The only application I am aware of is using tannins to promote self-cleaning (through layering formation) of different kind of surfaces.

Self-healing materials are highly engineered that mimic the functionalities of various natural materials found in the human body (e.g., the healing of skin and bones by the vascular system, Lotus plant leaves and water striders, snake skin ). The self-healing material used is encapsulation technologies to incorporate healing materials. The encapsulated healing materials (Micro or nano particles) are randomly distributed inside the matrix materials. Whenever any kind of damage happened on the surface of the self-healing materials due to mechanical, abrasive, chemical reaction, the encapsulated healing agents release that allow patching up the damage.

The technology has multiple applications in different fields

• Construction materials – Self healing cement
• Paints or coatings– Self healing paints, self-cleaning surface
• New generation of self-repairing, tissue-adhesive and tough hydrogel, Self-healing photoreceptor
• Superoleophobic surfaces that exhibit self-cleaning, antifouling, low-drag, and anti-smudge properties
• Self-healing materials in health care- Biomedical application of self-healing gels
• Bio-inspired Self-Healing Organic Materials - Bio-similar, Self Fixing Assembled Bone-Tendon
• Automotive industry - Self-sealing vehicle tire and sealant composition
• Garment industry - self repairing clothes, Self-cleaning cloths
• Metallurgy
• Communication

Some organizations working on the area

• Ethicon Endo-Surgery, Llc
• Angiotech Pharmaceuticals, Inc.
• Searete Llc,
• Broncus Technologies, Inc.
• Academic institutes across the globe

Some references

• Wear-triggered self-healing behavior on the surface of nanocrystalline nickel aluminum bronze/Ti3SiC2 composites, Applied Surface Science, Volume 436, 2018, Pages 1038-1049
• New self-healing techniques for cement-based materials, Procedia Structural Integrity, Volume 3, 2017, Pages 253-260, 
• Self-healing cementitious materials based on bacteria and nutrients immobilized respectively, Construction and Building Materials, Volume 126, 2016, Pages 297-303
• A strategy for constructing superhydrophobic multilayer coatings with self-cleaning properties and mechanical durability based on the anchoring effect of organopolysilazane, Materials & Design, Volume 141, 5 March 2018, Pages 37-47