Flexible seaweed-based thin films and associated solution casting systems and methods

A seaweed-based thin film, comprising:

• a seaweed-based composition comprising agar, alginate, carrageenan, semi-refined seaweed, and/or unprocessed seaweed;
• an agent comprising glycerin, sorbitol, sodium lignosulphonate, potassium lignosulphonate, calcium lignosulphonate, ammonium lignosulphonate, lignosulphonate, ascorbic acid, citric acid, ethylene glycol, polyethylene glycol, polyglyceride fatty acid esters, guar gum, tributyl citrate, erucamide, calcium carbonate, propylene glycol, natural colorants, and/or odor absorbers;
• and
• water,
• wherein:
• the seaweed-based composition comprises 50-90 wt % of the seaweed-based thin film,
• the agent comprises no more than 40 wt % of the seaweed-based thin film,
• the water comprises 0.1-50 wt % of the seaweed-based thin film, and
• when in a salt concentration of less than 900 microSiemens, the thin film composition exhibits a degree of swelling of no more than 300%.

A coated substrate, comprising:

• a substrate comprising paper, polyvinyl alcohol, polyester, and/or polyolefin;
• and
• a coating applied to the substrate, the coating comprising:
• a seaweed-based composition comprising agar, alginate, carrageenan, semi-refined seaweed, and/or unprocessed seaweed;
• an agent comprising glycerin, sorbitol, sodium lignosulphonate, potassium lignosulphonate, calcium lignosulphonate, ammonium lignosulphonate, lignosulphonate, ascorbic acid, polyglyceride fatty acid esters, guar gum, tributyl citrate, erucamide, calcium carbonate, natural colorants, and/or odor absorbers;
• and
• water,
• wherein the coating comprises 5-99 wt % of the coated substrate, and
• wherein, when in a salt concentration of more than 900 microSiemens, the thin film composition exhibits a degree of swelling of no more than 200%.

A coated substrate, comprising:

• a substrate comprising paper, polyvinyl alcohol, polyester, and/or polyolefin;
• and
• a coating applied to the substrate, the coating comprising:
• a seaweed-based composition comprising agar, alginate, carrageenan, semi-refined seaweed, and/or unprocessed seaweed;
• an agent comprising glycerin, sorbitol, sodium lignosulphonate, potassium lignosulphonate, calcium lignosulphonate, ammonium lignosulphonate, lignosulphonate, ascorbic acid, citric acid, ethylene glycol, polyvinyl alcohol, polyethylene glycol, polyglyceride fatty acid esters, guar gum, tributyl citrate, erucamide, calcium carbonate, propylene glycol, natural colorants, and/or odor absorbers;
• and
• water,
• wherein the coating comprises 5-99 wt % of the coated substrate, and
• wherein the substrate comprises a heat-sealable layer.