Garment Pressing Technology

Pressing: Pressing is the application of heat, moisture and pressure to shape, mold or crease fabrics, garments or garment into the geometric form intended by their designers. Pressing may be done during assembly to facilitate other operations and improve quality or as final finishing process.

In-process pressing: It is also known as under pressing and used to crease, shape and smooth components for more accurate seaming. Sharp edges on garment components increase accuracy in sewing. Finish pressing: It is also known off pressing and adds the final shape to seams and the garments. Without finish pressing even the most well executed seams will not have a pleasing appearance.

The time, temperature, pressure and types of mechanical devices used for pressing depends on Types of material used The shape which is required in final garment The degree of permanency needed.

Elements of pressing: Heat: Heat is needed in most pressing processes to soften fibers, stabilize, and set the desired shape. Temperature must be selected to suit the fibers, yarns and fabric used. Steam: Steam is the fastest means to transfer heat into the fabric. Steam is created by heating water in pressure/boiler. The higher the pressure, the hotter and drier the steam. Effective use of steam reduces the time for pressing and amount of pressure required. Excessive moisture can cause shrinkage and color bleeding.

Pressure: Pressure is applied to alter the shape and increasing the permanency of creasing or molding. The amount and type of pressure needs depends on fabric characteristics and style. Too much pressure may distort cause fabric surface, flatten textures and may create permanent fabric or garment damage. Pressure may be applied by steam or mechanical device. Mechanical Pressure: Mechanical pressure require a combination of solid surfaces such as tables, bucks or irons to mold the garment. It is specified by the amount of force or pounds of pressure per unit time. Air or steam pressure: Air or steam is blown into the garment to expand it to its full size while the heat or steam are applied. Air or steam pressure is determined by the amount of the pressure at the point of contact with the garment over the time steam is applied.

Pressing Equipment: Solid surface pressing equipment uses a firm surface to apply the pressure while the steam and heat mold the fabric, garment or garment parts. Pressure may be applied through rolling action, gliding action or compression. Solid surface pressing equipment consists of buck presses, irons, blocks, dies, rollers, collapsible forms and creasing and folding blades.

Buck Presser: Buck presses are mostly used for slacks, skirts and jackets as well as by most dry cleaning plants. Buck pressing can be used for in process pressing and final pressing. Components of buck press include: A lower buck Complementary moveable head with linkage system Buck padding Steam and vacuum systems Frame and table Gauges Manual or automatic control for steam, vacuum, heat and pressure.

The actual pressing devices are a lower buck and complementary head that move in a scissor like pattern. Bucks vary in length, width and contour. The lower surface or bed buck is in fixed horizontal position to support the fabric or garment during pressing. The head is attached to the lower buck but is mobile. The head moves down when activated by the operator to cover the material as it rests on the bed buck. Steam is released and drawn through the garment by the vacuum system. When head is released it returns to an open position. Buck padding serves to distribute the steam evenly, reduces the impact of steam on fabric and provide a soft resilient surface for the fabric. Padding protect the fabric from shine due to high pressure and the hard surfaces. It also act to prevent uneven steam pressure or high ejection velocities which may cause steam spots on the fabric.

Buck Presser:

Iron pressing: It is manual molding operation in which pressure and heat are applied with a flat contact surface. The iron pressing work station consists of an iron, power line, bed buck and iron support system. In most cases pressing combination also contains a steam and vacuum system. Systems may be portable or stationary. The main difference between iron pressing and buck pressing is that the iron which serves as the head and the bed are not linked. Irons have flexible positioning which is responsibility of operators. Irons vary in weight and sole plate dimensions and characteristics depending on the type of pressing operation, fabric area to be pressed and quality specification of the operation.

Irons have support system to facilitate handling and reduce operator fatigue. Irons are used extensively for under pressing and are more versatile and mobile than other type of pressing units. Bed bucks used with iron pressing also vary in size, shape and contour. On side seams and inseams slack manufacturer may use long narrow curved bucks. This type of buck when used with iron facilitate busting of slacks.

Block or die pressing: It is a molding process that establishes a product’s conformance to a form. Block pressing may change the surface characteristics and dimensions of a product. The fabric is placed on a fixed die or block before pressure, heat or steam are applied. Block pressing may be used by gloves or hat manufacturer to shape and mold their products. Another form of automated die pressing is used to fold and crease patch pockets and pocket flaps. An operator position the component over a die and engage the machine and folding blades fold and hold the edges to the underside for creases to be set. This may be used with automated sewing to stitch the pockets in place. It is also used to shape and mold the collars, collar stands and cuffs.

Foam Pressing: Foam pressing equipment is used for the final pressing in garment production or for renovating garments in dry cleaning plants. Foam presser are made in approximate shape as final garment. The expandable/collapsible bags made in approximate form of the finished garment. Steam is forced from the inside of the foam through the garment while the foam expands to fill all the space inside the garment. This gives the garment final shape. Foam presser are designed to reduce the amount of positioning and repositioning time. The entire garment is pressed with one serge of steam. This type of presser smoothes fabric but does not set creases.

Foam Presser for Tee Shirt

Steamers: Steamers are the pressing machines that use only steam to mold and smooth garment. The major type of steamers are steam jet, steam guns, steam puffs, steam tunnels or chambers. Steam tunnel or chamber are used for finish pressing. Garments are dewrinkled within a chamber by the average pressure of the circulating steam. Some steam tunnel have drying chamber that use dry heat to extract moisture from garment before packaging. Boilers, steam generators and vacuum systems are essential parts of any pressing system as they generate the steam and air pressure that is required. The quantity of steam has a major impact on production cycle time and appearance of finished garments.

Technology advancement in pressing: Advancement in finishing technology focus on several areas. Greater versatility More precision in determining exact pressing requirements of fabrics and finishes Improved quality Energy savings

Greater Versatility: Greater versatility is needed to service the wide variety of fashion garments a manufacturer produces over an extended period of time. This may be accomplished with a variety of interchangeable bucks that are designed for specific garment shape. Microprocessors with a wide variety of setting can control factors such as conveyor speed, steam and air volume and temperatures. Computer determine settings and control the processing so that each garment can be treated in exact same manner. Carousel pressing combines several pressing operations that one operator can complete at one workstation with minimal handling and control.

Energy efficient technology: This includes things such as increasing the insulation to prevent the heat loss, self contained systems so the source of heat and steam is closer to the pressing unit and inclusion of vacuum systems to reduce the amount of heat and steam needed for effective pressing.

In some new pressing equipments the steam generator and pressing devices are included in a self contained unit that makes it portable in the plant. Automated buck presser control the amount of time, temperature and pressure for the steam application. The head releases automatically when the determined amount of time lapses. This guarantees equal exposure to steam and extraction for each garment. With manual operated presser the operator control the time of exposure.