Generally, Visco-elastic material is very sensitive to temperature and body heat. It quickly reacts and conforms according to your body shape. It is ranked by its reliability and few other factors. Here are those significant materials that ensure you have a good quality mattress.
1. Weight
Have you ever thought how memory foam is graded and how can we calculate its weight. Basically, there are many chemicals used and combined through a complex process to manufacture polyurethane foam. Additional chemicals ensure higher quality and extra visco-elastic and density. However, you can not measure its density by resilience of a foam mattress. There is difference in weight and density of foam, many manufacturers 2-3lbs density and others prefer 4-5lbs.
2. Indentation Load Deflection (ILD Rating)
ILD rating plays a significant role in foam grading. You can measure foam's softness and hardness through ILD Rating. A 4 inch dense memory foam mattress must have a 25% compression or 25% ILD Rating. For Example 25lbs ILD determine that this substance took 25lbs to move up 25%. Remember, that higher ILD confirm better foam quality.
3. Flexibility
Flexibility is measured by the mattress's resilience. It is calculated dropping a ball from 36 feet height. The more memory mattress rebound after the steel ball hit it the more durable and flexible it is. Though, visco-elastic memory foam may appear less resilient.
4. Tensile
Tensile is measured by the degree this mattress can be stretched. This is determined in pound/square inch. Tensile is essential in Memory Foam Mattress grading as these mattresses are usually not stretchable but comfortable for a sound sleep.