In contrast with the conventional UV/Ozone method, we distinguish and tentatively call "UV Sensitizing Method", or the UV surface processing with the combined use of photo sensitizer.
The effect of enhancement in adhesion power varies depending upon the type of adhesion.
There was no significant difference in results between the UV sensitizing method and the UV/Ozone method for thecase of copper foil adhesion.
In case of electroless plating and sputtering copper adhesion, on the contrary, there was five times or more difference.
In case of resin mold sealing adhesion, the UV sensitizing method was at 1.8 times higher. than the UV/Ozone method.
Regarding the capacity of the UV sensitizing process and plasma treatment, there was no such difference as generally considered.
It proved to be almost the same. There are various types of film-carrying system developed and available including Single sheet feed (Fig.6) and Roller conveyance (Fig. 7).


Fig 7. Single sheet feed type UV sensitizing film processor.	Fig 8. Role to role roller conveyer type UV/Ozone film processor. continued to p6

The UV surface modification technology is useful in the production of not only high-tech products but also general industrial products. Shown for example is UV/Ozone Pre-adhesion Processor for the plastic aquariums which are regarded as low-tech products (Fig. 9).

Fig 9. UV/Ozone Pre-adhesion Processor for the plastic aquariums.

The Processor saved the conventional primer coating, improved working environments and promoted a mass production system.
The flat plates and frames of reinforced polystyrene are adhered with a silicone sealant.
Fig. 10 shows variations of adhesion strength when reinforced polystyrene plates are treated by the UV/Ozone process.
As it have described in Fig. 5 and Fig. 6, it is apparent that the adherend has something to do with the adhesive in terms of the optimum surface energy.
The unit shown in Fig. 9 was developed in reference to the results of this preliminary test.

Fig 10. Relationship between the strength of
the adhesive strength and UV exposure

The author mentioned before that metals can also be modified, but unlike the mechanism of polymer, minute oxidized film is formed on the surface, which is regarded to work for enhancement of adhesion.
It is proven that when the UV/Ozone process is applied to gold, it imparts cleaning effects in the beginning and then oxidizing reactions.
After processing for one hour, Au2O3 of about 17Å was formed bringing more surface energy and a higher hydrophilic property.
When we continued the process, re-pollution occurred due to the sulfur oxides in the atmosphere.
In case of cleaning, you are suggested to work in clean air.

Table 3.Comparison of the cleaning powers among the various cleaning methods

Cleaning conditions	Contact angle (degree)
Non-treated glass plate	26
Synthetic detergent(US) Water(US) Hydrocarbon solvent(US)(Vap)	39
Synthetic detergent(US) Water(US) Pure water(US) Dry(70ºC)	17
Synthetic detergent(US) Water(US) IPA(Vap)	13
Ozone solution	<10
Synthetic detergent(US) Water(US)Plasma	5
Synthetic detergent(US) Water(US)UV/O₃	4

Note 1, Plasma: 200W, 1torr, 5sec, 13.56MHz
Note 2, UV/O₃:Low pressure mercury lamp , Atmosphere, 60sec
Note 3, (US): Ultra sonic (Vap): Steam washing (70ºC): Air dry

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