Process for producing 3D structures from rubber material

1. A process for producing a three dimensional structure, the process including the following steps

a) applying of at least a first material M 1 onto a substrate to build a first layer L 1 on the substrate;

b) layering of at least one further layer L y of the first material M 1 or of a further material M x onto the first layer L 1 , wherein the at least one further layer L y covers the first layer L 1 and/or previous layer L y-1 at least partially to build a precursor of the three dimensional structure;

c) curing the precursor to achieve the three dimensional structure;

wherein at least one of the materials M 1 or M x is applied at a Mooney viscosity of >10 ME at 60° C. and of <200 ME at 100° C.

2. The process according to claim 1 , wherein the process provides at least one of the following features:

(1) the curing step c) is started independently for each layer L 1 to L y before, during or after one of the steps a) or b);

(2) at least one of the materials M 1 to M x has a Tg below 25° C. before and/or after curing step c);

(3) at least one of the materials M 1 to M x has a molecular weight of 5 to 5000 kg/mol;

(4) at least one of the materials M 1 or M x or the three dimensional structure has an elongation at break of >30% after curing step c);

(5) at least one of the materials M 1 or M x experiences no phase transition above 50° C. before and/or after curing step c).

3. The process according to claim 2 , wherein step a) or step b) is established by utilizing an application tool, wherein the application tool provides at least one of the following features:

I) at least one opening for applying the first material in the range of from 0.01 to 1000 mm2;

II) two to 100 openings;

III) an application rate of >10 g/hour;

IV) a temperature in a range of from 50° C. to 400° C.,

V) a temperature difference of the application tool opening compared to the temperature of the first material M 1 or the further material M x when leaving the opening of the application tool in a range of from 0° C. to ±50° C.,

VI) a material temperature directly after the opening in a range of from 50° C. to 250° C.,

VII) a symmetrical or asymmetrical shaped opening with the largest diameter being <1000 mm;

VIII) an opening with a potentially variable diameter wherein the largest diameter of the opening can change by up to ±500%.

4. The process according to claim 3 , wherein the application tool or the substrate is arranged to be movable in at least one of the spatial directions X, Y or Z.

5. The process according to claim 1 , wherein the hardness of the cured material M 1c or M xc has increased by at least 5 Shore A points compared to the applied material M 1 in step a) or M x in step b) before curing.

6. The process according to claim 1 , wherein the applying of the materials including at least one material M 1 or M x in step a) or step b) is executed according to digital data related to the shape of the three dimensional structure which are established and provided by a computer aided process.

7. The process according to claim 1 , wherein the first material M 1 or at least one of the further materials M x is compounded before step c) comprising 100 parts of an ultra-high viscosity polymer, 0 to 300 parts of an organic or inorganic filler, 0 to 150 parts of a plasticizer, 0 to 40 parts of a metal oxide, 0 to 20 parts of an anti-degradant, 0 to 10 parts of process aids, 0 to 20 parts of coagent and 0.1 to 20 parts of a curative.

8. The process according to claim 1 , wherein the three dimensional structure is cured in step c) at a temperature ≥the temperature of the material leaving the application tool.