Introduction to Covered Yarn

I. Product Application Scenarios

With its excellent elasticity and fit, covered yarn has a wide range of key applications in the hygiene product field, as detailed below:

(I) Sanitary Napkin Field

It is mainly used in the 3D three-dimensional structure part of sanitary napkins, combined with spandex yarn. This combination can significantly enhance the anti-leakage effect of the product, fit the human body curve closely, effectively avoid leakage problems caused by displacement, and improve the sense of security and comfort for users during use.

(II) Diaper Field

In diapers, covered yarn is mainly applied to the core structural parts on both sides, involving a total of two key areas and four specific application points. Its core function is to provide anti-leakage contraction effect: on one hand, it tightly wraps the baby’s body through precise contraction force to block the side leakage channel of urine; on the other hand, compared with traditional elastic materials, its soft contraction performance can avoid oppression on the baby’s delicate skin, reduce skin discomfort, and allow the baby to move more freely.

II. Basic Product Description

(I) Product Definition and Core Advantages

Covered yarn is a functional yarn made of spandex or latex as the core thread, with the outer layer wrapped by various nylon or polyester fibers. Its core advantages are prominent: it has high elasticity and good flexibility, can stretch naturally with movements when fitting the human body without a stiff feeling; at the same time, it has excellent wrinkle resistance, is not easy to wrinkle after long-term use or storage, and always maintains the neat appearance and stable structure of the product. Therefore, it is widely used in the hygiene product field.

(II) Specification Parameters of 720dtex Spandex Covered Yarn (720D) for Diapers

To ensure the stability and reliability of the product in diaper applications, we have conducted strict performance tests on the 720dtex spandex covered yarn. The test results and specification requirements are shown in the table below. All indicators are better than the standards and can fully meet the usage needs of diapers:

Inspection Item	Specification Requirement	Actual Test Result
Elongation at Break (%)	910±80	900.38
Tension at Break (CN)	≥580	596.41
Stress at 300% Elongation (CN)	≥85	92.08
Elastic Recovery at 300% Elongation (%)	≥96.5	97.09
Oil Content (%)	1.5±1.0	1.68
Net Weight per Cone (g)	3000	3060

III. Core Product Characteristics

(I) Uniform Tension and Stable Structure

Each covered yarn is made by combining multiple spun yarns. During the production process, precise tension control technology is adopted to ensure uniform tension of each yarn. This uniformity not only makes the overall structure of the yarn more stable but also avoids problems such as elastic failure or product deformation caused by uneven local tension when processed into hygiene products later.

(II) Strong Elasticity and Excellent Performance

In terms of elastic performance, covered yarn has obvious advantages: the resilience per denier (g/10000m) is 3 times that of ordinary elastic materials (the elasticity of ordinary elastic materials is about 0.024g/unit). The strong resilience can ensure that hygiene products can quickly return to their original shape even after repeated stretching during long-term use, maintaining the anti-leakage and fitting effects.

(III) Stable Stress-Strain and Good User Experience

The stress-strain curve of covered yarn shows excellent smoothness, especially in the effective elongation range of 20%-30%, which can maintain stable and uniform resilience. This means that when the product fits the human body, there will be no tightness or looseness caused by sudden increase or decrease of elasticity, and it always provides users with a comfortable and stable wearing experience.

(IV) Wide Elongation Range and Strong Adaptability

It has a wide elongation range, and the design specification of elastic force can flexibly cover the elongation range of 2.0-4.0 times. This high adaptability enables it to meet the design needs of different types and sizes of hygiene products. Whether it is products for adults or infants, it can accurately match the elastic requirements and improve the overall adaptability of the product.

IV. Core Product Advantages

(I) Skin-Friendly and Safe, No Allergy Risk

It uses nylon, polyester outer materials and spandex/latex core threads that meet the hygiene industry standards. All raw materials have undergone strict safety tests and do not contain harmful and irritating components. When in contact with human skin, it will not cause allergic reactions, which can fully protect the skin health of infants and adult users, and is especially suitable for people with sensitive skin.

(II) Soft Elasticity, Comfortable Without Tightness

The elastic retraction force is designed to be soft and uniform, and it will not cause oppression when fitting the skin, effectively avoiding poor blood circulation caused by tightness. Whether it is the baby’s activities or the adult’s daily movements, it can maintain a comfortable wearing experience.

(III) High Temperature Resistance and Easy Storage

It has a certain high-temperature resistance and is not easy to deteriorate in performance under conventional processing and storage environments; at the same time, hygiene products such as sanitary napkins and diapers made of this covered yarn have a longer storage period. Even after long-term storage, they can maintain good elasticity and anti-leakage effects, reducing the product loss rate.

(IV) Meeting the Core Needs of the Hygiene Industry

It fully meets the strict requirements of the hygiene product industry for elastic materials: it not only has moderate elasticity to accurately match the product fitting needs; but also has excellent creep resistance, so it is not easy to have elastic attenuation or deformation after long-term use; at the same time, it has good aging resistance, and always maintains stable performance within the product shelf life, providing a strong guarantee for the quality of hygiene products.