초록 ▼

A paper having an improved print quality comprises a paper substrate having a surface with a surface roughness of less than 6 microns and a surface gloss of 5-80% which surface has been coated with a light-weight, low solids content, top coat. The top coat may comprise (i) a rheology modifier/binder

A paper having an improved print quality comprises a paper substrate having a surface with a surface roughness of less than 6 microns and a surface gloss of 5-80% which surface has been coated with a light-weight, low solids content, top coat. The top coat may comprise (i) a rheology modifier/binder component and at least one pigment or (ii) at least one binder coated pigment. The top coat provides a significant improvement to the delta gloss of the so-treated paper.

대표청구항 ▼

1. A paper having an improved print quality, comprising:(i) a paper substrate, said paper substrate having a front and a back, and a surface on at least one of said front and said back of said paper substrate, said surface having a surface roughness of less than 6 microns and a surface gloss of 5-80

1. A paper having an improved print quality, comprising:(i) a paper substrate, said paper substrate having a front and a back, and a surface on at least one of said front and said back of said paper substrate, said surface having a surface roughness of less than 6 microns and a surface gloss of 5-80%; and (ii) a top coat disposed on said surface, said top coat comprising at least one binder coated pigment, said binder being present in an amount of 1-50 wt % based on the weight of said at least one pigment, said at least one pigment having an average particle diameter of 200 to 2000 nm, said top coat being a partial mono-layer of particles of said at least one pigment or clusters of said particles of said at least one pigment. 2. The paper having an improved print quality as claimed in claim 1, wherein said at least one pigment is a mineral pigment.3. The paper having an improved print quality as claimed in claim 1, wherein said at least one pigment is a synthetic plastic pigment.4. The paper having an improved print quality as claimed in claim 1, wherein said at least one pigment comprises synthetic plastic pigment particles comprising at least one polymer core phase containing at least one void, at least one polymer shell phase at least partially surrounding said core, and at least one channel connecting said void in said core to the exterior of said particle.5. The paper having an improved print quality as claimed in claim 1, wherein said top coat further comprises an optical brightening agent in an amount of 0.1 to 20 parts by weight for each 100 parts by weight of said at least one pigment.6. The paper having an improved print quality as claimed in claim 1, wherein said top coat has been calendered to increase its sheet gloss to a value not greater than 50%.7. The paper having an improved print quality as claimed in claim 1, wherein said surface is formed by at least one coating disposed on at least one of said front and said back of said paper substrate.8. A process of making a paper having an improved print quality, comprising:(i) providing a paper substrate, said paper substrate having a front and a back, and a surface on at least one of said front and said back of said paper substrate, said surface having a surface roughness of less than 6 microns and a surface gloss of 5-80%; and (ii) applying an aqueous top coat over said surface, said aqueous top coat having a solids content of 1 to 40% by weight, said aqueous top coat composition comprising water and at least one binder coated pigment, said binder being present in an amount of 1-50 wt % based on the weight of said at least one pigment, said at least one pigment having an average particle diameter of 200 to 2000 nm, said top coat being a partial mono-layer of particles of said at least one pigment or clusters of said particles of said at least one pigment; and (iii) drying said aqueous top coat. 9. The process as claimed in claim 8, wherein said aqueous top coat composition has a solids content of 10 to 40% by weight.10. The process as claimed in claim 8, wherein said aqueous top coat composition has a solids content of 25 to 35% by weight.11. The process as claimed in claim 8, further comprising calendering said dried cop coat to produce a surface gloss of not more than 50%.12. The process as claimed in claim 8, wherein said dried top coat is calendered to produce a surface gloss of not more than 30%.13. The process as claimed in claim 8, wherein said aqueous top coat further comprises an optical brightening agent in an amount of 0.1 to 20 parts by weight for each 100 parts by weight of pigment.