CN101607787B - Preparation method of lead-free electronic glass - Google Patents

Abstract

The invention relates to a preparation method of lead-free electronic glass. Lead-free electronic glass is developed at home and abroad, and has a main systems comprising Bi2O3-B2O3-SiO2, Bi2O3-B2O3-ZnO, V2O5-B2O3-ZnO, BaO-B2O3-ZnO, and the like. The front three system raw materials have overhigh cost, and the cost of the materials is above 100 yuan per kilogram, and the expansion coefficient of the fourth material system is too large. If the expansion coefficient is to be lowered, a melting point of the materials is needed to rise. The lead-free electronic glass is prepared from the following raw materials by weight portion: 30 to 80 portions of B2O3, 10 to 30 portions of ZnO, 5 to 10 portions of Na2CO3, 1 to 10 portions of CaCO3 and 1 to 5 portions of feldspar. The lead-free electronic glass has excellent electrical performance, small dielectric constant, little medium loss as well as high volume resistivity and breakdown strength, and cannot generate damage to a human body during production or generate harmful waste gas, waste water and waste slag.

Description

Preparation method of lead-free electronic glass

Technical field

The invention belongs to technical field of electronic materials, relate to a kind of preparation method of lead-free electronic glass, it is mainly used in electronic devices and components seals outward, the sealing of bonding, the device of ceramics etc.

Background technology

In known technology, be widely used in that electronic devices and components, electron tube, semiconducter device are sealed, the electronic glass of sealing-in, all be to adopt PbO-B at present ₂O ₃-SiO ₂, PbO-ZnO-B ₂O ₃Material system, this material system sealing property is good, and electrical property is good, and moderate cost is the main flow of present seal glass.The subject matter that exists is the lead content height, and consumption is 50%～80%, in the production process of glass, operator's healthy and environment is caused great harm; The depleted element of sealing-in, PbO again can be molten in rainwater, soil, and environment is caused bigger harm.In order to reduce harm to human body, environment, developed barium crown sealed glass both at home and abroad again, main system has: Bi ₂O ₃-B ₂O ₃-SiO ₂, Bi ₂O3-B ₂O3-ZnO, V ₂O ₅-B ₂O ₃-ZnO, BaO-B ₂O ₃-ZnO etc., first three is planted, and the system prices of raw and semifnished materials are too high, and the per kilogram material cost is more than 100 yuan, and the 4th kind of material system coefficient of expansion is excessive, wants to reduce the coefficient of expansion, and material melting point will raise.The present invention is leaded at the above-mentioned materials system, cost is high puts forward.

Summary of the invention

The purpose of this invention is to provide a kind of preparation method of lead-free electronic glass, the lead-free electronic glass excellent electrical properties of its preparation, specific inductivity is little, dielectric loss, volume specific resistance height, disruptive strength height.

The technical solution adopted in the present invention is:

Preparation method of lead-free electronic glass, its special character is: the preparation raw material and the weight proportion thereof of lead-free electronic glass are:

B ₂O ₃30～80 parts; 10～30 parts of ZnO;

Na ₂CO ₃5～10 parts; CaCO ₃1～10 part;

1～5 part of feldspar;

Use the preparation method of above-mentioned materials:

(1), carry out accurate weighing, batch mixing is 30 minutes in mixer by above-mentioned materials;

(2), glass-melting furnace is installed crucible, be warmed up to 1300 ℃ of preset temperatures, reinforced;

(3), when glass melting evenly after, scoop out with the stainless steel spoon, slowly pour in the water quenching pool;

(4), water is put only taking-up material, 120 ℃～150 ℃ oven dry 2h in loft drier;

(5), the material that will dry packs in the ball mill, pack into the in advance ballstone of certainweight of ball mill; Ball milling is to certain hour, and 200 mesh sieves are crossed in discharging;

(6), weighing, the packing.

The preparation raw material and the weight proportion thereof of above-mentioned lead-free electronic glass material are:

B ₂O ₃60 parts; 17 parts of ZnO;

CaCO ₃10 parts; Na ₂CO ₃8 parts;

5 parts of feldspars.

The present invention is with respect to prior art, and its beneficial effect is as follows:

Adopting lead-free environment-friendly materials, can not produce harm, not produce harmful exhaust and waste water and waste residue human body aborning, be the environmentally friendly novel material of a kind of starting material environmental protection, production process environmental protection, product environmental protection; Lower cost for material, the per kilogram material cost is 10 yuan, contains tax, is easy to big area and promotes, uses; The glass excellent electrical properties, specific inductivity is little, dielectric loss, volume specific resistance height, disruptive strength height; Sealing temperature is low, can finish sealing-in at 600 ℃; The material coefficient of expansion mates with porcelain basal body at 7ppm.

Embodiment

The present invention is described in detail below in conjunction with the drawings and specific embodiments.

(1), the proportioning content of the moiety of material, each composition

The present invention by following material and weight proportion thereof is:

B ₂O ₃30～80 parts; 10～30 parts of ZnO; CaCO ₃1～10 part;

Na ₂CO ₃5～10 parts; 1～5 part of feldspar;

(2), the effect of each composition in prescription, content choose reason, the scientific theory that each composition is combined

The know-why of this project institute foundation is: in the glass that we can contact, can form glass network usually by three kinds of material: SiO ₂, B ₂O ₃, P ₂O ₅They are used alone or as a mixture, and become the base substance that forms glass, and the structure of glass has two kinds of theories at present: network theory and matted crystal theory.In glass, in order to adjust the character of glass, often add other oxide compound, these materials can be divided into two classes: a class is the body that scores a goal, as K ₂O, Na ₂O, CaO, MgO, BaO etc., their adding has destroyed the network structure of glass, makes the bonding fracture of glass, and high-temperature viscosity reduces; Another kind of is hermaphrodite, as PbO, and Al ₂O ₃, under certain conditions, be the body that scores a goal, under other situation, be glass-former.This project is selected B for use ₂O ₃As basic glass forming substances matter, be because of B ₂O ₃Low melting point character, B ₂O ₃Can be melt into liquid at 450 degree, and SiO ₂Fusing point 1680 the degree; Add K ₂O, Na ₂O reduces the high-temperature viscosity of glass as scoring a goal body, and in order to reduce the coefficient of expansion of glass, we add zinc oxide.Technological process is the same substantially with domestic glass, all to pass through batching, batch mixing, high-temperature fusion, form evenly, no bubble, do not have the not liquation of fusant, afterwards, for easy fragmentation, come out of the stove and promptly quench, chilling becomes fragment, and through super-dry, ball milling becomes can pass through 200 purpose powders, detect qualified after, the son industry of can powering is used.Make glass coloring if desired, can add colorant when batching, become molten addition, also can add colorant after glass is worn into fine powder, mixing is called mill addition method.The client can be sprinkling upon glass powder on the good workpiece of preheating in use, promptly forms light, fine and close, the coating that sticking power is good behind the sintering; Also glass powder can be added organic carrier, make electric slurry, with the workpiece roller coating, perhaps with glass powder furnishing suspension, with Work piece immersion, sintering gets final product afterwards.

Objectionable impuritiess such as the theory innovation of this project is to select for use the main material of the lower starting material boric acid of fusing point as prescription, and is not leaded add more zinc oxide, lower the high-temperature viscosity of material on the one hand, reduce the coefficient of expansion of material simultaneously.The coefficient of expansion of general glass and its fusing point---use temperature is inverse ratio, seek out low-melting glass material, the coefficient of expansion of material will be big, and zinc oxide is a kind of fusing point that both can reduce material unique in all oxides, can reduce the coefficient of expansion of material again.The linear expansivity of glass can be calculated with adding with formula is approximate:

α glass=α ₁P ₁+ α ₂P ₂+ α ₃P ₃+ ...

In the formula: the linear expansivity of α glass---glass;

P ₁, P ₂... each oxide weight percentage composition in the glass;

α ₁, α ₂... the linear expansivity of each oxide compound (trial value).

So the present invention has selected zinc oxide for use, we have added lime carbonate again in prescription, lime carbonate be fusing assistant be again opacifying agent, both can reduce the fusing point of material, can improve the covering power of material again.In material prescription, in order to reduce the high-temperature viscosity of glass, we have added a spot of potassium oxide and sodium oxide again, they are the intensive bodies that score a goal, can significantly reduce the fusing point and the melting viscosity of glass, but their intervention can cause the coefficient of expansion to become big, and can make the electrical properties in high temperatures variation of glass.For this reason, do following consideration when formulating of recipe: their add-on can not be big on the one hand, on the other hand, their usage ratio is determined with test, because there is mixed alkali effect in sodium potassium to the influence of electrical property, when a certain ratio, they stop migrating channels separately mutually, electrical property is significantly good, and we have found their ratio by test.The prescription of principle design according to this, the fusing point of glass is lower, at 600 ℃, i.e. fusing fully, and the coefficient of expansion is about 7ppm.Reach best fit with the coefficient of expansion of the porcelain basal body of wire wound resistor.The basically identical of operational path and electronic glass all will pass through batching, batch mixing, melting, quenching, ball milling, sieve, adds operations such as colorant, check, packing.

(3): followingly provide a kind of material preparation method

1, carry out accurate weighing by above-mentioned materials, be accurate to 1g, batch mixing is 30 minutes in mixer;

2, glass-melting furnace is installed crucible, be warmed up to 1300 ℃ of preset temperatures, reinforced;

3, after glass melting is even, scoop out, slowly pour in the water quenching pool with the stainless steel spoon;

4, Jiang Shui is put only, takes out material, 120 ℃～150 ℃ oven dry 2h in loft drier;

5, the material that will dry is packed in the ball mill, pack into the in advance ballstone of certainweight of ball mill; Ball milling is to certain hour, and 200 mesh sieves are crossed in discharging;

6, weighing, packing.

(4): the material property according to preparation method's preparation of the present invention is as follows:

Color: green;

Softening temperature: Tg=480 ± 5 ℃, Tf=510 ± 5 ℃;

Sealing temperature: 560 ℃～620 ℃;

Water tolerance: 0.2104mg/cm ²

Volume density: 2.9668g/cm ³

Specific inductivity: (5.85～7.65);

Dielectric loss: (86～109) * 10 ^-4

Volume specific resistance: room temperature (1.95～3.95) * 10 ⁸M Ω cm,

300℃(1.01～3.69)×10 ⁶MΩ·cm；

Disruptive strength: 〉=23.08kv/mm;

Folding strength: (117.65～146.57) MPa;

Thermal expansivity, 70.5 * 10 ^-7℃ ^-1

Embodiment 1:

1, prescription

B ₂O ₃60 parts; 17 parts of ZnO; CaCO ₃10 parts;

Na ₂CO ₃8 parts; 5 parts of feldspars;

Carry out accurate weighing by the above-mentioned materials proportioning, gross weight is 1Kg;

2, batch mixing is at V-type mixer batch mixing 20min;

3, crucible is put in melting well in crucible oven, and programmed is warmed up to 1300 ℃, and is reinforced, connects material for the second time behind the 20min, till filling it up with crucible, takes out behind the melting 20min again, slowly pours in the container that water is housed;

4, after oven dry will expect that melting finishes, outwell water, drain away the water, material is packed in the clean enamel tray, dry 2h at 120 ℃～150 ℃;

5, in the material that will dry of ball milling was packed ball mill into, the weight of ballstone was 2 times of material, ball milling 3h;

6, whole mistake 200 mesh sieves of the material that ball milling is good that sieve, minus mesh is finished product.

Embodiment 2:

1, prescription

B ₂O ₃70 parts; 10 parts of ZnO; CaCO ₃5 parts;

Na ₂CO ₃10 parts; 5 parts of feldspars;

Carry out accurate weighing by the above-mentioned materials proportioning, gross weight is 1Kg;

2, batch mixing is at V-type mixer batch mixing 20min;

3, crucible is put in melting well in crucible oven, and programmed is warmed up to 1300 ℃, and is reinforced, connects material for the second time behind the 20min, till filling it up with crucible, takes out behind the melting 20min again, slowly pours in the container that water is housed;

4, after oven dry will expect that melting finishes, outwell water, drain away the water, material is packed in the clean enamel tray, dry 2h at 120 ℃～150 ℃;

5, in the material that will dry of ball milling was packed ball mill into, the weight of ballstone was 2 times of material, ball milling 3h;

6, whole mistake 200 mesh sieves of the material that ball milling is good that sieve, minus mesh is finished product.

Embodiment 3:

1, prescription

B ₂O ₃80 parts; 10 parts of ZnO; CaCO ₃3 parts;

Na ₂CO ₃5 parts; 2 parts of feldspars;

Carry out accurate weighing by the above-mentioned materials proportioning, gross weight is 1Kg;

2, batch mixing is at V-type mixer batch mixing 20min;

3, crucible is put in melting well in crucible oven, and programmed is warmed up to 1300 ℃, and is reinforced, connects material for the second time behind the 20min, till filling it up with crucible, takes out behind the melting 20min again, slowly pours in the container that water is housed;

4, after oven dry will expect that melting finishes, outwell water, drain away the water, material is packed in the clean enamel tray, dry 2h at 120 ℃～150 ℃;

5, in the material that will dry of ball milling was packed ball mill into, the weight of ballstone was 2 times of material, ball milling 3h;

6, whole mistake 200 mesh sieves of the material that ball milling is good that sieve, minus mesh is finished product.

Claims (2)

1. preparation method of lead-free electronic glass: it is characterized in that: the preparation raw material and the weight proportion thereof of lead-free electronic glass are:

B ₂O ₃30～80 parts; 10～30 parts of ZnO;

Na ₂CO ₃5～10 parts; CaCO ₃1～10 part;

1～5 part of feldspar;

Use the preparation method of above-mentioned materials:

(1), carry out accurate weighing, batch mixing is 30 minutes in mixer by above-mentioned materials;

(2), glass-melting furnace is installed crucible, be warmed up to 1300 ℃ of preset temperatures, reinforced;

(3), when glass melting evenly after, scoop out with the stainless steel spoon, slowly pour in the water quenching pool;

(4), water is put only taking-up material, 120 ℃～150 ℃ oven dry 2h in loft drier;

(5), the material that will dry packs in the ball mill, pack into the in advance ballstone of certainweight of ball mill; Ball milling is to certain hour, and 200 mesh sieves are crossed in discharging;

(6), weighing, the packing.

2. lead-free electronic glass preparation methods according to claim 1: it is characterized in that: the preparation raw material and the weight proportion thereof of described lead-free electronic glass are:

B ₂O ₃60 parts; 17 parts of ZnO;

CaCO ₃10 parts; Na ₂CO ₃8 parts;

5 parts of feldspars.