ARTEQUIM,QUALITY CONTROL OF PAPER,QUALITY CONTROL FLEXIBLE PACKAGING,QUALITY CONTROL OF PLASTIC FOAM,MATERIAS QUALITY CONTROL

1. - Technology of Paper

1.1.1 generalities

1.1.2 quality control of paper and cardboards

2. - Technology of Plastic

2.1 films or flexible packaging

2.1.1 generalities

2.1.2 quality control of films or flexible packaging

2.2 expanded plastics, foams

2.2.1 generalities

2.2.2 quality control of expanded, foams

3.- Correlation of properties in papers, films , expanded and foams

Development :

1. - technology of the Paper

1.1.1 generalities

The paper is formed by natural fibers of Cellulose, recycled paper and chemical additives. Important in the obtaining of the type or final quality of a paper, is the manufacture process to that they undergo the essential components of the recipe of production of the paper.

In rigor two types of papers exist : Flat or planes and crepe or Tissue paper.

Flat papers or planes : Sulphite , Kraft , Cardboards , self-copy paper , monolucid , Couché , Printing , Bond , thread paper, Special .

Tissue : Napkins , Hygienic of Bathroom , Towels kitchen , Sheet paper doctors , Handkerchiefs , Diapers and feminine Towels .

Chart 1.1. - Density and Thickness in more common papers.

Type of Paper Density Thickness

grs./m² mm

Flat or Plane

20 30

56 52

60 102,5

80 109

90 115

106 135

140 185

180 225

225 265

240 290

Tissue 20 110

21 115

25 140

44 240

Grs: Gram

m²: square meter

mm: micron, or thousandth part of a millimeter.

1.1.2 quality control of Paper and cardboards

In general the paper machines are designed to work with a minimum of error in their main variables (± 0.5 of the unit in study)

Thickness ( e )

Elongation ( E )

Resistance ( s )

Humidity ( H )

Superficial Density ( grs / m²)

All these variables are managed with physical process and chemical additive to obtain the wanted product.

The secondary variables are:

Color

Sense of Court

Properties Thermographics

Properties for Impression

The main variables to control in the reception of the paper and cardboards are:

Size (dimensions)

Texts and Colors

Superficial Density ( gram / m²)

It is more important to control the superficial density ( gram / m²), of the paper and cardboard before the thickness, because this variable, (thickness), it is easily modifycable for incorporation of chemical additives, or physical process (laminate or engraving). The variable gram / m² is unalterable since in the face of any change in the process or in the composition, the result is reflected immediately in the value of this. The cellulose makers, paper and derived, uses the variable gram / m² ( lb / in² ), as fundamental unit in its product.

In general the plane paper is revised in:

Superficial Density ( Grs / square meter )

Size and Color

Resistance to the use

and the paper Tissue (hygienic, towels, sheet papers doctors, napkins) in:

Superficial Density ( Grs / square meter )

high of the roll ( h )

diameter of the cone of sustentation ( d )

long of the paper (extension of the paper when uncoiling) ( L )

external diameter of the roll ( D )

long and wide ( napkins )

In the case of printed papers they should be controlled:

Superficial Density ( Grs / square meter )

texts

logos

quality of the application of the ink

quality of the form, especially if flaws of Moire appear

quality of the engraving

the self-copy papers are revised in the impression transfer.

Necessary tools for the effective control:

1. - training to the personnel in charge of managing these products

2. - scales or rules of appropriate measures for the longitudinal measurement

3. - range of normalized colors, for the verification of colors.

4. - Superficial Densimeter, for the ( gram / m²) control

5. - lens or glass magnifying printer or it counts thread, for revision of impressions

6. - adhesive tape for revision of the impression (adherence)

7. - art y/o description of the impression process

8. - instruments and teams for product revision to bulk

9. - devices y/o machines that are developed for each application.

10. - norms Tappi, Din, Iso, ASTM, or others.

11. - transparencies for revision of impressions.

2. - technology of Plastic

2.1 films or flexible packaging

2.1.1 generalities

The film ( it packs flexible ), case of bags or packaging, it is formed by derived fibers of the petroleum and chemical additives.

Films

Polyethylene of Low Density (LDPE)

Polyethylene of High Density (HDPE)

Polypropylene monoriented (OPP)

Polypropylene bioriented (BOPP)

Polystyrene (PS)

Policloruro of Vinyl (PVC)

Plate

PVC

PAI

BOPPP

Chart 2.1. - Density and Thickness in more common Plastics

films Density Thickness

gram / m² m m

BOPP 25 24

32 30

35 32

HDPE 15 14

21 20

23.5 22

28 26

LDPE 25 28

30 30

50 48

100 88

120 104

220 182

PS 27 30

29 32

PVC 30 42

95 116

150 184

2.1.2 quality control of films or flexible packaging

In general you scheme them extrusion machines of films they are designed to work with a minimum of error in their main variables (± 0.5 of the unit in study).

Thickness ( e )

Elongation ( E )

Superficial Density ( gram / m²)

Resistance ( s )

All these variables are governable with physical process and chemical additives to obtain the wanted product.

The secondary variables are:

Color

Softness

Properties of Resistance to use conditions

Block off ( stick )

The main variables to control in the reception of the films or flexible packaging are:

Superficial Density ( Gram / square meter )

size

texts and colors

It is more exact to control the superficial density (gram / m²), of the films or flexible packing, before the thickness, because this variable, (thickness), it is easily modificable for incorporation of chemical additives or physical process.

In general the films or flexible packaging is revised in:

Superficial Density ( Gram / square meter )

size and color

texts and colors

Resistance to the use

In the case of films or flexible packing, forms impression should be controlled:

texts

logos

quality of the form

Necessary tools for the effective control:

1. - training to the personnel in charge of managing these products

2. - scales or it rules of appropriate measures for the longitudinal measurement

3. - range of normalized colors, for the verification of colors.

4. - Superficial Densimeter, for the gram / m² , ( lb / in² ) control

5. - lens or glass magnifying printer or it counts thread, for revision of impressions

6. - adhesive tape for revision of the impression (adherence)

7. - art y/o description of the impression process

8. - instruments and teams for the product revision to bulk

9. - devices y/o machines that are developed for each application

10. - norms ASTM, Din, Iso, or others

11. - transparencies for revision of impressions.

2.2 expanded plastics, foams

2.2.1 generalities

The expanded plastics, and foams they are derived products of the petroleum and chemical additives.

expanded plastics, foams

Expanded Polyestyrene

Polyurethane of open cell

Polyurethane of closed cell

Chart 2.2 Volumetric density of expanded and more common foams

Density

gram /cm³

PS 25

PUoc 15

23.5

PUcc 25

PS: Polystyrene

PUoc: Polyurethane open cell

PUcc: Polyurethane closed cell

2.2.2 quality control of expanded Plastic and foams

In general you scheme them inyection machines of having expanded and foam they are designed to work with a minimum of error in their main variables ( ± 0.5 of the unit in study), and the final product depends under great measure of the molds and physical conditions of the process.

The main variables to revise in those expanded and foams they are:

Volumetric density of moulding process ( dv )

Elongation ( E )

Relationship of components

Resistance to the compression ( s_c)

Dimensions

All these variables are governable with physical process and chemical additives to obtain the wanted product.

The secondary variables are:

Resistance to the traction ( s_t )

Resistance to the cut (s_e)

Graveness specifies before moulding process

Color

Properties of Resistance to use conditions

The main variables to control in the reception of the products of having expanded and foam they are:

Volumetric density

Dimensions

Color

It is very important to control the volumetric density of expanded and foams, because this variable, will tell us the type and quantity of mass that it contains the acquired product. moreover is facility alteration for incorporation of chemical additive, o physical process.

Necessary tools for the effective control:

1. - training to the personnel in charge of managing these products

2. - scales or rules of appropriate measures for the longitudinal mensuration

3. - Volumetric Densimeter, for the gram / cm³ ( lb/ in³ ) control

4. - instruments and teams for the product revision to bulk

5. - devices y/o machines that are developed for each application

6. - norms Din, Iso, ASTM, or others

3.- Correlation of properties in papers , films , expanded and foams

the aplication of criterion of plastic deformation and anisotropy, to papers , films or flexible packing , expanded and foams :

N = < e > / < s > * ( d < s > / d < e > ),

s = s_o( 1 + b e^N ),

R = Ln ( w / w_o) / Ln ( t / t_o ),

and the combination of the properties : superficial density, volumetric density, cuaternary density, deformation ( e ), resistance ( s ), molecular diameter ; they allow us to appreciate a phenomenon; that even existing anysotropy the paper behavior , films or flexible packaging , expanded and foams ; it completes what we have called , " the quadrature of the properties " of these materials. the productive application of this simulation methodology helps to reduce the times of set - up in changes of types of products, or recipe changes. in the behavior graphics, . . . . . .

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