In the series, we move on to talking about wet wipe substrate and looking at the fibre types found in wet wipes.
Grab a pack of wet wipes from your kitchen, your dressing table or nursing room, peel the package off and you will get a pile of fabric sheets. The fabric looks like tissue paper but it feels softer. You pick up one piece, stretch it and sense a slight of resilience against your stretching. Oops, it is not easy to tear apart.
Well, Nevermind. But when you fold it up, wipe the light stains away on your sleeve, one sudden pang of laziness gets over you and you are about to flush it right into the toilet by your side.
Well, trust me, you won’t wear a jubilant smile by the time when you foot the bill to have your toilet unblocked. So you had better find a trash can now to have it tossed in.
And that mentioned non-flushable, stubborn fabric with a good sense of absorbency, resilience, softness, and strength is what we called SPUN-LACE: the most commonly used nonwoven fabric in Wet wipes.
I am sure you’ve already had a rough idea as to what the wet tissue substrate and its feature is by a glance over the above passages. Still, let’s have the following overview in detail.
1.Spunlace Definition: What is spun lace nonwoven Fabric?
To know spun lace well you need to know what is Nonwoven since spun-lace is an important type of non woven fabric.(see what is nonwoven below).
The Spunlace process is a nonwovens manufacturing system that employs jets of water to entangle fibres and thereby provide fabric integrity.
In a word, Spun-lace is
(1)composite of different fibres
(2)one type of fabric under the non-woven category based on its manufacturing techniques
2.Typical Fiber types in spun-lace for wet wipes
Here is a list of the typical fibre types that can be found in wet wipes and their properties:
(1)Polyester (PET) & Polypropylene (PP)
These plastic fibres are made through extruding molten polymer through small holes. They are widely used in producing wet wipes as they are renowned for having good strength. The disadvantage to these fibres is they have poor absorbency due to being naturally hydrophobic.
(2)Viscose (Rayon in the USA) & Tencel
These are both made from wood pulp or bamboo pulp and therefore come from a renewable raw material. They naturally have good absorbency and strength properties and are known for their softness. They tend to be used in applications where they prevent irritation to the skin.
The main types of wood pulp are softwood and hardwood; which are 3mm and 1mm in length respectively. They have a high surface area and a flat ribbon-like morphology which gives them good cleaning properties. They also have good absorbency but as a downside tend to have poor strength.
The fibre length of cotton varies greatly with each seed, from 3mm to 30mm. In comparison to Viscose, it has a better absorbent capacity and wicking but it does not have the same level of softness. Cotton is known for its good cleaning properties due to having a flat ribbon-like surface.
The most common fibre combination for spun-lace in wet wipes application is PET+VISCOSE. In fact, With the development of spunlaced nonwoven technology currently, we have adopted some new spunlaced technology to produce Woodpulp Spunlace Fabric which is gaining popularity and is seen as the replacement of some normal spun lace fabric, this fabric has 2 types:
Woodpulp +PET & Woodpulp+PP
This wood pulp non woven fabric is more economic as the alternative substrate for spun-lace wipers.
Finding the right blend
What you will find that is very rarely is a wet wipe made solely out of one fibre. Due to their different properties fibers are blended together at different ratios depending on the situation at hand. A household wet wipe will want more absorbency and strength as opposed to softness.
Cost another factor to take into consideration. Fibres like cotton, viscose, and Tencel can be expensive and therefore depending on the product and the application the fibre blend is adjusted accordingly.
Innovative products and solutions can be created; problems can be solved and needs to be met by incorporating appropriate properties. These properties are often combined to create fabrics suited for specific jobs while achieving a good balance between product use-life and cost. (From Below table you can see properties of different fibres)
3.Pattern types for Spun-lace
There are 3 patterns commonly applied in spun-lace fabric for wet wipes:
Plain, Pearl(Embossed), Mesh type
The plain pattern is more prevalent and widely acceptable on the wipes market. Which pattern to choose depends on your likeness and acceptance of consumers, though the pearl embossed pattern does make the wipes look nicer and will thus cost more.