**4. Final Considerations and Future Perspectives**

The increasing use of CDs in the textile industry is the result, among other factors, of the versatility of these cyclic molecules and the benefits of their use across the productive chain of this sector. Their unique ability to form an inclusion complex with a wide variety of molecules allows their use in several sectors. CDs are able to include dyes, repellents, insecticides, essential oils, caffeine, vitamins, drugs and surfactants, among other substances. Although they are used in the spinning and pretreatment areas, it is in the dyeing, finishing, and water treatment processes that β-CD and its derivatives have the greatest applicability.

The advantages of using CDs in dyeing include changes in bath exhaustion, color uniformity, less effluent treatment, dye savings, and the fact that they are biodegradable. They can be used as a dyeing aid, or as a surface modifying agent that absorbs more dye.

With regard to finishing, different types can be made with CDs, expanding the range of applications for these textiles and giving rise to a new class of materials called functional or intelligent textiles.

It is foreseeable that the use of CDs will continue to expand to keep up with the demands for differentiated products, and fill the gap that still exists in the literature around their application in the textile area, aiming at the optimization of the processes and viable results for industrial use.

This functionalization of CDs in substrates opens the door for the development of new products, such as medical textiles. With the new reality caused by the SARS-CoV-2 pandemic, the development of antiviral textiles is on the rise, and many of these new materials could be generated from technologies that use CDs. Furthermore, the transposition of new medical treatment technologies into textile materials from CDs is already a reality. An example is the use of β-CD for the development of textiles aiming at the photodynamic inactivation of microorganisms.

Finally, the capacity of CDs to adsorb and separate pollutants (dyes, metals, surfactants, etc.) from industrial waste is important with regards to environmentally sustainable industrial processes. In addition to adaptability and ease of operation, their biodegradability and lack of toxicity make CDs stand out in different areas.

Without a doubt, the use of CDs in basic and applied research around the development of new materials is fundamental, and should be the focus of many future studies seeking sustainable alternatives in the textile area.

**Author Contributions:** Conceptualization, F.M.B.; methodology, H.B.F., R.d.C.S.C.V. and J.A.B.V.; investigation, H.B.F., J.G.D.d.S. and F.A.P.S.; data curation, R.d.C.S.C.V. and J.A.B.V.; writing—original draft preparation, F.M.B., H.B.F., J.G.D.d.S. and A.L.T.; writing—review and editing, M.J.L., R.d.C.S.C.V., J.A.B.V., F.A.P.S. and A.L.T.; visualization, H.B.F., J.G.D.d.S., F.A.P.S. and A.L.T.; supervision, F.M.B.; project administration, F.M.B. and M.J.L.; funding acquisition, M.J.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Acknowledgments:** INTEXTER-UPC, UTFPR-AP and National Council for Scientific and Technological Development (*CNPq*). The author José Alexandre Borges Valle are grateful to CAPES-PRINT, project number 88887.310560/2018-00.

**Conflicts of Interest:** The authors declare no conflict of interest.
