Take you to understand glass bottles and their craftsmanship

Glass bottles are generally formed by blowing and pressure blowing. The blowing method is generally suitable for narrow-mouth bottles, like water-emulsion type bottles, and the pressure-blowing method is generally suitable for wide-mouth bottles, such as cream bottles. shape.

The process of glass bottle products is also called deep processing of glass bottles, which refers to deep processing on the surface or inner wall of glass bottles, such as frosting, silk screen printing, bronzing, spraying, electroplating, polishing, etc., so that the surface of glass bottles presents different technological effects.

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Frosting process

Principle: SiO2+4HF=SiF4+4H2O

Chemical frosted glass is essentially a matte acid-etched glass, which is similar in principle to chemical etching and chemical polishing, both of which use acid to chemically corrode the glass surface.

People can not only frost the overall surface of glass products, but also make partial frosting of glass products to form patterns. The frosting process of pattern patterns is usually called rough surface etching.

Chemical polishing: It is to prevent some insoluble reactants produced by chemical corrosion of acid and glass from adhering to the glass surface, and try to dissolve and rinse them off. The chemical polishing process is always a process of uniform erosion of the entire surface, so as to obtain a transparent and smooth surface;

Chemical frosting: The insoluble substances that have not been removed from the chemical reaction adhere to the surface of the glass. With the continuation of the reaction time, the reactants accumulate into granular crystals (fluorosilicate crystals), which are firmly attached to the surface, and the reactants adhere to the surface. The surface of the surface hinders the further reaction of the acid etching, that is, it becomes a non-uniform erosion, and a translucent rough surface is obtained, which scatters the incident light and is translucent with a hazy feeling, so it is called frosting.

Frosting material

The chemical frosting materials on the market mainly include the following: hydrofluoric acid, frosting paste, and frosting powder.

If the proportion of hydrofluoric acid is good, the effect is ok, and the time required for frosting is shorter than that of frosting paste and frosting powder. However, hydrofluoric acid is not suitable for mass production, especially when the weather is hot, its operation is relatively unstable, and it is easy to volatilize in the air and cause pollution to the atmosphere. Moreover, hydrofluoric acid is also very harmful to the human body. It can corrode the appearance and bones of the human body. It is a frosting method that is gradually eliminated.

Take you to understand glass bottles and their craftsmanship08Frosting paste is mostly suitable for local frosting of glass products, and the operation is more convenient; but frosting paste is not suitable for large-area glass frosting, the main reason is that when it is used for large-area glass frosting, it is easy to produce frosting Surface unevenness, etc. Frosting paste is often used in screen printing.

Compared with frosting paste, frosting powder has a slightly more complicated operation process, that is, frosting powder needs to be formulated into a solution. However, frosting with frosting powder is suitable for almost all glass products. It can not only frost glass products such as glass cups, glass bottles, glass lamps, etc. that can be immersed in the solution; it can also frost flat glass, sliding door glass, etc. Glass products are frosted.

Main chemical components of frosting powder: fluoride, ammonium sulfate, barium sulfate, potassium sulfate and other additives

Note: Usually fluoride (such as ammonium fluoride, potassium hydrogen fluoride, calcium fluoride) is used as the main component, and then ammonium sulfate, barium sulfate, potassium sulfate and other additives are added to prepare frosting powder. When using, add sulfuric acid or hydrochloric acid to prepare a frosting liquid. The glass products are placed in this frosting liquid, and the hydrofluoric acid generated by the reaction between the frosting powder and the acid will erode the glass products to achieve the frosting effect.

Frosting paste and frosting powder are relatively safe and easy-to-operate frosting materials, which are suitable for different processing requirements. Frosting paste is mostly used for partial frosting of glass, which can create a beautiful frosting pattern effect, while frosting powder is suitable for sanding a large area of glass. The two are complementary according to the needs of use.

Recipe: (calculate the required material with 1 kg of frosted powder frosted glass 1 square meter as the standard).
Frosting liquid Frosting powder: concentrated hydrochloric acid = 2:1
Pickling solution Sulfuric acid: water = 5: 100

Frosting method

  • Immersion method: immerse glass products in frosting liquid for a certain period of time
  • Blowing method: spray the frosting liquid onto the glass surface
  • Coating method: apply frosting paste on the surface of glass products

Frosting process:

Pickling (cleaning the glass surface) → frosting (about 45 seconds) → pickling (cleaning the frosting liquid on the glass surface) → water washing (cleaning all the frosting liquid) → drying (wind or other method to dry the frosted glass)

The difference between frosted glass and sandblasted frosted

Sandblasted glass: It is to hit the glass surface with high-speed sprayed glass sand particles, forming a fine bump on the glass surface, producing a hazy effect so as to achieve the effect of refraction of light. The finer the glass sand, the finer the particles. The effect is high three-dimensional. [Usage: The sandblasted glass has large particles, which is easy to accumulate dust and blacken for a long time and is not easy to clean. It is the initial glass treatment process. Generally used for large-area glass processing such as construction, decoration, bathroom doors and windows]. Compared with frosting, the surface of the glass products of the sandblasting process is relatively rough, the breakage rate is high, the dust pollution is large, and the process difficulty is average.

Frosted glass: After the ordinary glass bottle is frosted with frosting powder, it is a frosted glass bottle. The production process of corroding its surface by soaking with chemicals is mainly used for screen printing and can be painted on the glass surface. Frosted glass feels delicate, durable and easy to clean. The price and processing cost are higher than those of sanded glass. If it is polished again, it will feel softer, no fingerprint effect and stronger light transmission. It is also called jade sand glass.

Frosted glass: also known as frosted glass bottle, dark glass bottle, is a general term for sandblasted glass and frosted glass. It is made of ordinary flat glass by mechanical sandblasting, manual grinding or hydrofluoric acid dissolution and other methods to treat the surface into a uniform surface. Due to the rough surface, the light is diffusely reflected, and the light is transparent without perspective. The frosted glass bottle can make the light soft and not dazzling. Glass that is too thin is not suitable for frosting.

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Frosting FAQ

Uneven frosting: The surface reason is that the corrosion depth is different, the thickness of the sand surface is uneven, and the reason behind it is that the frosting liquid is uneven. The solution: add hydrochloric acid and hydrofluoric acid in proportion to accelerate the aging and dissolution of the frosting liquid. Add old frosting fluid to neutralize the strength.

Light transmission: caused by foreign objects on the bottle body / caused by frosting liquid / caused by pickling. Oil stain on the bottle body: After frosting, there is generally a large area of ​​regular translucent light. In the frosting process, the place without oil stain first reacts with the frosting liquid, while the place with oil stain is first decomposed by hydrofluoric acid and then with the frosting. Liquid reaction, that is, the reaction time of the two places is different from that of the frosting liquid, and what you see is regular translucent. Solution: Pickling, mainly divided into two methods according to the severity of oil pollution: mild, pickling pretreatment acid ratio is generally 7% hydrofluoric acid, 5% hydrochloric acid, and 88% water. Severe, pickling pretreatment acid ratio of 12% hydrofluoric acid, 5% hydrochloric acid, 85% water, and then add a water washing tank.

Silkscreen

Take you to understand glass bottles and their craftsmanship02High-temperature screen printing and low-temperature screen printing are commonly used in screen printing.

Low-temperature silk-screen printing is that the ink is oily, and after printing, it is baked at a low temperature of about 150 degrees; some silk-screen printing does not need to be baked, and is left to dry naturally after printing; the advantage is that the color is diversified, the ink is stable, and the color difference is small. It is more difficult to design, such as network lines or thin text, which can achieve better printing results, but the disadvantage is that the ink is not strong enough, and it is easy to scratch and touch the flowers;

High-temperature silk screen printing is that the ink is in the form of powder. After printing, it needs to be baked at a high temperature of 550-700 degrees. Its advantages are friction resistance, not easy to fade, strong adhesion, bright colors, and bright colors. Color difference, some colors cannot be done well in high temperature silk screen printing, such as purple, which cannot be well displayed for too thin text and lines;

Glass bottle hot stamping

Hot stamping is to use hot stamping paper to press the product at a high temperature of 200 degrees when the low-temperature screen printing ink is not dry. Press each other in a short period of time, and transfer the metal foil or pigment foil to the surface of the hot-printed product according to the graphic of the hot-stamping stencil. For some high-end products, customers will bronze the trademark or brand logo on the product. Gold and silver are the main colors, and other colors of bronzing products can also be produced, but due to the limitation of raw materials, color matching cannot be carried out.

Glass bottle spraying

Spray on the surface of the product and spray a uniform water-based paint coating with an air gun. After the sprayed product is leveled, preheated and dried, the coating is cured, which plays a decorative and protective role on the glass bottle; the spraying of various spraying effects makes The appearance of the product is improved;

A layer of organic paint is attached to the surface of the glass bottle (the glass paint is added with specified colors, additives, etc.), so as to achieve the requirements of rich colors on the glass bottle, which can achieve high gloss, matte, pearlescent, transparent, gradient, etc. effect product.

Spraying process:

Bottle loading → bottle cleaning → flame treatment → electrostatic dust removal → spraying → preheating → curing → cooling → bottle loading → packaging

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Glass bottle electroplating

Take you to understand glass bottles and their craftsmanship04Two common electroplating processes: water electroplating and vacuum ion plating, generally vacuum ion plating is used

Vacuum plating is a physical deposition phenomenon. That is, argon gas is injected in a vacuum state, and the argon gas hits the target material, and the target material is separated into molecules that are adsorbed by conductive goods to form a uniform and smooth surface layer.

The main idea of vacuum plating is divided into two types: evaporation and sputtering.

Electroplating is carried out in the electroplating pool, sputtering is under high voltage, evaporation is evaporated at high temperature, and the aluminum in the disc is sputtered.

Vacuum electroplating can produce a black effect with good gloss that cannot be achieved by ordinary electroplating.

The PC material has a temperature resistance of 130 °C, and only “vacuum plating + UV oil light curing” can meet the high temperature resistance requirement of 130 °C. The general water electroplating is unable to electroplate the PC material.

Vacuum plating mainly includes several types of vacuum evaporation, vacuum sputtering and vacuum ion plating.

Vacuum ion plating, also known as vacuum coating. The practice of vacuum plating is a relatively popular practice, and the products made have a strong sense of metal and high brightness. Compared with other coating methods, the cost is low and the pollution to the environment is small, which is widely used in various industries.

Vacuum ion plating: The technical principle is as follows: the vacuum arc discharge technology is used in the vacuum chamber to generate arc light on the surface of the cathode material, so that the cathode material evaporates to form atoms and ions. Under the action of an electric field, a beam of atoms and ions bombards the surface of the workpiece as an anode at high speed. At the same time, the reaction gas is introduced into the vacuum chamber, and a coating layer with excellent performance can be formed on the surface of the workpiece. Cathode materials (also known as target materials) generally use metals such as titanium, chromium, and zirconium, and commonly used reactive gases are nitrogen and hydrocarbon gases. The obtained coatings include TiN, CrN, TiC, ZrN and the like.

Vacuum ion plating technology has the following advantages:

(1) High hardness coating can be obtained, the coating has a small friction coefficient and high wear resistance.
(2) The coating has good chemical stability, high temperature oxidation resistance and good corrosion resistance.
(3) The coating is beautiful. Gold shades such as 18K gold and other colored films are available.
(4) The bonding force between the coating and the substrate is high. Its bonding force is higher than that of traditional magnetron sputtering, vacuum evaporation and other coatings, and the coating is not easy to peel off.
(5) The production process does not pollute the environment. The coating formation speed is fast, saving electricity and water.

Vacuum coating refers to a method of heating metal or non-metallic materials under high vacuum to evaporate and condense on the surface of the plated part (metal, semiconductor or insulator) to form a thin film. For example, vacuum aluminum plating, vacuum chrome plating, etc.

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Vacuum electroplating can be divided into: general vacuum electroplating, UV vacuum electroplating. The special processes of vacuum electroplating include evaporation, sputtering, gun color, etc.

Vacuum evaporation: referred to as evaporation, refers to the use of a certain heating evaporation method (tungsten wire) to evaporate the coating material (or film material) under vacuum conditions and vaporize it, and the particles fly to the surface of the substrate to condense to form a film. process method. Evaporation is an early and widely used vapor deposition technology, which has the advantages of simple film formation method, high film purity and compactness, unique film structure and performance.

Vacuum sputtering: In a vacuum environment, an appropriate inert gas is introduced as a medium, and the target is accelerated by the inert gas, so that the atoms on the surface of the target are knocked out and a coating is formed on the surface.

Sputtering, usually referred to as magnetron sputtering, is a high-speed low-temperature sputtering method. The process requires a vacuum degree of about 1×10-3Torr, that is, a vacuum state of 1.3×10-3Pa is filled with inert gas argon (Ar), and is added between the plastic substrate (anode) and the metal target (cathode). When the high voltage direct current is applied, the electrons generated by the glow discharge excite the inert gas to generate plasma, and the plasma blasts the atoms of the metal target material and deposits them on the plastic substrate.

Sputtering is to bombard the surface of the material with charged particles with a kinetic energy of tens of electron volts or higher, so that it sputters out into the gas phase, which can be used for etching and coating.

The coating principle of sputtering and ion plating is different.

Vacuum evaporation uses resistance (tungsten wire), electron beam, laser and other methods to heat the film material to evaporate or sublime the film material.

Resistance heating source is a commonly used evaporation source, which is simple in structure and easy to operate.

Vacuum evaporation method is a method of heating metal under high vacuum conditions, melting and evaporating it, and forming a metal film on the surface of plastic after cooling. Commonly used metals are low melting point metals such as aluminum.

Vacuum evaporation can theoretically coat these low melting point metals (aluminum, nickel, zinc, copper, silver, gold). However, considering the cost, only aluminum and nickel are generally plated.

The metal to be plated and the plastic product to be plated are placed in a vacuum chamber, and the material to be plated is heated by a certain method, so that the metal evaporates or sublimates, and the metal vapor condenses into a metal film when it encounters the surface of the cold plastic product.

Generally, vacuum evaporation requires the pressure in the film forming chamber to be equal to or lower than 10-2Pa. For occasions where the quality of the evaporation source, the product to be plated and the film is very high, the pressure is required to be lower (10-5Pa).

When evaporating plastic products, it is necessary to adjust the evaporation time in order to ensure that the heat emitted when the metal cools does not deform the resin. In addition, metals or alloys with too high melting and boiling points are not suitable for vapor deposition.

The vacuum evaporation process generally includes: substrate surface cleaning, preparation before coating, evaporation, removal, post-plating treatment, detection, finished products and other steps.

Vacuum coating can coat a variety of plastics such as: ABS, PE, PP, PVC, PA, PC, PMMA, etc.


Post time: Nov-09-2022