TECHNOLOGY AREA(S): Materials/Processes

ACQUISITION PROGRAM: Naval Clothing Textile Research Facility

OBJECTIVE: Introduce new, improved knit technology to provide more comfortable knitwear for the Sailor by improving fit, increasing air permeability, wicking away moisture, reducing seams and chafing, reducing bulk, and providing the potential for increased protection (Flame Resistant (FR) and No Melt/No Drip) while reducing waste and saving time and money for the Government.

DESCRIPTION: The technology used in current Navy knit garments is known as �cut and sew.� A knit fabric manufacturer creates yardage of a knit fabric to a specification and that fabric gets tested to ensure it meets standards, which include but are not limited to, colorfastness, tear strength, launder-ability, and shade matching. Once the fabric is approved for use in a Navy item, it is shipped to the garment manufacturer to �cut and sew� the knit item. The construction process typically uses multiple operators to perform various functions: one operator to cut, one operator to stitch the sleeves, one operator to stitch the collars, and more operators to complete a number of other tasks. If the item uses multiple fabrics to offer different technologies such as compression, air permeability, and wicking, then these materials are separate rolls of fabric that must also be purchased, tested, cut, and sewn into that garment. If the item has embroidered logos, yet another step is added to the process. If the item has a heat transfer logo, it is purchased from another company and then adhered by the manufacturer. End-item testing is required to ensure that heat transfer logos are properly adhered.

Newer, seamless circular knit machines utilize a technology that is currently used commercially to produce items such as, but not limited to, T-shirts, leggings, shorts, underwear, shapewear/compression, and maternity-wear. These machines specialize in producing engineered panels within one tube with multiple stitches, such as jacquards, ribs, or special textures. This capability requires less labor and creates less fabric waste. Seamless knitting can integrate embroidery and customize the placement of yarns to offer varying permeability and knit construction options within one garment. Yarns such as Nylon/spandex or poly/Nylon/spandex are most commonly used, but �green� yarns, highly technical moisture management, and anti-bacterial yarns have also been used. Various yarns such as Flame Resistant (FR) and No Melt/No Drip compositions do not currently exist with multi-fiber blends This technology would be best utilized in the Navy�s base layer systems and physical fitness uniforms. One person can operate four machines at a time. Each machine makes the entire garment from beginning to end. There is no unusable waste fabric because the knitting process makes the garment instead of just making the fabric. The garment would only need to be tested once at the end of production to yield result data for quality assurance in areas such as colorfastness, tear strength, launder-ability, and shade matching. These seamless knitting techniques would save the Navy both time and money.

PHASE I: Provide an initial research and development effort that demonstrates the scientific merit and capabilities of applying seamless knitting techniques with FR and No Melt/No Drip composites to military knitwear with a concentration on protective clothing. Develop initial concepts and evaluate their technical feasibility. Compare promising concepts to traditionally sewn seams using a variety of internationally recognized standards and test methods such as those referenced in the American Association of Textile Chemists and Colorists (AATCC) and American Society for Testing and Materials (ASTM) International to determine the most appropriate candidate technologies prior to down selection and subsequent assembly of pre-prototype garments. Develop a Phase II plan.

PHASE II: Optimize the proposed concept(s) and produce prototypes for preliminary evaluations. Conduct material and system-level evaluations against all test methods deemed necessary by Textile Technologists for the end use of the garment. Develop conceptual prototypes to demonstrate and evaluate the suitability of the technology in a field evaluation.

Design, develop, and test prototype garments utilizing the best candidate seamless knitting technologies selected from Phase I. Conduct a manufacturing feasibility analysis using a standard Navy garment as a demonstration model, which utilizes seamless knitting techniques and would be an excellent example to assess the technologies� viability. Subject prototype garments to laboratory durability prediction assessments using multiple home and/or shipboard launderings, prior to user evaluation. Select garments will be considered for a limited shipboard and shore side user evaluation. Following the wear test, evaluate the prototype garments through objective laboratory assessments and by collecting user feedback through focus groups to determine performance, durability, reduction of bulk and weight, operational compatibility, and ease of care.

PHASE III DUAL USE APPLICATIONS: Provide support in transitioning a seamless knitting technology into appropriate Navy garments. Develop a plan to determine the effectiveness of the re-engineered clothing items in operationally relevant environments. Support the Navy with certifying and qualifying the clothing for Navy use.

There are a wide range of DoD uniform items that this technology could improve including: physical fitness uniforms, T-shirts worn under utility and dress uniforms, base layers, and other undergarments. Further research and development on this knitting technology with FR and No Melt/No Drip yarns to create protective clothing could result in ideal garments for Navy use.

Interest in this technology has also been shown by the Joint Service Chem/Bio clothing group for a knit undergarment top and pants so that there are less seams where leakage can occur, and by NAVAIR for a seamless base layer system to reduce bulk and chafing. The Marine Corps has also shown interest into this technology to incorporate padding in knitwear (i.e., elbow pads). The application of FR and No Melt/No Drip yarns to protective clothing would be beneficial to fire fighters, electricians, welders, and anyone else working in a high risk, high heat environment in the commercial sector.

REFERENCES:

1. NCTRF PD 14-06 Jersey (Mock) (Navy Clothing & Textile Research Facility), http://www.public.navy.mil/bupers-npc/support/uniforms/uniformregulations/uniformcomponents/Pages/3603_7.aspx

2. NCTRF PD 17-15 Trunks, Physical Fitness Uniform (liner), http://www.public.navy.mil/bupers-npc/support/uniforms/uniformregulations/uniformcomponents/Pages/3601_6.aspx

3. NCTRF PD 16-15 Undershirt, Physical Fitness Uniform, http://www.public.navy.mil/bupers-npc/support/uniforms/uniformregulations/uniformcomponents/Pages/3601_2.aspx

4. A-A-50013 Undershirt, http://www.public.navy.mil/bupers-npc/support/uniforms/uniformregulations/uniformcomponents/Pages/3603_2.aspx

5. American Association of Textile Chemists and Colorists (AATCC) - https://www.aatcc.org
(AATCC 8 - Colorfastness to Crocking: AATCC Crock-meter Method; AATCC 15 - Colorfastness to Perspiration; AATCC 16 - Colorfastness to Light; AATCC 61 - Colorfastness to Laundering, Home and Accelerated; AATCC 81 - pH of the Water-Extract from Wet Processed Textiles; AATCC 88B - Smoothness of Seams in Fabrics after Repeated Home Laundering; AATCC 100 - Antibacterial Finishes on Textile Materials, Assessment of; AATCC 135 - Dimensional Changes of Fabrics After Home Laundering AATCC 197 -Vertical Wicking of Textiles; AATCC Evaluation Procedure 1, Gray Scale for Color Change; AATCC Evaluation Procedure 2, Gray Scale for Staining; AATCC Evaluation Procedure 6, Instrumental Color Measurement; AATCC Evaluation Procedure 8, AATCC 9-Step Chromatic Transference Scale; AATCC Evaluation Procedure 9, Visual Assessment of Color Difference of Textiles)

6. American Society for Testing and Materials (ASTM) International - https://www.astm.org
(ASTM D737 - Standard Test Method for Air Permeability of Textile Fabrics; ASTM D3512 - Standard test method for Pilling Resistance and other related Surface Changes of Textile Fabrics: Random Tumble Pilling Tester; ASTM D3776 - Standard Test Method for Mass Per Unit Area (Weight) of Fabric; ASTM D3787 - Standard Test Method for Bursting Strength of Knitted Goods Constant-Rate-of-Traverse (CRT) Ball Burst Test; ASTM D3887 - Standard Specification for Tolerances for Knitted Fabrics; ASTM D6193 - Standard Practice for Stitches and Seams; ASTM D6797 - Standard Test Method for Bursting Strength of Fabrics Constant- Rate-of-Extension(CRE) Ball Burst Test; ASTM E2149 - Standard test Method for Determining the Antimicrobial Activity of Immobilized Antimicrobial Agents Under Dynamic Contact Conditions; ASTM D6413 - Flame Resistance, Flame, Glow, Char- Before and After Laundering)

KEYWORDS: Clothing; Seamless; Knitting; Garment; Yarn; Technology; Military Protective Clothing; Material; Fabric