diff --git a/tiny_obj_loader.cc b/tiny_obj_loader.cc
index 3f4cfc5..323573d 100644
--- a/tiny_obj_loader.cc
+++ b/tiny_obj_loader.cc
@@ -555,7 +555,8 @@ std::string LoadMtl(std::map<std::string, int> &material_map,
     }
     if (token[0] == 'T' && token[1] == 'r' && isSpace(token[2])) {
       token += 2;
-      material.dissolve = parseFloat(token);
+      // Invert value of Tr(assume Tr is in range [0, 1])
+      material.dissolve = 1.0 - parseFloat(token);
       continue;
     }