C.ANIRUTHAB.TECH TEXTILE TECHNOLOGY

KUMARAGURU COLLEGE OF TECHNOLOGY.

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INDEX

S.NO CONTENTS PG NO.

1. NEED FOR PLASMA TREATMENT 8

2. PLASMA APPLICATIONS TO FIBRES 10

3. PLASMA SPRAYING TECHNIQUE 12

4. ADVANTAGES OF PLASMA TECHNOLOGIES 14

5. PROPERTIES OF PLASMA DEPOSITED FIBRES 15

6. ECONOMICAL AND ECOLOGICAL ASPECTS 15

7. ADHESION IMPROVEMENTS 15

8. INFLUENCE OF PLASMAS 16

9. PLASMA TREATMENT OF WOOL TO ACHIEVE

SHRINK RESISTANCE

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10. TYPE OF PLASMA TREATMENT 19

11. VACUUM SURFACE TREATMENT EQUIPMENT 20

12. PLASMA SURFACE MODIFICATION 23

13. PLASMA TREATMENT OF SYNTHETIC FIBRES 24

14. BARRIER COATINGS 28

15. APPLICATIONS 29

16. CONCLUSION 30

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Use of plasma

technology in textiles

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USE OF PLASMA TECHNOLOGY IN TEXTILES

Plasma is an ionized form of gas and can be created using a controlled level of AC or DC

power and an ionizing gas medium. It is an ensemble of randomly moving, charged atomic

particles with a sufficient particle density to remain, on average, electrically neutral. Plasmas

are used in very diverse applications, ranging from manufacturing integrated circuits used in

the microelectronics industry through treating polymer films to the destruction of toxic waste.

Plasma processes can be grouped into two main classes — low-density and high-density —

according to their electron temperature versus electron density. In low-density, direct-current

and radio-frequency glow discharges, the electron and heavy particle temperatures are not

equal. Low-density plasmas have hot electrons with cold ions and neutrals. Energetic

electrons collide with, dissociate and ionize low-temperature neutrals, creating highly

reactive free radicals and ions. These reactive species enable many chemical processes to

occur with low-temperature feed stock and substrates.

Well-known types of plasmas encountered in surface treatment processing techniques

typically are formed by partially ionizing a gas at a pressure well below that of the

atmosphere. For the most part, these plasmas are weakly ionized, with an ionization fraction

of 10-5 to 10-1. Electron cyclotron resonance (ECR) plasmas can have higher ionization at

high power. Because these systems are run at low pressures, vacuum chambers and pumps

are needed to create and contain these plasma processes.

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The atmospheric plasma system allows creation of uniform and homogenous high-density

plasma at atmospheric pressure and at low temperatures using a broad range of inert and

reactive gases. The atmospheric plasma treatment process (ATP) treats and functionalizes

material surfaces in the same way as the vacuum plasma treatment process on a wide range of

materials; and has unique advantages over the presently used corona, flame and priming

treatment technologies. APT production equipment testing has been successfully performed

for the treatment of various materials, including PP fiber, PP and polyethylene (PE)

nonwovens, polyester fiber, Tyvek®, nylon, wool, textile yarn, oriented PP film, PE film, PE

teraphthalate (PET) film and polytetrafluoroethylene film. The surface energies of the treated

materials increased substantially (without any backside treatment), thereby enhancing their

wettability, printability and adhesion properties.

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Plasma treatment has an explosive increase in interest and use in industrial Applications as

for example in medical, biomedical, automobile, electronics, semiconductor and textile

industry. A lot of intensive basic research has been performed in the last years, also in the

field of textiles and technical textiles. This has resulted in an increasing knowledge of the

possibilities of this process regarding demands as wet ability, shrinkage resistance of wool,

dye ability, printability, coating and wash ability of conventional and technical textile. All

day problems of wet ability and adhesion, together with the environmental driven forces have

increased the interest of industry today. A fundamental problem at this moment for the

implementation of this technique at a higher level is the lack of adapted machines.

The plasma technology is considered to be very interesting future oriented process owing to

its environmental acceptability and wide range of applications. Plasma treatments have been

used to induce both surface modifications and bulk property enhancements of textile

materials, resulting in improvements to textile products ranging from conventional fabrics to

advanced composites. These treatments have been shown to enhance dyeing rates of

polymers, improve color fastness and wash resistance of fabrics, and change the surface

energy of fibers and fabrics. Research has shown that improvements in toughness, tenacity,

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and shrink resistance can be achieved by subjecting various thermoplastic fibers to a plasma

atmosphere. Recently, plasma treatments have been investigated for producing

hydroscopicity in fibers, altered degradation rates of biomedical materials (such as sutures),

and for the deposition of anti wear coatings.

Need For Plasma Treatment

Textile manufacturers and end-users alike have been searching for ways to improve the

surface properties of natural and man-made fibers. Specifically, there is a need to improve

adhesion, wettability, printability and dye ability; as well as to reduce material shrinkage.

Methods of modifying fiber properties to make polypropylene (PP) dye able, including the

process of copolymerization with polymers that can be dyed, have been evaluated.

Traditional latex systems and primers with low melt points have been used to coat fabrics to

promote ink adhesion, heat-sealing and thermoforming performance. PP nonwovens have

especially been the focus of research to enhance colorfastness properties for the material

because of its excellent chemical resistance, high melting point, low cost and adaptability to

many fabrication methods. To date, the poor dye ability of PP has limited optimization of its

applications in the manufacturing of yarns and knit fabrics, upholstery fabrics and industrial

fabrics.

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Fibers with polar functional groups can be dyed more easily than nonpolar fibers because

polar groups will chemically bond with dye molecules. Because the molecular chains of PP

are nonpolar and its surface is hydrophobic, the dye molecules will not bond chemically to

the fibers. PP fiber is highly crystalline as well, which also restricts its dye ability.

Functional groups may be introduced onto the fiber surface by using gas plasma treatments,

improving fiber surface properties without affecting the fiber’s bulk properties. By creating

a polar layer on the fiber surface, in reaction with functionality introduced, wettability of the

fiber for dyeing is enhanced with hydrophilicity.

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Plasma Application to Fibers

Parallel plate reactor for plasma polymerization

1 = vacuum chamber; 2 = electrodes; 3 = substrate;

4 = plasma; 5 = exhaust gas cleaner; 6 = vacuum pump;

7 = high frequency generator; 8 = gas supply (CH4).

The high-frequency electromagnetic transmitter which is often used for the generation

of a technical plasma, primarily give their energy up to the electrons, because these are

significantly less inactive that the ions. This means that the electrons are "heated" and

thus their average kinetic energy, i.e. their temperature, increases. Collisions between

electrons and ions cause electrons to pass their energy on to the ions. Due to the great

mass difference this energy transfer is only small. A number of collisions are necessary

to achieve a balance between ion and electron temperatures. The number of collisions

which a particle undergoes depends upon the pressure. At a high pressure the number of

collisions is high, and there is a rapid equalization of the average energy of electrons

and ions. In low density plasmas, on the other hand, this thermalisation between the

particle types is not effective, and a system is created made up of hot electrons and cold

ions.

In addition to thermal equalization, collisions also play a role in the maintenance of the

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charge carriers. A mixture of electrons and ions will tend to form neutral atoms by the

combination of the two particles. This process is known as recombination. This

recombination leads to the two free charge carriers (electrons and ions) becoming a

neutral atom, thus causing the plasma to lose some of its conductivity. Recombination

is the process that converts an ionized gas into a "normal" gas. The stable burning of

ignited plasma requires equilibrium between the destruction and generation of charged

particles. This source consists of the above. Mentioned collisions between electrons and

atoms or ions. If a hot electron hits an atom, it can knock out a captive electron

(ionization). Whereas originally there was one free charge carrier, after the collision

there are three. If equilibrium exists between recombination and ionization, then the

plasma will burn in a stable manner. However, the ionization of an atom is not the only

process that can be triggered by an electron collision. [n order for an electron to ionize

an atom, it must transfer minimum energy to the atom during the impact, the ionization

energy. If energy transfer due to the impact is less than the ionization energy, then the

struck atom is excited. The excited states are usually not stable, and such an atom

returns to its original state, the basic state, radiating light as it does so. This is the cause

of the illuminated appearance of plasmas.

Plasma Spraying Technique

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In plasma spraying, the surface being coated is sprayed with droplets in the same way as

color spraying. In contrast to color spraying, the film material in plasma spraying is not

liquid, and must first be melted by a high-energy heat source and then sprayed onto the

cold surface of the fabric or three-dimensional body. When the droplets hit the surface they

are flattened and cool off instantaneously due to heat transfer to the base material

(substrate). The particles solidify and shrink. The films adhere primarily due to mechanical

adhesion and locally due to chemical bonding forces of different types. In order to achieve

a strong film adhesion, the cleaned surfaces are roughened by sandblasting. This gives

good adhesion, because the particles penetrate into the surface roughness and shrink onto

the peaks.

The heat source used in plasma spraying is an electric arc in a nozzle, which heats up a

flow of gas (usually argon, nitrogen or helium) to very high temperatures. Gas

temperatures in excess of 20000°C occur, which lead to the splitting of molecular gases

and the partial ionization of atoms. As a result Of the high temperatures a marked increase

in the volume of the gas (plasma) takes place, which flows out of the nozzle at high speed,

in plasma spraying plants the flow speed of the plasma jet reaches several times the speed

of sound. The powdered film material is injected into this high. Energy plasma jet with the

aid of a carrier gas. The particles themselves are melted and blasted onto the pretreated

base material. The particle speed itself, however, is below the speed of sound. Almost all

materials which melt without decomposing and can be manufactured in a suitable grain

size can be processed into high quality coatings by plasma spraying. Normal plasma spray

coatings are generally chromium oxide coatings or aluminum oxide coatings. However,

tungsten carbide cobalt coatings and pure tungsten coatings can also be applied by plasma

spraying.

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Plasma Spray

Gas Plasma Technology For Textile & Filtration Applications

Activation, hydrophilic, hydrophobic or other surface modifications are part of the

possibilities gas plasma technology can offer to film & textile manufacturers and can be

performed on real production scale.

We have a demo-unit available to evaluate on real scale how plasma technology can suit

your specific surface treatment or modification needs.

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Advantages of plasma technologies and properties of plasma produced

films

1. Technological aspects of plasma treatment

Final cleaning, activation and coating in a single technological step.

Three dimensional substrates can also be coated.

2. Chemical aspects of plasma treatment

Chemical diversity of film forming substance.

No polymerization aids necessary.

High cross linking.

Possible to produce special functional groups on the surface.

E.g.: hydroxyl

Amine

Aldehyde

Carboxyl

Grafting of larger molecules.

Properties of Plasma Deposited Films

* Good adhesion can be achieved.

* High homogeneity of film thickness and structure.

* Surface and film properties can be varied in a wide range.

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Economical and Ecological Aspects of Plasma Treatment

Low costs for raw materials and low running costs.

Low consumption of chemicals.

Solvents free, dry process.

The used chemicals are kept in closed equipment.

Adhesion improvement by plasma treatment

Adhesion between the substrate and the material applied onto it plays a critical role for

adhesive bonding, printing and for coatings such as varnish, metallization, etc. In this case, a

number of mechanisms and factors may be responsible for the adhesion, such as the wetting

of the substrate, its morphology, polarity, formation of chemical links between the substrate

and coating, etc. Minimal contamination on the surface as well as the formation of a so-called

weak boundary layer can drastically reduce the adhesion levels.

Numerous methods are used, depending on the "contact partners", to achieve good adhesion,

including treatments with solvent based and aqueous solutions, flame treatment and corona

treatment. However, these are also subject to numerous restrictions and disadvantages, such

as material consumption and environmental contamination in the case of wet treatments, or

reproducibility problems in the case of flame treatment or corona. Pretreatment of products

before adhesive bonding or coating may take several hours.

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Plasmas influence a number of surface characteristics which are critical for

good adhesion:

The surface can be cleaned and

Roughened

It is made polar and thus wettable

The sub-surface material is cross-linked, increasing its mechanical and chemical

stability and the surface can be provided with chemical functional groups resulting in

to a chemical interaction (e. g. by reactions with the functions of the adhesive)

between the substrate and the coating or the adhesive.

Treatment of Cotton with Different Kinds of Plasma Gases

The specific surface area of cotton after oxygen plasma treatment is increased. On the other

hand, the treatment with hexamethyldisiloxane (HMDSO) plasma leads to a smooth surface

with increased contact angle of water (sessile drop method) up to a maximum of 130°. Thus,

a strong effect of Hydrophobisation is achieved. Similarly, when hexafluoroethane plasma is

used instead of HMDSO plasma the surface composition of the fibers clearly indicates the

presence of fluorine and the material becomes highly hydrophobic. Still, the water vapor

transmission is not influenced by the Hydrophobisation. Hydrophobisation in conjunction

with increased specific surface area results in an effect generally known as Lotus effect: dirt

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particles are easily removed from the surface by water droplets. If intensive oxygen plasma

treatments are applied to cotton fabric also negative effects can be observed namely a reduced

tear and abrasion resistance. The negative impact can be minimized by appropriate treatment

conditions.

Advantages of plasma processes

Low consumption of chemicals

Little environmental contamination

Short treatment times

Otherwise problematic substrates (for example perfluoropolymers) can be made capable of

adhesive bonding/coating with good adhesion

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Plasma Treatment of Wool to Achieve Shrink-Resistance

The morphology of wool is highly complex; this is not confined to the fiber stem but

extends to the surface as well. Cuticle cells are overlapping each other to create a

directional frictional coefficient. Moreover, the very surface is highly hydrophobic. As a

consequence, in aqueous medium, because of the hydrophobic effect, fibers aggregate and,

under mechanical action, exclusively move to their root end. This is the reason for felting

and shrinkage. Plasma treatment of wool has a two-fold effect on surface. First, the

hydrophobic lipid layer on the very surface is oxidized and partially removed; this applies

both to the adhering external lipids as well as to the covalently bound 18-methyl-

eicosanoic acid Since the exocuticle, that is, the layer below the fatty acid layer of the very

surface (epicuticle), is highly cross-linked via disulfide bridges plasma treatment has a

strong effect on oxidizing the disulfide bonds and reducing the cross-link density. As the

plasma treatment is surface-oriented the protein loss after treatment and extraction is very

low (0.05 % o.w.f. for severe treatment). On the other hand, the specific surface area is

significantly increased during plasma treatment from about 0.1 m 2 /g to ca. 0.35 m 2 /g,

which is clearly demonstrated by means of atomic force microscopy. Again, due to the

surface-directed activity of the plasma, the tenacity of the fibers is hardly influenced. As

the surface is oxidized, the hydrophobic character is changed to become increasingly

hydrophilic. The chemical and physical surface modification results in decreased shrinkage

behavior of wool top; the felting density of wool top (before spinning) decreases from

more than 0.2 g/cm to less than 0.1 g/cm.

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Types of plasma treatment

Plasma changes the surface in many respects, although not all of these changes have a

positive effect on adhesion: in fact, a plasma treatment can also contribute to the creation of

weak boundary layers. The correct choice of the parameters (type of gas, power, treatment

duration, etc.) is thus critical. It is also very important to be able to characterize the surface

changes resulting from the treatment.

The best known for adhesion improvement on polymer surfaces is the use of argon, oxygen

and air plasma. With the parameters chosen correctly, this approach is often successful.

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However, these apparently simple plasmas lead to very complicated chemical actions on the

surface (particularly if subsequent contact with air is involved). These relatively aggressive

plasmas frequently destroy or weaken the sensitive substrate surface. The reactions initiated

by the plasma may continue during storage, and may adversely affect the reproducibility.

Therefore, we mainly use custom tailored plasma systems, which lead to a defined surface

and to substantially reduced extent of secondary reactions. These belong to one of the

following two classes: functionalizing or depositing plasmas.

The type of plasma treatment must be selected and developed for each specific case under

consideration of the goods to be treated, the treatment location within the technological chain,

and financial viability.

Vacuum surface treatment equipment

We possess various equipment for implementation and development of different plasma-

chemical and -physical processes in low to sub-atmosphere pressure (approx. 0.01 to 300

mbar) plasmas. These setups include both commercially available (partly modified) and

home-built systems. We are in a position to quickly build a suitable laboratory or pilot-scale

reactor for special sample geometries and process requirements and equip it with the

components available in the Institute (process gas flow and pressure controllers, vacuum

components, RF generators etc.).

Plasma Excitation

frequency:

o low (kHz to 100 kHz range)

o radio frequency (13.56 MHz)

o tunable 0-50 MHz

o microwave (2.45 GHz)

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power:

o from a few W up to ca. 1 kW

o Specific powers up to ca. 8 W/cm2.

Process gases

inert gases

reactive gases for surface modification (e. g. oxygen, hydrogen, halogen containing

gases)

Depositing gases (e. g. silanes/siloxanes, alkanes/alkenes,

fluoroalkanes/fluoroalkenes, acrylic or amine compounds).

  Setups

installation for continuous plasma treatment of webs (web up to 18 cm width)

setup with plasma diagnostics

parallel plate reactors

o sample size up to 29x39 cm (patented construction)

o cylindrical reactors, diameter 20 and 30 cm

tube reactor for modelling experiments on small samples

setups for PVD

parylene coating apparatus

And more.

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Improvement of copper adhesion on polyimide films

The initial situation

Polyimide / PI (e. g. Kapton ®) is an advantageous substrate material for flexible printed

boards, ribbon cables and multilayer PCBs because it combines mechanical strength,

temperature and chemical stability with good dielectric properties. For these reasons, PI has

become increasingly widely used in recent years, especially in miniature devices such as

mobile phones, in automobile electronics, aerospace electronics etc.

High demands are placed on the reliability of PCBs used in these applications, many of them

being safety related. In particular, the copper conductors must adhere firmly to the polyimide

to withstand the thermoshock from the soldering during the PCB assembly as well as the

stresses from the vibrations, shocks, and temperature and humidity fluctuations during the

device exploitation.

Currently, copper-polyimide laminates are made almost exclusively by adhesive bonding.

The tendency towards using ever thinner PCBs means however that the adhesive makes up an

ever higher proportion of the overall mass of the PCBs, which results in worsening of the

electrical and mechanical properties of the system. Other methods of manufacturing copper-

polyimide laminates are therefore becoming increasingly interesting.

One technology that is particularly suitable for making thin laminates is the vacuum

deposition (PVD) of a thin (a few hundred nm) copper layer, followed by galvanic

reinforcement. Using a semi-additive method, only the conductors are galvanic ally

reinforced, leading to both economic and technical advantages (improved resolution).

Previously, sufficient adhesion could only be achieved by using a chromium PVD

intermediate layer. This technology was not widely accepted by the industry, as the

chromium layer requires an additional etching process during the PCB production.

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Plasma Surface Modification in Bio-Medical Applications

New medical products, materials and surgical procedures keep improving current health-care

practices. Many of these innovations involve polymeric devices that must meet certain

clinical and cost requirements. Chief among these pressures is the need for biocompatibility

between the physiological environment and the biomaterial surface. Plasma surface

modification can improve biocompatibility and bio functionality.

This article reviews the capabilities and applications of the technology. Engineered

Biocompatibility The use of synthetic materials in biomedical applications has increased

dramatically during the past few decades. Although most synthetic biomaterials have the

physical properties that meet Surface Modification Methods or even exceed those of natural

tissue, they often result in a number of adverse physiological reactions such as thrombosis

formation, inflammation and infection. Modifying the surface of a material can improve its

biocompatibility without changing its bulk properties. Several methodologies have been

considered and developed for alter the interactions of biomaterials with their biological

environments; plasma surface modification is one of these methodologies. The Process In the

plasma surface modification process, glow discharge plasma is created by evacuating a

vessel, usually quartz because of its inertness, and then refilling it with a low-pressure gas.

The gas is then energized using techniques such as radiofrequency energy, microwaves,

alternating current of direct current. The energetic species in gas plasma include ions,

electrons, radicals, Meta stables, and photons in the short-wave ultraviolet (UV) range.

Surfaces in contact with gas plasmas are bombarded by these energetic species and their

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energy is transferred from the plasma to the solid. These energy transfers are dissipated

within the solid by a variety of chemical and physical processes as schematically to result in

the surface modification.

Plasma Treatment of Synthetic Fibers

PP is a very interesting material for plasma treatment. PP is a very hydrophobic Material

with extreme low surface tension. On the other hand PP is used in a large number of

technical applications were an improved wet ability or adhesion properties are

advantageous. This is also the case for PP technical textile applications such as filters,

medical or hygiene applications, Using an oxidative plasma important improvements in

surface tension can be obtained within a very short plasma treatment. In order to obtain an

optimization of the plasma effects, a systematic approach (factorial experimental design)

was followed for the evaluation of the plasma parameters upon the obtained effects PP

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non-woven filter webs were used as test samples. Parameters varied were: treatment time,

vacuum level, treatment power. In addition some tests were performed with an adapted gas

composition instead of using O2. The obtained effects were somewhat surprising. As

expected we could observe for all plasma treatments an increase in surface tension.

However the increase in surface tension is not in correlation with the intensity of the

plasma treatments. We expected an increase in the improvement in the wet ability

properties the higher the plasma power and the treatment time is and the lower the vacuum

pressure. Once an optimum level is reached we expected the wet ability would become

constant and independent from the treatment intensity. The results showed that an increase

in wet ability can indeed be observed but only at relatively low treatment intensities. Once

the optimum is reached a sharp drop in wet ability is obtained if the plasma treatment

intensity is raised further.

Most trials were performed with O2 as plasma gas, since it was thought this gas would

offer the best results for an oxidative treatment in order to obtain wet ability. Some

additional tests were performed using air or argon/O2 blends as plasma gas.

The results indicated that often air or a blend of gases with a lowered amount of O2 offer a

better wet ability to the treated PP material. This effect can also be linked to the previous

observations. Plasma treatment with pure O2 seems to be so aggressive that very easily an

“over-treatment” is obtained reducing again the wanted hydrophilic effects. Treatment

with air as plasma gas might reduce the Aggressiveness of the treatment and as a

consequence the plasma parameters become less critical.

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When polyethyleneterephthalate (PET) fibers are used as an enforcing material for a

polyethylene (PE) matrix, the Hydrophobisation of the PET fibers using ethylene plasma is

quite impressive since the adhesion strength can be increased from 1 to 2.5 N/mm. The

fracture morphology of these composite materials clearly shows the tight adhesion of the

matrix to the fiber. Permanent hydrophilisation of PP by plasma-induced grafting of MAH.

Fracture morphology of PET/PE-composites prepared from untreated and C2H4 -plasma-

treated PET-fibers after application of the 180° peeling test.

Polyaramide fibers such as Nomex fibers are considered to be high-performance fibers;

unfortunately, they are prone to hydrolysis. Thus, the application of a diffusion barrier to the

surface should reduce the tendency to hydrolyze in respective media.

Hexafluoroethane/hydrogen plasma is highly suitable to apply such a diffusion-barrier layer

to the surface. The resistance to 85 % H2SO4 (20 h at room temperature) leaves the fibers

completely intact while conventional fluorocarbon finishing under the given conditions

produces significant shrinkage of the fibers in combination with loss of properties

The procedure

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In order to realize this vision, three Fraunhofer Institutes have pooled their

competences. These are IGB (plasma-chemical processes, analytics), IPA (vacuum

deposition of copper) and IZM (galvanic reinforcement, adhesion tests, and

analytics).

To achieve an adhesion improvement, a very thin layer of a nitrogen-containing

plasma polymer is deposited onto the surface of polyimide films, which binds

copper chemically via complex building. After this a thin copper layer is deposited

through PVD, and then copper galvanic ally reinforced. Finally, the layers are

characterized and the copper adhesion is measured.

Results

Very good adhesion values have been achieved (10 to 14 N/cm in the peel test). The figure on

the left shows a SEM photo of the copper side of the peeled interface. The surface has a

homogeneous appearance. According to the EDX analysis, the ratio C/Cu is 7.9. After the

copper deposit has been peeled off, a thin polymer layer remained on the copper surface,

proving that the break did not take place between the metal and polymer (which is the case

with untreated Kapton), but in the polymer itself (cohesive failure).

A strong adhesion was also retained following the climate test: 24 hours at 85°C and 85%

relative humidity did not cause any significant reduction in adhesion. After one week under

the same conditions, the adhesion value was still over 6 N/cm, while the copper deposited

onto untreated polymer could be easily removed. In the latter case, the copper was oxidized

on its interface with the film (it became dark). In contrast, in the case of the plasma-treated 26

film there was no oxidation apparent, indicating a strong chemical bond between the metal

and the plasma polymer.

The treatment time was reduced to a few seconds by optimizing the process control. This

makes plasma treatment compatible with PVD copper coating. In addition to polyimide as a

film material, other synthetic materials of interest to copper plating are also being

investigated. The adhesion of copper to Hyflon, a fluoro-polymer, could be increased to over

4 N/cm.

Gradient Coatings on Polymers

Good adhesion between the substrate and the functional layer is an essential requirement for

any coating, and is difficult to achieve in the case of hard protective coatings on relatively

soft polymer substrates.

We accomplished it by plasma-chemical deposition of gradient layers, with a smooth

transition from relatively soft organic intermediate layer to a hard, almost inorganic top layer.

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Lateral Micro-Functionalization of Polymers

Miniaturization as well as shortening of analysis time in medical diagnostics and in

pharmaceutical R&D requires new materials with defined bioactive microstructure. An

economically attractive solution for the problem involves surface functionalization of

common polymer materials.

Plasma-chemical microstructuring can be produced on many polymers as the preliminary

stage for biochemical functionalization, e.g. in production of immunological test systems or

in development of cell biochips.

Barrier Coatings

Polymer film based layered systems are suitable for production of flexible materials with

extremely high barrier properties against permeation of gases, water vapour and other

substances. Examples of applications for such ultra-barriers are:

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Packaging films for valuable technical products to insure long shelf life even in

hostile environments

solar modules

thermal isolation materials ("vacuum insulating panels")

impermeable membranes for special equipment, e.g. in contact with chemically

aggressive media

sealing and support materials for flexible displays based on liquid crystals (LCD's)

and organic light emitting diodes (OLED's) .

Improvement of Adhesion of Copper on Polyimide Films

Polyamides (e.g. Kapton ®) are being increasingly used as the carrier material for

printed circuits. Using a plasma-chemical pre-treatment, we could achieve direct deposition

of copper onto polyimide films with high adhesion. This opens a perspective to a new, cost

saving and environmentally friendly technology, improved electric parameters of printed

circuits and weight saving by avoiding adhesive layer.

Applications

the number of applications where plasma is or can be used successfully is very large. Also the

type of application can be very different:

• Wet ability of filter material (paper and synthetic)

• Medical textiles and blood filters Fibers.

Technical textile:-

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• Automobile textiles.

Safety textiles:

• Work wear.

Structural textiles:-

• Fibers for structural composites (building, sportswear) foils.

• Packing material and foils.

CONCLUSION

Plasma technology with all its challenges and opportunities, is an unavoidable part of our

future. The possibilities with plasma technology are immense and numerous. The researchers

are filled with optimism, and product based on their technology is beginning to their mar to

which plasma technology will impact our lives only depends on the limit of human

ingenuinity. It can rightly be said that plasma technology is slowly, but steadily in the

industrial revolution

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