34 before being dried in a traditional paper making process the paper is impregnated with any one of a variety of sizing resins such as polyvinylalcohol pvoh or gelatin to minimise the uptake of oily substances or organic solvents the paper sheet 14 is passed through a size bath 18 so that it becomes saturated with size the resulting paper is thus resistant to grease and has a lower abosorbency and it is therefore more appropriate for use as banknote paper and the like the paper sheet 14 is then passed through an air float or spar dryer 20 for further drying before passing to a calendering device 21 to give a smooth surface before reeling 22 in the modified process according to the invention a screen printing process or other resin applicator is used to apply a transparentising resin to the surface of the partially formed paper sheet 14 before it enters the size bath 18 this is shown in more detail in fig3 the screen printer 23 is a rotary printer comprising a cylindrical screen 23 of flexible wire mesh mounted on a rigid steel rim covered by a stencil 24 the image required to be reproduced on the paper is formed in the stencil by means of an opening 25 as the paper sheet 14 passes the cylinder the transparentising resin 26 is applied to the inside of the wire mesh and forced through the mesh with a squeegee blade 27 onto the paper sheet 14 at this point the partially formed paper is at.