Abstract: Postcards and reply postcards for confidential purposes of a structure in combination comprising an S- or Z-folding, continuous postcard form having on at least one major side a first region to bear an address and second regions to bear confidential information, one of said second regions being folded back onto the back side of said first region along a line and the other of said second regions being folded back onto said one region along a line on the middle portion of and between said second regions and a Z-folding continuous postcard form is designed for mailing information and a third region being folded back onto said one region along a folding line is designed for a reply, and such postcard form is prepared in a continual form so as to be printed both addresses of the addressees and items of his confidential information at the same time by a printer connected to a computer thereby to ensure the right entry of information and a third region, if any, being printed the addresses and names of addressors and

Abstract: The invention relates to an envelope having a transparent layer, allowing printed information on the letter paper in the envelope to appear through the envelope. The inner surface of the transparent layer is laminated with a transparent, thermal adhering synthetic resin film to bind the transparent layer to a second layer along their periphery.