Cationically and radiation curable composition

1. A curable composition comprising:

a Base Part comprising a resin matrix, the resin matrix comprising:

cationically curable components (A) comprising an aziridino moiety, and

radiation curable components (B) comprising a (meth)acrylate moiety,

wherein the cationically curable components (A) and radiation curable components (B) are present in a weight ratio of 10:1 to 1:1; and

a Catalyst Part comprising a curing system,

the curing system comprising:

a starter (A-S), and

a photo-initiator (B-I),

wherein the Base Part and the Catalyst Part are separate,

the curable composition void of reinforcing fillers and characterized by a Shore hardness A of 50 to 90, as determined according to DIN 53505:2000-8, 24 h after mixing the Base Part and the Catalyst Part and being exposed to light.

2. The curable composition of claim 1 , the cationically curable components (A) being characterized by at least one of the following:

molecular weight: from 150 to 20,000 g/mol; and

viscosity: from 15 to 300 Pa*s at 23° C.

3. The curable composition of claim 1 , the radiation curable components (B) being characterized by at least one of the following:

molecular weight: from 200 to 3,000 g/mol; and

viscosity: from 0.01 to 100 Pa*s at 23° C.

4. The curable composition of claim 1 , the starter (A-S)

selected from a Lewis acid, a Brønsted acid, a precursor of a Lewis acid, a precursor of a Brønsted acid, or a combination thereof.

5. The curable composition of claim 1 , the photo-initiator (B-I) being characterized by at least one of the following:

having a light absorption band in the range of 300 to 800 nm; and

molecular weight: from 50 to 1,000 g/mol.

6. The curable composition of claim 1 , the Base Part further comprising an accelerator.

7. The curable composition of claim 6 , wherein the accelerator is present in an amount from 0 to 5 wt. %.

8. The curable composition of claim 1 , further comprising at least one of the following component(s):

non-reinforcing filler(s);

surfactant(s); and

additive(s) selected from pigment(s), stabilizer(s), plasticisers, liquids, diluting agents, triacyl esters of glycerol, astringents(s), retarder(s), and mixtures thereof,

wherein the filler(s), surfactant(s), and additive(s) are each independently present in the Base Part or Catalyst Part.

9. The curable composition of claim 8 , wherein:

non-reinforcing filler(s) is present in an amount from 0 to 60 wt. %, and

additive(s) is present in an amount from 0 to 50 wt. %.

10. The curable composition of claim 1 , wherein:

cationically curable components are present in an amount from 5 to 90 wt. %,

radiation curable components are present in an amount from 1 to 30 wt. %,

starter is present in an amount from 2 to 20 wt. %, and

photo-initiator is present in an amount from 0.01 to 3 wt. %,

wt. % with respect to the weight of the whole composition.

11. The curable composition of claim 1 , being characterized by one or more of the following:

viscosity of Base Part and/or Catalyst Part: from 2 to 500 Pa*s at 23° C.;

consistency: less than 40 mm, after exposure to light and if determined according to ISO 4823:2015-08:2007-10;

and

hardening within 15 min within a temperature range from 20 to 40° C. to a rubber elastic mass after mixing the Base Part and the Catalyst Part.

12. The curable composition of claim 1 , further comprising one or more of:

filler(s),

surfactant(s), and

accelerator,

wherein:

the starter (A-S) is selected from Lewis acids, Brønsted acids, precursors of Lewis acids, precursors of Brønsted acids, or a mixture thereof, and

the photo-initiator (B-I) is selected from alpha-diketone and phosphine oxide components.

13. A cured composition obtained by mixing and subsequently radiating the Base Part and the Catalyst Part of claim 1 , the cured composition being characterized by one or more of the following features:

Shore hardness A: from 40 to 90 as determined according to DIN 53505:2000-8, 24 h after the mixing and radiating;

Tensile strength: above 4 MPa as determined according to DIN 53504:2015-08, 24 h after the mixing and radiating; and

being rubber elastic.

14. The curable composition of claim 1 , the radiation curable components (B) further comprising a urethane moiety.

15. The curable composition of claim 1 , the photo-initiator (B-I) selected from alpha-diketone component(s), phosphine oxide component(s), or a mixtures thereof.

16. A process for preparing a dental impression including sub-gingival parts, the process comprising:

combining the Base Part and the Catalyst Part of claim 1 to obtain a mixture,

radiating the mixture to obtain a radiated mixture,

applying a first portion of the radiated mixture into a tooth sulcus,

optionally radiating the radiated mixture applied to the tooth sulcus,

applying a second portion of the radiated mixture to a dental tissue surface, and

removing the first and second portions of the radiated mixture from the tooth sulcus and the dental tissue surface.

17. The process of claim 16 , wherein one or more of:

the starter

selected from Lewis acids, Brønsted acids, precursors of Lewis acids, precursors of Brønsted acids, or a mixture thereof;

the photo-initiator (B-I) selected from alpha-diketone component(s), phosphine oxide component(s), or a mixture thereof,

the photo initiator being characterized by one or more of the following features:

having a light absorption band in the range of 300 to 800 nm; and

molecular weight: from 50 to 1,000 g/mol;

the cationically curable components (A) being characterized by at least one of the following:

molecular weight: from 150 to 20,000 g/mol; and

viscosity: from 15 to 300 Pa*s at 23° C.; and

the radiation curable components (B) optionally further comprising a urethane moiety, and being characterized by at least one of the following:

molecular weight: from 200 to 3,000 g/mol; and

viscosity: from 0.01 to 100 Pa*s at 23° C.

18. A kit of parts comprising:

the curable composition of claim 1 , and

one or more of:

an application device;

a radiation source; and

a dental impression composition,

wherein the dental impression composition is different from the curable composition.

19. A process for preparing a dental impression including sub-gingival parts, the process comprising:

combining the Base Part and the Catalyst Part of claim 1 to obtain a mixture,

radiating the mixture to obtain a radiated mixture,

applying the radiated mixture into a tooth sulcus,

optionally radiating the radiated mixture applied to the tooth sulcus,

applying a dental impression material to a dental tissue surface, and

removing the radiated mixture and the dental impression material from the tooth sulcus and the dental tissue surface.