Laundry training manual
First, Overview of the Laundry
Laundry's main function is responsible for all the needs of the hotel within the washing of linen for regular washing, sorting, and release. The washing process principle is the most reasonable cost for accessing to clean, clean fabric.
1. the object and purpose of washing
Effectively getting rid of stains on the fabric and maintaining the original appearance and feeling of fabric, thus, reducing damage and extending its using life.
2. the Department of laundry workflow:
(1) collection and transportation
(2) check and categories washing items
(3) treatment of washing detergent
(4) ironing and drying
(5) collating, folding and delivery
Second, five basic elements of impacting the washing
1. Mechanical force: the rotation of washing machine drum produces mechanical force, and pound of washing liquid as well as friction between the washing fabrics. Under a variety of strengths, the relative motion between the fabric and washing liquid is accelerated, thus, the dirt from the fabric quickly spread into washing fluid. The loading weight of washing machine is the major factor impacts function of washing machine ability. Standard washing Loading: 80％ capacity of washing machines.
2. The water level: in different stages of washing process, the appropriate washing water level should be selected. The water level would affect not only the level of concentration lotion, but also can affect the mechanical force.
3. Time: washing is a physical and chemical reactive process that requires the appropriate role of the time. Washing time has relation with the structure of fabric, type of dirt and level of pollution. Capacity of washing machine is decided by the size, type and level of detergent, which all have impact on washing time.
4. Temperature: In the washing process, the temperature has played a catalytic role. With the increase of temperature and speed up the dissolution of the detergent, the movement of elements speeds up and capability of penetrative decontamination is improved. The formulation of temperature is line with fabric texture, color fastness and type of dirt and usage of detergent.
5. Washing procedures: According to the structure of fabric, characteristics of stains and level of pollution, suitable washing procedures should be choose so that achieve the best washing.
In addition to above five elements, water is also an important factor impacting washing effect. In the process of washing, water as a media soluble the detergent and consist a certain concentration, under a certain time, certain temperature and mechanical force, to remove the decontamination of polluted fabric. Therefore, in addition to understand the five elements, water in the influence of washing should also be concerted.
Water has a wide range of application. In the process of washing, it’s characteristics of strong dissolvability, power of dispersion, unburying, non-toxic, tasteless and cheap. However, it cannot dissolve oil, has strange surface tension and metal salts. Too much involvement of metal salts in the water would seriously affect washing effect, resulting in a yellow fabric, hair gray, black and poor feeling of the fabric; In the meanwhile excessive iron have a certain reaction on catalyst so strong that would lead to fabric partially damaged. Standard of water washing is generally pH: 7.5 ~ 8.0 with hardness of below 3 degrees (Germany-hardness units: DH 10mg / L to a degree) and the content of iron is no more than 0.1 mg / L.
Adsorption on the surface and internal of fabric, then changing the surface appearance, texture of the fabric material. It exists in fabric the following two ways:
(1) Physical adsorption:
Adhesion of this kind such as soot, dust, sand and carbon black are all physical adsorption. This role relatively weak, easily removed. Adhesion is divided into physical mechanical adhesion - this type of adhesion mainly refers to the number of solid dirt such as dust, sand. Mechanical adhesion of dirt is a weak adhesive, which can be removed almost purely by mechanical method.
(2) Adhesion static electricity - this type of adhesion mainly live in the dirt particles in the opposite charge of objects. Electrostatic role than a simple mechanical stronger role, thus removing the dirt is relatively difficult.
(3) Chemical adsorption:
Through chemical bond take effect on dirt such as protein, rust on fabric. This kind of dirt on the fabric is so strong that special method should be needed. There are many types as following:
1, Water-soluble Dirt: do not have to add detergent and only water can remove the basic dirt such as fresh blood, urine sewage, waste grain of rice, dirt, etc.
2, alkali-soluble dirt: Take alkaline detergent to remove the dirt such as some animal and plant oil pollution, dirt fatty acids and starch dirt.
3, dirt of oxidation: that means in washing process, dirt has not been fully removed, then removed by oxidant effect, such as beverage stains, grass scale, the scale of tea, soy sauce and natural fuel.
4, acid dirt: through the acid treatment, the dirt will be able to remove (such as rust).
5, selective dirt: the dirt can be dissolved solvent (mineral oil, paint dirt, paints the dirt, etc.).
6, insoluble dirt: dirt that is dissolvable in water, organic solvent and need to use surfactants that scatter dirt particles, which dissolved in water so to achieve the objective of removing dirt (dust, soot, coal Ash, mud, cement, etc.).