 어떤 방식으로 행해져야 하는지에 대한 정확한 이해가 가능해 질 것이다. 이를 위해 창경궁 문정전의 사례를 살펴보았는데 문정전은 주기적으로 빈전으로 사용되었기 때문에 재도장에 소요된 물품의 양과 재도장 주기, 유성도료인 명유의 재칠 부위를 어느 정도 알 수 있게 해준다. 1720년부터 1730년 10년 동안 문정전의 재도장은 3회 이루어졌는데 매번 외부기둥, 박공, 장지청판 등에는 명유도장이 반복되었다. 내부기둥은 2회 이루어졌다. 건물 외부 비를 맞을 수 있는 부위는 유성도료 도장이 잦고 내부와 비를 맞지 않는 단청부위는 유성도료 도장의 횟수는 적었다. 따라서 현재의 건축문화재의 비를 맞을 수 있는 부위에 대한 유성도료 도장이 제대로 이루어지지 않고 있는 것은 적절한 유지보수 방법이 아닌 것임을 알 수 있다.
조선왕조의궤에 의하면 명유를 제작하기 위해 소요된 물품은 들기름, 무명석(無名石), 황단(黃丹), 백반(白礬)인데 각 물품의 구체적인 사용량이 잘 남아 있기때문에 복원이 어렵지는 않을 수 있다. 그러나 명유의 제조법이 구체적으로 의궤에 남아 있지 않기 때문에 이를 인접 기술에서 원용해야하고 시행착오를 거쳐 복원할 수밖에 없다. 들기름에 무명석과 황단을 넣는 이유는 들기름의 산화로 인한 고분자화를 촉진시키는 건조제로 작용하기 때문이다. 들기름은 공기중의 산소를 끌여당겨 저절로 중합반응을 일으키는 건성유로 도료에 사용되는 식물성 기름중에서 가장 높은 건조성을 가진 건성유이다. 여기에 망간, 납, 철 등의 금속성분이 첨가되면 중합반응이 급속히 빨라지게 되고 결국 액체가 고체가 되어 피막을 만들게 된다. 이와 동일한 속성을 가진 일본과 중국의 건성유(乾性油) 칠의 사례를 살펴보아야 하는데 일본의 경우 들기름에 납성분인 밀타승(密陀僧)을 넣고 끓여 사용한 기록과 서기 7~800년대의 실물이 남아있어 참고가 된다. 중국에서는 동유(桐油)에 무명석과 황단을 넣고 끓여 도료로 사용하는 전통이 지금도 남아 있어 그 제조법을 참고할 수 있다. 들기름과 가장 유사한 성격의 기름은 유화(油畫)에 사용되는 아마씨유 기름으로 그 지방산의 구성성분이 흡사해 제조방식 역시 비슷할 것으로 생각되어 그 끓이는 온도와 지속시간, 첨가물 첨가방식을 적용해 명유를 실제 제조하고 건조성능을 테스트해 보았다.
원료 들기름의 건조시간과 비교할 때 동일한 들기름으로 제조한 명유는 수십 배에서 수백 배까지 빨리 건조하는 속건성을 나타내었다. 이는 서구의 보일드린시드오일보다 건조가 빠른 것이어서 조선시대 사용된 명유도 이러한 속건성을 지녔음을 추측할 수 있었다. 백반은 건조제로 사용되지 않고 끈적임을 방지하는 난연성 첨가제로 작용함을 알 수 있었다.
조선왕조의궤에서 명유는 가칠(假漆)로, 명유를 바르는 장인은 가칠장(假漆匠)으로 불렸는데 이는 옻칠을 진칠(眞漆)로 여기면서 옻칠과 거의 동일한 성격을 가진 칠로 여겼기 때문으로 보인다. 그래서 그릇이나 기물의 칠에서 명유칠 도장은 옻칠과 거의 유사한 방식으로 이루어졌는데 모시베를 바르고 골회와 콩가루로 틈메우기를 한 후 명유와 안료를 혼합하여 바르는 방식을 발견할 수 있다.
이후 대한제국시기가 되면 양명유가 도입되어 사용되고 점차 명유는 사라지게 된다. 명유의 전통에 대한 전승이 사라져 곳곳에서 혼선이 일어나고 있다. 무형문화재 소목장과 칠장은 조선왕조의궤나 『임원경제지(林園經濟志)』, 『규합총서(閨閤叢書)』 등에서 전혀 사용되지 않던 불건성유를 사용하는 전통이 형성되어가고 있다. 조선왕조의궤에는 불건성유를 도료로 사용한 전례가 발견되지 않고 『임원경제지(林園經濟志)』의 경우 건성유인 법제들기름, 호도유가 사용되고 있으며 불건성유 사용은 존재하지 않고 있다.
명유는 강도 높은 피막이 아닌 신축성있는 도막을 만들어 열등한 도료인 것 같이 보이지만 목재에 바르게 되면 수축팽창하는 나무의 성질과 일치해 같이 수축팽창을 하기 때문에 도막이 갈라지거나 들떠 일어나지 않는 우수한 목재용 도료이다. 문화유산의 보존과 유지를 위해 명유에 대한 보다 깊은 연구가 요구된다.

목차 (Table of Contents)

• Ⅰ. 서론 ···························································································································1
• 1. 연구목적 ··················································································································1
• 1) 목조 문화재 보존 유지를 위한 도료의 필요성 ············································2
• 2) 생들기름 도포시 건조지연 문제 해결의 필요성 ··········································3
• 2. 선행연구 및 연구방법 ·······················································································5
• 1) 명유의 전승과 선행연구 ····················································································5
• 2) 명유의 복원연구 ··································································································8
• 3) 연구범위 및 연구방법 ······················································································12
• Ⅱ. 동아시아 유성도료(油性塗料) 사용 전통 ···········································15
• 1. 유칠(油漆)의 사용 기록 ·················································································15
• 1) 동아시아 고대 문헌과 유물에 나타난 유칠의 존재 ··································15
• 2) 조선왕조기록를 통해 본 명유(明油) 사용의 보편성 ································18
• 3) 민간 기록으로 본 유칠(油漆)의 전래 상황 ················································24
• 2. 진칠(眞漆)과 가칠(假漆) ···············································································27
• 1) 가칠(假漆)과 가칠장(假漆匠) ········································································28
• 2) 전칠(全漆)과 매칠(每漆), 농담칠(濃淡漆) ················································32
• 3) 골회(骨灰)와 태말(太末), 탄말(炭末) ························································42
• 3. 중국과 일본의 유칠(油漆) ·············································································55
• 1) 밀타회(密陀繪) ··································································································57
• 2) 일본 고건축물의 유성도료 사용 사례 ··························································66
• 3) 중국의 유칠 작업 ······························································································76
• Ⅲ. 조선시대 건축, 가구, 생활용품의 명유(明油)사용 사례········88
• 1. 단청(丹靑)에 사용되는 명유 ········································································88
• 1) 단청에 사용되는 유칠(油漆)의 범위 ····························································88
• 2) 조선중기에서 근대까지의 궁궐 보수 작업에 사용된 명유 ······················96
• 2. 가구제작에 사용된 명유 ···············································································106
• 1) 취색명유(取色明油) ······················································································112
• 2) 교합명유(交合明油) ························································································133
• 3. 우비(雨備)와 분판(粉板)에 사용된 명유 ············································139
• 1) 유삼(油衫) ········································································································140
• 2) 유둔(留屯) ········································································································145
• 3) 분판(粉板) ········································································································150
• Ⅳ. 명유(明油)의 제조 재연 ············································································155
• 1. 들기름의 건성유(乾性油) 특성 ··································································155
• 1) 건성유와 불건성유 ··························································································158
• 2) 건성유 건조의 화학 ························································································161
• 3) 동유(桐油), 아마(亞麻)씨유와 들기름 ······················································165
• 2. 명유제조 재연 ···································································································171
• 1) 명유제조방식 유추 ··························································································171
• 2) 명유제조 온도와 지속시간 ············································································174
• 3) 무명석(無名石)과 황단(黃丹)의 역할 ······················································177
• 4) 백반(白礬)의 기능 ··························································································186
• 5) 명유 끓이기 ······································································································191
• 6) 명유제조와 가열온도, 지속시간의 변화 ····················································196
• 3. 명유사용 재연 ···································································································200
• 1) 제조 명유의 교합칠(交合漆) 재연 ······························································200
• 2) 단청 표면 명유(明油) 착칠 ········································································202
• Ⅴ. 명유 전통의 단절과 복원의 필요성 ·····················································206
• 1. 명유 사용의 중단 ····························································································206
• 1) 양명유(洋明油)와 호광유(胡光油)의 등장 ················································206
• 2) 들기름 도료 사용의 중단 ··············································································209
• 2. 전통 계승의 문제 ····························································································213
• 1) 소목장(小木匠)과 칠장(漆匠)의 동백기름 사용 ······································213
• 2) 동유(桐油) 사용 전통의 진위 ······································································229
• 3. 건물 유칠(油漆)의 중단과 문제점 ···························································236
• 1) 명유(明油)와 바니시의 차이 ········································································236
• 2) 목조 문화재 방수도료 도포의 필요성 ························································237
• 3) 생들기름 도포와 도포방법 ············································································241
• Ⅵ. 결론 ·······················································································································244
• 참고문헌 ··························································································································251