KR102379829B1 - Lead-free low temperature calcined glass frit, paste and vacuum glass assembly using the same - Google Patents

Abstract

The present invention relates to a lead-free low-temperature fired glass frit, paste, and a vacuum glass assembly using the same.
The glass frit according to the present invention has a new component system including P ₂ O ₅ , V ₂ O ₅ , TeO ₂ , CuO, ZnO and BaO in a composition ratio unique to the present invention, thereby replacing the conventional flexible glass composition and allowing low-temperature firing It is possible, and it does not contain an inorganic filler or minimizes the content of the inorganic filler, and the thermal expansion coefficient with the glass substrate is matched, so that peeling or breakage does not occur and durability is excellent.

Description

LEAD-FREE LOW TEMPERATURE CALCINED GLASS FRIT, PASTE AND VACUUM GLASS ASSEMBLY USING THE SAME

The present invention relates to a lead-free low-temperature fired glass frit, paste, and a vacuum glass assembly using the same.

In glass windows, home appliances, or electrical and electronic components such as vacuum insulated multilayer glass panels, display panels, and organic EL display panels, sealing or adhesion is performed by a glass frit containing a glass composition and inorganic ceramic particles. Such a sealing glass frit is generally applied in the form of a paste, and the glass paste is applied to glass using a screen printing method or a dispenser method, dried and then fired to give a sealing function.

Conventionally, a PbOB ₂ O ₃ based glass composition containing a very large amount of lead oxide has been widely applied. The PbOB ₂ O ₃ glass composition had a softening point of approximately 400 to 450° C., and exhibited good softening fluidity and relatively high chemical stability.

However, in recent years, the trend of design considering the environment has become stronger worldwide, and safer materials are demanded. For example, in Europe, a directive by the European Union (EU) on the restriction of the use of certain hazardous substances in electronic and electrical equipment (RoHS Directive) came into effect on July 1, 2006. In the RoHS directive, a total of six substances, including lead, have been designated as prohibited substances.

Since the PbOB ₂ O ₃ glass composition contains a lot of lead, which is designated as a prohibited substance in the RoHS directive, it is difficult to use it as a sealing glass paste. Accordingly, the development of a novel glass composition that does not contain lead has been required. In addition, in order to reduce thermal damage to various glass sealing parts or electrical and electronic parts and to improve productivity, the development of lead-free glass compositions capable of softening flow at a lower temperature than PbOB ₂ O ₃ glass compositions and having good chemical stability is strongly encouraged. It is being demanded.

According to the demand for a lead-free glass composition, a P ₂ O ₅ V ₂ O ₅ TeO ₂ lead-free glass composition is known as a lead-free glass composition that does not contain lead and can be fired at a low temperature.

However, the conventional P ₂ O ₅ V ₂ O ₅ TeO ₂ glass composition has a problem in that good softening fluidity cannot be obtained due to a high crystallization tendency during firing.

In addition, the conventional P ₂ O ₅ V ₂ O ₅ TeO ₂ based lead-free glass composition does not match the thermal expansion coefficient with the glass substrate even though it can be fired at a low temperature, so there is a problem that peeling or breakage may occur, and the thermal expansion coefficient is lowered. In order to lower it, there is a problem in that the product cost is increased by using a large amount of inorganic filler.

An object of the present invention is to provide a new lead-free low-temperature-fired glass frit capable of being fired at a low temperature as a lead-free glass composition replacing the conventional flexible glass composition.

In particular, an object of the present invention is to provide a novel lead-free low-temperature-fired glass frit that can be fired at a low temperature and has a low crystallization tendency even during low-temperature firing.

Another object of the present invention is to provide a lead-free low-temperature-fired glass frit excellent in durability without delamination or breakage by matching the coefficient of thermal expansion with a glass substrate.

In order to provide a new glass frit that can be fired at a low temperature as a lead-free glass composition that replaces the conventional flexible glass composition, the glass frit according to the present invention contains P ₂ O ₅ 5 to 25 wt%, V ₂ O ₅ 40 to 70 wt%, TeO ₂ 5-25 wt%, CuO 1-5 wt%, ZnO 1-12 wt% and BaO 1-5 wt%.

In addition, in order to provide a glass frit that can be fired at a low temperature and has a low crystallization tendency even during low temperature firing, the glass frit according to the present invention is the P ₂ O ₅ , V ₂ O ₅ , and the content of TeO ₂ may satisfy the following relational expression.

[Relational Expression]

V ₂ O ₅ (wt. %)/P ₂ O ₅ (wt. %) < 3.5

P ₂ O ₅ (wt. %) + TeO ₂ (wt. %) > 30

In addition, in order to provide a glass frit excellent in durability that does not contain inorganic fillers or minimizes the content of inorganic fillers, and the thermal expansion coefficient is matched with the glass substrate, so that peeling or breakage does not occur, the glass frit according to the present invention is Bi ₂ O ₃ , MnO ₂ , Fe ₂ O ₃ and Ag ₂ O may further include one or more.

The glass frit according to the present invention has a new component system including P ₂ O ₅ , V ₂ O ₅ , TeO ₂ , CuO, ZnO and BaO in a composition ratio unique to the present invention, thereby replacing the conventional flexible glass composition and allowing low-temperature firing There is a possible effect.

In addition, the glass frit according to the present invention is P ₂ O ₅ , V ₂ O ₅ , and TeO ₂ Since it can have an optimal ratio of the content, not only can it be calcined at a low temperature, but also there is an effect that the crystallization tendency is low even when calcined at a low temperature.

Furthermore, the glass frit according to the present invention is Bi ₂ O ₃ , MnO ₂ , Fe ₂ O ₃ And Ag ₂ O may further include at least one kind, and the coefficient of thermal expansion (CTE) after calcination may be in the range of 80 to 100 x 10 ^-7 /°C, so that it does not contain an inorganic filler or minimizes the content of the inorganic filler The coefficient of thermal expansion with the glass substrate is matched, so that peeling or breakage does not occur, and durability is excellent.

The above-described objects, features, and advantages will be described in detail below, and accordingly, those skilled in the art to which the present invention pertains will be able to easily implement the technical idea of the present invention. In describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the gist of the present invention, the detailed description will be omitted. Hereinafter, preferred embodiments according to the present invention will be described in detail.

The present invention is not limited to the embodiments disclosed below, but can be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete and to completely convey the scope of the invention to those of ordinary skill in the art. It is provided to inform you.

Hereinafter, a lead-free low-temperature fired glass frit, paste, and a vacuum glass assembly using the same according to the present invention will be described in detail.

<Lead-free low temperature firing glass frit>

Glass frit used as a sealing material generally has better fluidity at low temperatures when the temperature of physical properties such as glass transition point and softening point is low. liquidity may deteriorate.

In addition, when the sealing process is applied at a high temperature for glass used in home appliances or electronic products, there are problems such as glass breakage or process cost increase, so it is necessary to apply the sealing process at 400 ° C. or less. Therefore, the glass frit sealing material used in the sealing process should be capable of firing at a low temperature. In addition, it should be possible to sinter at a low temperature and at the same time satisfy appropriate softening fluidity.

Accordingly, the present inventors have completed a new glass frit that can be fired at a low temperature and has a low crystallization tendency.

Glass frit according to the present invention P ₂ O ₅ 5-25 wt%, V ₂ O ₅ 40-70 wt%, TeO ₂ 5-25 wt%, CuO 1-5 wt%, ZnO 1-12 wt% and BaO 1 to 5% by weight.

P ₂ O ₅ is contained in the range of 5 to 25% by weight in order to lower the firing temperature of the glass frit and control fluidity. If the P ₂ O ₅ content exceeds 25 wt%, it is easy to make the glass frit difficult to fire, and there is a problem in that fluidity is lowered. If P ₂ O ₅ is less than 5% by weight, the thermal expansion coefficient of the glass frit increases and there may be a problem in that the adhesion to the glass substrate is reduced.

V ₂ O ₅ has the effect of lowering the softening point while increasing the durability of the glass frit, and is contained in the glass frit in an amount of 40 to 70 wt%. When the V ₂ O ₅ content exceeds 70% by weight, there is a problem in that the sintering of the glass frit tends to be difficult. When V ₂ O ₅ is less than 40 wt%, it is difficult to sufficiently exhibit the effect of lowering the softening point of the glass frit, and also there may be a problem in the durability of the glass frit.

TeO ₂ has an effect of increasing the fluidity of the glass frit, and is contained in the glass frit in an amount of 5 to 25 wt%. If TeO ₂ exceeds 25% by weight, it may be difficult to sufficiently lower the softening point, so that firing may not occur. If TeO ₂ is less than 5 wt%, there may be a problem in that it is difficult to vitrify the glass frit depending on the balance relationship with other components.

CuO is contained in the range of 1 to 5 wt % to match the coefficient of thermal expansion of the glass frit and satisfy durability. When CuO exceeds 5 wt %, a problem in which the fluidity of the glass frit is lowered may occur. If CuO is less than 1 wt%, the required coefficient of thermal expansion of the glass frit may not be obtained.

ZnO is contained in the range of 1 to 12 wt% to match the coefficient of thermal expansion of the glass frit and satisfy durability. When the ZnO content exceeds 12 wt%, the fluidity of the glass frit is lowered, and adhesion to the glass substrate may be a problem. If ZnO is less than 1 wt%, the required coefficient of thermal expansion of the glass frit may not be obtained.

BaO is contained in the range of 1 to 5 wt % in order to match the coefficient of thermal expansion of the glass frit and satisfy durability. When CuO exceeds 5 wt %, a problem in which the fluidity of the glass frit is lowered may occur. If CuO is less than 1 wt%, the required coefficient of thermal expansion of the glass frit may not be obtained.

In addition, the glass frit according to the present invention is additionally Bi ₂ O ₃ , MnO ₂ , Fe ₂ O ₃ And Ag ₂ O may further include one or more, preferably the Bi ₂ O ₃ , MnO ₂ , Fe ₂ O ₃ In order to increase the durability of the glass frit and lower the crystallization tendency. and at least one of Ag ₂ O may be included in an amount of 25 wt% or less. Bi ₂ O ₃ , MnO ₂ , Fe ₂ O ₃ And when one or more of Ag ₂ O exceeds 25% by weight, the thermal expansion coefficient may be lowered, but a problem in that the sealing performance may be deteriorated may occur.

In addition, included in the glass frit according to the present invention, P ₂ O ₅ , The contents of V ₂ O ₅ and TeO ₂ are preferably contained so as to satisfy the following relational expression from the viewpoint of plasticity stability related to crystallization tendency.

[Relational Expression]

V ₂ O ₅ (wt. %)/P ₂ O ₅ (wt. %) < 3.5

P ₂ O ₅ (wt. %) + TeO ₂ (wt. %) > 30

As the content of _{V 2} O ₅ increases, the glass transition point of the glass frit decreases and the sealing temperature can be lowered, but at the same time, the crystallization tendency _of the glass frit increases _. Do. Accordingly, it is very desirable for the glass frit according to the present invention to have a composition ratio that satisfies all of the above relational expressions.

In addition, the glass frit according to the present invention preferably has a thermal expansion coefficient of 80 to 100 x 10 ^-7 /°C in terms of matching the thermal expansion coefficient with the glass substrate, and preferably has a softening point of 400°C or less. Since the thermal brim coefficient falls within the range of 80 ~ 100 x 10 ^-7 /℃, the glass frit according to the present invention can reduce the occurrence of lowering of the adhesive force, thereby improving the sealing reliability. In addition, since the softening point of the glass frit according to the present invention is 400° C. or less, the sealing process of the glass substrate may be performed at a low temperature of 400° C. or less.

In addition, since the glass frit according to the present invention has the aforementioned component system and composition ratio, it can have a low coefficient of thermal expansion even if it does not contain an inorganic filler or is included in a minimum content and has an advantageous effect of lowering the softening point.

If necessary, the glass frit according to the present invention may contain a small amount of inorganic filler. The inorganic filler is a crystalline inorganic particle having a low coefficient of thermal expansion, specifically zirconium phosphate, zirconium phosphate tungstate, zirconium, Li ₂ O-Al ₂ O ₃ -SiO ₂ , beta-eucryptite, and zirconium tungstate. more can be used.

<Glass Frit Paste>

Next, the glass frit paste according to the present invention includes 100 parts by weight of the aforementioned glass frit and 10 to 100 parts by weight of the organic vehicle.

When the amount of the organic vehicle is less than 20 parts by weight or more than 100 parts by weight, the application process may be difficult because the viscosity of the paste is too high or too low.

The organic vehicle may include an organic solvent and an organic binder. The organic solvent may use a solvent such as α-terpineol or butyl carbitol, and the organic binder may use ethyl cellulose, but is not limited thereto.

<Vacuum Glass Assembly>

A vacuum glass assembly refers to an assembly comprising two or more glass substrates and a vacuum is maintained between the two or more glass substrates. The vacuum glass assembly can also be used in home appliances such as refrigerators, microwaves, and washing machines, as well as electronic components of various electronic devices.

The glass frit according to the present invention may be used as a sealing material in the vacuum glass assembly.

When the glass frit paste according to the present invention is applied as a sealing material, the sealing process is possible at a low temperature of less than 400 °C. Therefore, when the glass frit paste according to the present invention is applied as a sealing material, the risk of damage to the glass substrate is lowered and the process cost can be reduced.

A vacuum glass assembly according to the present invention comprises: a first glass substrate; a second glass substrate spaced apart from the first glass substrate; and a sealing material arranged along an edge of the first or second glass substrate, bonding the first and second glass substrates, and sealing a space between the first and second glasses, wherein the sealing material includes a sixth The paste according to claim is applied and fired to form.

The first glass substrate and the second glass substrate of the present invention may be selected according to the requirements of the article to which the vacuum glass assembly is applied, and is not particularly limited.

In addition, the above-mentioned glass frit paste is used as the sealing material.

Hereinafter, specific aspects of the present invention will be described by way of Examples.

<Example>

<Manufacture of glass frit>

Glass frits having the composition ratios shown in Table 1 were prepared. The raw materials of each component were thoroughly mixed for 3 hours in a V-mixer. Here, the raw material of BaO is BaCO ₃ , the raw material of P ₂ O ₅ NH ₄ H ₂ PO ₄ was used, and the remaining components were the same as those described in Table 1 were used. The mixed materials were sufficiently melted for 1 hour at 800-1000° C., and then rapidly cooled with a quenching roller to obtain a glass cullet.

After controlling the initial particle size of the glass cullet obtained in the above process with a ball mill, it was pulverized for about 1 hour using a jet mill and passed through a 325 mesh sieve (ASTM C285-88) to control the particle size so that the glass powder that did not pass remains within 1 g. .

[Table 1]

<Paste Manufacturing>

After preparing an organic vehicle by mixing α-terpineol and ethyl cellulose in an appropriate ratio, a paste was prepared by mixing it with the glass frit prepared as above in an appropriate ratio. A three roll mill was used for uniform mixing.

<Preparation of vacuum glass assembly specimen>

Two glass substrates were prepared, and the pastes according to Examples 1 and 2 and Comparative Examples 1 and 2 were applied to the outer portion of each glass substrate to prepare a total of four glass assembly specimens. For these glass assemblies, evacuation and sealing processes were performed at 400°C. Accordingly, a total of four glass assembly specimens were completed.

<Experimental example>

The glass frits, pastes and specimens prepared in Examples and Comparative Examples were measured as follows, and the results are shown in Table 2.

1. Glass transition temperature (Tg)

The glass transition point was measured at a temperature increase rate of 10 °C/min using a TMA instrument (TMA-Q400 TA instrument).

2. Coefficient of thermal expansion (CTE(x10 ^-7 /℃))

The coefficient of thermal expansion was measured using a TMA instrument (TMA-Q400 TA instrument) at a temperature increase rate of 10 °C/min.

3. Haf Ball Temperature

Using a high-temperature microscope, when the glass frit exists in powder form at a temperature increase rate of 10 °C/min, it was observed when the glass frit shrinks the most and takes on the shape of a half ball at each temperature.

4. Water resistance

After the specimen was immersed in a distilled water thermostat at 90° C. and maintained for 48 hours, the color change and weight change of the distilled water were observed. The weight after immersion was measured, and the case where the weight increase/decrease rate was less than 1% was denoted by ○, and the case where the weight was greater than 1% was denoted by Х.

5. Plastic Stability

The glass frit powder was filled and press-molded in a metal mold, and the temperature was raised to 600°C at 10°C/min to observe crystallization after firing. ◎: Crystallization does not occur and gloss is very good, ○: Crystallization does not occur and gloss is good. Х: Crystallization occurs and there is no gloss.

[Table 2]

As described in Table 2, the embodiment according to the present invention has a half ball temperature of 400 ° C. or less, so that not only can it be fired at a low temperature, but also the thermal expansion coefficient corresponds to 90 to 100, which is matched with the glass substrate, and also has water resistance, It can be confirmed that the plastic stability is excellent.

The comparative examples relate to a glass frit having a P ₂ O ₅ V ₂ O ₅ TeO ₂ component system, and it was confirmed that the softening point was higher as compared to the Example, and the sealing was not performed properly, so that the water resistance and plastic stability were unsatisfactory.

Although the present invention has been described as described above, the present invention is not limited by the embodiments disclosed herein, and it is apparent that various modifications may be made by those skilled in the art within the scope of the technical idea of the present invention. In addition, even if the effect of the configuration of the present invention is not explicitly described and described while describing the embodiment of the present invention, it is natural that the effect predictable by the configuration should also be recognized.

Claims (9)

P ₂ O ₅ 5-25% by weight,
V ₂ O ₅ 40-70% by weight,
TeO ₂ 5-25% by weight,
1-5 wt% CuO;
1-12 wt% ZnO and
1 to 5% by weight of BaO,
Does not contain inorganic fillers,
After firing, the coefficient of thermal expansion (CTE) is within the range of 80 ~ 100 x 10 ^-7 /℃
glass frit.
The method of claim 1,
The P ₂ O ₅ , V ₂ O ₅ , and the content of TeO ₂ Glass frit, characterized in that it satisfies the following relational expression.

[Relational Expression]
V ₂ O ₅ (wt. %)/P ₂ O ₅ (wt. %) < 3.5
P ₂ O ₅ (wt. %) + TeO ₂ (wt. %) > 30
The method of claim 1,
Bi ₂ O ₃ , MnO ₂ and Fe ₂ O ₃ Glass frit, characterized in that it further comprises at least one.
According to claim 1,
Glass frit, characterized in that the softening point is 400 ℃ or less.
A composition comprising 100 parts by weight of the glass frit according to any one of claims 1 to 4 and 10 to 100 parts by weight of an organic vehicle.
Glass frit paste.
a first glass substrate;
a second glass substrate spaced apart from the first glass substrate; and
a sealing material arranged along an edge of the first or second glass substrate, bonding the first and second glass substrates, and sealing the space between the first and second glass;
The sealing material is formed by applying the paste according to claim 5 and firing
vacuum glass assembly.
According to claim 1,
Bi ₂ O ₃ Glass frit, characterized in that it further comprises.
P ₂ O ₅ 5-25% by weight,
V ₂ O ₅ 40-70% by weight,
TeO ₂ 5-25% by weight,
1-5 wt% CuO;
1-12 wt% ZnO and
1 to 5% by weight of BaO,
I do not include an inorganic filler,
glass frit.
P ₂ O ₅ 5-25% by weight,
V ₂ O ₅ 40-70% by weight,
TeO ₂ 5-25% by weight,
1-5 wt% CuO;
1-12 wt% ZnO and
1 to 5% by weight of BaO,
Ag ₂ O further comprising,
glass frit.