of solids which ranges from about 25 to about 50 percent solids with 30 to 35 being typical therefore when such emulsions are used the preferred amounts range from about 18 to about 50 without wishing to be bound by theory it is believed that the petroleum wax migrates to the surface of the adhesive thus modifying the initial tack characteristics of the acrylic copolymers which are normally aggressively tacky and non repositionable this migration results in a lowered initial tack for adhesives of the invention thus the adhesive may be removed and reapplied when applied to the substrate lightly however when heat or increased pressure is applied the petroleum wax is forced to migrate into the porous substrate and the acrylic copolymer contacts the surface causing a build in adhesion to the point of nonremovability this is especially effective when the substrate is fibrous e g paper the wax then flows into the fibers of the paper allowing more of the acrylic copolymer to contact the paper building adhesion continued contact with the substrate over a period of time will also result in flow of the petroleum wax into the porous substrate called 34 cold flow 34 such flow slowly results in increased contact of the acrylic copolymer with the substrate causing adhesion build while the period of time required for permanent adhesion to result from.