STONE PAPER:A Breakthrough Innovation

1) Environmental impact of using conventional paper –

Paper is made up of wood pulp or recycled plastic fibres as raw material . The processing as well as acquisition of the raw material has bad repercussions on the environment as the use of wood raw materials is related to deforestation which causes Green House Gasses (CO2) emissions. The pulping process also causes water and air pollution as it is based on chlorine chemical and apart from this huge amount of water is also wasted in conventional paper making process.

2) Stone paper ( snippet)-

Stone paper" is also known as rock paper, paper from waste marble, mineral paper, or rich mineral paper. Stone paper is a product resembling paper. It is strong and durable; made from calcium carbonate with a binder of high density polyethylene. The stone paper has natural properties such as it is ultraviolet resistant, water resistant , more tear strength and it can be written in wet condition. The cost of equipment for manufacturing is 40% lower than conventional paper and it has low air or water pollution as it involves no acid, bleach or base chemical and it can be recycled.

3) Manufacturing process and types-

In the manufacturing process at first the calcium carbonate powder of 600 mesh is mixed with the with polyethylene resin, and formed into granule particles at high temperature of 220*C temperature then the melted granules and then it is compressed into mold of paper film which is then cooled down to temperature of about 80*C to 120*C then this paper film is inflated up to the level of the mold. Then paper film is stretched in all the direction so that it has two dimensional strength eventually it then goes through winding machine and rolls and after that the extra corners or borders is cut down and at last the the paper is coated with liquid to make it ready to be used for writing , printing , making books , magazines, booklets, brochures, maps etc.

The stone paper is divided into two types “S class” & “R class”. The S class is S-class means Sustainable rich mineral paper range; it’s the original stone paper. The R class is Recycled rich mineral stone paper range.

4) Characteristics-

Stone paper has unique characteristics such as anti-moth, anti-mildew, tear resistant, photodegradable, recyclable, soft, durable, oil resistant, water-proof, and stable in colour . It is also claimed that stone paper can be written while it is wet, and even the note book made from stone paper, it can be used as an umbrella

5) Environmental impact-

5.1) No Trees Cut Down-

The use of stone paper as another alternative to conventional paper may contribute in overcoming the problem of deforestation. The main raw material of stone paper is calcium carbonate in the form of calcite, rocks, marble, or others. The amount is about 80% of all materials used. As a binder, synthetic polymers such as HDPE or others are used. There is

Absolutely no fibre added to the sheet, which means no trees are cut down as is the case with conventional paper making.

processes

5.2) No Water Pollution and Air Pollution-

Replacing 1 ton of conventional paper with 1 ton of stone paper will save 7,480 gallons of fresh water . In stone paper production, water is only needed for circulating cooling water.

The stone paper production process has designed to prevent emitting toxic gasses. And it is

also claimed that stone paper production generates low carbon emission.

5.3) Photodegradable-

Unlike the conventional paper made from fibres which is biodegradable, the stone paper is not biodegradable ,but it is photodegradable and can be decomposed after being exposed to sunlight for a certain period of time.. Stone paper makers are required to think of a way that the rate of stone paper photo degradation can be controlled according to the requirement. For this purpose, a UV light barrier material can be added to control the rate of photo degradation of stone paper

5.4) Recyclable-

Stone paper can be easily recycled back into stone paper or become number 2 plastic . The recycling back into stone paper is categorised as an R-series (Recycled-series). It is a category of eco-solution products which uses 20-100% recycled stone paper mixed with 80-0% of virgin stone paper.

6) Development-

Due to HDPE resins not biologically degrade at all, efforts also have been made to find alternative synthetic resins other than HDPE. This was also done in order to reduce production costs. Some of the alternative resins that can be used among others were low-density polyethylene (LDPE), linear LDPE, polypropylene (PP), polyethylene

terephthalate (PET), polylactic acid resin (PLA), and waste plastic, recycled beverage bottles made of PET.

As stated earlier that stone paper is photodegradable; not biodegradable . To overcome this problem, stone paper which can be degraded biologically through the use of completely biodegradable polymer as a carrier was also been developed.

Apart from all this in order to improve the stone paper characteristics which were considered not in line with expectations. One of it was improving the ratio tensile strength and tear strength between longitudinal and transverse direction. The other effort was improving the fold ability of stone paper.

7) Conclusion-

The case states how stone paper gives an edge over conventional paper that is conventional paper is made from plant fibre but whereas stone paper is made from inorganic mineral found in earth mixed with synthetic resins as adhesives. Stone paper is environmental friendly as it does not use water and there is not deforestation as trees are not cut down.