The abbreviation PES means polyester. It refers to the most currently used synthetic textile fibre in the world : more than 70 % of synthetic fibres on the market-place are made of polyester. It can be mixed with cotton or wool. On the photo opposite, you have a polyester 600D.
Polyamide is also used to make synthetic textile fibres. It is crease-resistant and almost impossible to be torn , even when it is wet. On the other hand, it is sensitive to heat, which may distort it once and for all. On the photo opposite, you have a polyamide 1680D.
Nylon is a textile fibre that belongs to polyamide types. It was invented in 1935 by the Dupont manufacture (at the origin of Kevlar®). This synthetic textile fibre of high tensile strength is one of the most widespread.
Exclusively made by the brand Mission Workshop, this material contains 500-deniers high tenacity woven nylon, impregnated with polyurethane, which contributes to a good resistance to abrasion and water, while remaining light and supple.
Cordura® is the result of a technology applied to a textile fibre, generally composed of nylon and created by the Dupont manufacture in the nineteen thirties. Originally, Cordura® was used for military clothes. Its resistance to abrasion is up to 3 times higher than for a normal nylon : this is a real advantage when it is used on zones submitted to regular rubbing. On the photo opposite, you have a Cordura® 1000D.
Hypalon® is a textile fibre created by the Dupont manufacture in the fifties. It is well-known for its resistance to abrasion, to chemical compounds, to extreme temperatures and to ultraviolet rays. It’s a material used for numerous inflatable rubber boats such as the so called Zodiac.
Dyneema® is a high density polyethylene : its resistance to abrasion, cuts and ultraviolet rays is very important. It’s notably used to make anti-ballistic elements of protection for military vehicles, helmets, bulletproof vests, and gloves protecting you from cuts. Because of the importance of its molecular mass, it’s quite a rigid material.
The material X-PAC™ is a rolled out material first used by sail makers and conceived by the German manufacture Dimension-Polyant. It is waterproof, resistant to tearing and very light.
Cotton is a vegetal fibre, ordinarily converted into threads, then woven to produce material. Cotton is the most manufactured natural fibre in the world, mainly in China and in India. The most important quality criterion is the length of the fibre (the size varies between one and four centimeters, depending on the species) : the longer the cottons are, the thinner and the easier they are to be turned into threads.
Wax-based cotton is a cotton impregnated with a paraffin-based or natural beeswax-based wax, woven or spread on the material. Largely appreciated for being waterproof, it has been much used in England and Scotland since the middle of the 19th century.
Vinylon F is a synthetic material created by the brand Fjällräven. When Vinylon F fibres become wet, they swell and doing so tighten the weaving. That way, they resist showers without requiring a particular wrapping. Cleaning instructions.
Mesh material is composed of a more or less narrow network of threads, generally square-crossed as it is for a net. It allows some air to spread through and, rolled on foam-rubber, it remains very flexible. This composite is very often used for the parts of the bag that come into contact with the body : notably the back.
D like in Denier
When it is indicated that a material is 900D, it means that it is composed of 900-denier threads. The denier is a linear unit of weight. Indeed, a 1-denier thread is a thread of 9000m that weighs 1 gramme : 1 denier = 1g / 9000m. What you must remember is that, though deniers aren’t the only quality criteria, they constitute a very interesting reference : the more important the deniers are the more resistant to abrasion the bag is. For example, a material used for making a lining inside a bag will be rather inferior to 600D. As for the most resistant polyesters, they will have linear masses between 900D and 1680D. However, the more important the deniers are, the heavier the material is. That’s why, polyester can be replaced by polyamide or Cordura® materials whose resistance to abrasion is much higher. So, using a polyamide 600D as a main material instead of a polyester 1680D will be possible.
A « ripstop » type of material is an « anti-tearing » material, or rather a material that stops tearing. That is to say : its squared architecture or its pattern of raised hexagons, will permit the tearing to be hindered : the material is crossed by a thread which consolidates it. The weight of a ripstop material is of great interest : of equal resistance, ripstop will be lighter than a material whose architecture is standard. It can be composed of polyester and / or polyamide.
TREATMENTS & PROCESS
Polyurethane is a polymer (plastic substance) often used as coating on other materials (polyester for example) for its good quality elasticity and resistance to dampness. The materials on which it is spread become waterproof.
DWR means « Durable Water Repellent ». It’s a water repellent treatment spread on the outer layer of the material. The DWR polymer is absorbed by the fibres of the external material and reduces the tension of surface of the material : the water stands out on the material instead of being absorbed. This treatment isn’t permanent but you can renew it any time if necessary.
High welding frequency
High welding frequency can be used to seal two plastic layers. A high frequency current (generally 27,12MHz) makes the substance melt. This technique makes it possible to assemble two panels while maintaining their waterproof quality (contrary to the seam for example).
The bartak stitch is a winding seam. What makes it different from the straight stitch is its shape and its better resistance to constraints. This type of seam is frequently used in the most often solicited places : on shoulder straps, on equipment-rack straps or to strengthen some zip seams.
YKK and Duraflex
The two most famous accessories manufacturers are YKK and Duraflex, respectively based in Japan and in China. For many years, their technical innovations have allowed manufacturers to improve their products. Thus, the use of buckles, strap adjusters, clips or zips of the brand YKK and Duraflex on your rucksack, is a guarantee of quality and durability.
The zipper was invented at the end of the 19th century by American engineers. There are more than a hundred of different types, varying according to their size (#3, #4, #5, #8, #10), their components (plastic, metal, nylon) and whether they are waterproof or not.
The binding is a two ply strap which is used to protect some seams and hide the sewing together of two materials. Its use is often the guarantee of some quality : it preserves the seams and the material from wear and tear and contributes to the rigidity of the bag.
The « piping » is a plastic tube, situated between two materials, designed to strengthen their sewing together : it protects them from wear and tear and makes the structure of the bag become more rigid.
The word M.O.L.L.E. is an English acronym for Modular Lightweight Load-carrying Equipment. The miltary bulletproof vests and tactical rucksacks are often covered with those sewed horizontal fastening stripes of flat buckles, on which various accessories can be fixed (pouches, holsters …) The advantage of this system is its modularity : the user is able to place his equipment where he wants to on his rucksack.
The roll-top fastening is a waterproof fastening : as its name indicates, you close the bag by rolling the top . That way, water can’t seep into it.