diff --git a/Source/PPSSignatureView.m b/Source/PPSSignatureView.m
index 9ad6d1e..7535750 100644
--- a/Source/PPSSignatureView.m
+++ b/Source/PPSSignatureView.m
@@ -387,10 +387,12 @@ - (void)setBackgroundColor:(UIColor *)backgroundColor {
         clearColor[0] = red;
         clearColor[1] = green;
         clearColor[2] = blue;
+        clearColor[3] = alpha;
     } else if ([backgroundColor getWhite:&white alpha:&alpha]) {
         clearColor[0] = white;
         clearColor[1] = white;
         clearColor[2] = white;
+        clearColor[3] = alpha;
     }
 }