Dyeing And Bleaching Paper 2 WASSCE (SC), 2016

Question 2

  1. Define the term mesh.
  2. Explain two types of mesh
  3. List seven steps of exposing designs onto a mesh.             

 


Observation

Few candidates attempted the question and the overall performance was average. Most candidates were not able to neither define nor explain mesh and its types respectively. This makes them to loose substantial marks. They were expected to respond to the question thus:

 

(a) A mesh is a woven / knitted fabric made of either silk or synthetic fibre and usually fixed to a wooden frame with the use of stapling pins for printing purposes.

 

(b) (i) Fine mesh: It is a tightly woven/ knitted silk or synthetic fabric that allows the penetration of ink through its surface during printing processes. It is usually used for printing on plastics, leathers and non fabric materials.

(ii) Open mesh: It is a loosely/ porously, woven/ knitted silk or synthetic fabric that allows the penetration of ink through its surface during printing processes. It is usually used for printing on fabrics.

 

(c) - Get all materials ready such as bichromate, emulsion, framed mesh, plastic bowl, spoons, transparent glass, etc.

- Mix bichromate with emulsion in a ratio of 1:4 in a darkroom to achieve a deep green colour.

- Apply the chemical solution to the stretched mesh with a neat flat object or a squeegee.

- Spread the chemical solution evenly on the mesh.

- Allow the mesh to dry properly in the darkroom.

- Prepare the design on a tracing / transparent paper with opaque ink.

- Place the design on the coated mesh and put a transparent glass on top of it.

- Hold the mesh and the design with the transparent glass firmly with two hands.

- Expose the mesh to the sun for a few minutes to transfer the design into it.

- Remove the transparent glass and the tracing paper.

- Pour/splash water on the mesh until the desired design comes out clearly.

- Dry the mesh properly for use.