Dual cure cyanate ester inkjet composition

A process for printing a three-dimensional object comprising the steps of:

• (a) jetting an inkjet composition by means of a printing machine to form a layer in a configured pattern corresponding to the shape of the object, the inkjet composition comprising:
• i) photo polymerization reactive compound (M) containing exactly one acryloyl group,
• ii) photo polymerization reactive compound (N) containing at least two acryloyl groups,
• iii) radical photoinitiator (R),
• iv) cyanate ester compound (D) containing at least two cyanate groups, and
• v) cyanate ester curing catalyst (C), wherein
• (M) is different from (D) with the proviso that cyanate ester compound containing exactly one acryloyl group and additionally containing at least two cyanate groups is subsumed to (D),
• (N) is different from (D) with the proviso that cyanate ester compound containing at least two acryloyl groups and additionally containing at least two cyanate groups is subsumed to (D),
• 25-50 mol % of the contained acryloyl groups are provided by the reactive compound (N) and the molar ratio of contained acryloyl groups to contained cyanate groups of compound (D) is 0.30 to 0.95, and
• the inkjet composition has 1.0-5.0 mol/kg acryloyl groups
• (b) irradiating the formed layer to form a photo-cured layer,
• (c) sequentially repeating steps (a) and (b) to form a plurality of photo-cured layers in order to prepare a green body of the three-dimensional object, and
• (d) heating the green body to post cure the three-dimensional object.

A three-dimensional object manufactured from an inkjet composition comprising:

• i) photo polymerization reactive compound (M) containing exactly one acryloyl group,
• ii) photo polymerization reactive compound (N) containing at least two acryloyl groups,
• iii) radical photoinitiator (R),
• iv) cyanate ester compound (D) containing at least two cyanate groups, and
• v) cyanate ester curing catalyst (C), wherein
• (M) is different from (D) with the proviso that cyanate ester compound containing exactly one acryloyl group and additionally containing at least two cyanate groups is subsumed to (D),
• (N) is different from (D) with the proviso that cyanate ester compound containing at least two acryloyl groups and additionally containing at least two cyanate groups is subsumed to (D),
• 25-50 mol % of the contained acryloyl groups are provided by the reactive compound (N) and the molar ratio of contained acryloyl groups to contained cyanate groups of compound (D) is 0.30 to 0.9, and
• the inkjet composition has 1.0-5.0 mol/kg acryloyl groups.