Testing of Semi rigid Packaging materials

Folding Cartons

The important tests and their significances are given below :

Significances and Tests of Important Parameters

(a) Grammage

Significance : To measure of weight of paper board expressed in gms/square metre. It is also called as substances and popularly known as grammage.

Test Method : The test method is same as for paper or kraft liner 

(b) Thickness or Caliper

Significance : It is to determine the thickness of paper board used for making the folding carton. It is important for the design and development of folding carton.

Test Method : The test method is described in next section

(c) Stiffness.

Significance: To determine the rigidity of paper board so as to make the assessment about load bearing capacity of product in folding carton.

Test Method : Test method is explained in IS: 4060 – Part-II- 1987. The values are expressed in Taber or kenley or milliNewton (MN).

(d) Brightness :

Significance : The objective is to measure the brightness in percentage.

Test Method : The test method is explained in IS : 1060 – Part-II, 1987.

(e) Surface Oil Absorption Time (SOAT)

Significance : To determine the characteristics of paper board about the absorption capacity of surface oil, which depends on the quantity of sizing and filler materials exists on the paper board.

Test Method : The test specimen of paper board is placed on the table. Then two drops of printing inks are put on the board and allowed to penetrate inside.The time taken to absorb ink completely by the board is recorded. Off set inks are oil based which acts as a vehicle. High soat indicate penetration of ink will be slow drying of ink as well as set off.

(f) Moisture Content

Significance: The objective is to determine the presence of moisture content in percentage in the paper board.

Test Method: Test method can be referred in IS: 1060 – Part-I 1987.

(g) Water Absorption or Cobb Value

Significance : The objective is to determine the water absorption capacity of board or cobb value.

Test Method : Test method is explained in IS: 4060-Part-II-1987

(h) Surface Smoothness

Significance : The objective is to measure the smoothness of board. This is important to get the good quality of printing.

Test Method : The test specimen is exposed to the testing equipment & then surface smoothness is measured in terms of ml/sec.

(i) Physical Observation

Significance : To check the physical properties of the paper board.

Test Method: The samples are checked physically to check properties like appearance on spots, speaks, loose fibre / waviness prior to accept for conversion into folding carton.

(j) Folding Endurance :

Significance: To determine the sustainability of duplex board against double fold.

Test Method: The test specimen of 15 mm x 76 mm are cut and then clamped into the machine. The test is run till the samples get torn due to double fold. This will indicate the sustainability of duplex board and this is expressed in terms of No.of double fold.

(k) Compression strength

Significance: To measure the load bearing capacity of folding carton.

Lined Carton

Significances and tests of important parameters :

Paper Board Carton :

(a) Stiffness :

Significance : To measure the resistance of the carton against bulging, crushing, and bowling of the sides. Low stiffness of the board causes to less compression strength and stackability of cartons.

Test Method : The test specimen is subjected to stiffness equipment and the test values are measured in machine direction (MD) and cross direction (CD).

(b) Moisture Content :

Significance : It is very important to asses the moisture content of paper board.

Test Method: The details of test method is given in 2.7.1. Normally, the paper board is having moisture content between 6 to 9 %.

(c) Caliper

Significance: To check the thickness of paper board.

Test Method : The test specimen are measured by means of digital or mechanical micrometer and the values are expressed as micron or millimeter.

(d) Grammage

Significance: To measure the weight of paper board in gms. High grammage board offers resistance against bursting, puncturing and tearing.

(e) Ply Bond Strength :

Significance: This parameter pertains to the strength of the inter layer bond in the board. If the ply board is less, these layers would have a tendency to separate, particularly during creasing.

Test Method: The test specimen are taken and then place in between two metallic plates, subjected to heat and then observe the degree of separation of layer. No separation will indicate good ply bond strength.

(f) Surface Appearance :

Significance: This test is important as attributes relevant pertain to brightness, smoothness, oil absorption capacity and blemishes affecting surface finish.

Test Method: This is a subjective method and the observations are taken visually. However, the laboratory tests on brightness, smoothness, SOAT etc. are also conducted to assess the overall surface appearance of lined carton.

Liners

(a) Barrier Properties

Significance: To measure the barrier properties in terms of water vapour transmission rate and oxygen transmission rate as these properties have got direct effect on the degree of deterioration of dairy product and thus affect the shelf life of products.

Test Method: The details are described in IS : 1060 – Part-III and ASTMD 3985.

(b) Treatability

Significance: To measure the level of treatability or the surface energy of the film or laminate.

Test method: Normally, the energy level should have more than 38 dynes/cm.

(c) Peel Bond Strength :

Significance: To measure the force require to separate the two plies of the laminates.

Aseptic Cartons

Significance and Tests of Important Parameters

The significance and test method of important parameters are as below:

 (a) Delamination of Laminate & Thickness & Grammage Significance : The objective is to separate all the important layers and to check the thickness and grammages of layer.

Test Method : The details are given in IS : 1060 – Part-I – 1985.

(b) Leakage Test for Aseptic Carton

Significance : To check the integrity of the seals of the carton and to assess the leakage.

Test method : A filled aseptic carton is immersed into a beaker filled with water. Keep it for 15 minutes and take the observation about the appearance of any air bubbles through the water. This will clearly indicate about the integrity of seal or leakage properties of aseptic carton.

(c) Barrier Properties

Significance : To check the barrier properties of the laminate against moisture, Oxygen gas, light etc.

Test Method : The detail test methods are explained in next section.

(d) Mechanical Properties :

Significance : The objective is to determine the mechanical properties of the laminate inorder to ascertain about various parameters like tensile strength, stiffness, tear properties, bursting strength etc.

Test Method : The test method of paper based laminate is same as paper and paper board.

(e) Dimensional Stability :

Significance : The objective of this test is to determine the dimensional stability of the laminate.

Test Method : The test specimen is measured for all the dimensions like length, width and height. The sample is then exposed to high temperature & high humidity i.e. 38°C ± 1°C & 90% ± 2% R.H.

(f) Flex Crack Resistance :

Significance : This test is conducted to determine the performance of laminate in terms of resistance against flex crackness.

Test Method : The test specimen is cut into a size of 30 cm x 20 cm. And then the laminate is clamped into Gelbo flex Tester and then run the machine for 2800 cycles.

Thermoformed Containers

Significances and Tests of Important Parameters.

The important parameters are considered for the qualitative tests. The details are as follows :

(a) Identification of Polymeric Materials.

Significance : The main objective of this test is to determine the kind of plastic materials used for making thermoformed containers.

Test Method : The chemical method is normally employed for the identification purpose.

However, differential scanning calorimetry (DSC) is also used for the identification of polymetic materials.

(b) Extractability Test

Significance : To check the level of extractable residues so that to ascertain about their suitability for processed food products.

Test Method : The testing is done in the laboratory by referring IS:9845 – 1987.(Migration test).

(c) Product – Package Compatability Test.

Significance : This test will ascertain about their suitability for the packaging of particular product. In other words, the test will confirm about compatability due to interaction during storage, handling and transportation.

Test method : In the laboratory, the thermoformed containers are filled with particular type of dairy product. Then the filled packages are exposed to accelerated condition i.e. 38°C ± 1°C and 90% ± 2% RH for specified period of time.