10. Why does the mold glue dry on the surface but not in the inside?

Mold silica gel belongs to condensation silica gel, which is solidified by absorbing water in the air. This phenomenon occurs when the water is evaporated dry without adding an appropriate amount of water in the process of making silica gel. Solution: this phenomenon is not a product quality problem, but because the water content is not controlled and the storage life of silica gel is improved, some phenomena will appear for a long shelf life. As long as 0.05% water is added appropriately and stirred evenly when silica gel is used, some problems can be solved.

11. How to solve the problem of non curing of mold silica gel?

When making silica gel mold, due to some reasons, the mold silica gel has not been cured for 24 hours. Today, we will analyze how to avoid non curing by controlling the ratio of silica gel to curing agent.

The curing of mold silica gel will be affected by temperature. On the contrary, the curing speed will be faster when the temperature is high. On the contrary, the curing speed will be slower when the temperature is low. When making silica gel mold, it is necessary to appropriately modify the ratio of silica gel and curing agent to ensure the normal curing of silica gel.

The greater the amount of curing agent added, the faster the reaction speed of silica gel, and the ratio of curing agent to silica gel shall not be less than 1%. If the amount of curing agent is too small, it will not cure for a long time. The addition of curing agent not more than 5% generally has little effect on the hardness, tensile force and tear strength of silica gel.

① The dosage of curing agent is 1%, the colloid is still flowing in 2.5 hours, and demoulding can be carried out in 6-8 hours.

② The amount of curing agent is 2%, the glue will flow in 50 minutes to 1 hour, and the mold can be demoulded in 2-3 hours.

③ The dosage of curing agent is 3%, the colloid is still flowing for 28-30 minutes, and the mold can be demoulded in 1.5-2 hours.

④ The dosage of curing agent is 4%, the colloid is still flowing for 10-15 minutes, and the mold can be demoulded in 1-1.5 hours.

After the silica gel curing agent is added to the mold silica gel, it must be stirred evenly. If it is not stirred evenly, part of the fixed line will not be fixed. If the fixed line cannot be fixed after 48 hours, the mold will be scrapped and will not be cured. It can only be cleaned and the mold can be made again.

12. Why does the die glue have poor tension?

In order to reduce the viscosity of silica gel and make silica gel easy to operate, customers add a large amount of silicone oil to silica gel in the process of making molds, which will make silica gel very soft, resulting in non tensile resistance, reduced tear strength and poor tensile force, resulting in non durable molds, short service life and less turnover times.

13. Why does the mold leak oil?

The mold silica gel itself will not emit oil. The oil emission is due to the addition of composite silicone oil (the compound of silicone oil and white mineral oil) in the operation process, because white mineral oil is a petrochemical product, not silicone oil.

14. Why is the mold not resistant to acid and alkali and aging?

In the process of making silica gel mold, we suggest that customers should not add any silicone oil. If necessary, the amount of silicone oil should not exceed 5% ~ 10%. Because excessive addition of silicone oil will destroy the molecular weight of silica gel, the mold will not be acid-base resistant and aging resistant.

15. Why does the mold made of silica gel have traces, stripes and unsmooth on the surface?

This phenomenon occurs because the product or model to be copied is not polished or polished. In fact, the model or product itself is not smooth or perfect, so if the product or model to be copied has not been polished or polished, the mold made of good silica gel will be unsightly and not smooth enough. There is also a case that the mold is not smooth if it is not painted evenly when the release agent is applied.