| Author | Ngo Tien Luan |
| Call Number | AIT Thesis no.PP-06-17 |
| Subject(s) | Paper coatings
|
| Note | A thesis submitted in paitial fulfillment of the requirements for the degree of Master of Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | The objective of this study was to find out the effects of pigment patiicle size and CMC dosage on the properties of coating color and coating layer of coated paper. Coating now becomes more important section in paper industry due to its benefits to coated paper properties. Coating color is a mixture of minerals, colloidal particles and dissolved polymers which are applied onto the base paper surfaces. Coating color must have optimum flow properties in spite of high solids content to obtain good printability and a uniform coating layer. There are some components in coating color but pigments are the most important factors affecting coating color and coated paper properties. Kaolin and GCC (ground calcium carbonate) are common pigments used in coating. They are the most used pigments because of high value and high quality, easy to manufacture. CMC is used as a co-binder and thickener in coating color to Improve coating color propeIiies and coated paper properties. The results show that, finer particle size influences high viscosity and water retention of coating color. Viscosity as well as water retention increases with finer particle size. Particle size also effects strongly on coated paper and plastic film, finer particle size of kaolin and GCC influences higher optical properties and mechanical propeIiies, decreases surface properties. Higher brightness, opacity, whiteness and gloss can be achieved by finer particle size. PPS rouglmess, Bendtsen roughness and air permeance decreases when finer particle size proportion of pigment increases. Tensile strength, modulus and dry pick resistance seem to increase when finer patiicle size proportion increases. The results also show that, when mixing ratio of kaolin clay and GCC influence low viscosity and water retention. Mixing ratio of GCC influences higher brightness, whiteness and lower opacity and gloss. Mixing ratio also decreases surface properties and tear strength but increases with tensile strength and modulus. The results also show that when CMC dosage increases in coating color, higher viscosity and water retention can be achieved. CMC dosage seems to increase tensile strength, modulus and dry pick resistance. CMC does not influence optical properties such as: brightness, whiteness, opacity and gloss. It is the same with surface properties; CMC doesn't effect on them. During the study it was found that changing proportion of finer particle size, mixing ratio of pigment and CMC dosage resulted in properties of coated paper. The differences of finer pigment particle size, mixing ratio and CMC dosage influence coating color, optical, surface and mechanical properties. Controlling these properties enables to produce coated papers of higher quality |
| Year | 2006 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Pulp and Paper Technology (PP) |
| Chairperson(s) | Lehtinen, Esa |
| Examination Committee(s) | Malinen, Raimo O.;Nazhad, Mousa M. |
| Scholarship Donor(s) | Government of Finland-AIT Fellowship |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2006 |