The paper industry has been using kaolin in its manufacturing process. These days, there seems to be a renewed interest in its use within the industry of papermaking. What are the uses of kaolin in paper industry in the contemporary era? How does it benefit the paper industry? What is the direction going forward?
The Advantages of Kaolin Use in Papermaking
Kaolin is a type of clay with distinctive characteristics. The particles of kaolin are very fine, so it feels smooth when touched. The color is also pure, which makes it infamous as a color pigment. Additionally, in fine powder form, kaolin is easily dispersed in water.
The mineral is less abrasive compared to other materials commonly used in papermaking. These characteristics are important in paper manufacturing. Paper industry is not the only industry that benefits from kaolin. Construction and agriculture are among the industries that take advantage of them.
Here are the benefits of kaolin in paper industry:
1. Improving the Look
As stated, kaolin is a pure color pigment. Whether the color naturally occurs or due to some production process, the pigment is really strong. To create papers as we constantly use these days, kaolin is used to provide a coating on its surface. This coating makes the paper look bright, glossy, and smooth to the touch.
2. Increasing the Ease of Printing
Kaolin coating works more than making the paper look good. It also increases the ease of printing on that paper. You might not realize it, but the quality of a print work also depends on the surface of the paper. The clay coating can perform this task because:
- It improves the adherence of ink onto the paper’s surface.
- It makes the ink pigment stand out even better.
- It reduces the tendency of lint formation on the paper’s surface.
- It increases the roughness where the printing machine makes direct contact.
3. Reducing Cost and Pulp Resource
Paper production requires filler material. The addition of filler in the manufacturing process is called loading. Filler is necessary to achieve the desired look and functionality of the paper, as mentioned above. In the overall production scheme, filler use is very important.
Filler is used to reduce the cost of production. It is because the filler percentage can tamper with the pulp percentage. Higher filler volume means lower pulp requirement. Thus, the production does not demand as many tree resources to produce the pulp. However, balance must be obtained as paper with not enough pulp would be brittle and less durable.
4. Maintaining the Production Machine
Because of the fineness of its particles, kaolin is not abrasive. It means that the production machine does not need to work hard to churn the material. Thus, the machine’s life can be prolonged. In manufacturing, it is important to maintain the machine’s stability and durability for consistent production.
5. Non-Toxic Waste
Any industry these days struggles to find a way to limit damage to the environment. Thus, everyone is scratching their head, looking for materials that cause minimal to no harm to the environment. Kaolin is a great material because it is generally non-toxic. The waste will not be detrimental to the surrounding environment with proper management.
Modern Uses of Kaolin in Paper Industry
Paper manufacturing has seen continuous changes over the years. More findings are obtained. These findings are not only for the sake of improving the production quality. They also provide some answers to the challenges of this industry: low natural resources and environment-related issues.
Kaolin use in paper manufacturing also sees developments in recent years. It is a favorite filler material, but using too much of it will significantly reduce the paper’s quality. Thus, there are efforts to modify the kaolin compound structure to manifest the desired quality with fewer resources needed.
Certain modifications in the compound will produce specific results. Here are some findings of engineered kaolin used in paper manufacturing:
- A mix of calcined kaolin and hydrous kaolin for higher opacity and brightness
- Certain kaolin coating with specific particle size for efficient dispersing
- Kaolin with more open particles to produce paper with better light scattering
- Defined and delaminated kaolin clay filler improves the printability of the paper
The utilization of kaolin in paper industry is definitely not new. This mineral provides numerous benefits to the essential industry. In the modern era, engineered clay products are created to solve the challenges proposed by the paper industry.