Technique 8: Bleaching and Rastering

Dyeing with Bleach:

Dyeing fabric with bleach is the idea of creating uniquely colored or patterned fabrics by removing the colour of the original fabric.

Materials: 

  1. Bleach
  2. Spray bottle or brush or dripper
  3. Cotton fabric (coloured)
  4. Objects chosen as a stencil- e.g. rubber bands, bottles caps, tapes, etc

Steps Needed: 

  1. Fill the bottle with a desired amount of bleach.
  2. Cover table with plastic to protect the table.
  3. Place the cloth and stencils chosen on the table.
  4. Spray bleach over the cloth and leave it for approximately 10-15 minutes to see the effect.

Trials #1: 

I sprayed the bleach over the cloth randomly and attempted to scrunch the cloth at certain areas, hence explaining the creases. This is the final result.

Trials #2: 

I tied the cloth in certain areas using rubber bands, hoping to have the spread out radial kind of effect from the bleach. However, that did not work too well and turned out to look like random bleach spots.. This is the final result.

Overall, I feel that the bleach is a little hard to control as it does not accommodate mistakes or slips very well. We can learn to have better control over how the bleach flows and sprays and perhaps make more interesting organic shapes from printing daily object surfaces on the fabric.

Applications:

Tie-dye bleach jeans.

Painting on fabrics with bleach- portraits and beyond.

Bleach dye canvas tote bags

Creating unique patterns on fabrics with bleach.

Rastering:

Procedures: [can be obtained from product design ADM website]

 1) Preparing File (Export from Rhino)

Vectors are needed in the CorelDRAW for clean and efficient laser cutting. Rhino is one of those software’s that exports vector curves and shapes. *.DXF format is the optimal format to be used in the laser cutting.

2) Starting the Laser Cutter

Before using the machine, please ensure that everything that’s necessary to operate the machine safely.

3) Turning on the Compressed Air

Here is another clip that shows you how to turn on and adjust the compressed air. Please do this step as soon as the machine is started,

4) Laser Focusing

Laser focusing determines the laser intensity that passes through the materials that you are cutting. Laser will not cut properly and efficiently if it is off-focused. In some cases, if may even ignite, damaging the laser machine in the process. Watch the clip to learn how to focus manually.

5) CorelDraw Settings

In CorelDRAW X3, follow the instructions in the video for proper settings. This step is very important as it will determine the final outcome of the cutting.

6) Print Layout & Setup

Setting page layout helps calibrating the canvas dimensions that you are printing on.

​​Before proceeding to printing (laser cutting), Print Setup is an important procedure as it determines the nature of this cutting session. A list of settings and details has been provided on the right side of the page for reference

Samples of rastering done: 

  

Trial:

I tried rastering text on acrylic. I wanted to see how a simple “Hello” turns out. The effect is quite nice since the words are white after rastering. I also laser cut a few small squares/ rectangles.

In summary, the effects of rastering are more defined on acrylic than on wood. However, if one prefers to have the gradient effect where there are slight changes to the colour of the raster, giving the piece some depth, I think the wood will be a better choice.

Applications:

Creating cool board games on acrylic.

Raster portrait art:

Personalised photo frames:

THERMOCHROMIC INK PRINTING:

Thermochromic ink (also called thermochromic ink) is a type of dye that changes colour when temperatures increase or decrease. Often used in the manufacture of many toys or product packaging, as well as thermometers.

Materials used:

  • Fabric- with a lighter background
  • Silkscreen
  • Thermochromic Pigment
  • Cups for mixing
  • Spoons for mixing
  • Plastic bags to lay the table before silkscreen printing
  • Silkscreen Printing Clear Base
  • Squeegee

Steps:

1) Mix the thermochromic pigment powder with clear base in the ratio of 1:3 in a paper cup. Be careful not to inhale the powder during the process. (Avoid talking/ laughing)

2) Lay the table with plastic sheets to avoid any transfer of the mixture onto the table.

3) Lay 1-2 layers of tissue onto the plastic sheets before placing your fabric on top.

4) Put down the silkscreen on top of the fabric.

5) Scoop the mixture with the spoon and spread the desired amount along the edge on the silkscreen (blue area).

6) Make sure the silkscreen prepared is secured and ideally have someone to hold the silkscreen frame for you.

7)  Hold the squeegee along the edge with the mixture and tilt it to 30 degrees.

8)  Swipe it evenly to the other end of the silkscreen forward and backwards to make sure that the colour spread throughout the silkscreen.

9) Hold the fabric down and lift the silkscreen slowly.

10) Remove your fabric and let the ink dry.

11) Put the silkscreen and the squeegee propped up on a cup for the next person to use.

My outcomes:

Trial #1:

I tried the grey colour first.

Trial #2:

Followed by the red.

Trial #3:

And eventually, trying out a gradient colour scheme of yellow and red.

Trial #4:

For the 4th attempt, I tried the wooden block printing method where we had to place some mixture on the plastic sheet and spread it out evenly before placing the wooden block on the mixture.

For my very first stamp on the upper right, I forgot that we had to stamp on the tissue laden area and hence resulted in this uneven thickness of prints. Subsequently, I printed on the soft area and the prints turned out better.

HEAT TEST: 

I used the hot air gun to do a heat test for the piece with red ink and this is the result.

Overall, I think thermochromic printing is very interesting and yields satisfying results. It could be very useful in making “smart fabric” that reacts according to one’s body heats or their surroundings.

PART 2: VACUUM FORMING

Materials used:

  • Vacuum forming machine
  • Scissors to cut the PVC sheet to your desired size
  • Mould or object

Steps:

Cut the PVC sheet to the desired size according to the shape and size of the chosen object.

Secure the metal plate and place the object in the middle of the vacuum forming machine is an upright manner.

 

Lower down the object into the machine using the handle.

Place the PVC sheet in the designated area of the vacuum forming machine.

Pull the overhead lid over and cover the PVC entirely.

Wait for 30 to 45 seconds for the PVC to get heated up.

When the PVC sheet is ready for moulding, push the lid back. Pull the handle down and switch on the air pump simultaneously.

Once the mould is successfully formed, remove the PVC and the object.

My attempt:

For the first attempt, I didn’t grasp the pulling of the handle and the suction well enough, resulting in the mould having very blunt edges.

For the second attempt, it was slightly better and you could see that the edges became more defined.

Overall, I think vacuum forming is a fast and efficient process to get the desired mould done up, especially for resin or silicone moulding purposes. However, I think it is advised not to stay around the vacuum machine for a long time as the fumes emitted made me a bit nauseous after a while.

Applications: 

The wrapper on chocolates to know if the chocolate may be melted or not.

Vacuum forming: 

Vacuumed formed chopping board.

Plastic dividing drawer.

 

 

Thermoplastics:

thermoplastic is a material, usually, a plastic polymer, which becomes softer when heated and hard when cooled. Thermoplastic materials can be cooled and heated several times without any change in their chemistry or mechanical properties. When thermoplastics are heated to their melting point, they melt to a liquid.

For the class, Prof Galina gave us a sample- 100% organza- and hence I also used the same for the thermoplastic class.

Materials used: 100% polyester fabric, marbles, aluminium foil, rubber bands.

Steps:

1) Cut the organza into the desired sample size.

2) Wrap the organza around the selected objects and tie them with rubber bands whenever necessary.

3) Wrap the completed design with a layer of aluminium foil.

4) Put into the pot to cook for about 1 hr. Remember to do it outside as the fumes emitted from the polyester could make you feel dizzy and nauseous.

5) Remove the wrapped piece and leave it to cool before removing the layer of aluminium foil and all the objects wrapped in the polyester.

Process and Trials:

Trial #1: 

I made use of marbles of different sizes as well as aluminium foil. I wrapped the marbles with the organza and tied them with rubber bands. I also tried twisting the organza into sharp pointy cones and wrapped the cones with aluminium foils.

Trial #2: 

I made use of aluminium foil as the origami mould for the organza. Cut the aluminium foil twice the size of the organza sample. Sandwich the organza in between the aluminium foil and start folding it in the desired manner.

This is the eventual shape I am hoping for my organza sample.

Trial #3: 

For the third attempt, I was going for the curled ball abstract look for the organza. Hence I literally wrap the organza in between the aluminium foil and crushed it into a ball.

For identification purposes, I tied green threads around my 3 trials and coloured rubber bands.

INTO THE POT

Put all the trials into the pot to boil for about 1 hr. Remember to do it outside as the fumes emitted from the polyester could make you feel dizzy and nauseous.

End Results:

Trial #1: 

 

Trial #2: 

Trial #3: 

Overall, I think that the process of experimenting with thermoplastics fabrics is really interesting and that choosing the right fabric that is able to hold the shape is very important. I felt that my experiments are quite successful to some extent and the shape did eventually form to the desired ones I had in mind.

Applications:

Technique: Knitting is a process of using long needles to interlink or knot a series of loops made by one continuous thread. Each loop or knot connects to another one, and when enough loops have been made, the result is a flat piece of material called a textile.

Materials: Yarn, knitting needle or equivalent (I used pencils and satay sticks)

For someone who has never tried knitting before, it was a little hard to get the hang of it and I am often confused by” which loops go into which loop”. We were taught the purl stitch in class and the following are the steps to complete a purl stitch.

Steps: Firstly, we need to make a cast-on whereby we get the first row of stitches onto the needle. I find this short video very useful.

Afterwhich, I would follow these steps to continue knitting.

Here is how it looks like for mine:

  1. Firstly, insert the needle from the bottom of the first loop from right to left.

2. Wrap the yarn around the stick.

3. Push the wrapped yarn through the loop,  out from the other side and push the original loop our from the stick on the left.

4) First round of loop done and continue knitting.

This is a close look at my knitting sample. Originally, I was using 2B pencils to knit, resulting in having bigger loops as observed in the upper portion of the picture. After knitting for a while, I switched to thin satay sticks and the knits became a lot closer and tighter to each other.

Overall, I felt that knitting was fun and once you get the hang of it, it becomes rather mechanic. there are different styles of knitting and I will like to explore more about the different types of yarns and knitting techniques. I will update further if I make more samples with different yarns.

Applications: 

knitted products: