Methods for negative 3D printing machine at high resolution
Methods and apparatus for the fabrication of solid three-dimensional objects from liquid polymerizable materials at high resolution. A material is coated on a film non-digitally, excess material is removed digitally, by laser, leaving an image of a layer to be printed, and the image is then engaged with existing portions of an object being fabricated and exposed to a non-digital UV curing light source. Since the only part of the process that is digital is the material removal, and this part is done by laser, the speed of printing and the robustness of the manufacturing process is improved significantly over conventional additive or 3D fabrication techniques.
1. A method, comprising:
coating a substrate with a material in a printing and coating unit to produce a coated substrate having a uniform layer of liquid polymerizable material thereon;
transporting the coated substrate to a negative printing unit and there removing portions of the liquid polymerizable material to leave an image of a layer of an article in the liquid polymerizable material remaining on the substrate;
after the portions of the liquid polymerizable material have been removed, transporting a resulting version of the coated substrate from the negative printing unit to a sample building unit;
in the sample building unit, engaging the liquid polymerizable material remaining on the substrate with a sample; and
in the sample building unit, curing the liquid polymerizable material remaining on the substrate with ultra-violet (UV) light when the liquid polymerizable material is in contact with the sample.
2. The method of claim 1 , wherein the uniform layer of the liquid polymerizable material on the substrate is created by one of:
driving a portion of the liquid polymerizable material from a syringe onto the substrate using an air or mechanical pump and translating the substrate towards and through a well-defined gap between rollers or knifes to create the uniform layer of the liquid polymerizable material with a thickness that is defined by the gap,
a screen-printing module in which a screen or stencil of film with well-defined holes is coated with the liquid polymerizable material and a blade or a squeegee is used to transfer the liquid polymerizable material to the substrate in a soft or hard engage,
a dispenser, an inkjet head, a gravure or micro-gravure system that coats the substrate with the uniform layer of the liquid polymerizable material,
a slot-die system that coats the substrate with the uniform layer of the liquid polymerizable material, and
a roller coating system that coats the substrate with the uniform layer of the liquid polymerizable material.
3. The method of claim 2 , wherein the uniform layer of the liquid polymerizable material on the substrate is created inside a closed cell with a controlled environment.
4. The method of claim 2 , wherein the printing and coating unit coats the substrate with more than one liquid polymerizable material.
5. The method of claim 1 , wherein the printing and coating unit includes a gap between rollers or knifes to create the uniform layer of the liquid polymerizable material with a thickness that is defined by the gap, the method further comprising translating the substrate bidirectionally through the gap in a controlled manner while adjusting a width of the gap.
6. The method claim 2 , wherein the liquid polymerizable material is a UV light curable material.
7. The method of claim 2 , wherein the negative printing unit is a laser-based system that contains a laser, the method further comprising jetting the liquid polymerizable material from the substrate to a material reuse system using the laser.
8. The method of claim 2 , wherein the substrate is one of: a continuous transparent film substrate, a transparent film substrate coated by a metal layer, or a transparent film substrate coated by a metal and a dielectric layer.
9. The method of claim 2 , wherein the substrate is rolled to deliver the image printed at the negative printing unit to the sample building unit.
10. The method of claim 2 , further comprising injecting support material to the sample at a support material addition unit.