diff --git a/bashrc b/bashrc
index d049610..da1902b 100755
--- a/bashrc
+++ b/bashrc
@@ -742,7 +742,8 @@ di(){
 }
 
 tb(){
-    local tb="$HOME/.my/tb"
+    local datenum=`date +%Y%m%d-%H%M%S`
+    local tb="$HOME/.my/tb/$datenum"
     mkdir -p "$tb"
     for file in "$@"
     do