Construction of Coated Abrasives
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Transcript of Construction of Coated Abrasives
Construction ofCoated Abrasives
Quality from start to finish
Coated Abrasives - Types
Coated Abrasive - Construction
Backing
Make coatGrain
Size coatSupersize(Stearate)
Backing Materials
1. Paper2. Vulcanized fiber3. Cloth4. Combination (paper / reinforcement)5. Plastic film6. Non woven fiber7. Knitted fabric with or without foam
Backing Materials
Backing (g/m²) Thickness (µm) Tensile strength (N/cm)A paper 90 110 100B paper 110 135 140,0C paper 120 150 160,0D paper 150 185 170,0
180 220 200,0E paper 220 250 280,0
250 280 320,0F paper 270 310 360,0
1. Paper backing materials classification according to weight/m
Backing Materials
3. Cloth backing
Cotton cloth Tensile strength N/cm
F or JJ flexible 300
J soft cloth 320
X rigid 500
Y extra rigid 600
Polyester cloth 700
Backing Materials
4. Combination backing
A combination backing consists of heavy paper, which on the coating side is reinforced by a light cloth. The cloth increases the tensile strength and protects the paper from becoming brittle due to bonding material penetration.
Film Specification • Corona treated polyester film• Enables extreme smoothness for coatings compared to traditional
papers• For maximum addition of make coat Corona inline process is used
Untreated paper Latex coated paper Smooth film backing
Backing Materials
5. Plastic film
Backing Materials
6. Non-woven fiber backing
The backing consists of fibers needled punched forming a felt cloth which is impregnated with adhesive and grains. This is forming the product an open flexible structure.
• Unique properties- Dust-free sanding- Non-loading- Flat surface
• Products- Abranet, Abranet Soft, Autonet, HD
Backing Materials
7. Net
Backing Materials
7. Knitted fabric with foam
Flexible open construction enabling transport of water and dust through the backing surface.
Syntetic Grains
Aluminium oxide (Al2O3)Hardness depends on the purity of Al2O3
White 99,9% Pink 99% Semi friable 98% Brown 94%
White corundum is pure and hardest corundum, but also the most brittle sharpest one. Normal corundum contains about 3% titanic oxide, owning a good combination of hardness and toughness. Semi frable is the most common used for flexible abrasives.
Syntetic Grains
Silicon carbide (SiC)Silicon carbide = SiC is harder than corundum, but more brittle. The crystal structure of silicon carbide provides a more regular grain form when compared to corundum. Based on hardness, self-dressing and grain form, it is most suitable for sanding plastic, lacquer and glass.
Zirkonium oxide (ZeO + Al2O3)Zirconium corundum is an eutectic mixture of zircon oxide and aluminium oxide. Zirconium corundum has an extremely tough structure.
ASTM Sieve – F and P Grains
µm ANSI mesh F P µm ASTM mesh F P µm3,00 1200 75,00 200 180 500,004,50 1000 80,00 180 525,006,50 800 90,00 170 150 530,008,40 2500 98,00 150 600,009,30 600 106,00 140 625,0010,30 2000 110,00 120 630,0012,60 1500 120,00 120 710,0012,80 500 125,00 120 740,0015,30 1200 130,00 100 750,0017,30 400 150,00 100 850,0018,30 1000 155,00 90 880,0021,80 800 160,00 100 980,0022,80 360 180,00 80 mm25,80 600 190,00 80 1,0029,20 320 200,00 80 1,0430,20 500 212,00 70 1,1835,00 400 220,00 70 1,2536,50 280 250,00 60 1,3038,00 400 260,00 60 1,4040,50 360 270,00 60 1,4844,50 240 300,00 50 1,7045,00 325 320,00 54 1,7546,20 320 330,00 50 2,0052,20 280 355,00 45 2,1053,00 270 230 390,00 46 2,3658,50 240 415,00 40 2,5063,00 230 220 425,00 40 2,8065,00 220 450,00 40 3,35
Bondings
Bonding materials and their combinations- Natural glue products- Resin over glue products- Resin over resin (full resin) products- Waterproof products- Resin over latex- Progressive Bond™
Make coat
Size coat
Bonding materials and their combinations- Natural glue products- Resin over glue products- Resin over resin (full resin) products- Waterproof products- Resin over latex- Progressive Bond™
Progressive Bond™
The difference in behavior between an abrasive paper with Progressive Bond and traditional coating.
Construction:Paper- Optimised paper weight- Good internal bond- Very smooth surface for coating
Make coat- Progressively increasing hardness of resin from bottom to top.
Grain-Precise grain distribution because of the smooth backing-Better surface finish
Resin size coat-Good adhesion-Hard surface layer-Smooth surface
Open / Closed Coating
Avox P150- Open grain distribution
Jepuflex P150- Closed grain distribution
Stearate Coating
The main purpose with stearate coating, is to minimize clogging (Stearate=supersize)
1. The stearate makes the abrasive surface dirt and dust repellent.
2. The stearate has a lubricating and cooling effect on the sanding, i.e. it minimizes the friction.
3. The stearate fills the structure and cavities where the dust sticks.
4. This results in a more consistent surface finish over the life time of the product as the stearate gradually gets worn off, meanwhile the abrading grains worn.
5. The stearate enables the change in color for the material.
Stearate coat
Stearate Coating
Unstearated product Stearate covered product