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1. (WO2007003332) IMPROVED COATING BLADE
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CLAIMS

1. A coating blade comprising:
a substrate in the form of a metallic strip; and
a wear resistant top deposit covering a working edge of the blade intended for contact with a moving paper web;
characterized by an intermediate layer between the substrate and the top deposit, said intermediate layer having a lower thermal conductivity than said top deposit.

2. The coating blade according to claim 1, wherein the thermal conductivity of the intermediate layer is below 0.5 times that of the top deposit, preferably below 0.2 times that of the top deposit.

3. The coating blade according to claim 1 or 2, wherein the intermediate layer has a thickness within the range from 10 μm to 100 μm, preferably within the range from 20 μm to 80 μm.

4. The coating blade according to claim 1 or 2, wherein the intermediate layer has a thickness of about 50% of that of the top deposit.

5. The coating blade according to any one of the preceding claims, wherein the intermediate layer comprises an inner bond coat layer, a center ceramic oxide layer, and an outer bond coat layer; wherein the center ceramic oxide layer comprises a material selected from zirconia, titania or a mixture thereof.

6. The coating blade according to claim 5, wherein the center layer comprises stabilized zirconia.

7. The coating blade according to any one of claims 1-4, wherein the intermediate layer comprises NiCr.

8. The coating blade according to claim 7, the interme-diate layer further comprising ceramic oxide particles embedded in the NiCr metal matrix.

9. The coating blade according to claim 8, wherein the embedded particles comprises titania.

10. The coating blade according to claim 7, wherein the intermediate layer is comprised of NiCr 80/20.

11. The coating blade according to any one of the pre-ceding claims, wherein the intermediate layer comprises a material selected among ceramic materials, zirconia, titania, polymer materials or any mixture thereof.

12. The coating blade according to claim 5, wherein the intermediate layer comprises titania in a mixture with chromium (Cr) .

13. The coating blade according to any one of the preceding claims, wherein the wear resistant top deposit comprises a metallic or carbide material.

14. The coating blade according to any one of the claims 1-12, wherein the wear resistant top deposit comprises a cermet.

15. The coating blade according to any one of claims 1-12, wherein the wear resistant top deposit is selected from Ni and Co alloys; WC/Co, WC/CoCr or WC/Ni materials; CrC/NiCr materials; WC and CrC in a metallic binder;
chromium plating; and chemically deposited NiP or NiB.

16. The coating blade according to any one of the preceding claims, wherein the wear resistant top deposit has a thickness within the range from 30 μm to 300 μm, preferably from 30 μm to 150 μm.

17. A process for manufacturing coating blades, comprising the steps of:
(i) depositing a first layer on a steel substrate;
(ii) depositing a second layer on top of the first layer,
characterized in that
the second layer constitutes a wear resistant top deposit comprising metallic carbide or cermet, and in that
the first layer constitutes an intermediate layer effective to reduce transfer of heat from the second layer to the substrate.

18. The process according to claim 17, wherein both the first layer and the second layer are deposited by means of an HVOF spraying process.

19. The process according to claim 18, wherein the step of depositing the first layer comprises depositing a layer containing oxide particles entrapped in a metal matrix.

20. The process according to claim 18, wherein the step of depositing the first layer comprises depositing a pure metal matrix.

21. The process according to claim 19 or 20, wherein the metal matrix is comprised of NiCr, preferably in the relation of 80 percent by weight Ni and 20 percent by weight Cr.

22. The process according to claim 17, wherein the first layer is deposited by means of plasma spraying and the second layer is deposited by means of HVOF spraying.

23. The process according to claim 22, wherein the step of depositing the first layer comprises depositing a layer of stabilized zirconia.

24. The process according to claim 22 or 23, further comprising the steps of depositing an inner bond coat to be located between the substrate and the first layer, and depositing an outer bond coat to be located between the first layer and the second layer.

25. The process according to claim 24, wherein the inner and the outer bond coat are comprised of NiCr.