Smart Tea Bag / Tea Bag

When we make tea with the common tea bag in our daily life, we always can’t control the time how long the tea bag should stay in the hot water. We also notice that the cotton thread tied with the tea bag and the paper label will absorb the water and at last the paper will be humidified.
Our designation is to make a new paper label using a special material and draw an outline of pattern on it.When the paper has been humidified,the pattern will change its color.The thread also should be selected to make sure that when the water arrive the label,the tea is nearly well made.