Non-woven preparation There are two primary methods of assembling non-woven fabrics: the wet laid process and the dry laid process. 1 One dry laid process is the "meltblown" method, which is used to make non-woven fabrics from plastic resins. In this method, plastic pellets are melted and then extruded, or forced through tiny holes, by air pressure. As the stream of fibers cools, it condenses to form a sheet. Hot metal rollers are used to flatten the fibers and bond them together. 2 A wet laid process is typically used for softer cloths, like diaper wipes, that use cotton blends. In this wet process, the fibers are made into liquid slurries with water and other chemicals. The resultant paste is pressed into flat sheets by rollers and then dried to form long rolls of fabric. These rolls are then further processed and slit into narrow widths and then perforated or cut into individual sheets. The finished cloths are classified by their dry weight that is at least 1.4 oz/in2 (40 g/m2). Absorbency of the wipes is also an important requirement (quality wipes can absorb between 200% and 600% of their weight in solution). When manufacturing baby wipes, a wet laid process is typically applied. During this process, the non-woven fibers are made into liquid slurries with water and other chemicals, resulting in a paste which is then pressed into flat sheets by rollers and dried to form long master rolls of material. The master rolls are then further processed using a slitter rewinder, cutting the sheets down into smaller sizes for additional processing.

When the slitting process is complete, a pneumatic cross cutter traverses to cut the material in order to begin a new roll. Then, the master roll is discharged onto a platform preparing it for the next phase of manufacturing: consumer roll slitting and perforating.

Non-woven treatment 1 Onced prepared, the non-woven cloth is fed from storage rolls onto coating machinery, where the cleansing solution is applied. Several methods can be employed in this process. The cleansing solution can be added by running the fabric through a trough of the solution, or sheets of fabric may be sprayed with the formula from a series of nozzles. 2 Alternatively, individual towelettes may be packaged in sealed foil pouches. In this process, sheets of laminated foil are fed into automated equipment which folds them into a small pouch and heat seals three sides to form an open envelope. Simultaneously, another conveyor line feeds the non-woven cloths into the pouch. A liquid feed mechanism, including conduits extending through the stuffing bars, injects moisturizing liquid into the towelette packet simultaneously with the stuffing of the towelette material. The ingredients used in the wipe solution are prepared in large batch tanks. Depending on the formula requirements, the tank is charged with the first ingredient which is usually water. The tank may be heated during manufacturing to facilitate blending of powders that must be dissolved or other solids that must be melted. The other the ingredients are added sequentially and mixed until homogenous.

This next process takes the master rolls of non-woven material and slits them into various widths typically used for canister or bucket wipe products. Some consumer roll slitting and perforating machines (like those offered at Pinnacle Converting Equipment) are capable of increasing roll production capacity by unwinding, perforating, slitting, and rewinding wipes rolls at a rate of up to 60 per minute.

Once the non-woven cloth is prepared, it is then fed onto coating machinery, where it is coated in the cleansing solution before being packaged. The finished products are folded, stacked, and transferred to their final package.Immediately following this operation, another heat sealer closes the pouch tightly. The finished cloths are automatically folded, stacked, and transferred to their final package. In one patented method  the towelettes are folded and stacked so that they can easily be removed one at a time and then the stack is placed in an inner plastic pack. This inner pack is subsequently inserted into an outer tub with a hinged cover.

Quality Control Each component used in baby wipes must pass a series of quality check points during the manufacturing process. The plastic packaging must be free from mold defects that could cause leakage or improper closure. The non-woven fabric must be uniformly formed and must meet specific tear-strength requirements. Furthermore, prior to manufacture, the cleansing solution must be thoroughly tested. Development chemists evaluate the product to ensure that it is shelf stable and will not undergo any undesirable chemical reactions. They must also test the formula to ensure that it satisfies the requirements for mildness. The most reliable method used to test mildness is known as the Human Repeat Insult Patch Test (HRIPT). In this test an ingredient, or series of ingredients, is applied to human volunteers (usually on the inside of the forearm). The area is then occluded with a patch material and the spot is evaluated by dermatologists or clinicians after a specified time. Any redness or irritation is assigned numerical value and the scores of all the panelists are averaged. A low average score, such as 0 or 1, indicates that the product is essentially non-irritating. Before ingredients are added to the batch tank, they are assayed to ensure they conform to all relevant specifications. During manufacture, each ingredient is check weighed before it is added to the batch. Then final batch is tested again for basic specifications such as pH, viscosity, and microbial content.