Sunblocks are materials used in creams to help limit exposure to UVA and UVB. Many sunscreens contain TiO2 and ZnO as the primary sunblock materials. In this study, we manufactured a sunscreen lotion using hydroxyapatite (HAp) nano-sol instead of ZnO and TiO2. HAp is a biomaterial widely used in applications such as bone grafting, so it is known to be very biocompatible. In the present work, HAp-water nano sol, ZnO-water nano sol, and TiO2-water nano sol were prepared by the attrition milling method. The sunscreen lotion base (LB) was manufactured with some oil and water. Lotions with various HAp-water solutions and LB concentrations were fabricated and their UV absorbance was measured. 6 % HAp content was the optimal amount considering price. The sun protection factor (SPF) value at that level was approximately 20 on average, corresponding to about 95 % UV protection. Results confirmed that ultraviolet screening agents using HAp had an excellent ultraviolet blocking effect.

Abstract
1. Introduction
2. Experimental Procedure
    2.1. Materials
    2.2. Preparation of the Sunblock materials (HAp,ZnO, and TiO2)-water nano sol
    2.3. Preparation of Sunscreen Samples
    2.4. UV absorbance test
    2.5 SPF (Sun Protection Factor) test
    2.6. White turbidity test
3. Results and Discussion
    3.1. XRD and EDS of Hydroxyapatite
    3.2. Particle size and UV absorbance of Sunblockmaterials (HAp, ZnO and TiO2)
    3.3. UV absorbance of Sunblock materials accordingto HAp ratio
    3.4. White turbidity
    3.5. SPF (Sun Protection Factor)
4. Conclusion
Acknowledgement
References
Author Information

• Su-Chak Ryu(Department of Nanomechatronics Engineering, Pusan National University, Pusan 46241, Republic of Korea)
• Jae-Hun Jeong(Department of Nanomechatronics Engineering, Pusan National University, Pusan 46241, Republic of Korea)
• Dong-Hun Lee(Department of Nanomechatronics Engineering, Pusan National University, Pusan 46241, Republic of Korea) Corresponding author