JPS5964544A - Sealing glass frit - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION PBO-containing sealing glasses! 1゛, - pbO-
B2O3-ZnO sealing glass is most commonly used commercially to seal glass faceplates to the glass funnels of color television tubes.

These sealing glasses are typically manufactured at low temperatures, which promotes moist conditions on the glass surfaces being sealed.
It has a melting point and a pour point of less than 173'c, preferably less than 173'c. Additionally, the formed opacified or crystallized seal also has a higher fiber softening point than that of the original sealing glass. However, if the sealing process is carried out in a reducing atmosphere or in harmful gases outside the machine, PbO in the sealing glass is easily reduced to metallic lead. Television tube manufacturers must take special steps to prevent dielectric breakdown of seals due to stiffness.

Before the glass faceplate of a color television tube is sealed to its glass funnel, both parts must first be subjected to a number of different processing steps. The face plate 1 and the metal grid and perforated mask, which form an important part of the inner surface of the face plate, are first bonded and then introduced into the fixing process.
Here this joint is partially heated at a heating rate of about tS at 10°C.
Heated to a flow rate of 0°C, about 2
Time is maintained.

This fixation process standardizes the various changes that occur between the two parts during the subsequent heating and cooling stages during the formation of the finished television vacuum tube.

After the kneaded parts have cooled, the grid or perforated mask is removed and marked for subsequent bonding with a similar glass face plate.

This faceplate is then colored with green color by a known method.
A sharp contrast is provided by the blue and red phosphors being applied separately and optionally a carbon map 7: a graphite background being applied around the phosphors. Each phosphor is a regularly arranged collection of individual dots present on the inner surface of the faceplate. A resin or plastic film is applied to the surface of the phosphor, and the inner surface of the face plate is aluminized, that is, a thin aluminum film is applied under vacuum.
1, conductivity is formed. This aluminum adhesion surface is the metal stud (5tu) on the inner surface of the faceplate.
d), while this stud connects to the sealing surface of the faceplate and the funnel. It is connected by a spring clip connecting the i-conducting inner surface. On the other hand, the inner surface of the funnel is connected to the cathode terminal on the outer surface of the funnel.
1. Connect to the television center's high voltage supply with a power comb. Once this aluminum deposition step is complete, a grid or perforated mask is inserted into this faceplate and secured there. do. At this stage, at least about nine organic compounds are applied to the inner surface of the faceplate, and these compounds are subsequently baked into the faceplate or faceplate. ,
No. This 'baking', which is normally carried out at temperatures between l10° and tSO°, generates various organic gases during the process. Since the organic gases from the mold can have a harmful effect on the PBO contained in the sealing glass used to seal the faceplate to the funnel, such a sealing process is required during the baking process. Do it before λ
If such debris comes into contact with the sealing glass during the sealing process, PB
o is reduced to a metallic vessel, causing dielectric breakdown of the resulting seal. Such a vacuum tube is unusable, and the voltage 1:l:
Items that do not pass the test are returned. To recover the faceplate and funnel for reuse from returned tubes, the sealing glass must be partially corroded and the tubes then undergo thermal cycling.
The faceplate and funnel must be removed, the glass solder removed from the parts, any phosphor or other material deposited from the faceplate, and the faceplate must be used again. This process is time consuming for television manufacturers.
It is a samurai, and it is also a cost loss. The high voltage applied to the television vacuum tube while it is working on a television set is from 20 Kpol I to more than 33 r < Pol I - and the seal between the Noah panel and the face plate 1. Induced destruction occurs due to incomplete operation of vacuum tubes (MALF).
This can result in electric shock when a person hits the vacuum tube.

As mentioned above, the metal grid or perforated mask
Between the time it is joined to the Ace plate and the time this plate is subsequently sealed to Noanel with sealing or glass solder, the faceplate is subjected to approximately g~/2 separate processing operations, such as inspection, After firing and various treatments,
For example, the edges of the faceplate that is sealed to the funnel must be etched and various components must be removed after re-inspection. Eliminating some or all of the steps between inserting the mask into the faceplate and sealing the faceplate to the Noanel saves labor and time, resulting in a complete color television. This also reduces the manufacturing cost of vacuum tubes.

However, because out-of-plane scum is often formed during the firing process that the faceplate must undergo, the television vacuum tube manufacturing industry uses Pb for firing the faceplate and sealing the faceplate to the noanel.
Simultaneously using an O-containing sealing glass was not possible without undergoing reduction of PbO in the sealing glass to pb-Kinzo.

Furthermore, pbo-B2O3-ZnO glass (D) is the only binder that has been commercially successful in its use for PbO-containing sealing glasses, with amyl acetate as the preferred solvent for it. It is only a solution containing nitrocellulose/~/, t%.

When other binders are used in place of nitrocellulose, the pbo is not completely prevented from reducing the pb gold metal during the sealing process. In this case, instead of the yellow seal formed by the opaque glass solder, the presence of metallic lead results in the formation of a gray or grey-black seal. However, nitrocellulose also overcomes many drawbacks when used as a binder in sealing glasses.

First of all, pastes containing such burners are unstable and have a lifespan of only about a few hours.

This means that the color television tube manufacturer must mix the paste immediately before applying it from the distributor to the outer sealing edge of the entire funnel. It is not possible to dispense more than approximately 201b (9, Ogkti) in 7 doses and feed it into the distributor. Additionally, extreme care must be taken in dispensing the ribbon or bead of sealing glass paste from the distributor orifice to the outer periphery of the noanel edge. The operator of the dispensing device must constantly adjust the pressure while the paste is being extruded to maintain substantially uniform width and weight of the ribbon. The width of this ribbon must be narrower than the width of the Noanel edge, so if this width is too wide, a large amount of paste will come out from between the joint surface of the Noanel and faceplate during the sealing process. . On the other hand, if this width becomes too narrow, the unapplied paste will not be able to form an effective and acceptable seal.

When actually using a PbO-containing glass solder paste with nitrocellulose as a binder, the width of the extruded ribbon and the weight of the extruded ribbon to a certain length can be changed to quickly convert it to another Noel. It is also true that there are many cases where extrusion molding is necessary. This means that the person operating the distributor must constantly monitor and adjust the distribution kS.

Approximately 700 television vacuum tubes measuring 23" (3gcj+1) diagonally with 20+b (9, Ogkti) sealing crows were made in about 2 hours.
(Otsu cm) In the case of vacuum tubes, you can make 75 pieces in about 3 hours. After this, the distributor used was stopped, the sealing glass paste tank was taken out, about 720 to 300 g of residual paste was removed from the tank, and it was discarded.
Clean this tank and mix it with a new one f;, 20
+b (9, OgJcti) Nohes h formulation 46
Please fill up the tank.'' -No. This tank is again loaded into the distributor, the air port is connected to reduce the loss of amyl acetate that evaporates at room temperature, the air [U:, wo is adjusted, and this is again poured into the outer edge of the television noannel. Start extruding the paste. Niton, a manufacturer of color television vacuum tubes, uses nitrocellulose as a binder for sealing glass flint, which is still used today because it is impossible to distribute it. ,01b(9,0
As for 8' and 9), the driver rotates the machine in reverse while constantly monitoring it, and also periodically stops the machine, mixes and prepares a new sealing glass composition, and restarts the machine.
And operations such as adjustment are expensive. Kowara manufacturers believe that nitrocellulose can reduce P in the glass due to the reducing atmosphere created when other binders are used.
Efforts have continued to be made to overcome the limitations and drawbacks of nitrocellulose, since it is intended to avoid dielectric breakdown of sealing glass caused by reduction of bo. Kowara manufacturers have also demonstrated that by separately firing the phosphor-containing faceplate before sealing the glass faceplate to the glass noanel, out-of-plane evaporation formed during the firing step no longer causes sealing. Efforts have also been made to prevent the reduction of I)bO in glass to pb gold π, which causes dielectric breakdown and causes the return of vacuum tubes.

PbO-containing "lambda" is present in the color paste for sealing obtained from "glass frit for glass molding" 1] White bodies are normally in the form of lower oxides of metals such as PbO-BaO, etc. The high oxide form present in the sealing glass does not decompose even with the heat, softening, and humidity during which the sealing glass is heated to seal the faceplate to the noanel. If the powder of a metal higher oxide is present in sufficient slipperiness, the sealing glass will melt, and even if the sealing glass comes into contact with a reducing agent during sealing, the higher oxidation of the metal will be prevented. It has been found that the PbO in the sealing glass cannot be reduced to PB gold π only when the material is reduced to its lower oxide state. Furthermore, the PbO-containing sealing glass is coated with at least 0.0% of the sealing glass in powder form.
When adding b304, the amount of PbO in the sealing glass decreases by about 11), preferably from about 0.2S to 0.7% by weight. It has also been found that returning to the North may be avoided. This Pb3C
) + is reduced to PbO and formed λ] 111
PbO does not adversely affect the properties of the sealing glass.

The use of Pb5O4 powder in pbo-containing sealing glass is a result of the sealing glass coming into contact with vapors liberated from various organic components used in the interior of television vacuum tubes or television vacuum tube parts. It would be possible for color television tube manufacturers to avoid aging of the sealing glass that occurs as a result.

Furthermore, when adding such a small amount of PB3O4 powder to a paste prepared from sealing glass and raw material, it is possible to kill the paste by using a small amount of hydroxypropyl cellulose binder together with a nitrocellulose binder, as is clear from the reference examples described later. It has also been revealed that 7.2% nitrocellulose solution and 30% hydroxypropylcellulose solution are present by weight/
An extremely stable sealing glass paste is obtained which can be prepared by mixing the same amount (several thousand bottles) (0,5-X thousands to nine), and which will last for at least three months or so. ] Cures the shelf life of ten. Additionally, the paste can be used continuously in a dispensing device from start to finish without requiring constant adjustment of the dispensing device as is required when using nitrocellulose alone as a binder for glass frits. This results in reduced labor for the manufacturer, reduced dispenser operation time, reduced paste preparation time, etc.

Reference example / In 750 parts by weight of amyl acetate that has been preheated to 0°C, while stirring, the average molecular weight
2 t parts by weight of hydroxypropyl cellulose or λ was also slowly injected. Add 750 parts by weight of acid-resistant amyl to this solution and stir well. Slowly add 300 parts by weight of ethylene glycol methyl ether preheated to 0°C to this solution, while stirring continuously. A 7% by weight clear solution of hydroxypropyl cellulose was formed. Q: 3 parts by weight of the 7% by weight solution of hydroxypropyl cellulose prepared in this way was mixed with a solution of nitrocellulose dissolved in acid-resistant amyl (in a solvent). The nitrocellulose content of /-,2flt1i%) is well mixed with heavy electric j'%. The obtained binder solution was mixed well with a commercially available glass solder //70 Ichiyakubu containing P b s O 4 in an amount of 23% by weight. The glass solder had the following composition: pb
o 73.3%, B203g, 3%, ZnO/,! %.

5j02.2%, BaO2%.

The glass solder paste thus prepared was stable for 50 hours in the formulation at room temperature. When distributed in beads on a TV sofa panel and baked at a humidity of approximately +730° C., this glass solder softened and then became fluid and translucent. The color of the seal was orangey yellow, indicating that some Pb3O4 remained in the seal and was not completely reduced to PhO.

Even after extruding and pasting the ribbon-like ribbons for several hours, no significant changes were observed in the width of the 7J-in.

Hydroxypropylcellulose comprising 0.795% by weight vehicle was used in this example.

Reference example! Nitrocellulose in amyl acetate solution 9X (IJ) m
To prepare a glass solder paste, 100 parts by weight of trocellulose/2tjL (% by weight) was mixed with 7770 parts by weight of the glass solder used in Reference Example/.

This paste is stable for only about an hour, and when this paste is dispensed into the noanel section of the vacuum tube, continuous pressure is applied to the dispenser to keep the bead sizes within a substantially uniform range. had to be added.

Furthermore, the beads that had not been extruded got stuck on the outside of the car.
About 30% of the MC amount of F9r honey ribbon or λ1
These changes required continuous adjustments in the distributor to keep the ribbon weight constant.

Reference Example 3 A paste was prepared in the same manner as in Reference Example 2 except that glass Kenta/, 230 kg 1η1 was used. This mixture did not enter the extrusion starting section in the distributor, but A pressure of 3-.2 psi (0-371 Cglcrj) was applied to the ribbon, and the ribbon thus extruded was 0.2/3"
Bead width of (0, evening!/Cm) and IO per unit length,
It had a weight of 1g. Same-LI: After 7 hours by force.
, the width of this extruded bead is 0227"C0,37
7 cm), the weight per unit length was 10/-33, and the increase rate was 24%. After applying similar pressure to this formulation for 2 hours, the bead width was 0.239”
([, Otsu07Cm), while the weight per unit length is //7. 0g, which was a % increase rate. After 3 hours, the bead width will be 0.2 and 2" (0, Otsull)
OCm), the weight per unit length was /23 g, an increase rate of 311%. 30 of weight per crown length
% is the allowable limit, and if it exceeds the bend, it will not be pushed out between the sealing surfaces of the vacuum tube and will be wasted.
Or, in the worst case, it may cause the formation of undesirable stress points that may interfere with the handling and operation of the cathode ray tube. Therefore, the vacuum machine failed to extrude;
Set the width of approximately 0, . 2/3"(0,!; 11./Cm) Care must be taken to reduce the extrusion pressure by 1 at regular intervals during the resting period.

Reference example Reference example/100 parts by weight of glass solder used/
After mixing with Pb3O4 powder of 3% by weight, the obtained glass powder has an average molecular weight of about 3% by weight.

9 hydroxypropyl cellulose! % by weight of ethylene glycol methyl ether and amyl acetate dissolved in an isostatic compound. The resulting glass solder paste was stable and distributed well from a distributor similar to that used in Reference Example 3 without adjustment of the extrusion pressure. The diameter of the distributed beads or ribbons is approximately 1000g (<0.02cm).

Fire 11L made J] Crow bolt for sealing 10.00
/ inch (volt 10, oorsqcm) or V/m
The strength of the temptation to become a celebrity in il (dielectri)
c strength ) was 133% of that of conventional sealing glass flint.

Nitrocellulose binder 'I' When used for German sealing glass, firing spring/ko sealing glass 17
) The dielectric strength is /00~/! ; OV/mi I (
It is known that the dielectric strength is lower than the dielectric strength of the ordinary sealing glass frit itself.

Hydroxypropylcellulose comprising vehicle S weight percent was used in this example.

Reference example! A 7.33% solution of hydroxypropyl cellulose (average molecular weight approximately 300,000) in isobaric 1 tso ethylene glycol methyl nitrate amyl acetate was prepared with /wt% Pb3O4 with a sealing glass solder similar to the reference example. Mixed with those containing tusk]. Karasu Hanta + PbaO
+Comparison of solid to binder solution was //3:/. The resulting paste had not only good dispersibility but also good uniform bead manufacturing properties. The dielectric strength of the seal made with this glass dinter paste is 2S% higher than that of glass powder alone, gO% higher than that of the standard binder solution of glass powder and reference example, and P
The strength was 750% higher than that of a glass solder paste prepared in the same manner as Reference Example j except that it did not contain b304.

Hydroxypropylcellulose comprising 7.33% by weight vehicle was used in this example.

Reference example 4% solution of hydroxypropyl cellulose in amyl acetate and ethylene glycol methyl ether in
% and 90% nitrocellulose in amyl acetate (/, 2% nitrocellulose solution) / parts by weight, and // 7 parts by weight of solid material (reference example / glass solder + 0.3% by weight) A glass hammer paste was also prepared using pbso4) and J.

This paste remained stable after 6 days. After that, when distributing it into ribbons, the width of the beads is -o,
oog “See if there is a change in <o, oron)” 1. The change in heavy electric current per unit length was only +3%.

Vehicle 0, hydroxypropylcellulose comprising 8% 'lm is used in this example, 11.

Reference Example 7 The overlapping part of the glass hammer in Reference Example 1 containing 0.3% by weight of Pb3O4, or the same 70% by weight nitrocellulose solution as in Reference Example B, was also used as a reference example. Hydroxypropyl cellulose m solution 30, rit it%, same as B
Binder solution/fI'i: 171 parts was mixed.

Even after 21 hours, this base) was stable and suitable for extrusion into ribbons.

Hydroxypropyl cellulose comprising vehicle i, x mm% was used in this example.

Reference Example g Similar to Reference Example/, 7770 parts by weight of sealing glass containing 0.23% Pb3C)a was mixed with 90% of the nitrocellulose binder solution of Reference Example B, and kneaded in the same manner as Reference Example B. A sealing paste was prepared by mixing with 100 parts by weight of a 70% hydroxypropyl cellulose binder solution.This paste was placed in a distributor similar to the one used in Reference Example 3. λ1 was jealous.

2-. 2 ps'+ (0/!; 3 to 9/crl) (
D Pressure Te') Hon'j k Ke beads are extruded] The beads thus obtained are o,,2ss"< o Otsu1
1 fcm), and the weight per unit length is 78. It was Geg. When operated at the same extrusion pressure, the bead width was 0.1 mm after 7 hours. ? The bead width was 0.7" (0.7 g cm), and the weight per unit length was also 3%, showing a 3% increase rate. After 2 hours, the bead width was 0 with the same extrusion pressure.
．． 213"< 0.7/9Cm) The weight per unit length is g3.l1g, indicating the % increase rate. After 3 hours, the bead width is 0.2g3" (0.7/9Cnl), The weight was gg, jg, and showed an increase rate of g% per unit length σ. After 1 hour, the bead width is 0.2g'7"C0
,7,29Cm) and jRfj; is 8. ffg, the increase rate per unit length was 9% (5 The extrusion pressure was 21.2 psi (0-/5
9/ca). From these λ1, etc.,
The variations in bead width and weight per unit length were within the tolerances required in the television tube manufacturing industry.

For this reason, when using the sealing glass paste, compared to the case of using the conventional glass solder/zeta paste as shown in Reference Example 3, which requires constant monitoring, it is possible to This has the advantage that the distributor can be left unmonitored for long periods of time with only occasional spot checks.

In general, the dispensing device for making beads or ribbons of glass solder paste includes a central glass solder paste supply (c) such that the device is continuously charged with glass solder.
internal 5older glass paste
5upply) can also be adopted. Such a dispensing device distributes the glass solder paste at 2 o + b
(9.08' kg) at a time, which is used by most color television tube manufacturers today, requiring frequent equipment downtime. 20+b
(q, 08kq) Unlike the hatch method, continuous operation all day is possible. By the time I knead it, I've run out of it'°
The term "is" per unit refers to the length of the ribbon that will completely mold the outer sealing edge of the noanel section of a television vacuum tube without having to cut or rasp it.

Reference Example 9 Glass solder frit for sealing containing 0.3% PbaO+/230 parts by weight of nitrocellulose-dissolved NZ (
Nitrocellulose in amyl acetate/, 2%) 9! %and,
A sealing glass paste was prepared by mixing with a binder solution comprising 5% of a solution containing 1% of hydroxypropylcellulose in equal parts ethylene glycol methyl ether and amyl acetate. This sealing glass had the following composition: pbo7t%, ZnO/2-
Otsu%, BaO3g'-3%l51022.7%, and Ba02% (all weight%). 7g of this paste
(Il otcm) 0 mask, phosphor coating, aluminum treatment coating, etc. extruded into the noanel part of the television vacuum tube (/8" (Il otcm) is measured from the diagonal line of the vacuum tube surface) The faceplates to be discussed are joined at each nonel so that their sealing edges are joined with glass solder ribbons.The joined television parts are then placed in an airless oven. About 10°C per 7 minutes, 1Iso°C Noah 7, at iy degree.
It was heated outside for 1 hour and kept in this temperature for 7 hours. Is this true? ! -: The tube was cooled to room temperature at a rate of 7°C per 7 minutes. Not only the face plate λ1 sealed to the vacuum tube Noanel, but also each seal between this face plate 1 and Noanel, the Towara face plate and Noanel's interior refinement (1nter).
It may also be contacted with vapors liberated from volatile organic components in the confinement.

Each tube was tested for frit breakage.
own test). A gold Ji51 +) ring is placed so as to contact the seal near the outer periphery of the connection between the face plate and Noanel, and is the cathode terminal of Noanel! rOKV voltage could not be applied. No immediate dielectric breakdown was observed, nor were there any signs of failure. All of the vacuum tubes that were manufactured did not suffer from any dielectric damage, nor did any current flow through their seals.

However, in the case of television vacuum tubes that have been sealed with conventional glass solder and have been sealed and treated as shown in this reference example, P in the glass solder is
Dielectric breakdown was observed due to the pb gold metal reduction [λ] such that the bO conducts electricity through the seal.

Hydroxypropyl cellulose comprising 0.1.21% vehicle was used in this example.

PbO-containing glasses are commercially available for sealing the faceplate of a TV tube to a noanel section. Many of them are pbo'' B2O3-ZnOjJ and are in the following general composition ratio range: Ingredient Weight %pbo
7! -4;2 ZnO7~/1 B203 Otsu, S~/2Si
02/-3~3 Other metal oxides are also compatible with glass and do not change the material of the opaque seal formed from glass or its glass. (usually less than 5%) can be present if present.

---On the other hand, the solution of lulose in the lQt m amyl is well known as the Callas Seal River binder solution, and the amount of nitrocellulose in this solution is usually about /~/, 4%.

Nitrocellulose binder has P b 304 t T
It can be used with glass flint for Lucille. However, unless about 5% to 30% of a 1% solution of hydroxypropyl cellulose in a solvent is present as a binder solution, together with the nitrocellulose, the map ζ is preferably present as the sole binder solution in the sealing glass. Paste shelf life (5helf)
1ife) will be shorter. Although a 1% hydroxypropyl cellulose solution is described as a preferred Nahinder solution, other concentrations of this binder solution may be used.

The molecular weight of hydroxypropylcellulose is approximately po, oo
You can change the amount between 0 and 300,000, or even more than that. The larger the molecular weight, the more difficult it is to use. Other binders also have the ability to maintain the glass solder frit in a ribbon shape long enough to bond and seal the parts to be joined, i.e. face solder and noanel. As long as it can be used as color paste for stickers. The binder required for the paste must be one that can extrude the crow solder frit in a wet state and maintain that state for a certain period of time, such as beads or ribbons. This binder is glass frit or fired for sealing! It is decomposed by heating and humidity at a temperature below 100 ml, and only a small amount remains in the fired frit and evaporates. thermal gravitation analysis
sis), approximately 0.0% is present in the fired frit.
3-7.2% nitrocellulose remains.

The solvent used is amyl acetate because it quickly volatilizes from the extruded ribbon and allows the ribbon to be fired more quickly to seal the glass surfaces to be joined. preferable. Ethylene glycol methyl ether is also good ii: 'J, and this λ1 is that.'
] Can be used alone or as a mixture with a highly acid-resistant amyl. Other binder solvents that can be used include ethylene glycinol ethyl ether, methyl amyl acetate-1, J-tylhegysylacetate, and acetic acid n-
These include butyl, isobutyl acetate, sec-butyl acetate, and dicodylene glycol monobutyl etherate.

On the other hand, (11') of the binder used is the amount that determines the ability to fix the sealing glass frit parts as an extrusion (-14 functional paste), and the amount of the sealing glass solid to the binder solution is Pb3O4 including
Usually about 10:7-12. g: range of /.

PbaO4 is about 0. The preferred range is about 0.25 to 0.7%, with 0.5% giving no consistently good results. /1.5% or more is used, the solder composition must be adjusted in consideration of PbQ formed by the reduction of Pb3O4. It is Pb3
BaO2 can also be used in place of the reference example and 1+, and similarly the oxygen content in the sealing glass is higher than the low oxide of the metal. It is also possible to use other metal oxides that have a high content or can form part of the opaque sealing glass without materially impairing its basic properties. . B a O2 reduces to BaO while the glass solder is in the firing humidity range and forms an opaque seal. BaO due to reducing atmosphere and oxygen-containing gas formed during face plate firing step
The reduction of 2 also prevents the dielectric breakdown caused by the formation of metallic lead, since the gold of Pi)0 inhibits the simultaneous reduction to lead.

The metal oxide with a high oxygen content, such as Pb304, must be stable within the 7-grade range in which the sealing glass is fired, and must not decompose at this temperature. This is important because it must be in the following form: 1) Slowly reduced to PbO by an aqueous atmosphere or a 41 organic gas. If it is stored in [this] or [decomposition], it will not be able to perform its intended function.The firing temperature of pbo-containing Karasu Kenta is in the range of about goo-g o'C. However, in many cases such a glass has sufficient fluidity and an opaque seal (112.!;
~1143"c λ]O Pb30+ is SO
It is stable at temperatures of 0 and 0.

/9 Years and months on Otsu, 9 on the 27th. v Revision A' Also, in U.S. Patent No. 337096 B, 11" between two types of glass parts
The use of oxidizing agents in the glass solder to form joints is not indicated, and the oxidizing agents are some kind of adulterant, such as fibers, metal powder, etc., that are mixed in during the normal manufacturing process. It must decompose quickly to release free oxygen for burning off the material. Stiff additives are also formed by the decomposition of lead-containing components of the frit.
It also combines with all gold-shaped lead. If metal powder such as aluminum is mixed in the cement, it will be oxidized to A, 1203. The reference examples listed above are the sealing space, which is fired immediately after introducing it.
Since Pb3O4 must remain even when placed at a temperature of
This is essentially different from No. 6 O.

The dielectric strength improvement effect due to the presence of Pb3O4 itself in combination with a small amount of hydroxypropyl cellulose is evident from the following take.

Average Volt/mil (Average Volt 10, 00.234Z
C1n)/Reference example/Crow Hanta 7
20.2 #Example/Crow Hantanohinter A
380 Binter A is a 2% solution of nitrocellulose in amyl acetate.

Binder B is binder AqS% and ff1 of the equidistant part
ii Contains 5% of a 1% solution of M amyl and ethylene glycol methyl ether cellulose.

Hydroxypropylcellulose is. 082 layers? % vehicle.

In the above example, hydroxypropylcellulose is used with nitrocellulose. , vehicle 0. /9.
! r~/. ．． When the vehicle is used only as a binder, the vehicle contains 7.3%
・Contains j heavy use%. In particular, the vehicle in the above example comprises the following components (% by weight): Hydroxypropylcellulose OJ93~
7.2 Nitrocellulose 0. Dogu S
9Amyl acetate 83.5 ~9 Otsu.
l/-3 ethylene glycol methyl ether, 2
1+! ~/L+ and hydroxypropyl cellulose /. 3～j
Amyl acetate guar, 5-'19.3 Ethylene glycol methyl ether I17.4-'1
It is clear that 9.3 pb304 and BaO2 are the two most useful reference metal oxides that substantially suppress the chemical content of pbo in sealing glasses containing pb. A] Second ff' of the reference example of the inorganic oxide
4 contains a metal oxide that has a heat content W (temperature IJ) of about II-OO'C or higher.Representatives of the compounds of this !
l Fe304+ CuO, Cu2U and Tl2O
It is 3. Another group of oxides as a reference example is PbO, which is less effective than the first and second groups.
It has been revealed that the video that suppresses the morphological retroactive origin has been completely cured. This third group of oxides is a compound with a relatively high fluorine content (i.e., a higher number of oxygen atoms than the oxides of the first and second groups) or a relatively high melting point (
that is, with respect to the firing temperature of the sealing glass used), or a combination of factors. An example of the third group of oxides is Sb205.T
(!02 + Ta205 + Nb20r+ + V
2O5 and CeO2.

Another compound in the third group is 11i203.

Although this compound is not as effective as lil among the third UYs, it does show some effects.

Part 2 of the effect is visible! YI7) Oxide is goo
1', by a compound having a heat content tts humidity lower than 'c'? Signs are given. Among this group is AS20.
There are 5.

These compounds work by a different mechanism than the compounds described above. The compounds of the tth group decompose to produce M-oxygen within the temperature range during which the Sole glass frit is fired.

In addition to oxides, it has also been found that inorganic nitrates actually inhibit the chemical reduction of pbo in pbo-containing sealing glasses. This nitrate can be divided into three groups. The first group produced the most pronounced effect, with a decomposition Δ1 degree of about 3oO~B. O'C1 melting point approximately 360~
It is characterized by compounds having 2 t'c, and water of hydration. Examples of this group of compounds are Ca(NO3)2
・11H2o:Zn(No3)2・Otsu H20; L
a (NO3) a・Otsu H20; B i (NOa)
2 ・ 5H20iCe (NOs ) 3 ・ Otsu H
hOiNi (NO3)2 ・Otsu H20; and Cd
(NO3)2·llH2O. The second group of nitrates produces results comparable to the compounds of the first group of nitrates, or this second group has a melting point lower than the firing flux of the PbO-containing sealing glass, and the PbO - It is also characterized as A because it is a compound that has a higher thermal decomposition humidity than the firing humidity of the sealing glass it contains. Examples of compounds falling into this second group are L i No a and A gNo 3
It is. The third group of nitrates, although less effective than the first and second groups, has a melting point of about Il/110~
3q, 2°C.

Examples of this group of compounds -, C3NO3, Pb(NOa)2
and Ba(NOs)2.

fm (fi 1) Another group of salts has been found to be particularly effective in sealing glass pastes containing cellulose binders. This group has a fiber softening point of sealing glass of about 7300.
HNO is thermally decomposed at temperatures between
It is characterized by being a nitrate that produces a.

An example of such a compound is Cu(NO3)2.3H20
and B 1o(NOa) .H2O. Although the mechanism of action has not been completely elucidated, these compounds have I(
Emit NOs and knead cellulose high > Gut anti+
1i1; to produce a nitrocellulose binder (i.e. the cellulose binder has a nitro group)
Theorizes. The nitrocellulose binder is p
By chemically reducing PbO in bo-containing Ti sealing glass,
For example, it is known that hydroxypropyl cellulose binders do not cause problems.

Another group of inorganic compounds that can substantially inhibit the chemical reduction of Pbo in PbO-containing sealing glasses are metal hydroxides, which act like oxides. The compound J contained in this Jl is thermally stable at the temperature at which the sealing glass is fired and does not decompose thermally within the firing humidity range, but reacts when placed in the reducing state that exists during the firing of the sealing glass. It is a hydroxide. Examples include LiOHi LiOH・H2O; Zr(OH)
4 i Zro2HWho ; Ba(Of-I) 2
:Ba(OH)2.llH2O. In the case of hydroxides, water of hydration is considered to have no significant effect. For example, substantially anhydrous lithium hydroxide and hydrated lithium hydroxide exhibit substantially the same apparent effects.

A less effective group of inorganic hydroxides are hydroxides that decompose thermally at humidity lower than the temperature at which sealing glass or glass surfaces are sealed together. As an example of a stiff compound, M
There is g(OH)2.

Another seven inorganic compounds that have been shown to substantially suppress the chemical reduction of PbO in sealing glass containing PbO stone.
One group comprises carbonates of metals.

Corn carbonates are characterized by compounds that produce carbon dioxide at temperatures above the firing humidity of the sealing glass. Examples of such compounds are MgCO3, which have a significant and pronounced effect on the body.

Another group of carbonates that are less effective than magnesium carbonate are CdC0a and Znco a. Compounds in this second group lose carbon dioxide within a temperature range of about 300-3000°C, and for example 1looo°C.
It shows a very obvious effect when used in a PbO-containing sealing glass having a relatively low firing temperature of 100% or less.

It is clear that inorganic oxygen-containing chlorine compounds are also suitable additives for PbO-containing sealing glass frits. Inorganic oxygen-containing halogen compounds may also be used, but preferably the compounds have been thermally decomposed once at a temperature equal to or higher than the firing temperature of the sealing glass. Particularly preferred are perchlorates, especially ClO4.

Another group of inorganic additives that have proven useful are dichromates. In particular, an effective amount of 2Cr
207 are available. Generally, dichromates can be used which have a decomposition temperature of not more than about -100°C or not more than about +700°C with respect to the firing temperature of the )) bo-containing sealing glass.

Another group of inorganic additives are pyrosulfates and perocunesulfates that have a high oxygen content (e.g., about 7-g oxygen atoms) and preferably have thermal decomposition temperatures higher than about 300"C. The compounds K2S2O7 and 2S208 were found to have a clear effect.

Unexpectedly, P 205 is about q o o'
It is clear that this method does not work properly on PbO-containing solder glass having a firing temperature of c or more. This means that
Since P2O5 sublimes at about 300°C, it is suggested that the use of materials that sublimate at temperatures below the firing crystallinity of Kenbuko Karasu should be avoided.

PbO-containing glass sealing frits were tested to determine the ability of several additives to inhibit chemical reduction of the PbO component when glass sealing frits are mixed with a vehicle to form a paste and then fired. Completed a series of tests. Additives are shown in column / of Table 1. The additive fidget is mixed with the sealing glass frit and mixed into individual parts of the sealing glass frit]
The total additive weight percentage is 0. ,! %, 01g%, /
, j% or 3%. A portion of the resulting sample was mixed with sufficient vehicle to form a paste. Seven samples of each additive-sealing glass frit paste, with additive concentrations not shown, were prepared at separate temperatures: IIoo'c, ttso''C, or 5-23
'C fired. The reason why Konera's humidity range was chosen is that
The humidity in these areas is very low when it comes to color television reception.

This is because it falls within the typical range of work in storage manufacturing. Below is a summary of the operations performed in conducting the test.

Microscope slides were prepared by depositing typical cathode ray tube sealing glass in paste form with and without the additive 1 described above. The sealing glass (also referred to as "Pabase glass" in this specification) is
The PbO-containing sealing glass had one of the following compositions with oxide content nl expressed in heavy FW%.

Glass A Glass B PbO7! ; g'1lZnO/2
, Otsu 2.78203 g・3
/2・3SiCh 2-/
0.1lBa0. 20-B These base glasses were sealing glass frits with coarse particles removed by sieving; total particles were substantially smaller than 200 mesh.

The baseline color after firing of the base glass sample (
Deionized water was used as the vehicle to establish the base 1ine color) applied to each slide.

Another 7 base glasses containing additives o, g% by weight
One sample was applied to each slide to determine the effect of additives on the base glass.

A sealing color paste was made by mixing 92 parts by weight of base glass and gram weight of vehicle.

The vehicle was 96% nitrocellulose solution (7.2% nitrocellulose by weight in amyl acetate), and D
Owanol EM consisted of a solution containing 1.327% by weight of hydroxypropyl cellulose having a molecular weight of about 60,000 mm and amyl acetate.

These pastes were prepared by stirring a small amount of base glass and an appropriate amount of vehicle on a glass plate.

Another paste is Nikkura λ] which contains additives, a base glass and a hydroxypropylcellulose-nitro7rulose vehicle. The additive is/is intended to inhibit the chemical reduction of pbo. ] and the paste is in Paint Shaker (Paint Shaker).
The mixture was prepared by mixing the base glass and the additives in a small V (int 5 haker) with a hydroxypropylcellulose nitrocellulose vehicle. The weight concentration is OL, 2%, 09g%.

Seal River glass pastes were made containing /, 5% or 3% additives.

Each base plate was transferred to a previously cleaned glass slide by wiping with acetone. Samples of the paste were applied by depositing randomly sized drops onto a glass slide using a spatula. The paste is heated at a temperature of about 720°F (49°C) for about 3 hours.
Dry by heating in air.

Just like sealing glass to a glass slide,
Each glass slide was fired. This was done through three different firing cycles or by varying the peak temperature. The firing cycle consists of heating the glass slide in air at a peak humidity of 1°C/min;
Including holding at peak altitude for 3j minutes and cooling to room temperature with a humidity drop at a rate of 2'C/min. The peak temperature was qoooc, +, to'c or S25°C. The test results for Konera are shown in Table 1. It must be recognized that the purpose of the konela test is to know the effect of various vehicles and additives on the chemical reduction of PbO. be understood by doing. The formation of free vessels or low oxidation state lead during firing is not characterized by a gray-black color in the fired sample unless the additive is black or gray.

Good results were obtained for sample s41. It cannot be obtained when S and B are pale or different in color than the sample, 463. The results in Table I are based on visual observation. Dots or tabs mainly indicate incomplete mixing. A more uniform shade will result from a more uniform mixing of the frit and powder additives.

292 In addition to the compounds shown in Table ■, the following additional results were observed. Cupric oxide is 0.2%, 00g% and 8S
Cupric oxide, which gave very good results at a concentration of 0%, has a clear effect, but cupric oxide is not as effective.

Ferric oxide gives excellent results in Glass Binder A even at concentrations as low as 0.2%. Triiron tetraoxide (FeaO+
) shows a clear effect, although it is not as effective as ferric oxide. Zr(OI4)4 and Zr02・H2O
Both are effective at high concentrations, for example at 3% addition level. At a concentration of 7.3% the latter compound exhibits a somewhat orange-yellow hue. While Mg (OID 2) shows a fairly pronounced effect, the other hydroxides tested are not as effective.

Among other nitrates tested, B10(NO3) H2
O is 0.2%, 0. % and/or 3% gave excellent results. Fired samples containing this additive exhibited a white color. 0u(NOa)2.3H20 is sealing glass B, 0.2%, 01g% and/or 5%
gave very good results at a concentration of . Potassium pyrosulfate is
Either sealing glass A or sealing glass B was fired at ≠00°C and tlsooC to give 0, g% and /. Very good results were given with an additive concentration of 5%. Potassium belloxonisulfate was somewhat less effective than potassium pyrosulfate. The potassium belloxonisulfate containing sample exhibited some white dots in the gray matrix.

Another compound tested was boric acid (I(31303
), which produced a fairly good color effect. However, this compound does not contain Pb in PbO containing sealing glass.
It is not among the best compounds for inhibiting the chemical reduction of O.

It is noted that the effectiveness of hydrated compounds is surprising to those skilled in the art. It is expected that compounds containing water of hydration will cause bubbles in fired samples of sealing glass. In contrast, some hydrated additives have been shown to be very effective in suppressing the chemical reduction of Pi:+O without resulting in the formation of bubbles in the fired sealing glass. It was made clear.

Testing of the surface finish shows that Base Glass A, applied to glass slides using only deionized water as the vehicle, has a yellow color after firing. In Glass B, on the contrary, a gray or black tint is obtained in the absence of cellulose binder. This is glass B rather than glass A.
The presence of more PbO at , results in the reduction of this Pbo to free vessels. Therefore, this is not the case with glass B since there is not much PbO reduction in base glass A in the absence of an organic cellulose-containing vehicle.

Pb in a frit comprising glass B.

The issue of restitution is more important. Those with additives are those containing glass B, which are more effective, but
It will become clear from this. The use of glass B in the TV industry is
Due to the high PbO content, it may be advantageous that it can be fired at low temperatures.

It can be seen from Table 1 that when the glass contains a cellulose binder, some PbO reduction occurs as seen by the black or gray color of sample A3.

In some cases, the gray or black tint is more apparent when the glass slide is viewed from its back side.

As mentioned above, when comparing these samples with samples Tsutagu, 5 and O, it is clear that the additive has a clear effect on suppressing the chemical reduction of PbO.

The present invention provides a method for sealing two glass surfaces together.
In a sealing glass frit containing PbO mixed with a powder additive, when the sealing glass is fired under reducing conditions at a temperature sufficient to seal the glass surfaces together, the PbO is prevented from being reduced by adding a powder additive into the sealing glass frit in an amount sufficient to prevent reduction of PbO in the sealing glass upon sealing under reducing conditions. (A) a cationic hydroxide, the hydroxide being thermally resistant at the temperature at which the sealing glass frit seals the two glass surfaces together; stable; the hydroxide is capable of being chemically reduced when subjected to reducing conditions; the hydroxide is Li0H2LiOH4hO2
Zr(OH)4. Ba(OH)2・g'H20 and Z
Selected from the group consisting of rCh.
Otsu ~ 2 Otsu + 'c, and an inorganic nitrate containing hydration water, the nitrate is C! a (NOa) 24H20+
Zn (N'03) 2 ・Otsu H20, La (No3
)3・OtsuH20+Bi (NOa)2・3khOr
C! e(NOa)3・Otsu]-(20+Nj (NOa)
) 2 ・Otsu H20 and CD (No3) 2・III (
selected from the group consisting of 20; (Q approximately/evening 0°
An inorganic nitrate that can be thermally decomposed between Cu (No.
3) selected from the group consisting of 2.3H2o and B10(NO3).H2O; (to) such that the sealing glass frit produces carbon dioxide at or above the temperature at which the two glass surfaces are sealed together; A thermally decomposable inorganic carbonate, said carbonate being MgcOa i (g)) An inorganic oxygen-containing chlorine compound having a thermal decomposition temperature equal to or higher than the temperature at which the sealing glass seals two glass surfaces together; Containing chlorine compounds are ■ (side Q4
PbO-containing sealing glass frit, characterized in that the powder additive is miscible with the fired sealing glass.

The powder and its product after firing are miscible with the fired sealing glass.

The powder is present in the frit in an amount sufficient to prevent chemical reduction of the PbO during sealing of the PbO sealing glass under reducing conditions. Typically the powder is present in the frit in an amount of about 0.7 to 3% by weight, but preferably about 0.2 to 3% by weight.
, present at 5% by weight. If a smaller proportion were used, it would be necessary to adjust the solder glass composition to account for the powder and the product obtained after firing.

The sealing glass paste may contain an amount of organic or inorganic acid sufficient to prevent gelling of the paste upon aging. This can be accomplished by adding enough acid to keep the I)H acidic in the paste. Usually only a small addition of solder is required. A particularly preferred acid is citric acid. It has been confirmed that the addition of about 70~S/S of citric acid per sealing glass frit 1110Abs (2001C9) is effective in preventing gel formation. The use of such acids is advantageous in that it allows precise control of the bead width and allows the use of more consistent dispensing pressure when the sealing glass is applied to the surfaces to be sealed together. It is. other acids,
For example tartaric acid, phosphoric acid and sulfuric acid can also be used. Optimal amounts can be determined with a minimum of experimentation.

Agent's name: Kawahara 1) - Ho 297

Claims (1)

[Claims] A sealing glass frit containing PbO mixed with a powder additive for sealing two glass surfaces together. When fired under reducing conditions with sufficient humidity to
PB in the sealing glass. PBO in the sealing glass is injected in an amount sufficient to prevent reduction of pbo in the sealing glass during sealing under the reducing conditions. (A) a cationic hydroxide; The hydroxide is capable of being chemically reduced under reducing conditions; the hydroxide is Li0HIIjOH-H2
O+Zr(OH)a, Ba(OH)2・J
selected from the group consisting of lhO and ZrO2/XH2O; (B) pyrolysis humidity of about 30 to 000;
The nitrate 601JN is an inorganic material having a melting point of about 36 to 2°C and containing water of hydration.
NO3) 21'H201Zn (NO3) 2 ・Otsu H20, La (NO3) 3 ・Otsu Tl2O, Bi (
NOs )2 ・3H20,Ce (NO3)3 ・OtsuT-'hO9Ni (NO3)2・OtsuH, 20 and C
d(NO3) So/IH, selected from the group consisting of 20]
(C) approx./30°C and sealing crow f, t
, t(I), an unmyelinated nitrate #salt that can be thermally decomposed to produce HNO3 between the softening point of Cu(NO3)
23H20 and BIO(N03).1 (selected from the group consisting of 20; (E) an inorganic oxygen-containing chlorine compound having a pyrolysis humidity above the temperature at which the sealing glass seals two glass surfaces together; The compound is KClO4
a patented PbO-containing J, characterized in that the powder additive is miscible with the fired sealing glass;
゛How to use the seal.