Muon radiography is nondestruction research technic for large structure like a pyramid, volcano, blast furnace. The technology measures the density length (=material density × path length) by calculating penetration rate of muon flux. The nuclear emulsion that is made in Nagoya university detects number of muon tracks and angles. We tried to change its “plastic layer” to thick type for improvement of angular accuracy and estimated “long term performance” and “angular accuracy”. In conclusion, the candidate has same long term quality and higher angular resolution.