1.1 Appearance should be smooth, without wrinkles, and the edge shall be in good condition. No cracks and pores, the composite layers must not be separated.
1.2 Bagged soaking solution: No peculiar smell, foreign odor, turbidity and discoloration.
2 Physical and chemical indicators
The physical and chemical indicators shall meet the following requirements:
1. Sensory indicators
1.1 Appearance should be smooth, without wrinkles, and the edge shall be in good condition. No cracks and pores, the composite layers must not be separated.
1.2 Bagged soaking solution: No peculiar smell, foreign odor, turbidity and discoloration.
2 Physical and chemical indicators
The physical and chemical indicators shall meet the following requirements: