Aquadine, a water-soluble table adhesive, is an acrylic copolymer with excellent adhesive strength that can be used effectively in the fixing of any type of substrate. It is especially effective in the fixing of fabrics of synthetic fibers that are difficult to fix with starch, gums and PVA and in the fixing of special weaves of natural fibers that do not adhere well.

1. Series

1) 100 Series

The 100 Series are table adhesives of sodium salt of acrylic ester copolymer with strong adhesive properties. They are suitable for use with any synthetic fibers excluding acryl.
The 100 Series consists of the following items:

2) 200 Series (patent pending)

The 200 Series products consist of a special polymer. They are water-soluble table adhesives with good acid resistance. Adhesives of the 200 Series will not solidify even when they come into contact with strongly acidic printing pastes. Since they preserve their water solubility, they are suitable in the fixing of acryl fibers that are dyed with cationic dyestuffs. They are, of course, also suitable for use with other fibers. Products of the 200 Series are the most suitable for use with the topping method used in conjunction with permanent table adhesives.

200 Series consists of the following:

3) 500 Series

Aquadine 501 is a table adhesive consisting mainly of modified PVA.
Aquadine 501 can be used in the fixing of woven cloth of spun yarn like cotton and cotton/polyester.
The Aquadine 500 Series consists of the following:

2. Important points in fabric setting with Aquadine

Water-soluble table-adhesives are mainly used with auto-screens and rotary machines.
Attention must be paid to the following two points when using Aquadine.

1. The viscosity and the concentration of the table adhesive when it is used.
   
2. Its condition after the drying that occurs between application and fabric setting.

If the viscosity of the table adhesive is too high, too much may be applied, and if it is too low, too little may be applied. The viscosity is in general proportional to the concentration, so if the viscosity is too high, dilute it with methanol or water. In general, if it is not applied above a certain concentration, the adhesive strength will be less than ideal. Drying between the application of the adhesive and the fixing of a substrate is very important. If drying is not maintained at a suitable level (50-70%), the coating will not be effective in fabric setting. If the machine is fast or the concentration too low, the adhesive strength will be weak due to insufficient drying. While dilution with methanol improves drying, this can be expensive and a room full of methanol vapor is quite dangerous. To accelerate drying, dilute the adhesive with water and use drying equipment.

Topping method

The topping method involves applying the water-soluble table adhesive Aquadine 200 Series (called the topcoat) as required to a belt that has previously had applied to it a matching type of Newdine permanent table adhesive (called the undercoat). This improves the effectiveness of the fixing through a multiplier effect and improves workability. This technique is one that has been developed by our company.

The use of the topping method is convenient and economical in the following cases:

1) Printing cotton and cotton/polyester with reactive dyestuffs

Water-soluble table adhesives diluted to 20~100% are usually used in the printing of cotton and cotton/polyester. While water-soluble table adhesives are convenient, they are extremely costly and can produce waste water with harmful contaminants.

In the topping method, Newdine A Series, which can be used alone, is applied as the undercoat. Aquadine 200 Series diluted in 2~6 times as much water is used as the top coat when a permeable fabric with ground printing or large pattern is to be printed and a strong alkali is to come into contact with the table adhesive or when a pigment is used. The resulting coating consists of a durable undercoat covered by a topcoat. Since the topcoat can be diluted according to requirements, this method greatly enhances the fixing process in relation to cost and to waste water regulations and by eliminating the fixing stage.

2) When chemicals such as pigment, white pigment and cationic dyestuff or items with pronounced dye staining are used temporarily, the method used is the same as that in 1).

Aquadine 200 Series must be used as the diluted table adhesive for the topcoat. If any other diluted table adhesive is used, it will violate the surface of the permanent table adhesive used as the undercoat, severely reducing its durability, damaging its surface, and thus reducing the effectiveness of fixing.

Permanent table adhesives are usually used alone in fixing for printing with disperse and acid dyestuffs.

Application to the printing table

1. Preparation of the printing table

Materials commonly used in the construction of printing tables include wood veneer, felt, steel, and asbestos. If Newdine is directly applied to the surface of a printing table made from anything other than steel, it will penetrate without forming the film that provides the flat and smooth surface for fixing. Furthermore, a film of Newdine will peel off some materials. To avoid these problems, preparation appropriate to the material used is necessary. This preparation is required only once for each table.

1) Wood veneer

There are three ways to prepare a wood veneer table:

1. Putty coating
2. Polyester film laminating
3. Rubber sheeting

a. Putty coating

This method involves applying Repair Putty H or M (polyester resin produced by Yokohama Polymer) to the surface of the printing table in order to reinforce it. This will produce a smooth, flat, water resistant surface suitable for the application of Newdine. However, since the coating only has a certain lifespan and is unstable, the complex application process is best left to specialists.

Putty is first applied evenly to the surface of the printing table. After it has dried, it should be polished with sandpaper to improve its affinity for Newdine.

b. Polyester film laminating

Polyester film

Applying a polyester film
Method 1

1. Draw a line that bisects the table. Spread the polyester film from one end of the printing table to the other, cutting it so that there is an overhang of 5cm at both ends. In the center of the film draw a line that matches the line on the table. This line is the center line of the film.
   
2. With the two center lines lined up, evenly roll in both ends of the film.
   
3. For the adhesive between the film and the table, use Newdine T/GT mixed to a ratio of 1:1, or, if using a product outside the T Series, anything mixed so as to have strong adhesive force. Apply directly to the table with a squeegee.
   
4. With the center lines of the table and the film lined up, slowly unroll both ends of the film while use a rolling pin to remove air from under the film.
   
5. If the table has a heating unit, raising the temperature during this operation will prevent air from collecting under the film.
   
6. After the film has been totally unrolled and set on the table, lightly polish that part of the film within the working width with sandpaper.
   

Fig. 5

Method 2

1. Apply a strong blend containing Newdine to the table with a squeegee.
   
2. Place PVC pipes (2~3cm diameter) on the table lined up at 5~6cm intervals.
   
3. Cut polyethylene film to the length of the table. Stretch it over both ends of the table and fasten it.
   
4. With the film pulled over both ends, remove the pipes one by one, and press down the film, removing air with a rolling pin.
   
5. Repeat until the last pipe is removed and the film is firmly affixed to the table.
   
6. After the film has been fully unrolled and set on the table, lightly polish that part of the film within the working width with sandpaper.

Fig. 6

Points to remember

1. The surface of the printing table to which the polyester film is to be pasted must be flat.
   
2. Never use any kind of cushion. Insertion of any type of cushioning layer between the table and the film will prevent the film from adhering to the table. This may result in film peeling off or moving during printing operations.
   
3. Use Newdine at a mixing ratio that produces very strong adhesion as the adhesive between the film and the table.
   
4. To prevent air from gathering under the film, press air out while the film is still being unrolled. Removing air after the film has completely set is very difficult.
   
5. To improve its affinity for Newdine, the surface of the film should be polished with sandpaper.
   
6. A squeegee with the rubber removed can be used as a roller.
   
7. If a small amount of air between the film and the table is difficult to remove, use a hypodermic syringe to extract it.
   

c. Rubber sheeting

This method involves covering the wooden surface of the printing table with a rubber sheet to act as a cushion. Rubber sheeting is stuck down with adhesive and Newdine is applied to its surface. Recently, rubber sheeting has been placed over heating elements installed onto existing wooden-topped printing tables. This modification produces a heated table capable of maintaining a temperature in the range 30~80. Advantages of this method include:

1. Existing tables can be changed into heated tables.
2. The temperature rises very quickly during heating. Even in winter, the table can be heated to 80 in under 5 minutes.
3. The target temperature can be set easily, and the temperature setting can be changed readily.
4. The dispersion of heat on the surface is extremely even, any heat differences being in the range ±1.
5. Heating and lighting costs are reduced.

Steel plate is used in the construction of printing tables when drying is to be conducted thoroughly. Steam pipes of a special heating element are installed on the reverse side of the steel plate and printing is carried out with the temperature maintained in the range of 30~80. Although the set-up costs are high, steel plate has come to be very commonly used today because of the high efficiency and the very sharp printing that result.

If Newdine is applied directly to the printing table, the film will eventually peel off because of its low affinity for the metal. Thus, an intermediary should be applied as a primary coating. This intermediary can be either putty or polyester film laminate.

a. Putty coating

To ensure that the surface of the metal plate is free from oil and other impurities, it should be cleaned with a chlorine-based solvent such as trichlene. Since putty will peel off from locations in which impurities remain, it is very important that the surface is cleaned carefully.

After this, Repair Putty (manufactured by our company) is applied with a squeegee. When the putty has hardened, it should be polished to produce a smooth flat surface. Please consult a firm specializing in this process.

After putty has been applied to the required locations, an anti-rust compound agent should be applied anywhere putty has not to prevent rust.

Newdine can be applied to the table after the procedure outlined above has been completed.

b. Laminating

After thorough cleaning, Newdine with strong adhesion is applied directly to the surface of the metal plate. Polyester film is set over this as outlined previously.

2. Applying Newdine

Before the application of Newdine to the printing table, impurities such as paste, oil or dirt should be removed, along with any water. If too much Newdine is applied at one time, while the surface of the Newdine may form a film, solvent will still remain beneath it. If this is the case, Newdine will adhere to the reverse side of the substrate during printing, which will result in resin lifting off the table. Thus, Newdine should be applied thinly a number of times to ensure that the application is successful.

Fig.7

The equipment required includes, as shown in Fig. 7, A: some form of container for pouring the Newdine, B: a squeegee slightly longer than the width of the printing table, and C: a tin or stainless steel catch pan. The application process requires three or four people. The catch pan is placed on the rail of the printing table and the squeegee is placed above. Previously prepared Newdine is then placed in the pouring container. One person pours Newdine along the top of the inclined table. 30cm behind that the squeegee is advanced in the direction of the arrow by two operators, one at each end. Run-off Newdine is collected at the bottom in the catch pan. After a coating has been applied to a table, Newdine in the catch pan can be returned to the pouring container. For the first coating of Newdine, one printing table measuring 1.20m x 25m, for example, should be coated with 2~3kg of Newdine over 6 to 8 separate applications.

Fig.8

3. Removing Newdine

Newdine can be removed by an organic solvent, but if the organic solvent is simply used in its original state, over 50% will evaporate and not play any role in the actual removal of the Newdine. Not only is this very wasteful, it can also be very dangerous due to the risk of fire and inhalation of solvent vapor. In addition, it is recommended that the resin solution which is removed is not simply allowed to flow away as this can cause the blockage of drains. We recommend removing Newdine by dissolving it in water.

Since most printing tables are inclined, any solvent or removing agent spread on the table will run off. Thus, to remove Newdine:

1. Cover the printing table with an old cloth around 5m long.
2. Apply the removing agent so that it will be soaked up by the old cloth. (The type of removing agent varies according to the Series of Newdine used).
3. Leave for 2-3 minutes.
4. Remove the cloth from the printing table.
5. Wash away the Newdine by pouring water on that part of the table to which the cloth had been applied.
6. Move the cloth to the next area to be cleaned and repeat the above operations.

There are three types of remover available for use with Newdine:

1) Removers for T, K and J Series

1. Remover FK can be used by itself or in a mixture with 1 in 3 parts trichlene or trichloroethane
   
2. Remover CL can be used in a mixture with an equal amount of trichlene or trichloroethane

Note:
Remover FK is relatively safe because its flash point of +10 is about the same as that of methanol, but if required the risk can be dramatically reduced by mixing it with 1 in 2 or 3 parts trichlene or trichloroethane.