Water-based binder solutions for use in additive manufacturing processes

A method of monitoring a print head of an additive manufacture process, the method comprising:

• positioning a thermal paper on a working surface;
• and
• depositing a water-based binder solution on the thermal paper, the water-based binder solution comprising:
• greater than or equal to 4 wt % to less than or equal to 20 wt % of a non-aqueous solvent, based on a total weight of the water-based binder solution, the non-aqueous solvent having a boiling point greater than or equal to 100° C. and less than or equal to 200° C.;
• and
• a thermoplastic binder, the thermoplastic binder comprising:
• a first polymer strand having a weight average molecular weight (Mw) greater than or equal to 5,000 g/mol and less than or equal to 15,000 g/mol;
• and
• at least one of a second polymer strand having a weight average molecular weight (Mw) greater than or equal to 10,000 g/mol and less than or equal to 50,000 g/mol and a third polymer strand having a weight average molecular weight (Mw) greater than or equal to 1,000 g/mol and less than or equal to 5,000 g/mol;
• wherein the first polymer strand differs from each of the second polymer strand and the third polymer strand;
• and
• wherein the second polymer strand differs from the third polymer strand.

A method of additive manufacturing comprising:

• depositing a layer of a powder on a working surface;
• selectively depositing a water-based binder solution comprising a thermoplastic binder and greater than or equal to 4 wt % to less than or equal to 20 wt % of a non-aqueous solvent, based on a total weight of the water-based binder solution, having a boiling point greater than or equal to 100° C. and less than or equal to 200° C. into the layer of powder in a pattern representative of a structure of a part, wherein:
• the thermoplastic binder comprises:
• a first polymer strand having a weight average molecular weight (Mw) greater than or equal to 5,000 g/mol to less than or equal to 15,000 g/mol;
• and
• at least one of a second polymer strand having a weight average molecular weight (Mw) greater than or equal to 10,000 g/mol to less than or equal to 50,000 g/mol and a third polymer strand having a weight average molecular weight (Mw) greater than or equal to 1,000 g/mol to less than or equal to 5,000 g/mol;
• wherein the first polymer strand differs from each of the second polymer strand and the third polymer strand;
• and
• wherein the second polymer strand differs from the third polymer strand;
• and
• coupling the first polymer strand with the at least one of the second polymer strand and the third polymer strand to form a green body part.