Abstract:

Objective When exercising strenuously, the sweat glands in the soles of the feet secrete a lot of sweat. The microbiota of the feet decomposes sweat and proteins in the skin cuticle, resulting in organic volatile gases. Antimicrobial sports socks are commonly used in the market to solve the odor problem. However, antibacterial socks have a limited deodorizing effect, which only kill bacteria on the fabric and on the skin that clings to the fabric. For areas that the fabric cannot reach, the bacteria will still decompose secretions and produce odors, such as toes. Moreover, antimicrobial products can affect the microbiota of the feet, increasing the risk to human health from antibiotic-resistant strains. Therefore, it is necessary to develop sports socks with deodorant performance.

Method In order to solve the odor problem of conventional sports socks after wearing, deodorant polyurethane filaments (DPUF) was used to prepare socks with plating stitch structure in this study. Nine samples with different plating yarn (polyamide fiber, Modal, cotton) and DPUF contents were knitted. DPUF was characterized by scanning electron microscopes and infrared spectrometer (FT-IR) for the morphology and chemical structure. Referring to GB/T 33610.2—2017 ″Textiles-Determination of Deodorant Property-Part 2: Detector Tube Method″, a deodorizing performance testing equipment was set up to evaluate the deodorizing and mechanical properties of DPUF and covered yarn. Deodorizing durability, sensory assessment, air and moisture permeability of socks were also tested.

Results Deodorant rate detection device was set up to test the deodorant properties of DPUF and socks, and it was indicated that, compared with polyurethane filaments(PUF), the ammonia deodorization rate (ADR) of DPUF was increased by 85% and acetic acid deodorization rate (AADR) was increased by 66%. After the wrapping process, the ADR of DPUF/polyamide fiber covered yarn was reduced by 16% and AADR by 2%, and it still met the deodorization standard (≥70%). When the DPUF content was 0%, the ADR of polyamide fiber socks, Modal socks and cotton socks were between 40% and 65%, respectively. This showed that the yarn itself has a certain odor absorption capacity, but none of them met the deodorization standard (≥70%). When the DPUF content reached 4% level, the ADR of polyamide fiber socks, Modal socks and cotton socks were 72%, 83% and 90%, and the AADR were 77%, 83% and 88%, all of which reached the deodorization standard (≥70%), and the effect was still noticeable after laundering 30 times. For every 2% increase in DPUF content, the average ADR increased by 12.67% and AADR by 9.89%. When the DPUF content was 6% level, the ADR growth rates of polyamide fiber socks, Modal socks and cotton socks were 110.00%, 67.27% and 50.77%. The growth rates of AADR were 79.57%, 35.29% and 37.14%. Therefore, the application of DPUF in polyamide fiber socks had the highest growth rate of deodorant performance. Through sensory evaluation, the odor intensity level of deodorant polyamide fiber, Modal and cotton socks were 1, 0.5 and 0, respectively, which were 4, 2.5 and 1 odor levels lower than that of ordinary socks. The air permeability of deodorant socks was better than those of ordinary sports socks.

Conclusion DPUF had good deodorant performance and DPUF/polyamide fiber covered yarn provided excellent deodorization, elasticity and abrasion resistance to socks. By using a small amount (≥4%) of DPUF, the deodorizing performance of sports socks were markedly improved. Moreover, the deodorization effect of DPUF was most significant when applied to polyamide fiber socks.

Key words: deodorant sports sock, deodorant polyurethane filaments/polyamide fiber covered yarn, deodorant performance, deodorant durability, sensory assessment