Continuous Liquid Interface Production (CLIP) & Dead-Zone Photopolymer: CAM Slicing & Prepress Guide

Understand the fundamental physics of continuous vat photopolymerization (CLIP/cDLMS). Optimize oxygen dead-zone maintenance, elevator pull rates without cavitation, and sub-pixel continuous slice exposure vectors.

1. What is Continuous Liquid Interface Production (CLIP)?

Continuous Liquid Interface Production (CLIP) eliminates the discrete layer-by-layer peeling process of traditional stereolithography (SLA/DLP). In standard 3D printing, each layer requires detaching the cured photopolymer from the bottom vat window.

CLIP creates an oxygen-mediated "dead zone"—a persistent liquid boundary layer (20–50 µm thick) directly above an oxygen-permeable window, enabling uninterrupted continuous vertical elevation ($v_z = 150 - 600\text{ mm/hr}$).

2. Oxygen Diffusion & Dead-Zone Physics

The thickness of the dead zone ($d_z$) is governed by oxygen transport from the membrane:

Oxygen Dead-Zone Thickness:
  dz = sqrt( (D_O2 * [O2]_0) / (k_cure * [PI*]) )

3. Hydrodynamic Suction Forces & Stefan Lubrication Limit

As the cured part ascends at velocity $v_z$, liquid resin flows radially inward through the dead-zone gap:

Peak Hydrodynamic Suction Pressure:
  Delta_P = (3 * mu * vz * R^4) / (2 * dz^3)