In the past:
In China, decorative base paper has only a production history of more than 40 years and is still a new industry.
Nowadays:
As people’s requirements for decoration styles become increasingly diverse, it is necessary to continuously improve the performance of decorative base paper to meet the requirements of later processing. Decorative base paper has strict requirements on optical properties such as whiteness, and titanium dioxide is expensive, so it is very important to find a filler with similar performance to titanium dioxide to replace titanium dioxide.
Research:
- Scientists explored the papermaking process of decorative base paper, which showed that 1.the ratio of softwood pulp to hardwood pulp was 6:4; 2.the beating degree was 33°SR;3. the amount of PAE added was 2%;4. the amount of titanium dioxide added was 30%; 5.and the amount of CPAM added was 0.06%.
- Under these conditions, the requirements of decorative base paper for strength, air permeability, absorbency and optical properties can be met. When preparing titanium dioxide/kaolin composite fillers, four influencing factors were selected: the amount of dispersant, the ratio of titanium dioxide to kaolin, the reaction time and the grinding concentration. After orthogonal experimental analysis, the process conditions for the prepared composite were 0.3% dispersant, 5:5 ratio of kaolin/titanium dioxide, 0.5h compounding time and 45% grinding concentration. In that cases, the whiteness of the prepared titanium dioxide/kaolin composite filler was 92.5%ISO and the hiding power was 30.33g/m2. The composite effect of titanium dioxide/kaolin composite filler was characterized by scanning electron microscopy (SEM), infrared spectroscopy (FTIR) and X-ray diffraction (XRD). Scanning electron microscopy (SEM) can visually observe the composite of titanium dioxide and kaolin. Through Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis, it was found that the coating of titanium dioxide with kaolin was not a simple physical adsorption, but a chemical reaction. Chemical bonds Si-O-Ti and Al-O-Ti were formed between titanium dioxide and kaolin, the crystal structure changed, and the coating effect was good.
Comparison:
In addition, the effects of pressing + vacuum drying, vacuum drying, pressing + flat plate drying, and flat plate drying on the performance of decorative base paper when adding composite fillers and mixed fillers were compared.
- The first three drying methods are more beneficial to maintaining the strength of the base paper,
- but the air permeability and absorbency of the base paper obtained by pressing + vacuum drying are slightly poor,
- And the use effects of vacuum drying and pressing + flat plate drying are not much different;
- when flat plate drying is used, the strength of the base paper is poor, the air permeability and absorbency are good, and it cannot meet the needs of production;
The four drying methods have little effect on the optical properties of the base paper and cannot be used as a standard to distinguish the optical properties of the base paper.
suggestion：
Therefore, the effects of vacuum drying and pressing + flat plate drying are both suitable. After adding four different fillers, kaolin, titanium dioxide, titanium dioxide/kaolin composite filler, and kaolin and titanium dioxide mixed filler, to paper, the difference in whiteness and opacity of the paper sheets is very small. In terms of strength performance, air permeability and capillary absorption height, the composite filler has a better effect, and its performance is close to that of titanium dioxide.