Air Filtration Media NAFA TECH2015 April 17, 2015 Embassy Suites DFW Dallas, TX Air Filtration Media Review what nonwoven’s are and how they are made At this time most state, You have told me what its not It is easier to start Steven Ogle Instructor

Nonwovens Are Not! Knitted Woven Tufted Typically, do not use yarns Paper What are nonwovens? Unless we are discussing a specific application it is easier to answer with what they are not Not Knitted = tee shirt Woven = canvas Tufted = rug Paper © INDA

What Are Nonwovens? Engineered fabrics Fabric made directly from fibers or resins Manufactured at high speed Competitive cost Excludes most “paper” Many applications Nonwovens are everywhere You typically don’t think about a products components This is a frequently ask question and I have listed many common answers Many times the answer is in multitude of applications where we find them They are all around us everyday we just don’t think about it © INDA

Nonwoven Markets/Applications Disposables: Diapers, medical gowns/drapes/wraps, wipes, dryer sheets Semi-durables: Filters (air, oil, gas) Durables: Automotive, home furnishings, geotextiles Somewhere between disposable and durable NW are some semi-durables. Usually defined as single use but the use is for longer times Filtration is a good example. Your home heating and air conditioning filter is deigned for a 3 month life © INDA

Thousands of End Products Consumer Products; cleaning, health, hygiene and more © INDA

Thousands of End Products The industry usually lists NW’s into two categories based on the types of products they’re used in Durable long life and disposable single use applications They are in your car, your house, your bathroom, and your garage They back your carpet, they add bulk to clothing and they protect you from the environment. It’s also in your wallet! show money………….Crane Paper has supplied mint since 1879 Blend of cotton and linen fibers using wet form technology which we will discuss later today © INDA

Air Filtration Products 3.9% Growth – $13.7MM North America by 2018

Nonwoven Air Filtration Media How are they Made Raw Materials Web Forming Fabric Bonding Converting – Final Product

How Nonwovens Are Made 4 Step Process Select raw material Form a web Bond web into fabric Finish/convert fabric If you remember nothing else I ask you remember this “Almost any NW can be made these 4 steps” 1) Select the raw material 2) Loosely arrangement the material to form a web 3) Bond the web into a continuous structure 4) Finish the fabric for conversion into final form © INDA

Step #1 Material Selection Staple Fiber Natural Man made Polymer Resin This is step #1 of the four step process to make nonwoven products. The fiber used in wet and dry laid webs is usually staple meaning they have a known consistent length because they have be crimped and cut or manufactured to a length that is ideal for the intended process. The fiber is then baled for storage and delivery to the NW manufacturing lines. © INDA

A Word About Fibers! Fiber choice critical to end-product Fiber decisions based on fabric requirements Strength Flexibility Melting point, flexible/brittle temperature (glass transition) Stability toward its environment (i.e., flame, sunlight) Dyeability Cost, availability When deciding on the proper fiber we ask what do we need/want to fabric to do/be? Strength – wet or dry, hot or cold, permeant or temporary The attributes of available fibers are well known and easily obtainable so I will not go deep into them but just highlight a few © INDA

Step #2 Web formation – staple fiber to fabric Carded Air laid Wet laid Web formation – polymer to fabric Spunbond Meltblown SMS Step #2 dry laid staple fiber web forming process Short staple airlay is what you do so we will only be discussing longer staple airlay processes. © INDA

Materials Web Formation Bonding Finishing Finished Products Roll Goods Fibers Polyester Carding Calender Surfactant Nylon Air Laid Through Air Repellent Gowns and Drapes Cotton Cross-lap Hydro Color Rayon Wet Laid Needled Coating Paper Tape (Transfusions) Polypropylene Adhesive Other Pulp None Surgical Sponges Fluff Pulp Bi-component Others This flow diagram shows the 4 steps Step 1 is to select the right raw material or materials Fiber in our case © INDA

What Is a Web? A web is a random structure of loose fiber Dry laid webs made by carding or air laying What is Carding Individual fibers between 1/2”-2” are separated by combing A web is formed with a high degree of fiber alignment What is Air Laid? Individual fibers 1/2” or less are separated & carried by air fiber distribution is very random A staple fiber web has little structural integrity And varying degrees of fiber orientation dependent on the web forming process Carded webs have the most controlled fiber orientation © INDA

Web Carding: Dual Cylinder Higher throughput and more carding with 2 cylinders © INDA

Air Laid Card Notice that like a Card this web former has a main cylinder with workers and stripers to separate the fibers and organize them. BUT instead of combing them of the main onto the floor apron they are blown onto it to randomize the fibers and give them loft/bulk © INDA

Air Laid Short Fiber Like a round flour sifter © INDA

What Is Wet Laid? Fibers, very short, are suspended in water and then collected on a screen, forming the web Water is drained, then vacuumed, then pressed, and finally evaporated with heat Hydrogen Bonding w/paper/pulp © INDA

Wet Laid Process Slurry 0.1%-1% fiber © INDA

Materials Web Formation Bonding Finishing Finished Products Roll Goods Polymers Polypropylene Spunbond Calender Surfactant Polyethylene Meltblown Through Air Repellent Gowns and Drapes Mayo Stand Cover Polyester SMS Hydro Color Nylon Film Needled Coating PLA Other PVA None Head Gear and Booties Face Masks Others Virtually any Spunmelt nonwoven product can be made with this matrix © INDA

What Is Melt Spinning? Extrusion of melted polymers to form fibers and webs Meltspinning: Spunbond Meltblown Just like man made fiber manufacturing © INDA

Spunbond Process Resin in Quench and draft © INDA

Meltblown Process Hot Air attenvates (not like spunbonding) © INDA

SMS Schematic Just like a MB sandwich w/SB bread © INDA

Courtesy of Fiberweb PLC SMS Cross Section SB MB Note diff in fiber diam. Courtesy of Fiberweb PLC

Coform Process You can see the meltblown process as shown before but with a pulp feed, hammer mill and blower to introduce the ground wood pulp into the meltblown stream. © INDA

Step #3 Bonding methods Chemical (adhesive, resin, latex) Needlepunch Spunlaced/hydroentangling Thermal bond Step #3 we will discuss ways of bonding the web to form NW fabrics © INDA

Chemical Bonding (Gravure Printer) This is how Handi Wipes are made. There is a design patent on the Wavy Line print pattern. © INDA

Chemical Bonding (Dip & Nip) Dip & Nip is also called Saturation Bonding Typically, Binder comes in at 40% - 45% solids For Dip & Nip, solids are reduced to 5% + surfactant Fabrics will “pick up” 100% -150% of their weight EXAMPLE: 100 gsm fabric + 100 gsm binder @ 5% solids = 200 gsm of fabric + binder at exit =105 gsm of finished fabric after drying © INDA

Chemical Bonding (Foam Padder) Foam bonding uses very little water-could use binder as received w/ 40% - 45% solids. Use air to dilute the binder DRAW Knife Coater with vacuum to saturate © INDA

Chemical Bonding (Spray) Sample 19 scrub pad filter These are dilute solutions of binder and water. Use this technique on dry-formed-pulp/air laid Courtesy of Roy Broughton

Needle Penetration Show #16 = needles One sided or two sided needling systems with single or multiple boards © INDA

Dual Entangler © INDA

Courtesy of NCRC – NCSU - 2001 Calendar Bonding Web passed between two rolls One or both are heated internally One or both may be embossed Heating via conduction Cooling via convection This technique is the most common for thin light weight webs Smooth roll bonding covers 100% Courtesy of NCRC – NCSU - 2001

Courtesy of NCRC – NCSU - 2001 Through Air Hot air This is very common for highloft products Show samples of high loft Fibers can’t be homopolymer: Web must be a blend of high melt and low melt temperature fibers or Bicomponent fibers Courtesy of NCRC – NCSU - 2001

Courtesy of NCRC – NCSU - 2001 Ultrasonic Bonding Horn Friction between horn and fabric heats fibers under raised points Ultrasonic is not very common-it’s too slow. This is used for finished parts like bag filters Or as an assembly technic to bond two or more thermal plastic components together Anvil Courtesy of NCRC – NCSU - 2001

Step #4 Converting Examples include: Slitting Pleating Molding Sheet cutting Die stamping Perforations for easy tearing Pleating Molding Assembling Folding Packaging

Thank You Steve Ogle 919-793-6411 oglelanding@gmail.com