FAQ
FAQ
Here you can find the answers to frequently asked questions about screen making, printing processes and inks applications.
For any other questions or requests, please contact our technical assistance by filling in the form at the bottom of the page.
In order to avoid the problem, it is necessary to apply a transfer which has an anti-bleeding barrier. This barrier is made up of a white base and a metallic aluminium powder (ratio: 70:30).
The printing on dark substrates can be done in two different ways:
- Using water based opaque inks
- Using water based inks for Discharge printing
Wrong curing
Check the curing conditions which, for a silicone ink, must be 130°C for 3 minutes.
Surface treatment of the printing substrate
Make sure that the substrate hasn’t been treated with products which make it unsuitable for printing.
Wrong mixing ratio
Check the percentage of the catalyst.
Too low oven temperature
Check the real oven working temperature, which must be 130°C for 3 minutes (with TEXISIL CATALYST ) or 90°C per 3 minutes (with TEXISIL CATALYST SUPERFAST ).
Too high speed carpet
For an ideal curing, the printed product must stay in the oven for 2-3 minutes.
Humidity in the garment to print
Wrong mixing ratio
Check the percentage of the catalyst.
Product pot-life
After 6-8 hours the product loses its features and is no more printable.
The ink hasn’t been properly thinned
Avoid to add too much thinner not to compromise the ink stability.
Discharge printing is made on dyed fabrics (generally in dark tones). In the printed areas, the colouring of the dye (background) is destroyed by reducers, leaving white areas (coloured if in the paste, in addition to the reducer, there is also a pigment).
Wrong pigment choice
Choose a pigment which is discharge resistant.
Wrong curing conditions
Check the real oven temperature, which must be 150°C.
The mesh is not entirely dischargeable
Check that the mesh is entirely dischargeable.
Wrong number of th/cm
Choose a screen, according to the drawing, which allows to increase the amount of ink on the mesh.
No more discharging power of the ink
Keep the ink always fresh on the screen by frequently adding “fresh” product.
To obtain a foil effect you need to print first an adhesive of the TEXIFLOCK series, dry it into the oven and transfer the selected foil through a press.
To get the best definition it is necessary to respect the right relation between lines-per-cm of the film and the number of th/cm of the screen (1:4 – 1:5).
Wrong ink selection
Select a more suitable ink (please refer to the products technical data sheets) according to the desirable effect.
Wrong ink preparation
Add additive to the ink in order to improve the final touch.
Wrong ink selection
Select an elastic ink (please refer to the product technical data sheets).
Wrong substrate selection
Make sure that the selected substrate is elastic enough to get the desirable effect.
Wrong selection of the number of screen threads
Reduce the number of th/cm according to the drawing, in order to increase the amount of deposited ink and, consequently, the elasticity.
Wrong ink curing
Check the curing conditions. For a plastisol ink it must be 150°C for 3 minutes. Adjust the ink quantity according to the drawing (increasing the ink amount, the elasticity increases).
For a silicone ink it must be 130°C for 3 minutes (with TEXISIL CATALYST ) or 90°C for 3 minutes (with TEXISIL CATALYST SUPERFAST ).
Wrong selection of the ink
Select an opaque ink according to the effect you want to obtain.
Wrong selection of the number of screen threads
Reduce the number of th/cm according to the drawing, in order to increase the amount of deposited ink.
Too high working temperature
Minimize to the bare essentials the power of the drying fans once the machine is set.
Uncovered screen engraving
Always cover the drawing with the ink while the machine is off.
Wrong curing
Check the curing conditions which, for a water based ink, must be 150°C for 3 minutes.
Surface treatment of the printing substrate
Make sure that the substrate hasn’t been treated with products which make it unsuitable for printing.
To obtain all the tones with the four-colour process printing you need to print the colours wet on wet, without intermediate drying with flash lamps.
You can intervene on the ink: select a less covering ink, always according to the final result. You can also intervene on the tools: choose a higher number of th/cm, increase the out of contact of the screen, apply spray silicone on the back of the screens (printing side).
For this effect, you need to pay attention to the curing conditions; you must use the highest temperature that the printing substrate can stand. The higher the curing temperature, the higher the transparency and the brightness of the printing.
You must print FREE ANTIBLEEDING GREY as first color.
To reduce the drying times of a PVC Free plastisol with IR lamps you need to add max 15% of FREE QUICK GEL 557.
The thermoplastic powder can be applied by sprinkling directly on the last printed ink (therefore still wet). Alternatively, you can mix the fine thermoplastic powder with the ink before printing (if you want to increase the transfer tenacity, then use more colours).
Wrong choice of the transfer package
Choose the transfer with the most suitable features for the fabric used.
Dimensional stability of the paper
Condition the paper in the oven in order to eliminate the humidity in the same conditions used to dry the colours. This step is essential before printing the first colour of the transfer.
Paper storage
The paper must be stored in a dry place, protected from humidity, during the various production intervals (e.g. printed paper put in a plastic bag).
Paper “bending” – printing with water based inks
Steady the paper before to start printing. Use polyester substrates which are more suitable for printing with water-based inks.
The screen mesh is not stretched enough
Use screens which have a stretching tension between 18 and 22 N/cm.
The colours are too dry
The colours which make up the transfer, adhesives included, must only be dried and not cured.
Too low transferring temperature
Please check that the transferring temperature is enough for the transfer you are applying.
Wrong composition of the transfer package
Printing a transparent ink as first step grants a higher mechanical resistance to the washing of the Transfer Package.
Wrong preparation of the “film” for the adhesive printing
Prepare the screen for the adhesive printing with a “film” having slightly bigger dimensions than the one of the image.
The adhesive is too dry
The adhesive, as for the other colours which make up the transfer, must be dried but not cured. Therefore, please check the drying conditions of the adhesive.
Unsuitable transferring conditions
Pressure, timing and temperature are fundamental parameters, therefore they need to be suitable. If it is not possible to increase the pressure, then increase the transferring time.
Wrong detachment of the transfer
Handle the garment carefully before the transfer detachment. If the transfer paper tends to rise while moving the garment from the press, the image outlines could remain detached from the garment.
The bleeding problem is linked to the curing temperature, therefore using TEXISIL CATALYST SUPER FAST it is possible to cure the ink at 90°C instead of 130°C. In this case the product pot-life is reduced.
The entire series TEXISIL has anti-foil features; the more the ink deposit, the greater the elasticity of the printing.
To get a glitter effect, use TEXISIL CLEAR BASE as binder adding GLITTERS (max percentage: 20%).
Silicone inks
To get this effect, use TEXISIL PUFF BASE together with the pigments of the series (from 1 to 5%).
Plastisol inks
You can get this effect by using first TEXIPLAST 7000 OP or MS (opaque or semi-opaque plastisol inks) and then adding TEXIPLAST ADDITIVO RIGONFIANTE PF (from 5% to 20%). The puff effect will appear after curing at 160°C for 3 minutes.
Product pot-life
After 6-8 hours the product loses its features and is no more printable.
Too high working temperatures
Minimize to the bare essentials the power of the drying fans once the machine is set.
Too aggressive thinner
Some materials are extremely sensitive to solvents and for this reason we do suggest to use thinners which are not too aggressive (always refer to the technical data sheets of the products).
Too slow drying
If possible, dry the printings into the hot air oven to prevent too aggressive solvents to overly soak into the substrate.
Plastisol inks
To get more opacity on dark substrates, you can directly print TEXIPLAST 7000 OP opaque series. You can get the best results by printing a white plastisol and then, after an intermediate drying, overprinting with TEXIPLAST 7000 PROCESS , MS or OP.
PVC FREE plastisol
To get more opacity on dark substrates, you can directly print FREE OP SERIES opaque series. You can get the best results by printing FREE FLASH WHITE and then, after an intermediate drying, overprinting with FREE PROCESS, COLOURS or OP.
The ink hasn’t been properly thinned
Avoid to add too much thinner not to compromise the ink stability.
Wrong operating parameters
Check the out of contact, the pressure and the printing speed and the squeegee tilt angle.
Wrong drying conditions
Make sure that the used plastisol adhesive hasn’t been cured but simply dried.
Wrong transfer conditions
Make sure that the transfer conditions are the ones indicated in the product technical data sheet.
Wrong drying conditions
Make sure that the colours previously printed haven’t been cured but simply dried.
The ink hasn’t been properly thinned
Avoid to add too much thinner not to compromise the ink stability.
Wrong curing
Check the curing conditions which, for a plastisol ink, must be 150°C for 3 minutes.
Surface treatment of the printing substrate
Make sure that the substrate hasn’t been treated with products which make it unsuitable for printing.
Too low oven temperature
Check the real oven working temperature, which should be around 150°C.
Too high carpet speed
For an ideal curing, the printed product must stay in the oven for 2-3 minutes.
The ink hasn’t been properly thinned
Avoid to add too much thinner not to compromise the ink stability.
The photoemulsion has been overexposed
Adjust the exposure time using the exposure meter.
The film used for the engraving is low quality
Make sure that the film is really opaque.
The coated screen has been put through an extreme heat
The drying temperature of the screen cannot exceed 35°C.
The film to be engraved is not perfectly tight to the screen
Check the efficiency of the vacuum of the engraving press.
Wrong polymerization conditions
A cylinder for textile rotary printing must be cured at 180°C for at least 60 minutes in order to be used.
Wrong mesh tension
Make sure that all the screens used for the work have the same tension.
Wrong placement of the screen to be engraved
Engrave the screens considering the required space for the squeegee and the scraper.
Wrong use of the recovery product
Apply POLISTRIP PASTA with a brush on both sides of the screen, let it work for 5 minutes and rinse it with a high pressure nozzle.
The photoemulsion has been catalyzed
In that case it is not possible to recover the screen.
Wrong use of the adhesive
The adhesive used to stick the mesh to the frame has not been prepared properly. Check the percentage of the catalyst.
Drying time
Make sure the adhesive is completely dry before taking off the screen form the tension system.
Use of aggressive products
Avoid extended contacts between the screen and the washing solvents.
Bad observation of the time instructions
Avoid, if possible, to prepare the screen for the printing on the same day in which it has been stuck.
Lack in screen cleaning
Clean the frame before tensioning the screen.
Wrong maintenance of the coated screens
Photoemulsions are extremely sensitive to the ultraviolet radiation. For this reason, they need to be sensitized, used and kept in light screened rooms. The same rule is valid for coated but not yet engraved screens.
Check the printing parameters
If possible, adjust the printing pressure, reduce the out of contact and sharpen the squeegee.
Wrong exposure (under exposure) of the coated screen
Adjust the exposure time using the exposure meter.
The quantity of photoemulsion is not enough
Do coat the screen on both sides and, eventually, lay a second coat on the printing side.
The selected photoemulsion doesn't adapt to the ink used
Use a photoemulsion which is suitable to the printing process and to the solvents which could eventually be used.
Wrong printing parameters
Check the printing pressure according to the out of contact.
Worn screens
Don't use printing screens which have been recovered too many times.
Wrong exposure (over or under exposure) of the coated screen
Adjust the exposure time using the exposure meter.
The selected photoemulsion is not suitable to reproduce fine details
Select a more suitable product.
Light loss
The light loss of a white mesh can cause resolution loss. Use a coloured mesh, a yellow one for example.
Wrong choice of the th/cm number in relation to the drawing to be reproduced
Consider the relation 1/4 or 1/5 between the lines per cm of the film and the number of threads to use (e.g.: with a 25 lines/cm drawing it is necessary to work with at least a 100 Th/cm mesh).
The thickness of the photoemulsion is unsuitable
Adjust the photoemulsion thickness on the screen, by changing the application process.
Light loss
The light loss of a white mesh can cause resolution loss. Use a coloured mesh, a yellow one for example.
For this kind of work we suggest to use a mesh with a medium number of threads (43-55th/cm). The most suitable emulsion is ZERO-IN KS200 (for operating instructions please refer to the technical data sheet).
The photoemulsion is not perfectly dry
Let the coated screen dry completely.
The screens are not perfectly dry
Check the efficiency of the air re-circulation into the drying oven.
The photoemulsion is not perfectly dry
Let the coated screen dry completely.
The screens are not perfectly dry
Check the efficiency of the air re-circulation into the drying oven.
Wrong mesh stretching tension
Too low stretching tension values (under 18 th/cm) cause a flexion during the passage of the squeegee, therefore the thickness of the photoemulsion will be higher on the sides and lower in the middle of the screen. Check the stretching tension of the mesh using a tensiometer.
Check the photoemulsion application system
Prefer an automatic system to the squeegee, especially in case of medium and large format screens.
Check the edge of the squeegee
Make sure that this edge is completely smooth, without any scratches. Otherwise adjust the outline or eventually change the squeegee.
Presence of lumps or dry residues in the photoemulsion
Do not mix an old product with a new one. If necessary, pre-emptively filter the product.
The mesh hasn’t been properly degreased
It is recommended to accurately clean the mesh, by using CLEANSER 100 (for operating indications, please refer to the technical data sheet).
Presence of oil or grease in the working tools
It is recommended to accurately clean all the tools before use.
Wrong choice of the photoemulsion
Choose the photoemulsion according to the ink selected for printing (e.g. of wrong choice: solvent resistant photoemulsion used with water based products).
Use of aggressive products
Avoid the excessive use of thinners and limit the use of solvents during washing.
Presence of dust and dirt in the squeege
Work in a suitable working environment and keep all the tools always clean.
The mesh hasn’t been properly degreased
It is recommended to accurately clean the mesh, by using CLEANSER 100 (for operating indications, please refer to the technical data sheet).
The sensitized photoemulsion hasn’t been properly de-aerated
The product needs the required time to get rid of the gaseous mixture produced by the reaction between photoemulsion and sensitizer.
Wrong choice of the photoemulsion
Choose the photoemulsion according to the ink that is going to be printed on it and to the number of th/cm (e.g.: a photoemulsion with low viscosity is not suitable to prepare a screen with 32 Th/cm).
Too much distance between the mesh of the screen and the squeegee
Check the distance between the mesh of the screen and the squeegee.
Low power lamps
Check the real power of the lamp by using a radiometer.
Lamps age
The lamp efficiency tends to decrease while using, for this reason it is better to check their lives (average life: 1000-2000 hours).
Too much ink deposit
Check that the quantity of the ink deposit is proportional to the energy emitted by the UV lamps.
Surface treatment of the printing substrate
Onto certain kinds of substrates it is necessary to make a surface treatment before printing. Check the treatment effectiveness or eventually do it once again.
Scarse drying – Increase, if possible, the oven temperature compatibly with the material used for printing.
Too slow thinner – Select a thinner with a faster evaporation.
UV inks
Scarse polymerization – Check the real power emitted by the lamps, if necessary switch on another lamp or decrease the carpet speed.
Ink performance – Add to the ink some concentrate photoinitiator, in order to make it more reactive under UV lamps, or some anti-blocking additive.
Too hot printing substrate – Uv lamps and polymerization generate heat and they warm the printing substrate up. We do suggest to let the pieces cool down before to pile them up.
Printing parameters
Adjust “out of contact”, speed and printing pressure. Eventually check also the screen tension.
Too high ink viscosity
Add some thinner to reduce the viscosity and mix properly before use.
Printing substrate
Check the chemical nature of the printing substrate and select the most suitable ink. Check if the substrate has a printing side.
It is necessary to use a screen with a photoemulsion thickness being adequate to the result you want to obtain. You can get a 3D effect only by printing transparent, or lightly coloured, UV varnishes.
Too high ink viscosity
Add the adequate reactive thinner in order to reduce the ink viscosity, without exceeding 10% in weight.
Printing parameters
Adjust “out of contact”, speed and printing pressure. Eventually check also the screen tension.
Too high ink viscosity
Add some reactive thinner to reduce the viscosity and mix properly before use.
Scarce polymerization
Check the real power emitted by the lamps, if necessary switch on another lamp or decrease the carpet speed.
Too much ink deposit
Check that the quantity of the ink deposit is proportional to the energy emitted by the UV lamps. Alternatively, increase the number of th/cm according to the desired effect.
Printing substrate
Check the chemical nature of the printing substrate and select the most suitable ink. Check also if the substrate has a printing side.
Surface treatment of the printing substrate
With certain kind of substrates it is necessary to make a surface treatment before printing. Check the treatment effectiveness or eventually do it once again.
Low power lamps
Check the real power emitted by the lamps through a radiometer.
Too much ink deposit
Check that the quantity of the ink deposit is proportional to the energy emitted by the UV lamps.
Concentration of the black pigment
All conditions being equal, a black ink has a polymerization speed which is halved compared to a yellow one. This is due to the absorption of the light by the black pigment. For this reason, it is necessary to increase the lamp power.
Colour of the printing substrate
Light colours reflect the radiant energy making the ink film more reactive, while the dark or transparent substrates tend to absorb more energy. It is therefore necessary to compensate the greater absorption whit a more powerful UV lamp.
The mesh hasn’t been degreased properly
It is recommended to accurately clean the mesh, by using CLEANSER 100 (for operating indications, please refer to the technical data sheet).
The photoemulsion is underexposed
Reconsider the exposure time (thanks to the exposure meter) and check the life of the engraving lamp.
Wrong exposure conditions
Check the temperature of the development water, that needs to be around 30°C. Check also the water pressure, if using a high pressure nozzle.
The photoemulsion was sensitized too long ago (pot-life)
Always note down the photoemulsion sensitizing date and follow the instructions on the technical data sheet of the product.
The screens have been engraved when not completely dry
Check the efficiency of the air re-circulation into the drying oven.
Apply the product CLEANER STRIP PASTE on both the screen sides: let it work for 15-20 min then rinse it with a high pressure nozzle. This product together with SOLVENT STRIP is even more effective.
It is possible to recover a cylinder for textile rotary printing only before the polymerization, by using products of the series POLISTRIP and SOLVENT 610 (for operating instructions please refer to the technical data sheet).
To increase the mechanical resistances you need to protect the printing side of the screen with the products of the series DURAL ARCHIM (for operating instructions please refer to the technical data sheet).
The photoemulsion must be kept in places with screened light. Once sensitized it is better to keep it in a refrigerator or in cool places not to compromise the stability and the characteristics of the product. The same rules are valid also for the sensitizers.
Place the screen under a UV lamp making sure to re-expose both the coated sides. The re-exposition increases the general fastness of the photoemulsion.
The only product suitable for the realization of high thickness screens is ZERO-IN SPEEDCURE (for operating instructions please refer to the technical data sheet). It is a blue ready to use photoemulsion which doesn’t require any sensitizer.
For this kind of work we recommend to use ZERO-IN SV PLUS violet photoemulsion (for operating instructions please refer to the technical data sheet).
To increase the mechanical resistances of the used photoemulsion, we recommend to catalyze it with one of the following products:
Catalyst 200, Catalyst 210 and mono nf for polyester fabrics, Catalyst 206 for nylon fabrics. For operating instructions please refer to the technical data sheet.
Using one of these products, the screens cannot be recovered.