| 摘要 |
The present invention is generally directed to high opacity cigarette wrapping papers. The wrapping paper made according to the present invention contains a mixture of a white pigment and a black pigment. The white pigment, which can be, for instance, calcium carbonate, has a median particle size of from about 0.1 microns to about 0.5 microns, and particularly from about 0.2 microns to about 0.4 microns. It has been discovered that this particular particle size range, which is equal to one-half the wavelength of visible light, greatly increases the opacity, brightness and whiteness of the paper. Small amounts of a black pigment, such as carbon, are then added to further increase the opacity without significantly decreasing the whiteness or brightness of the paper relative to conventional cigarette paper. |
