Roll-to-roll slot die coating method to create interleaving multi-layered films with chemical slurry coatings
An improved method for manufacturing a continuous self-healing barrier film is provided. The method includes slot-die coating opposing sides of a separator substrate with a curing agent slurry and a curable resin slurry using a single-sided coating line or a tandem coating line. The method also includes sequentially interleaving inner and outer protective layers via a continuous roll-to-roll process to create a multi-layered barrier film. The barrier film can optionally be formed into a barrier envelope, and an insulating core material can be inserted into the barrier envelope to define an enclosure. Evacuating and sealing the enclosure along a perimeter of the barrier envelop forms a self-healing vacuum insulation panel with excellent properties for use as a building material and in refrigeration systems, for example. The barrier film can alternatively be used in the manufacture of tires, roofing, cargo containers, food packaging, and pharmaceutical packaging, for example.
1. A method for manufacturing a multi-layer barrier film, the method comprising:
unwinding a separator substrate as a continues web, the separator substrate comprising a polymer and having a first surface opposite a second surface;
slot-die coating the first surface of the separator substrate with a first slurry to form a first layer thereon;
applying a first interleaving web from a first supply roll onto the first surface of the separator substrate to sandwich the first layer therebetween, the first interleaving web comprising a first polymer film liner;
slot-die coating the second surface of the separator substrate with a second slurry to form a second layer thereon;
applying a second interleaving web from a second supply roll onto the second surface of the separator substrate to sandwich the second layer therebetween, the second interleaving web comprising a second polymer film liner;
wherein one of the first slurry and the second slurry includes a curable resin slurry and the other of the first slurry and the second slurry includes a curing agent slurry, and wherein one of the first layer and the second layer includes a curable resin layer and the other of the first layer and the second layer includes a curing agent layer, the curing agent layer being capable of reacting with the curable resin layer to seal a perforation of the separator substrate; and
rewinding the separator substrate together with the first interleaving web and the second interleaving web into a wound roll, wherein at least one wrap of the wound roll include the first interleaving web, the first layer, the separator substrate, the second layer, and the second interleaving web as a multi-layer barrier film,
wherein the separator substrate includes non-metalized polyethylene terephthalate (PET), polyethylene (PE), or polypropylene (PP).
2. The method of claim 1 wherein slot-die coating the first slurry and slot-die coating the second slurry are performed in separate processing runs.
3. The method of claim 1 wherein slot-die coating the first slurry and slot-die coating the second slurry are performed inline as a single processing run.
4. The method of claim 1 wherein the curing agent slurry includes an imine-functional group or a thiol-functional group and wherein the curable resin slurry includes an epoxide-functional group.
5. The method of claim 1 wherein the curing agent slurry includes an imine-functional group or a thiol-functional group and wherein the curable resin slurry includes an acrylate-functional group.
6. The method of claim 1 wherein the curing agent layer and the curable resin layer each define a thickness of between 5 μm and 200 μm, inclusive.
7. The method of claim 1 further including evaporating a solvent from the first slurry to form the first layer and evaporating a solvent form the second slurry to form the second layer.
8. The method of claim 1 further including providing a first slot-die head and a first backing reel for slot-die coating the first surface of the separator substrate.
9. The method of claim 1 further including providing a second slot-die head and a second backing reel for slot-die coating the second surface of the separator substrate.