Cellulose substrates with transparentized area and method of making

A cellulosic substrate which is suitable for use as a mailer or envelope and which has at least one transparentized portion is provided. A method of transparentizing a cellulosic substrate by the application of a transparentizing material which provides enhanced toner adhesion properties, fast penetration rates and which is cured by exposure to radiation is also provided. The addition of small amounts of water to the transparentizing material enhances penetration rates. Further, these transparentizing materials may be applied without the need for solvents. These features thus permit continuous, in-line transparentization.