Linerless record material
View Patent ↗The invention describes a composition and method of providing an improved recording material, such as an ink receptive recording material or thermally responsive record material useful for linerless labels. The record material comprises a support having provided thereon on one surface an adhesive material, and on at least one other surface, an ink receptive coating or a heat sensitive imaging coating. The method comprises applying to a first surface a first layer of a coating of an ink receptive material or of a heat sensitive color-forming composition comprising a binder material and a substantially colorless dye precursor and an acidic developer material in substantially contiguous relationship. The adhesive is heat activated. The record material exhibits substantially no tack at 23° C., 40% relative humidity when pressure is applied, however develops high peel strength (300 grams/inch) upon application of 7 mJ/mm 2 to 13 mJ/mm 2 of heat energy.
1. A record material useful for linerless labels, the record material comprising:
i). a support having first and second surfaces;
ii). a heat activated adhesive containing a tackifier provided on one surface of the support, the heat activated adhesive having substantially no tack at 23° C., 40% relative humidity with an applied pressure of 55.9 g/cm2 however, the heat activated adhesive having a peel strength of at least 300 grams/inch upon application of from 7 mJ/mm2 to 13 mJ/mm2 of heat energy and a tackifier softening point of 145-151° C.
2. The record material according to claim 1 wherein the first surface of the support has an ink receptive coating applied to the first surface of the support.
3. The record material according to claim 2 wherein the record material includes in addition a polymeric top coat.
4. The record material according to claim 1 wherein the record material is a thermally responsive record material and having provided on at least one surface of the support, a heat sensitive coating comprising a substantially colorless dye precursor and an acidic develop material, and including in addition a binder material.
5. The thermally responsive record material according to claim 4 wherein the heat activated adhesive is applied at a coat weight of from 0.1 to 8 gsm.
6. The thermally responsive record material according to claim 4 wherein the heat activated adhesive comprises an acrylate adhesive and the tackifier.
7. The thermally responsive record material according to claim 4 wherein the heat activated adhesive prior to activation has a coefficient of static friction of 0.60 or less per Tappi T549.
8. The thermally responsive record material according to claim 4 wherein the heat activated adhesive is applied to only a portion of the second surface.
9. The record material according to claim 4 wherein the record material includes in addition a polymeric top coat.
10. The thermally responsive record material according to claim 9 wherein the top coat is receptive to inks.
11. The thermally responsive record material according to claim 4 wherein the substantially colorless dye precursor comprises a fluoran compound.
12. The thermally responsive record material according to claim 4 wherein the heat sensitive composition is applied onto the support at from 0.5 to 8 gsm.
13. The record material according to claim 4 including an additional layer on a surface of the support, comprising a reflective layer, insulating layer, hollow sphere layer, or isolation layer positioned between the surface and either of the heat sensitive coating or heat activated adhesive.
14. The record material according to claim 1 wherein the support is paper or film.
15. The record material according to claim 1 wherein the support is a paper with a basis weight of 150 grams per sq. meter or less, or film.
16. The record material according to claim 1 wherein the adhesive is selected from alkyl acrylate, multifunctional acrylate, polyurethane, or an activatable adhesive comprising a chain transfer agent.