N231-002 TITLE: Seamless Knitted Mesh, Cold Weather Baselayer Undershirt and Drawer

OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Advanced Materials

OBJECTIVE: Develop a seamless undershirt and drawer that could replace the current, conventionally cut and sewn mesh, cold weather baselayer undershirt and drawer.

DESCRIPTION: The Marine Corps recently developed and is fielding a new cold weather, mesh baselayer undershirt (MIL-DTL-MC033) and drawers (MIL-DTL-MC032). The current garments are constructed through conventional cut and sew technology and use three different fabrics: a mesh (MIL-DTL-MC034), jersey (MIL-DTL-MC035), and rib knit (MIL-DTL-MC036). The items are for use next to skin in extreme cold weather. The mesh structure provides standoff between a Marine�s skin and other layers to allow for evaporation of sweat and creation of air pockets, keeping the wearers dry and warm.

The technology used to construct the current garments is known as "cut and sew." Knit fabric manufacturers produce fabrics to specifications and test the fabrics to ensure they meet certain requirements, which includes, but is not limited to, construction, colorfastness, burst strength, launder-ability, and shade matching. The cold weather, mesh baselayer undershirt and drawers are constructed with three fabrics, a mesh, jersey, and rib knit, meaning the three fabrics in the current manufacturing method must be produced separately. Once the fabrics are approved for use, they are shipped to the garment manufacturer to cut the fabrics, based off a pattern, and sew them together to create the undershirt and drawer. The cut and sew process typically uses multiple operators to perform various functions: one operator to cut and multiple operators to stitch the pieces together.

Newer seamless v-bed knitting machines utilize technology that allows for knitting and garment formation such as, but not limited to, T-shirts, leggings, shorts, underwear, compression, and maternity-wear, on one machine. This technology is used extensively in Asia and is slowly becoming more common in the US. There are two main manufacturers of seamless v-bed knitting machines: Shima Seiki and Stoll. These machines specialize in producing engineered panels or tubes with multiple stitches, such as jacquards, ribs, or special textures. This capability requires less labor, less factory space, no sewing thread, and creates less fabric waste. Seamless knitting can customize the placement of yarns to offer varying permeability and knit constructions within a garment without seams. One knitting machine has the capability to knit the entire garment, including adding cuffs, buttonholes or openings, collars, etc. There is little to no waste as the knitting process takes the yarn directly from cone to garment, rather than cone to fabric to cut pattern parts to garment.

A seamless garment would only need to be tested once at the end of production, instead of fabric and garment testing, to verify requirements for quality assurance in areas such as construction, colorfastness, burst strength, launder-ability, and shade matching. The manufacturing supply chain would be shortened, eliminating the cut and sewing operations.

Berry Amendment compliance is required.

PHASE I: Conduct research on and determine the performance level of a seamless mesh undershirt and drawer, as compared to the existing mesh undershirt and drawer. Develop initial concepts and evaluate their technical feasibility. Compare concepts to traditionally sewn seams using 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 concept(s) prior to down selection and subsequent assembly of prototype garments. Develop a cost and durability comparison between the current cut and sew base layer and the estimated cost of a seamless mesh baselayer. Develop a Phase II plan for prototype production.

Develop and deliver fabric samples that meet all or most of the three fabric specs and provide fabric level test data comparing the developed samples to the current requirements. Validation/tests should demonstrate where the seamless undershirt and drawer meets and/or does not meet the requirements, as defined in the, Mesh, Cold Weather Baselayer Undershirt and Drawer Detail Specifications [Refs 1 and 2]. Integrate all three types of fabric into one swatch to demonstrate the construction transition. Yarns with fiber content outside of the current specs, (MIL-DTL-MC034), jersey (MIL-DTL-MC035), and rib knit (MIL-DTL-MC036), will be considered if they meet all or most of the fabric specs. Any yarns considered shall meet the No-Melt, No-Drip (NMND) requirement, cannot contain cotton, and must meet most fabric requirements.

Develop the program for a seamless knit mesh base layer and provide a single demonstration model, also referred to as a mockup, of a single seamlessly knit top and bottom. A garment constructed only through seamless knitting is preferred though garments with the finishings linked on, i.e., cuffs or collar, will be considered. Minor garment changes compared to the current baselayer shall be considered if needed to improve manufacturability.

PHASE II: Optimize the proposed concept(s), work with Government entities for initial fit assessment, grade programs to size S-XL, work with government entities for subsequent fit assessments, 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 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. Provide at least 50 seamless sets (undershirt and drawer) in multiple sizes to the Marine Corps for Marine Corps testing and evaluation.

Conduct a US manufacturing feasibility analysis using mesh undershirt and drawer as a demonstration model for the technologies� viability. Subject prototype garments to comparison between current specification requirements and laboratory durability prediction assessments using multiple launderings, prior to user evaluation. Prototype garments will be considered for a Government user evaluation. Following a user evaluation, the government will 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 Marine Corps garments. Develop a plan to determine the effectiveness of the re-engineered clothing items in operationally relevant environments. Support the Marine Corps with certifying and qualifying the garments for Marine Corps use.

There are a wide range of DoD uniform items that this technology could improve including: physical fitness uniforms, T-shirts, base layers, other undergarments, and accessory items such as gloves. Further research and development on this technology could result in follow-on garments for Marine Corps use.

Interest in this technology has been shown by the Joint Service Chem/Bio clothing group for a knit undergarment top and pants to eliminate seam leakage, and by NAVAIR for a seamless base layer system to reduce bulk and chafing. Similarly, the Army has expressed interested in the seamless technology for use in their base layers and the Navy has a current SBIR topic for the seamless manufacturing of the flight deck jersey. The Marine Corps has additional interest in this technology to incorporate padding in knitwear (i.e., elbow pads).

Commercial industries would also benefit from this technology. Sectors such as athletic base layers for cold weather activities, i.e. hiking, climbing, skiing, etc. would be ideal transition partners interested in this technology. Other products that could use this technology could include athletic leggings, winter sweaters, t-shirts, undergarments, gloves, beanie caps, and more.

REFERENCES:

1.       MIL-DTL-MC033, DETAIL SPECIFICATION, UNDERSHIRT, MESH, COLD WEATHER BASELAYER. navysbir.com/n23_1/N231-002-REF-1-DRAFT-MIL-DTL-MC033.pdf � site registration required to access document.

2.       MIL-DTL-MC032, DETAIL SPECIFICATION, DRAWER, MESH, COLD WEATHER BASELAYER. navysbir.com/n23_1/N231-002-REF-2-DRAFT-MIL-DTL-MC032.pdf � site registration required to access document.

3.       MIL-DTL-MC034, DETAIL SPECIFICATION CLOTH, MESH KNIT. navysbir.com/n23_1/N231-002-REF-3-DRAFT-MIL-DTL-MC034.pdf � site registration required to access document.

4.       MIL-DTL-MC035, DETAIL SPECIFICATION CLOTH, JERSEY KNIT. navysbir.com/n23_1/N231-002-REF-4-DRAFT-MIL-DTL-MC035.pdf � site registration required to access document.

5.       MIL-DTL-MC036, DETAIL SPECIFICATION CLOTH, RIB KNIT. navysbir.com/n23_1/N231-002-REF-5-DRAFT-MIL-DTL-MC036.pdf � site registration required to access document.

6.       NAVY SBIR Topic N182-124 Seamless Knitting for Military Protective Clothing navysbir.com/n18_2/N182-124.htm

7.       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. American Association of Textile Chemists and Colorists (AATCC). https://www.aatcc.org

8.       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. American Society for Testing and Materials (ASTM) International. https://www.astm.org

9.       The Berry Amendment Restrictions for Clothing, Fabrics, Fibers, and Yarns, https://www.trade.gov/berry-amendment

 

KEYWORDS: cold weather clothing; mesh knit; underlayer; base layer

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