Question

The refractive index of glassine paper is around.

(a) 1-2

(b) 2-3

(c) 3-4

(d) 4-5

I have been asked this question in an online interview.

The doubt is from Types of Paper in division Paper and Paper Based Packaging Materials of Food Packaging Technology

Answer 1

Right option is (c) 3-4

The explanation: The refractive index of glassine paper is around 1-2. Due to the intimate interfiber hydrogen bonding the refractive index of the glassine paper approaches the 1.02 value of amorphous cellulose, indicating that very few pores or other fiber/air interfaces exist for scattering light or allowing liquid penetration. The transparency can vary widely depending on the degree of hydration of the pulp and the basis weight of the paper. The addition of titanium dioxide makes the paper opaque, and it is frequently plasticized to increase its toughness.