The so-called stone papermaking is to grind calcium carbonate, the main component of the stone, into ultra-fine particles, and then blow the paper with polyethylene and glue. In the context of global calls for energy conservation and emission reduction, this non-new stone paper has been labeled with the "fashion" label of low-carbon emission reduction and environmental protection, and has entered the public's vision.
However, as a paper-making product, stone paper has its unique functionality, but its technology needs to be improved, and there are still problems in recycling. Therefore, we should look at stone paper dialectically.
Stone paper is just a product of the paper industry and has been around for more than 40 years. It is nothing new. Stone paper uses calcium carbonate, the main ingredient of stone, as the main raw material, so people call it stone paper.
Stone paper is a synthetic paper in the paper industry and a plastic film in the plastics industry. As early as the 1970s, the Chinese paper industry had been conducting research and development on synthetic paper. Because synthetic paper has a plastic component, it is not easy to tear, so synthetic paper is commonly known as "tear-proof."
In the 1960s, synthetic paper, the predecessor of stone paper, appeared in Japan. Over the years, the annual output of synthetic paper in western countries has increased at a rate of 10%. In the early stage of China, stone paper was mainly imported from abroad. In the later period, a few companies also started to develop synthetic paper. Stone energy is one of them.
What is the difference between the early synthetic paper and the current stone paper?
The early synthetic paper had a calcium carbonate content of less than 60%, and it was necessary to use a large number of other added elements to synthesize. Now the content of calcium carbonate can reach 80%, and the high-quality calcium carbonate is not expensive per ton, which reduces the cost.
At present, synthetic paper is widely used in the packaging industry, but it is rarely used for publication printing. Because synthetic paper is more expensive than paper for newspapers and periodicals, it is rarely used in publications. However, because synthetic paper is waterproof and moisture-proof, customers use it to print maps and make notebooks.
Problems still need to be resolved
In the production process, no wood is consumed, no "three wastes" are emitted, no drop of water is used, and the cost is low because the raw material is limestone. Stone paper was described by the media as a low-carbon environmental protection star product. Despite this, experts still questioned stone paper.
1. Adaptability problem
Stone paper currently on the market is thicker and heavier than ordinary paper. Stone paper of A4 size weighs 1.3 grams, while plain paper of the same specification weighs 0.7 grams. In addition, stone paper has better ink absorption than plastic, but much worse than vegetable fiber paper.
2. Raw material problems
Stone paper uses plastic components such as polyethylene. Plastic is derived from petroleum, but China's petroleum is currently relatively scarce. Some companies claim that the output of stone paper will reach more than 5 million tons in the future, which will inevitably consume a lot of oil, so there may be a shortage of raw materials. "
3. Recycling issues
"Stone paper will embrittle and crack for a long time, but the plastic macromolecules in it cannot be degraded without using special equipment." If the stone paper and fiber paper are recycled together, the stone paper will become fused and sticky once it is melted On the inside wall of the equipment, it can cause harm to the equipment.
Dialectical view of stone paper
1. Stone paper is waterproof and moisture-proof and has its functionality, but stone paper cannot replace traditional paper. As a product of the paper industry, stone paper has its existence rationality.
2. Stone paper book is just a new material. Stone paper and fiber paper have their own uses. Stone paper will not replace fiber paper.
3. Any product has its own advantages and disadvantages. We should use our strengths and avoid weaknesses when using it. Fiber paper produces pollution during the production process, but can be recycled after use to make paper pulp. Stone paper has no pollution during the papermaking process, but is generally incinerated or self-degraded after recycling, and the value of utilization is low.