Water-based, Envio-friendly Teaching Supplies:Set

Comparison for W-DF teaching pen,chalk and Tabula rasa pen

Products and Performance:
W-DF teaching pen
Main Composition: Water
Erasing Method: The words can be erased by the cleaning water.
Writing and health-concern: Water based, no dust, no toxicity, no odor, no harm to health Polluting index:0
Toxicity: Water-based, non-toxicity product tested by Guangdong provincial Center of Disease Control and Prevention test Report No. 08GA1361
Corrosivity: Non- corrosivity
Influence on eyes: Matt beige board, reflection rate<40% comply with the requirement of MOE, healthy for the eyes.
fire safety: Non-flammable,safe,convenient to transport and use.
Eco-friendly comment: Recycling use, Eco-friendly
Cost RMB/year(ave.2,000 words everyday) : 120

Products and Performance:
Chalk
Main Composition: Hydrated lime cream and powder
Erasing Method: Physically erasing method,dust occurs
Writing and health-concern: Dry written and dry erasing with dust, Eco-polluted and harmful fir health polluting index:100%
Toxicity: Gypsum products,writing and wiping generate substantial dust, about 0.5% of the dust will be inhaled into the lungs, may causing trigge asthma, tuberculosis, emphysema etc.
Corrosivity: Damage fingers, peeling, cocoon-based,wrinkle cleft
Influence on eyes: Non-reflective black board, dark color to make visual fatigue
Fire Safety: Non-flammable,safe,convenient to transport and use.
Eco-friendly comment: Disposable,source consuming,Eco-polluted
Cost RMB/year(ave.2,000 words everyday) : 60


Products and Performance:
Tabula rasa pen
Main Composition: Solvents including thanol,butanol,propanole etc.
Erasing Method: Physically erasing method,the ink residue pollutes the board
Writing and health-concern: Wet written and dry erasing without dust. Low toxic irritant odor, harmful for health polluting index:20%
Toxicity: Containing more than 90% ethanol, butanol and other toxic organic solvents, after inhalation may causing chronic poisoning, headache, malaise, keratitis,
nervous disorders, liver cirrhosis, long term
Corrosivity: Peeling, wrinkle, crack and inhalation can damage the skin platelets, causing chronic poisoning
Influence on eyes: Reflective white board , harmful for eyes
Fire Safety: Flammable, unsafe, inconvenient to transport and use.
Eco-friendly comment: Disposable,source consuming,Eco-polluted
Cost RMB/year(ave.2,000 words everyday) : 1,200