Test 3 Flashcards
what is a web
soft, flexible, porous material that lacks strength and durability
why was chemical bonding so popular when it started?
because we had used chemicals on other things before
what was the problem with resigns and glues?
makes it very stiff
what is the best way to use resign?
only use a little at the crossover points to leave pore spaces open
what does chemical bonding struggling with?
balancing stiffness but still being strong
In chemical bonding the fabric can only be as strong as what
the binder
what can binders do over time?
discolor fabrics as they get older
cross linkables need what
a linking agent
process of using binders?
we apply binder then remove water or solvent with heating
what is in an aqueous solution?
monomers, catalyst, and an initiative to get the process started which will come together to make a polymer
what are most chemical binders made from?
water-bone latex so its easier to remove the liquid
what percent is the binder applied on?
5-60%
if we are only using chemical bonding what do we need?
higher levels of chemicals
how does saturation bonding work?
submerge fabric in solution, nip rollers will squeeze out excess,
do we get more absorption with padding or saturation?
padding
what is print bonding used for?
put a pattern
what does foam bonding work well with
thick fabrics
what is power bonding
disperse on fabric and then goes through. oven to bond together
what is a drum dryer
heat fabric over drum and pull through with a vacuum
what is a floation dryer
on conveyor belt and blows hot air
what is the downfall to the infrared oven
not the best choice because it gets so hot that if we have to stop equpiment we will lose everything under it
what is the infrared oven best used for
to preheat fabrics
advantages of chemical bonding with medical textiles (4)
wet and dry strength, soft, not irritating, absorpent
advanatges of chemcial bondinf wirh interlingin (3)
can adjust TG, good hand strength
advantages of chemical bonding with roofing (2)
long term weather ability, hot strength
advantages of chemical bodning with filters (3)
pleat ability, solvent resistance, flame retardant
advanategs of chemicla bonding with furnitaure (3)
color, outdoor durability, compression recovery
how does thermal bonding work?
fibers are bonded by heat, than we cool and wind on a roll
what products are best for thermal bonding?
thick high loft webs
why do we not want fabrics to melt in thermal bonding?
if they melt they will stick to the roll, we want them to soften enouhg to get the chain motion
how do fibers stick together in thermal bonding?
we et flow at fiber to fiber crossover points then soft enough to stick together
where do we bond with thermal bonding
at crossover points
how do we get chains entangled?
we heat them up enough for them to get tangled to the point of being unable to get untangled
how many chain entanglements do we need for the fabric to be bonded?
2
what are the fiber requirements for thermal bonding
need a thermoplastic fiber or some sort of blend with a thermoplatic finfer
what are the 3 binders for thermal bonding
fibers, powders, webs
what are the 4 types of thermal bonding
calendering, thru air, ultrasonic, infrared
what is confuction and which type of thermal bonding uses it
heated by 2 objects touching
calendering
what is convection and what type of thermal bonding uses it?
air is heated
thru air bonding
what is radiation and what type of thermal bonding uses it?
light carries heat
ultrasonic
what si work and what type of thermal bonding uses it?
rubbing 2 things together
ultrasonic
what is calendering bonding
heated fabric will pass through hot rolls
how are mechanical propoerties determined by calender bonding
bond pattern what is pattern of rolls how big is bond area distance between bonds perfect of fabric bonded
more crossover points =
more bonding and stiffer
how is cooling normally done for calendering bonding
with room temperature air at high speeds
what is area bonding
every crossover point in bonded
what is point bonding
heat applied in a specific location
what percent is normallyu bonded through point bonding
10-40%
how many rolls will normally be embossed if any are?
1
what does putting a pattern on your fabric affect (4)
bond to bond distance
percent of fabric bonded
strength
stiffness
why do we need to worry about the temperature of the rolls in calender bonding
dont want them to be too hot and melt
what are the 3 things we need to worry about with calender bonding
temp of rolls
nip line pressure
how long fabric is between rolls
what do we need to worry about with nip pressure in calender bonding
we need good pressure to allow bonding
if we decrease pressure in the nip rolls then what needs to happen
increase heat
how does thru air bonding work
cool fabric goes around perpetrated cylinder with hot air blowing on it and then traveled through air to cool
how is air blown from thru air
blown from outside in or inside in
what are the pros of thru air (2)
maintain loft, flexible frabic
what kind of bonding is thru air
point bonding
how does ultrasonic bonidng work
will vibrate and rub up agaisnt each other to genreate heat
where does vibration happen with ultrasonic
the horn
what is the problem with radiation bonding
temp is too high, if machine breaks down we lost all fabric in it
what is radiation bonding used for
preheat fabric.
what processes can thermal bonding be used on
all web laying processses
is calender or thermal bonding cheaper
thermal
how does needlepunching work
interlocking fibers with abrbed needles, with a lot of compression while icnreaseing fiber to fiber frcigtion
can we control how mnay times a needle is punches in the same space
no
difference between single reduced needle and doubke reduced neefle
single reduced will have one taper, double reduced needle wll we used for a fine fiber
what is the crank
hooks in the board, keeps needle in the board
what is the shank
still in the board and helo with stability
what is the tape
makes less of needle going inot the web. no big holes
what is the point
very tip of needle, designed for minimal needle damange and fiber damange
what is the kick up
how far barb sticks out
high kick up and good barb depth do what
hold more fibers
what are the good things about open barb
not a lot of damange, fabric permeability
conventionally throated barb
agressive when new, used for fibers with high cf, will wear quickly
good thinfs about high life barb (3)
less fiber damange, better hand, dont wear as fast
good things about radius flow barb (4)
more expensive, strong fabric, good surface quality, better entangled
more barbs are what
harsher
small barb spacing =
higher needle effiency but rougher fabric
what needles are used for gentle needling
compact and dense barb needles
what is crown needling
1 barb
needles with short working part =
poor surface quality
what is vario barb
increase kick up size w needle, first barb is the smallest, reduces force
what is a diamond shape needle
barb on 2 sides, shares force, less expensive, less tension on needled
what is a crossbar
barb on all sides, more force
why would we add coating to a needle
to increase needle life
which type of patter needle is most common
fork needling
what does a pattern needle do
forms loops on surface of the fabric
what was hydroentanglinf inspired by and why
needlepunching but wanted to not have as rough of a surface
what is spun lacing
staple fiber web that has been hydroentagling
how does hydroentangling work
on converyor belt then passed through water jet then pressed down
what do the water jets casue
the fibers to wrap around each other
why is hydroentanling goof
feels more like a fabric and smooter
what does the manifold do
hokd the water and create pressurizied water
why do we need a fitler for hydroentangling
so we can have high quality water that doesnt wear out our jet strip
how many nozzles per inch are on the jet strip
40-50
what does hydroentangling cause
jet streaks
how is the pattern caused for hydroentagling
the negative image of the belt
what kind of fibers do you want to use for hydroentagling
flexible fibers that are long enough, fine fibers
what weight of fabric works best
lightweight 20-300 g/m
if a nonwoven worn how is it bonded
hydroentagnling
3 main factors that contribute to hydroentangling
water pressure, enegry transfer, and web support system
why is energy transfer important in hydroentanlgin
need water jet to go to fabric so they woll engtang ebut too muhc energy will create holes
why is web support consided in hydroentangling
because belt image will go on fabric and that can affect the properoties
what is the nozzle made up of
oepn section called capillary and combed section
small hole on top =
cone down nozzle
large hole on top=
cone uo nozzle
why is breakup length important
we want the stream to stay pencil like as long as possible
which cone down or up has longer breakup length
cone down
why do cone up and down behave differently
when water comes around corner if it reattches to the wall itll cause frcigion betwen the water and the wall and you wont get a steady stream
what does non constricted mean
water is attched to the wall
what does constricgted mean
water foesnt attach to the wall and theres air between it
what si the discharge coefficient
measure of jet siamter, what comes out of nozzle
which owrks better cone fown or up
cone down
what are cone up nozzles good for
prewweeting
needlepunching can be done on a carded web as long as its been
crosslapped
