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Method for preventing moldy glass and mildew of glass

2018-12-10

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  Method for preventing moldy glass and mildew of glass

  I.Overview

  In the process of preparing glass products by the traditional melting method,in order to reduce the cost,soda ash is selected as the flux,which is accompanied by the easy weathering of the glass products under certain conditions(commonly known as mold).Glass moldy(also known as anti-alkali)is a chemical reaction caused by excessive storage of glass or wet weather;rainbow,mildew,watermark,mime,paper,etc.appear on the surface under the sunlight.

  Moldy glass is a problem that occurs during storage and transportation.After the mold,the surface of the glass product will lose its luster,lose its transparency,and appear rainbow,white spots or patches(not easy to separate).

  Glass mold usually occurs on the air surface(top)of the float glass.This is because the lower surface of the float glass is in contact with the tin liquid,and a thin layer of tin is infiltrated into the surface to protect the glass.

  Second,the mold of glass can be divided into the following stages:

  1.Initially,water or moisture is adsorbed on the glass surface.

  2.Subsequently,water or moisture diffuses into the glass.

  3.The soluble silicate in the surface layer is hydrolyzed and destroyed.First,sodium silicate and potassium silicate are hydrolyzed and destroyed.Caustic soda(NaOH)is formed and SiO2 is separated.

  4.The separated SiO2 forms a silicone gel which forms a protective film on the surface of the glass which prevents further erosion.

  5.The caustic soda formed by hydrolysis reacts with carbon dioxide in the air to form sodium carbonate,which accumulates on the surface of the glass to form a soluble salt in the surface film.Due to its strong hygroscopicity,it absorbs moisture and deliquesces,eventually forming lye droplets.As the surrounding temperature and humidity change,the concentration of these droplets also changes.If the concentrated lye droplets are in contact with the glass for a long period of time,the gel-like silicone film can be partially dissolved therein,causing severe local erosion of the glass surface to form spots.This is a group of white alkali-rich ions that are formed by the migration of sodium ions from the glass body and reacting with air.A white particle swarm can be observed by scanning electron microscopy.

  Third,moldy identification and inspection methods

  Visual appearance of the topography is the most succinct and feasible method.The specimen was placed in reflected light and transmitted light to observe the presence or absence of spots and mist on the surface of the glass under concentrated light.These spots and mists cannot be wiped off with cloth or water.The glass in which the above phenomenon occurs indicates that the sample has been moldy.If concentrated glare is observed,a small number of spots and mists are slightly mildewed by the naked eye.If concentrated glare is observed,many spots and light mists are observed by the naked eye.If there is no concentrated beam of light,some spots and fog are observed by the naked eye to be severely moldy.

  Moldy can also be observed by spray wetting under natural light.

  Fourth,mold prevention

  On the one hand,it is related to the surface characteristics of the glass itself,and also closely related to the anti-mold treatment measures,the degree of packaging sealing,and the storage and transportation conditions taken before the float glass packaging.When the float glass is formed and annealed,it is generally packaged in-line,and the temperature of the glass is about 50 to 100°C.The packaged glass must be in stock and shipped to the user,sometimes for a long time.If you encounter high temperature,high humidity season,improper storage and transportation,moldy glass will appear mold.

  Moldy appears on the air side of float glass because the tin side(lower surface)of the glass is because 12345678

  Mechanism of glass self-defect,original film packaging

  Moldy process P45

  At room temperature or slightly above room temperature,the fresh glass surface will absorb moisture and grease from the surrounding environment,and the OH-based form of the adsorbed water combines with Si4+to affect the structure of the glass surface.

  Since OH-ions can form hydrogen chains and adsorb other substances,the cleaned glass surface can be rendered hydrophilic by water,ethanol or sulfuric acid surfaces,but becomes hydrophobic due to the attachment of other substances.

  The surface of the glass has the following characteristics:1 during the annealing process,the alkali ions move to the surface of the glass;2 the surface is easy to react with O2,SO2,H2O and HCL;3 the surface strength is low,and the Griffith crack is easy to occur;4 is easy on the glass surface.Ion exchange;glassy Sio2 on the surface of 5 can be hydrolyzed to break the Si-O bond;6 surface components are easy to evaporate and decompose;7 surface is easy to devitrify;8 surface has temperature and the like.

  Surface defects of glass:

  1 There are micropores or voids on the glass surface

  It is mainly formed by the volatilization of the surface composition.Due to the volatilization of the alkali,the surface is formed on the surface,and the upper surface of the float glass has more protrusions and depressions than the lower surface(tin surface).The porosity of the glass surface allows the glass to facilitate ion exchange on the surface and allows the surface to easily react with O2,SO2,H2O,HCL,and the like.Therefore,the upper surface of the float glass is prone to mold,and it is easy to perform surface coloring or the like.

  2 There are cracks on the glass surface:

  These cracks are not mechanical damage,but are related to the internal structure:low surface strength,easy to produce Griffith cracks.

  3 moldy during storage and transportation:

  Silicate glass

  Moldy glass occurs mainly during storage or transportation after packaging,which is related to packaging,storage and transportation.

  The package can be packaged in a hot state or in a cold state with paper or mildewproof powder.

  1 is usually stored in a well-ventilated warehouse;

  2 Do not allow the glass box to be placed directly on the damp floor in the warehouse;

  3 It is not allowed to store glass outdoors and under direct sunlight.

  Five:moldy glass treatment

  Glass mold remover is a glass treatment solution newly developed by our company.

  ★★★玻璃救星★★★一号(glass mold remover)

  [Scope of application]Applicable to all mild mildewed glass products(such as colored red,mildew,water on the glass after edging)

  [Usage]Use a cleaning cloth or sponge to rub a little of this product in the moldy area ofthe glass,then rinse it off with water,so that the moldy product can be renewed to get your satisfactory results.

  This product has no impact on people and the environment.It is the most ideal and environmentally friendly product on the market,and the simple operation is the most ideal and most affordable choice for individuals and businesses.

  ●●●Glass savior●●●No.2(to paper pulp)

  [Scope of application]Applicable to glass products with long-lasting mold,paper grain and paper printing

  [Usage]Put the glass into the original solution for 5-8 minutes,then rinse it with water.The effect is as clean as new.This product has no effect on people and environmental protection.It is an environmentally friendly series on the market.

  ◆◆◆This product is used as an ordinary(glass cleaner):

  [Scope of application]Efficient and rapid cleaning of the glass,without the need for water,leaving no traces,can restore the glass surface to crystal clear,can also be used for bathroom equipment,tiles,mirrors,stainless steel and so on.

  [Instructions]

  1.Spray the product 1:20 with water and spray it on the glass counter with a watering can.The surface of the glass exterior wall should be used with a soft cloth or glass scraper.

  2.If you need to clean the surface with granular dirt,you need to wash it off or shovel it off,then use a soft cloth or glass scraper to avoid scratching the surface.

  3.This product is suitable for computer,fluorescent screen,need to be diluted with water(1:10)