Abstract A laminate which is postformable to an arc of a circle having a radius at least as small as three-fourths inch without cracking or dulling of the surface is produced with a paper barrier sheet of wood fiber impregnated with a fully cured unplasticized malamine-formaldehyde resin by consolidating under heat and pressure a postformable substrate in direct contact with a paper barrier sheet consisting essentially of alpha cellulose impregnated with an unplasticized reaction product of formaldehyde and malamine in a mole ratio from 1.1:1 to 1.8:1. The reaction product has an acidity high enough to compensate for its low formaldehyde content, so as to cause it to become fully cured during the heat-and pressure-consolidation.
A method according to claim 1 wherein the paper barrier sheet consists essentially of alpha cellulose impregnated with an unplasticized reaction product of formaldehyde and melamine in a mole ratio from 1.2:1 to 1.7:1.
Claim 2
Dependent Claim
122 words
A heat- and pressure-consolidated postformable laminate comprising a paper barrier sheet of wood fiber which is impregnated with a fully cured unplasticized melamine-formaldehyde resin and is directly bonded to a postformable substrate, characterized in that the paper barrier sheet consists essentially of alpha cellulose impregnated with an unplasticized reaction product of formaldehyde and melamine in a mole ratio from 1.1:1 to 1.8:1 which has been fully cured during the heat-and pressure-consolidation of the laminate in a dry state at an acidity high enough to compensate for its low formaldehyde content and to permit complete cure, the laminate being postformable to an arc of a circle having a radius at least as small as three-fourths inch without cracking or dulling of the surface.
Claim 3
Dependent Claim
35 words
A postformable laminate according to claim 3 wherein the paper barrier sheet consists essentially of alpha cellulose impregnated with an unplasticized reaction product of formaldehyde and melamine in a mole ratio from 1.2:1 to 1.7:1.
Claim 4
Dependent Claim
46 words
A postformable laminate according to claim 3 comprising an overlay sheet of paper which is bonded to the barrier sheet and consists essentially of alpha cellulose impregnated with a fully cured unplasticized reaction product of formaldehyde and melamine in a mole ratio from 1.1:1 to 1.8:1.