Chete glass packaging

20th century

The shift in glass manufacturing at the turn of the ______ represents one of the most significant leaps in industrial history

Crown cork system

The most perfect system of bottler stoppering invented

William Painter

The "Crown Cork" seal, patented by _____ in 1892, required a standardized rim to prevent leaks and carbonation loss.

Automatic Bottle Machine (1903)

Michael Owens’ invention of the ___________ is often cited by labor historians as a more effective tool for social change than many early laws.

mold boys" or "carrying-in boys

carry hot bottles to the annealing ovens (lehrs) or to open and close molds

30,000

The Owens machine could produce ______ bottles in 24 hours

wall-thickness inconsistency.

A primary limitation of mouth-blown glass was _________

(areas where the glass was dangerously fragile

"thin spots"

excessive weight that increased shipping costs

heavy bottoms

Contour Bottle

For Coca Cola, the 1915 introduction of the "_____" created a physical trademark. Uniformity ensured that a consumer in New York received the exact same experience as one in Georgia, cementing brand reliability.

Silica Sand
Soda Ash (sodium carbonate)
Limestone (calcium carbonate)
Alumina (aluminum oxide)

Sources of Glass:

Silica Sand (silicone oxide)

primarily sourced from silica sand, is the foundational raw material in glass manufacturing, constituting 70-75% of the formulation for common soda lime glass. It provides an amorphous, transparent, and durable network structure, with high-purity quartz essential for specialized optical or high temperature glass.

Soda Ash (sodium carbonate)

in glass manufacturing it acts primarily as a flux to significantly lower the melting point of silica (sand) from over to manageable temperatures. It enables the production of common soda-lime glass by enhancing energy efficiency, improving flow, and forming a workable melt. Commonly known as soda ash and washing soda

Limestone (calcium carbonate)

- acts as a crucial stabilizer in glass manufacturing to increase durability, chemical resistance, and mechanical strength. It introduces calcium oxide to the mixture, which reduces the melting point of silica. It also improves the stability of glass and prevents it from dissolving in water.

Alumina (aluminum oxide)

is a vital raw material in glass manufacturing that enhances chemical durability, strength, and thermal resistance. It is widely used in producing specialized glasses like fiberglass.

1. Inert to most chemicals

2. Impart no odour and taste to product.

3. Impermeability is important for long-term storage of products sensitive to volatile loss or oxidation by atmospheric oxygen.

4. Clear

5. Perceived as having upscale image

6. Rigidity of glass means shapes and volumes do not change under vacuum or pressure. 7. Stable at high temperature, making it suitable for hot-fill and retortable products.

Advantages of Glass Packaging

a. Fragile

b. Cracks when subjected to sudden change in temperature.

c. Expensive compared to other packaging material.

d. Transportation cost is high because of its heavy weight.

e. Less pressure safety and impact resistance.

f. Special Care and protection are required.

Disadvantages of Glass Packaging

Mixing & Melting

Manufacturing Process

Mixing & Melting

- - It is where raw materials are melted in a furnace. A feeder then delivers a "gob" of molten glass to the forming machine.

Mixing of all raw materials such as the silica, soda ash and limestones are placed in the mixing then into the furnace which is over 1000 deg Celsius. Molten glass “gob are now transported to molds ready for molding.

Shaping/ molding process

It is where raw materials are melted in a furnace. A feeder then delivers a "gob" of molten glass to the forming machine.

Blow and Blow
Wide Mouth Press and Blow
Narrow Neck Press and Blow:

3 types of Forming Processes:

Blow and Blow

Used primarily for narrow-neck containers.
is a fundamental technique in glass manufacturing, specifically designed for creating containers with narrow openings, like beer bottles, soda bottles,

Versatility in Design: It is the industry standard for any bottle where the neck is significantly narrower than the body.

Reduced Surface Friction: Because a metal plunger doesn't enter the body of the parison, there is less risk of internal surface defects or "chill marks" from cold metal contact.

Blow and Blow advantages

Wide Mouth Press and Blow

Specifically for wide-mouth jars.

A molten gob drops into the blank mold. A large metal plunger is pressed into the glass, forcing it to fill the mold and the neck finish simultaneously. This creates a very well-defined parison

The wall thickness is extremely uniform.

Wide Mouth Press and Blow key advantage

Narrow Neck Press and Blow:

A process used for lightweighting and high-precision narrow-neck bottles.

It is a more advanced evolution of the traditional "Blow and Blow" method. The key difference is that instead of using compressed air to form the initial cavity, a metal plunger is used to physically press the glass.

a. Lightweighting: Because the wall thickness is so uniform, manufacturers can use less glass to achieve the same strength.

b. Consistency: The internal diameter of the neck is extremely precise.

c. Faster Production: Better heat distribution allows the glass to cool more predictably, speeding up the machine cycle.

Narrow Neck Press and Blow advantgaes

Annealing

After forming, containers pass through a lehr for controlled cooling to prevent internal stress and breakage. If a freshly blown glass bottle is set on a table to cool at room temperature, it would likely shatter within minutes.

This is because glass is a poor conductor of heat; the outside would cool and shrink rapidly while the inside remained molten and expanded. This tug-of-war creates massive internal residual stress.

Hot End Coating (HEC):

A coating applied before annealing, this thin layer (e.g., tin oxide) increases the adhesion of subsequent coatings and strengthens the glass.

Lehr

is a long, continuous tunnel kiln equipped with a conveyor belt that moves the glass through precisely controlled temperature zones.

540°C to 570°C

Annealing Point Temp (roughly _________ for standard soda-lime glass) At this temperature, the glass is still solid but just "soft" enough for internal atoms to rearrange and dump their stress.

Soaking (Holding) Zone

The glass is held at this constant temperature for a set period. This ensures the temperature is uniform throughout the entire thickness of the glass— from the thick base to the thin neck.

Controlled Cooling Zone

This is the most critical stage. The temperature is lowered very slowly. If cooled too fast during this window, new stresses will be "frozen" into the glass.

Strain Point

the temperature below which glass no longer undergoes structural relaxation

Polariscope

To verify that the Lehr is doing its job, quality control technicians use a _________.

When viewed through polarized light, stressed glass shows "ghostly" rainbow patterns. A perfectly annealed bottle will appear dark or uniform, indicating that the internal molecular "tension" has been erased.

Flint

Basic Clear Glass. Used in majority of packaging applications.

Amber

Brown glass. Known to filter out light in the critical ultraviolet (UV) region. Iron and sulfur for brown color

Emerald

Bright green glass used mostly for wines and lime or lemon flavored soft drinks. Chrome Oxide is used to make glass it’s green color.

Blue glass

Cobalt oxides give glass it’s blue color

GLASS PACKAGING ANATOMY

Sealing Surface

The flat, circular top surface of the finish which makes direct contact with the closure to form a seal. It’s sometimes referred to as the “land.” If the sealing surface is not flat, the container could leak.

Thread

A spiral-shaped ridge on the finish of a bottle intended to mesh with a similarly sized screw-type closure to seal the container.

Neck Ring or Transfer Bead

A horizontal ridge at the base of the finish used for transferring the bottle from one part of the production process to the next

Mold Seam

The slight vertical ridge that runs through the neck ring and the rest of the finish. The seam indicates where two halves of the finish molds were joined.

Body

The main part of the bottle where the sidewalls are usually (but not always) vertical.

Bottom

The entire lower part of the bottle below the sidewalls. The bottom includes the heel, base and pushup. The bottom may have letters and symbols molded into it that indicate the number of the mold cavity that produced the container and the manufacturer. The manufacturer symbol is called a “punt mark”

Heel

The lower part of the bottle where the body (sidewall) turns from vertical to horizontal. The heel joins the sidewall to the bottom-bearing surface and may have a small recessed spot that serves as a registration device for labeling and decorating equipment.

Pushup

An inward dome in the center of the base. The resulting ring around the outside of the bottom ensures stability, providing an even bearing surface upon which the bottle rests

Finish

The top part of the container, above the neck, shaped to accommodate a specific closure. Historically, the finish was made during the last part of the bottle molding process, which is how it got its name

Neck

The portion of the container that is above the shoulder and below the finish. The neck is where the cross-section of the bottle grows smaller to join the finish

Shoulder

The part of the bottle that joins the wide main body and the narrower neck. The slope of the shoulder is one factor in determining how quickly a product will be dispensed when the bottle is inverted

Label Panel

A flat area on the body of the bottle that can accept the application of a label. Label panels are sometimes recessed to protect the labels from rubbing together during shipping and the edges from fraying.

Mold Parting Line

The bottom plate is the part of the mold that shapes the bottom of the container. The parting line is a slight horizontal ridge formed in the joint between two parts of the mold

Base

An even bearing surface that forms a ring around the outside of the bottom upon which the bottle rests. On glass containers, this ring usually is given a stippled finish in the mold to mask scratches that occur during handling

“T” Dimension

NECK FINISH DIMENSIONS: measures the outside diameter of the thread. This measurement determines the closure counterpart for the bottle

“E” Dimension

measures the outside diameter of the neck. The thread depth is determined by the difference between “E” and “T” divided by two

“I” Dimension

measures the inner diameter of the bottle neck. are required at the very minimum for sufficient clearance for filling tubes. Linerless closures with a plug or land seal and dispensing plugs and fitments require a controlled dimension for proper fit.

“S” Dimension

measures from the top of the finish to the top edge of the first thread. This measurement is the key factor to determine the orientation of the closure and the amount of thread engagement between the bottle and the cap.

“H” Dimension

the height of the neck finish. This is measured from the top of the neck to the point where the diameter “T” (the outside diameter of the thread) extends down to where it intersects with the shoulder.

Thread finishes

DBJ neck finish

is a tamper-evident screw cap for dairy, beverage, and juice. This neck features a ring beneath the threads that catch on to a detachable ring of a DBJ cap. When the user unscrews the cap from the container for the first time, the ring will break off from the cap, making it tamper-evident. This closure is not recommended for carbonated products, hot-fill applications, nitrogen gas-injected applications, or freezing.

Narrow Neck Containers:
Wide Mouth Containers
Form Variations

General Types of Glass Packaging

Narrow Neck Containers

Includes bottles for beverages like beer or spirits, often using crown cork or cork seals.

Wide Mouth Containers

Includes jars for the food industry, typically using thread, lug, or side-sealing systems.

Top Sealing
Side Sealing
Cork Sealing

Types of Sealing System

Crown Cork

The sealing surface is on the top of the finish and used for narrow neck containers being filled under pressure

Thread or Lug

The sealing surface on the top of the finish is closed by a screw type cap. Used for wide mouth jars and narrow neck bottles

Side Sealing

The sealing surface is on the side of the finish, and the cap is pressed on to seal the contents. It is used for wide mouth jars in the food industry

Cork Sealing

The seal is made on the inside of the finish. It is used with narrow neck bottles.

Economy Rounds

are very common in the marketplace. They have a wide mouth (opening) and are perfect for sauces. They are the classic mayonnaise jar.

Paragon Jars

are tall and lean. Commonly seen storing olives or other types of pickled products as well has jam and jelly preserves.

Boston Round Bottle (Winchester Bottle)

This heavy and strong bottle is very commonly used for chemical applications but is also used in food and cosmetic industries as well

Long Necked Bottles

These bottles come in a variety of sizes but the most common woozy bottle sighting for me is the intrepid hot sauce or cocktail bitters.

Wine Bottles

These usually come clear for white wines and tinted for red wines

Ampoules

is a tiny single dosage vial with a sealed neck

CAPACITY
VISUAL

Methods of Checking Dimensions

capacity

-The most important single property of a container is its _____. U

nit of measure is usually in metric units (ml or L)

The ____ is defined as brimful or state filling height.

Johnnie Walker’s 180g bottle

The world’s lightest whisky bottle.