Anodize Literature

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KHATAU VALABHDAS & CO., INDIAN GLOBE CHAMBERS, 142 D.N.ROAD,BOMBAY 400 001 INDIA.

PH. (91-22) 22611656 FAX (91-22)-22611655 EMAIL [email protected]

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KEVILUMINIUM DYES AND CHEMICALS

FOR ANODIZED ALUMINIUM

Generally the purest from of Aluminium is recommended for anodizing but the commercial grade ofaluminium is generally used. The anodizing of aluminium takes place in the following stages: -

1) Cleaning and Brightening.

2)

Anodizing.

3) Rinsing & Neutralizing.

4) Dyeing with Keviluminium Dyestuffs.

5)

Rinsing & Cleaning

6) Sealing & Drying

1) Cleaning and Brightening

We can recommend Keviclean PRG Liquid which can be used to clean aluminium articles.This

product is a highly concentrated product which is used by many industries for the

removal of dirt, grim, protein stains, buffing powder removal etc.The product is very suitable instead of soap and in simple terms can be described as a

powerful liquid detergent. The use of the product is very little and you need to put

only 5 Gms in a litre of water for getting the necessary effects of dirt removal.

We are only selling this product for industrial applications and have been found highlycost effective compared to other similar products available.

This product is fully environment friendly and does not cause any harmful pollutants

and is easily passed under the pollution norms of most countries.The product is multipurpose in nature and can be used to clean floors windows etc. in

mild form.(2 gm/litre only)

The pure chemical is highly effective in even removal of paint from places notrequired. It is not harmful to metals in any way.

Bare hands without a problem can handle the material and it does not cut your hands

like the way caustic does which please note.So when you use it you will find that in the longer run you will save a lot of money as

you will not be paying for the water and unwanted filling materials to be mixed.

In the anodizing industry it is used as a pre cleaner 5 gm/litre before buffing or causticis done and even if the raw aluminium is just stored for 2-3 days.

You should also use the same after doing the buffing, as it is an effective bu ffingcompounds remover without harming the final finish of the product.

This will help in cleaning and not damaging any aluminum, which please note. Use

only 2-5 Gms per litre after buffing, as a stronger solution will make the polishedsurface duller.





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KEVIZIN KVS LIQ.(FUME SUPRESSANT)This product is used to control the emission of Fumes from the anodizing tank and the

caustic tank used for etching purposes.The emission is harmful to the workers and to the environment and to control the

fumes the product has to be put in the tank so that a layer of 6 inches of foam is

formed in the tank, which will control the fumes and save your company from

pollution dept. , helps the workers and keeps the air around you cleaner and healthier.It is our sincere request to you to become aware and to use the products for the

multiple benefits it has to offer you.

Cleaning can also be done in an ultrasound machine for small articles. The use of Keviclean PRG Liq. Isalso recommended in its use as it will be an added advantage in the ultrasound machine.

2) Anodizing -

Normally the anodizing of aluminium articles takes place in an electrolytic bath, as mentioned

below :-

Sulphuric Acid : 20% by wt. Or 28.5 tw.

Anodizing Temp. : 18°C – 20°C

Current Density : 1.5 amp/sq. decimeterPotential Difference : 10 – 20 volts D.C.

The duration of anodizing depends on the type of shade and depth required. For gold (Yellow etc.)

shades normally the anodizing time is 20 – 30 minutes and darker shades like brown’s, black’s etc. The

duration for strong anodizing is about 45 – 50 minutes.

Some anodizers are doing only natural anodizing and they proceed directly to the sealing stage afteranodizing.

During the stage of anodizing there is lot of fume emission, which takes place due to the agitated bath ofsulphuric acid. This caused irritation to eyes and affects the working of the people at this stage. We

therefore recommend the use of our Kevizin KVS Liquid (details mentioned above).

These Chemicals are generally added in required proportion so that a layer of foam is formed

in the bath which helps in controlling the fumes. The chemicals may be added periodically depending

upon the Condition of use.





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3) Rinsing and Neutralizing -

After anodizing the aluminium is thoroughly rinsed in cold water, neutralized with little Soda

Ash/or Ammonia and kept ready for dyeing.

4) Dyeing Keviluminium Dyestuffs -

Keviluminium colours dissolved easily in hot water (free from Iron and Lime). The desiredquantity of dye solution is transferred to the dye bath. It is preferable to use soft water or

distilled water for dyeing.

Dyeing temperature should be maintained between 55 centigrade and 65 centigrade. If the

Colour in not required for stripping purpose then the temperature may be raised even upto 75Centigrade. This may prevent loss of colour in sealing.

The concentration of dyestuffs in dye bath is adjusted according to the shade desired. Normally

for gold shade 0.2 gm. to 1 gm. Per litre is sufficient. For jet Black the bath should contain

minimum 10 gm/litre of dyestuff. For remaining colours,concentration would very from 2 gmto 5 gm. Per litre according to the depth of the specimen.

Duration of Dyeing/PH of Dye bath

Dyeing is usually carried out for 5-15 minutes According to the depth of shade desired. PH of

the dye bath may be kept at around 6. Incase where lower PH is required it can be controlled byaddition of little acetic acid to the dyebath. Particularly blacks, blue and rubine require lowerPH between 4.5 to 5.5. However for Fiery Red SBL please see that the PH is alkaline and not acidic at all

since the product will not work under acidic conditions at times.

5) Rinsing and cleaning

After dyeing there may be additional deposits of colour on the anodized piece if the same may

have been over anodized and therefore the same should be cleaned and rinsed thoroughly after

dyeing. It would be advisable to rinsed under running water or at least 3 to 4 baths should be used to seethat no trace of acid remains before preparing for sealing.

6) Sealing & Drying .

Sealing is an important operation for fixing the colour on the anodic film.There are two methods of

sealing either by hot water or Cold water Sealing.





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Hot Water Sealing Process

After dyeing the articles are rinsed in cold water and immediately treated for sealing in a bath

containing boiling water for 30 minutes.

But sometimes sealing in simple hot water does not fulfill the desired result. To ensure better fastness to

light and weather and to minimize bleeding it is recommended to add any of the following salts to the

sealing bath.

5-7 gm/litre Kevi. Sealofix N-1200

Or

3-5 gm/litre Kevi. Sealofix ZAB

Adjust PH of the bath at 5.5 by addition of Acetic Acid or Formic Acid.

Maintain temperature at the boil or 95 centigrade and continue for 20-30 minutes.

Kevi. Sealofix N-1200 is especially good for blues, browns, blacks etc.but also used for all the products.

The following factors which have influence in better sealing.

A) Water should be pure.

B) Temperature should not go below 95 DegreeC) PH value to be maintained at 5.5.

D) Renew sealing bath from time to time.

After sealing, the articles are rinsed in water, dried, cleaned or polished as desired.

Mid Temp Sealing Process

The cost of energy is also a factor to control and so nowadays we recommend the following procedure of

use too.

Prepare a solution of 10-15 gms /litre of Kevi. Sealofix ZAB and heat until 60-70 degrees centigrade.

Immerse the aluminium for 15-20 minutes only.

In case you can control the water temperature you may maintain the same between 50-70 degrees

centigrade all throughout the day for best results.We have even found that some products are kept for 40-45 minutes in the room temperature solution and

the sealing is adequate at times. The choice is yours to adopt but we always recommend it mid temp.





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Cold Water Sealing Process.

Kevicoat C-600 and Kevicoat C-1800 are water soluble, non in-flammable products with excellentcorrosion resistance properties.

Cold Sealing: - After anodizing of aluminium kindly rinse (Two to Three times) in order to remove alltraces of Acid thoroughly. Just dip the same into ready solution of Kevicoat C-600 or Kevicoat C-1800

(As per concentration required) to get a transparent organic protective coat with weatherproof properties.

It would be better to enhance the drying process between(50oC – 80 o C) by blowing hot air or by centrifugal drying. This process will also eliminate finer print

mark on the anodized surface and will increase the shelf life of the finished products.

Caution :- Kindly avoid immersion of product twice so that streaky appearances can be eliminated and

do not bring the solution in contact with the acids.

Guidelines For Certain Keviluminium Dyestuffs.

BLEEDING

Some dyestuffs have tendency to bleed during sealing, especially when water alone is used. In order to

overcome this difficulty, maintain temperature of dyeing to the extent of 75 to 80 degree C. and dye atleast for 5 minutes. After dyeing for a very brief period, seal immediately.

Otherwise, treat the dyed material for 5 minutes in 20% solution of barium Chloride at 45°C . Thereaftercarry out sealing with Kevi-Sealofix N-1200 or ZAB.

Notes for certain Keviluminium Dyestuffs.

All the Keviluminium Dyestuffs are water-soluble. The depth of the shades can be improved by

increasing the quantity of dyestuffs as desired. Practically the anodizers make one bath for the colourand they replenish the bath with additional dye when desired. When our colours are used without

combinations they are suitable for replenishment except as mentioned under.

Some shades have certain peculiar characteristics.

1. Keviluminium Olive Green BL II

2. Keviluminium Olive Green GRS II3. Keviluminium Green PRG II

4. Keviluminium Bronze BG





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The above shades are very good when they are dyed in the first dye bath that is prepared but when thesubsequent pieces are dyed there will be a slight variation in the shade. This occurs due to absorption of

certain chemicals at a faster rate than others. Even by replenishing more dye into the solutions thedesired effect may not take place. Hence it would be advisable to warn our clients in respect of these products that they should prepare as fresh bath to get the desired shades and to be careful regarding the

percentage and duration of dyeing.

1. Keviluminium Black BGRW

2. Keviluminium Black JBK

3. Keviluminium Dark Black CLPS EXPORT.

The above dyestuffs should be used minimum 10-20 gms/Lts. To get a deep black shade lowerconcentration of these products may not give the desired depth to the shade. Even the anodizing time

given should be increased for the colours.

Kevi. Fiery Red SBL: - Kindly see that the dyeing bath is heated and properly stirred. Kindly do not useAcetic Acid in the dye bath and before putting the anodized piece in the colour see that the same is

properly neutralized.

Kevi. Golden Orange RLG: - This dyestuff is generally used where the shade required is from lightgold to Deep Orange shades. The light gold shade generally gives the appearance of 18 K Gold and is

fast moving in the making of metal labels, chains and imitation jewelry.

Kevi. Gold MKO: - This product has the same characteristics as Kevi. Golden Orange RLG but will

produce different shades of gold and orange. Generally it gives the appearance of 22K Gold and is fastmoving in the making of metal labels, chains and imitation jewelry.

Kevi. Yellow 4GLN: - This product is used by the electrolytic process of anodizing and will produce

shades from light Lemon Yellow to Dark Yellow. This product is extremely useful for architectural purposes and could be very suitable for aluminum windows, channels, doors and other products, which

are exposed to sunlight.

For your general information aluminium anodizing is done for many products some of which are listed below.

1) Metal Labels for all purposes.

2)

Chains and imitation jewelry (Bangles etc.)3) Gift items like toys, aluminium temples, and key chains.

4) Architectural fittings like.

a) Channels for doors, windows.

b) Light lampshades.c) Door handles.

d) Light switches and even wires.





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5) Utensils like Lunch boxes, Thermos Flasks Glasses Frying Pans Cover, Ice pails.6) Spectacles.

7) Lipstick cases.8) Parts of engines, airplanes.9) Watch dials & straps, Timepieces.

10) Fans.

11) TV Cabinets & Computer Bodies.

(The above information is given in good faith only and without any liability on our part. Customers are

advised to test out the products and satisfy themselves under practical methods).

KEVILUMINIUM GOLDEN YELLOW 4GLN

We highly recommended Keviluminium Golden 4GLN for those products requiring excellent light

fastness properties. Please note that our yellow 4GLN is very suitable for heat and we have tested the

same upto 400 degree centigrade so please follow the instruction given in the sheet.

To get the desired result kindly follow the following step.

1. Cleaning & Brightening : Kindly see that the articles have the highest purity of aluminum.

2. Anodizing: Time : 35-40 minutesCurrent Density : 14 amps /sq. ft.

Sulphuric Acid : 28.5 Tw (230gms/1 free sulphuric acid)

Temperature : 18-20 Degrees CentigradeAnodic Film Thickness = 24-30 microns

3. Rinsing and Neutralizing: Kindly rinse thoroughly with good supply of running water.

4. Dyeing:

Time : Depends on the shade required (15 secs to 15 minutes)

Concentration : Preferable to keep high at 30 gms per /litre

Temperature : 60 Degrees Centigrade.Ph : 3. 5-4

(Control by dilute caustic soda or dilute oxalic acid)

5. Sealing :

Method : a) Steam or simple boiling water b) Kevi. Sealofix N-1200 to get better results.

Time : 45-60 minutes.

Temperature : Boiling water.





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6. Precautions :

Kindly do not leave the product exposed to sunlight either in the solid form or the solution.Prepare the solution only in Plastic Barrels, Wood or stainless steel vessels and not in iron or copper

vessels.

Store solution in dark place and preferable covered.

This information has been given in good faith only and without guarantee since the steps recommended

have to be followed properly and are not in our control & adaptations to local conditions may be

required to be done by the user.

K E V I B I T

Kevibit is a fine brown bitumen powder which is very stable to acids, alkalies and salts and is used inetching and multi colour labels on anodized aluminium.

Method of application for etching articles :-

1. The aluminium plate is printed with non-drying printing ink on the portion that is not to be

etched.2. Then the piece is dipped in Kevibit untill the entire area of step(1) above is covered.

3. Remove the excess powder by cleaning with cotton waste.

4. Bake the same in an oven or fire burner to form a hard surface.

5.

Do the necessary steps for etching. We can recommend the use of Kevitech FCA and KevitechSCA , Kevitech WSA(Information available on request) used for etching.

6. After etching, to remove the bitumen baked area it should be dissolved by using hydrocarbon

solvents like Kerosene or Petrol. Thereafter you may proceed with the next step.

Method of application for Multi Colour anodizing :-

1. After the anodizing stage you should do the reverse printing of the area to be coloured by the first

colour with Non-Drying Printing ink.2. Then the piece is dipped in Kevibit until the entire area of step (1) covered.

3. Remove the excess powder by cleaning with cotton waste.

4.

Bake the same in an oven or fire burner to form a hard surface.5. Do the dyeing stage with Keviluminium colours.6. After etching, to remove the bitumen baked area it should be dissolved by using hydrocarbon

solvents like Kerosene or Petrol. Thereafter you may proceed with the next step.

Advantages of Kevibit: -

1. The powder is of a very fine nature and hence will cover the smallest area.

2. Economical since the amount of powder used will be much less than powders of a higher gauge.

3. Available in different packing for your convenience.

(INFORMATION IS GIVEN IN GOOD FAITH AND WITHOUT GUARENTEE)





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KEVITECH FCA

Etching is sometimes done on aluminium to get matt finishing and the following process can do the

same:

1) The medium should be prepared with regard to the effect that may be desired and the

depth required.

2) Preparation of medium

35% Kevitech FCA

25% Hydrochloric Acid Conc.

in water. The use of 4% Potassium Chlorate is also recommended for different mattfinishes.

3) Kindly dip the desired area in the above solution at 20°C.

4) Rinse the article under running water for 10 minutes.

5) Then prepare for anodizing.

KEVITECH SCA (SATIN) andKEVITECH WSA ( DEEP ENGRAVED EFFECT)

Etching is sometimes done on aluminium to get satin etch finishes and the following produce could

help you obtain the same.

1) The medium should be prepared depending on the depth and desired effect wanted.

2) Prepare the medium as follows :

100 Gms. Per Litre of Kevitech SCA

3) Heat the solution upto 80°C.

4) Dip the desired area into the solution for about 1 to 10 minutes depending on

the result required.

5) Rinse the article under running water for 5-10 minutes.

6) Prepare for anodizing.





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KEVIZIN PRG LIQUIDPROPERTIES

Appearance Colourless liquid with slight odour.

Chemical Character Substituted polygycol either and amino acid

Derivative in aqueous organic solution.

Density at 20

C / 68

C About 1

Ionic Character Nonionic

PH of commercial Product 11.5 – 12.5

Storage Stability Good between –20°C to +50°C.

Solubility Dilute able with cold water in any proportion.

PH application range 4-14

Stability of solution to

Hard Water Very goodAlkali, Acid, Salts Very good

Anticorrosive effect Has an anticorrosive effect against rust film

on Iron if not rinsed off.

Forming Low to medium foaming

Boiling Point About 100°C.

Flash Point No flash point upto boiling point

Toxicity Non-toxic in nature.





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A FEW IMPORTANT POINTS TO REMEMBER

In case the person testing the products finds some difficulties please advice the following to him :

1. Dissolve the dyes in hot water and then when the full powder is fully dissolved should you put

the anodized pieces else the powder will forms patches during testing. Please use distilled water or at

least soft water(not hard water containing metallic salts) to dissolve and in all dye baths used by you.

2. Use very little acetic acid (to control ph only) only if the colours do not adhere on the aluminium.

Normally dyeing is done at 65° to get fastness to water and light and at room temp in case of multicolor.

In case of deep blacks keep the ph at 4.5 to 5.00 to get best results.

3. Dip for at least 3 minutes for gold’s 5 minute for other colours and 15 minutes foe black to get the shade

you want so that it will pass the rigorous tests you want. Dilute the colour but please dip for min.5 minutes

of time for the color to penetrate properly.

4. Rinse with running cold water to remove the excess colour.

5. Please do the sealing of the piece with our sealing chemicals and allow drying for minimum 1 hour before

further tests are carried out. This helps in seeing that the chemicals penetrate properly into the aluminum.

Use ZAB first and then N-1200(Contains Lead Compounds)

Your inputs of the etching, brightening, anodizing, coloring, sealing method adopted by your organization will

be a valuable source of data to help us in understanding your organization’s needs and accordingly we may

suggest the chemicals and colors best suited to you out of the entire rang which we produce. Your input helps

in saving valuable time & energy and will helps us in starting the business faster.

Your test reports positive or negative will be highly appreciated and this will strengthen the understanding for both organizations to improve the qualities to be the best.

Regards,

For Khatau Valabhdas & Co.,

Harsh Khatau

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