Hello:

I thought that following polymerization, photocurable resins needed a specific molecular weight of oligomers to give them strength and tiny molecules (monomers) to provide them fluidity. The oligomer absent from your formulation. Additionally, the TPO concentration can range from 0.5 to 3% wt, and you should be mindful that the UV light's wavelength must match the type of TPO.

Dear Dr Li,

Thanks for your kind response,

I added the oligomer as per your advice, and it got better, but I also have a problem with oxygen inhibition. I can not cover the surface with some substrate. I need to solve that chemically. Do you have any offers for me to overcome this problem?

Best regards,

Even with pure oxygen, the inhibition's effect is not immediately apparent; it can only be 5–50 μm, and qualified slurry does not need to take this into account.The presence of oil on the surface, which may be monomers that are not involved in the reaction, can be controlled the resin ratio to reduce it (or the UV power is too large? We commonly test with 5-50mW/cm²). Maybe there are some impurities or monocase with ungrafted acrylate functional groups. You can find out by FTIR testing the oil.

Dear Dr Li,

Thanks for your precise response,

I use this resin for very thin films with a height of around 20 μm. Regarding that, the oxygen inhibition effect is shown to be significant. I used some chemicals to overcome this issue but could only increase the DC to 70%. Therefore, I still have the hazy and oily surface.

Best regards,

Acrylate-based light curing does have this problem, but another type of click reaction has been tried ? It can avoid the problem of oxygen inhibition. Examples include vinyl and sulfhydryl.

And，I am not a Dr, I am a master who has started to work in the enterprise, thanks for your recognition~