JPS60108345A - Transparent enamel frit having low softening point - Google Patents

Abstract

PURPOSE:The titled enamel frit, consisting of SiO2, B2O3, Na2O, K2O, Li2O, CaO, BaO, Al2O3, ZrO2, F2, MoO3, MnO2 and Fe2O3, and having improved dipping characteristics, water resistance and adhesion under low-grade treating conditions. CONSTITUTION:An enamel frit, prepared by incorporating 32-45wt% SiO2 with 7-20wt% B2O3, 14-22wt% Na2O, 0.4-5wt% K2O, 0.3-2wt% Li2O, 1.5-15wt% CaO, 1.5-15wt% BaO, 0.5-5wt% Al2O3, 0.5-4.5wt% ZrO2, 2-9wt% F2, 0.4- 5wt% MoO3, 0.1-2wt% MnO2, 0.3-2wt% Fe2O3 and if necessary 0.1-5wt% ZnO and <=3wt% at least one component selected from MgO, SrO, TiO2, SnO2 and V2O5, and melting the resultant mixture under heating.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an enamel frit that can be fired at low temperatures, and brings about resource and energy savings in enamel processing.

Structures of conventional examples and their problems Generally, the baking temperature of enameled steel plates is 800 to 870°C, which is higher than the A1 transformation point (723°C) of steel, so during baking, the iron crystal type transforms from α iron to γ iron. The steel plate is easily deformed due to thermal distortion, and the dimensional accuracy after firing is poor, resulting in a high defective rate. Therefore, the plate thickness must be increased. If the steel plate is heated to a high temperature, hydrogen gas etc. adsorbed or occluded in the steel plate will be significantly generated. Moisture that is still slipping or on the steel plate reacts with carbon in the steel plate in the firing temperature range to generate carbon dioxide gas, which tends to cause defects such as bubbles and pinholes on the enamel surface.

For example, if the inner wall of an oven is baked with a hollow roller at 800 to 870°C on a steel plate with a thickness of 0.6ffff, the molded product will be greatly deformed (and there will be many bubbles, pinholes, etc., so the defective rate will be high. , A1 If enamel can be fired at a low temperature below the transformation point, there will be less deformation due to thermal distortion, and there will be fewer defects such as bubbles and pinholes due to gas generation, making it possible to use thin plates with a thickness of about 0.4 mm. Furthermore, it is easy to enamel objects with complex shapes.

In recent years, resource conservation and energy conservation have become important issues. By lowering the firing temperature of the enamel, fuel costs can be reduced, and by allowing the use of thin plates, material costs for the base material can be reduced.

Although the low-melt enamel processing technology that is fired at low temperatures has excellent advantages, it still has insufficient properties to replace the current general enamel that is fired at high temperatures. It is something.

One of the reasons for this is that enamel is required to have surface protection functions such as heat resistance and corrosion resistance as well as decorative functions, but conventional low melting point lead frits do not have both functions. Because there was nothing to be satisfied with.

Among these, in particular, requirements for decorative functions include the surface condition and gloss of the enamel surface, as well as the ability to develop various colors and stability.

Conventional low-melting enamel frits have had problems with the stability of two color tones.

Therefore, as described in Japanese Patent Application No. 57-19243, the present inventors have developed a chemically stable material that can be fired below the A1 transformation point of iron or iron-based alloys, can be colored in all tones, and is chemically stable. Low softening point enamel frit'
developed. However, they still had the following problems.

■ Long-term storage properties of enamel slips ■ Dipping characteristics ■ Adhesion in low-grade pretreatment (when pickling loss value and nickel treatment adhesion amount are extremely low) ■ Low softening point of enamel slips ■ Long-term storage properties of enamel slips used in enamel frits The problems related to this are as follows. In order to lower the softening temperature of enamel frit, it is necessary to add alkaline components (N&20, K2O, Li2O, etc.) to the glass, and compared to conventional general enamel frits, increasing the amount of alkali components is avoided. I can't do it. Using the low softening point enamel frit of the earlier application,
When a enamel slip is prepared and stored for a long period of time, alkaline components gradually dissolve from the glass frit, adversely affecting the slip. When this slip that has been stored for a long period of time is glazed and fired, it becomes more enamel, has a new skin, and cracks.

Occurrence of serious defects such as Koppa head was observed.

The dipping characteristic (2) is a problem with the glazing method, that is, the dipping method in which objects are immersed in the slip to apply the glaze, and is due to the chikuntropic nature of the slip.

The fluidity of the glass frit is an important point.

The low softening point enamel frit of the prior application is mainly a glass frit for the spray method, and when the dip method is used, pinholes, sink marks, etc. occur in the enamel layer, which is not desirable.

The problem regarding the adhesion of (2) is as follows.

This prevents the single layer of enamel from adhering firmly to the base metal.

Thermal oxidation of the base metal that occurs during the formation process has a large effect. For example, in the case of a steel plate enamel, iron oxide formed during the firing process is arbitrarily diffused into the enamel layer, and the enamel layer is strongly adhered to the metal due to so-called chemical bonding.

In the case of general enamel, the firing temperature is extremely high, over 800°C, so the above-mentioned iron oxides are often produced.

This oxide dissolves and diffuses into the enamel layer, and the adhesion between the enamel layers becomes stronger. On the other hand, in the case of a low softening point enamel frit, since it is fired at a temperature approximately 150° C. lower than that of general enamel, the amount of the above-mentioned iron oxide produced is small, and the adhesion is inferior to that of general enamel.

As a result of considering improvement measures, it was found that by increasing the pretreatment conditions, such as the pickling loss value or the amount of nickel 41, even if the low softening point enamel frit of the earlier application was used, adhesion comparable to that of general enamel could be achieved. It has been confirmed that you can get it. However, in order to increase the pickling loss value or the amount of nickel deposited, it is necessary to increase the pickling treatment time or the nickel treatment time, which poses a problem from the viewpoint of productivity and cost efficiency.

Therefore, in order to solve such problems, the present inventors devised a low softening point hollow frit having the following composition.

That is, the following are the examples.

5i02 32 to 46 Weight 8203 7 to 20 Weight Na2O14 to 22 Weight % to 20o・4 to 6 Weight % Li2Oo, 3-2 Weight % CaO 1,6 to 16 Weight % to 8 1, 5 to 16 Weight A12o 3 0.5~! 5 Weight ZrO2o, e
s -4,5 weight class F22 ~ 9 weight class MOO5o,4- ts tft% MnO22 wt% or less 0r205 2 wt% or less MnO2+ Cr2O3 = 0.1-2 wt% low softening point enamel frit.

Furthermore, in order to impart water resistance to this frit, the present inventors devised a low softening point hollow frit having the following composition. That is, the following is 08i02 32
~46 Weight class B2O57~20 Weight class Na2014 ~22 Weight% 20 0.4~5 Weight class Li2O0,3~2 Weight class CaO1,6~16 Weight class ZrO2o, s~4.6 Weight class F2 2~9 Weight % MoO30.4-6 weight % Mn02 2 weight % or less Cr2O5 2 weight % or less MnO2+ (ir203 0.1-2 weight % low softening point enamel frit.

However, these frits have a dark red color when using MnO2, and a pale green color when using Cr2O5.

1. If MnO2 and Cr2O3 are used together, the color will be even darker.

Therefore 1. It has been found that the above frit has a problem in that it cannot be used for bright, vividly colored enamel. Therefore, improvement was sought.

Purpose of the Invention The present invention enables firing at a temperature below the A1 transformation point (723°C) of steel, allows for long-term storage of slips, has excellent dipping properties, water resistance, and adhesion in low-grade processing, and further improves the surface The purpose of the present invention is to provide a low softening point transparent enamel frit which is smooth and can be made into a bright and vividly colored enamel.

Structure of the Invention The low softening point transparent enamel frit of the present invention contains, as essential components, 5i0232~46% by weight (hereinafter simply referred to as %FEW) + BzO5T~20%, N5L2014~22
%, K2O0-4~5%, Li200-3~2%, Ca
O1,5~15% + BaO1,6~15% +
Al2O30-6~5% +MnO20-1~2
% and Fe2O30.3-2%.

5. Description of Examples First, the reason for limiting the composition range of the components constituting the frit of the present invention will be explained.

1) 5i02. B2O3 components 5i02 and B2O3 are important oxides as glass-forming oxides, and the proportions of 5i02 and B2O5 greatly affect the thermal expansion coefficient, softening point, slip life/dipping characteristics, and water resistance of enamel.

When lowering the melting point of glass, it is necessary to reduce 5i02, but the amount is determined based on the relationship with other components.

In the frit of the present invention, sio, 232-45%.

B2O37-20%. When Si02 is less than 32%, the solubility in water increases, and the life characteristics of slip,
The water resistance of the enamel deteriorates. On the other hand, if you exceed 46 cm,
It becomes impossible to fire at low temperatures.

However, if B2O5 is less than 7 inches, the softening temperature will be high and there will be problems with the gloss and dipping properties of the enamel surface, which is not preferable. On the other hand, if the ratio exceeds 20, the slip life characteristics become particularly poor.

It is also unfavorable for the water resistance of the enamel.

In the above range, the ratio of 5i02 and B2O3 %5i02/
It is desirable that B2O3 is 2 to 6. Namely.

If it is less than 2, it is particularly unfavorable for the life of the slip and the water resistance of the enamel, and if it exceeds 6, the softening point will rise and the dipping properties will deteriorate, and baking will not be possible below 723°C, resulting in loss of gloss.

2) F<20 component The R2O component here refers to Na2O, which is an alkaline component.

Represents K2O and Li2O. The composition range in the present invention is N
a2O 14-22%, K20ka 0.4-6%, Li
2O is in the range of 0.3 to 2. The R2O component is a strong melting agent and is an important component that increases the fluidity of molten glass and lowers the softening point in frits. However, R
Depending on the amount of 2O component used, the resistance to aqueous solutions is reduced and the resistance to weathering is reduced. It is also a component that has an important effect on the dipping characteristics, and it is also a component that greatly changes the expansion rate of the frit.

Among these R2O components, the effects of lowering the softening point are as follows:
The order is Li2O:> Na2O) K2O (7), and in order to obtain a low softening point frit with excellent slip life and dipping characteristics, the important issue is not only the amount of R20 but also which components to select. .

Next, regarding the content ratio of each component, although the Na2O component has the effect of increasing the solubility of the frit, it is a component that has an adverse effect on the chemical durability, slip life, and dipping characteristics of the frit.

14 in terms of surface condition, gloss, water resistance, and slip life.
A range of 22q6 to 22q6 is preferred.

The K20 component is an effective component that not only increases the solubility but also increases the gloss of the hollow. K2O is preferably 0.4 to 6%. If it is less than 0.4%, it will not be possible to obtain a higher level of gloss, and if it is more than 5%, it will have a large effect on chemical durability and slip life, which is not preferable.

L120 component is mentioned above (7) N”L20 r K20
It is the most effective component in increasing the easy solubility of frit compared to other components, and can significantly lower the softening point even when added in a small amount, and is an essential component of the present invention. However, since it is a component that tends to have an adverse effect on the gloss 2 surface condition, care must be taken regarding the amount added.

As the amount of Li2O increases, the fluidity of the frit decreases greatly, but when it exceeds 2%, the surface condition of the hollow layer, especially the occurrence of orange skin, becomes noticeable.

It can be seen that the gloss decreases accordingly. From these points, it is appropriate for Li2O to be 0.3 to 2%.

In addition, the sum of the contents of Na2O, K2O, and Li2O (Na2
0+ to 20+Li2O) is preferably 17 to 26. That is, if it is less than 17%, the softening temperature of the frit will be high (V), the gloss of the enamel and dipping properties will be poor, and if it exceeds 25%, the life of the slip will be shortened.

The water resistance of the enamel deteriorates.

The R'0 component here is an alkaline earth metal oxide,
In the present invention, CaO and BaO are essential components. R
Although the O component is not an alkali metal oxide, it acts as a melting agent and has the property of lowering the softening point of the frit. Still elastic modulus.

Improves mechanical properties such as tensile strength.

Furthermore, what is significantly different from alkali metal oxides is that the addition of alkaline earth metal oxides improves the water resistance of the frit.
It has the property of improving chemical durability.

The behavior of each component will be explained in more detail below.

The CaO component tends to maintain the chikuntropic properties of the slip, and tends to improve the life characteristics of the slip or the workability of dipping, and is an essential component of the enamel frit of the present invention.

If the CaO content is less than 1.6, it is not preferable because it affects the life characteristics of the slip and goes against the purpose of the present invention. vice versa,
If it exceeds 15%, the glass content and the
B-type audio pin attachment 11F is not desirable. Also, the luster of the enamel decreases.

For the above reasons, the CaO content is 1.6 to 16%.

Since the GhO component is relatively inexpensive compared to other components,
In terms of quantity, adding a large amount is advantageous in terms of cost.

BaO component [Although not as strong as the R2O component, it is a component that improves the fluidity of the glass frit.Also, even if the amount added is increased, the alkaline component does not deteriorate the water resistance, and the glass frit of the present invention It is an effective ingredient. However, since the %BaO component tends to corrode the melting crucible, it is necessary to pay attention to the amount added.

If the BaO content was less than 1.5%, an enamel frit that met the object of the present invention could not be obtained, and dip glazing could not provide a preferable surface condition. On the other hand, if it exceeds 16%, the characteristics meet the objectives of the present invention, but the crucible is severely eroded, which is not desirable from an industrial standpoint.

For the following reasons, the B&0 component is preferably in the range of 1.6 to 15%. The BaO component is relatively expensive and should be kept as small as possible from the viewpoint of crucible erosion.

Furthermore, when the BaO component is used together with CaO, the fluidity of the glass frit is particularly excellent, and a frit suitable for dipping glazing can be obtained. Ca
The preferred range of the sum of O and BaO contents is 9 to 21 times. If the ratio is less than 9, the dipping characteristics are unfavorable;
If the content exceeds 1% gold, the life characteristics of the slip deteriorate.

4) Intermediate oxide component In the present invention, Al2O3,
ZrO2 is an essential component. These components are effective in reducing the amount of frit dissolved in hot water or acidic solutions. However, adding too much will raise the softening point of the frit.

The selection of the two types of amounts is important because it reduces the gloss or surface condition of the enamel surface.

The Al2O5 component is a component that particularly improves the chemical durability of the frit, and is an essential component for the present invention. Al2O
If the content of the three components is less than 0.5%, the water resistance of the frit deteriorates, and it also adversely affects the life characteristics of the slip or the water resistance of the enamel, which is not preferable. On the other hand, if it exceeds 6%, the fluidity of the frit decreases, making it unsuitable for dipping glazing, which is contrary to the purpose of the present invention, and is not preferred.

For the above reasons, the Al2O6 component is preferably in the range of 0.5 to 5%.

Although the ZrO2 component is not a component that improves the chemical durability of the frit like the Al2O5 component, it is an essential component for the frit of the present invention from the viewpoint of corrosion in the zircon melting furnace.

Glass melting furnaces are usually made of zircon to ensure long-term use. In order to prevent corrosion of this zircon melting furnace, it is preferable that the glass frit contains a ZrO2 component.

When the ZrO2 content is less than 0.6, the effect of preventing corrosion of the zircon melting furnace is small. On the other hand, if you exceed the 45th section,
The fluidity of the frit decreases, and for the reasons mentioned above, Zr
It is necessary to keep the O2 component in the range of 6 to 4.6.

6) F2 component The F2 component is generally an important component as an indirect emulsifier and a melting agent.

In the present invention, (d, Fz acid components 2 to 9 are used).

Although the F2 component has the property of scattering by 30 to 50% of the theoretical amount when producing the frit, the optimum range of the F2 component in the present invention is the amount of F2 contained in the produced frit.

If the amount of F2 component is less than 2 coefficients, the fluidity of the glass necessary for dipping properties cannot be obtained, which is not preferable. If the ratio exceeds 9, numerous gas bubbles will be generated on the enamel surface, resulting in poor appearance, and at the same time, the crucible will be easily eroded during frit production, which is industrially disadvantageous.

6) Adhesive oxide It is said that cobalt oxide is usually effective as an adhesive oxide in frits for lining general enamel. , C00 is expensive, so □NiO or [MnO
There are many examples where it is used in combination with 2.

In the frit composition range of the present invention, MoO3+NiO
, the adhesion of the enamel when Coo is used alone is P
Figure 1 shows the HI standard adhesion rate.

The base material is a 5PCG steel plate with a plate thickness of OEmm, and the pickling loss is 1o.
o mf17'dA, nickel deposition amount 5 Mg/dd
f ari.

The firing conditions for the enamel were 710° C. for 6 minutes, and the enamel film thickness was about 120 μm. 1 is MoO3, 2 is Ni013
(This is the case when ioo was used. Coo was not as effective as is said for general enamel. It is true that the Coo ingredient has excellent adhesion, but the addition of it caused an orange skin to appear on the enamel surface. , undesirable.

In the frit of the present invention, the most effective component for adhesion was MoO5.

The adhesion of enamel is correlated with the loss of pickling of the base material and the amount of nickel deposited. In particular, there is a strong correlation with the amount of nickel deposited. This is because Ni and Fe form local batteries during firing, the surface of the steel sheet is roughened, and the mechanical and chemical bonds between the hollow layer and the steel sheet become stronger.

FIG. 2 shows the relationship between the amount of nickel deposited to ensure a PHI adhesion rate of 90% and the amount of MoO3 added to the frit composition of the present invention. The base material is a 5pc steel plate with a thickness of 0.6mm, the firing conditions are 71oC for 6 minutes, and the enamel film thickness is approximately 120μm.
It is.

When a 5pc steel plate is pre-treated twice, which is a low-grade enamel treatment, the pickling loss is 60 to 260 nitrates/
The amount of nickel deposited is 2 to 61179/dd. Therefore, from FIG. 2, the lower limit of MoO5 is 0.4%.

At 1%, good adhesion can be obtained even with the lowest amount of nickel deposited. The larger the amount of MoO3, the better the adhesion, but the gloss decreases and the life of the slip and water resistance deteriorate. For two reasons, the composition range of MoO3 is 0.4 to 6, preferably 1 to 3.

7) Although a frit with excellent adhesion was obtained by adding the foaming suppressing component MoO3e, a problem occurred in that large bubbles were generated in a convex shape on the surface of the hollow layer.

This phenomenon is MOO! , is 1% or more, and the glass melting time is particularly likely to occur when the glass melting time is short. When fired at a temperature of 690 to 720°C, it foams quickly, and when fired at a temperature of 740°C or higher, it does not foam. However, this is not the firing temperature targeted by the present invention.

This foaming is caused by sublimation of MoO3 or by MoO3 being 0.
It is thought that this may be caused by the release of 2, but the mechanism has not been clarified.

As a result of various studies on suppressing this foaming, we found that MnO2 and c
An effect was observed when adding r20x 'fr.

In this invention, it has become possible to decolorize MnO2. However, it is difficult to erase the color when Cr2O5 is added.

Therefore, in the present invention, MnO2 is added in an amount of 0.1 to 2%. If it exceeds 2 inches, the fluidity of the frit will deteriorate and pinholes or repellents will appear on the enamel surface.

This may cause sink marks, etc.

Mouth A Nroro 1 Punishment ^ Mn02 colors the frit pink or reddish brown. Therefore, this frit cannot be used as a frit for bright and vividly colored enamel.

As a method for eliminating the coloration of MnO2, Fe2O3 is used in the present invention.

The color of the frit when Fe 205 is added alone is MnO
It has a complementary color relationship with 2, and the appearance can be physically erased.

A suitable content of Fe 205 is 0.3 to 2%. If it exceeds 2, the fluidity of the frit will deteriorate.

Although the color cannot be completely erased, it is possible to erase the color until a bright, vivid enamel is possible.

When ZnOf is added to the above basic composition of the present invention.

The water resistance of enamel can be further improved. The water resistance and acid resistance of alkaline earth metal oxides are shown in descending order as follows.

Water resistance ZnO) MgO) (lao) BaO Acid resistance ZnO) CaO) MgO) BaO The ZnO component has the property of improving water resistance and acid resistance as well as increasing gloss. In particular, the water resistance of the hollow layer can be significantly improved even by adding a small amount. ZnO component is 0.1%
If it is less than that, the effect will not be noticeable and it is not preferable. On the contrary, 6
If the temperature is exceeded, the fluidity of the frit will decrease, and in dipping glazes.

A favorable surface condition could not be obtained. For the above reasons, it is necessary that ZnO be in the range of 0.1 to 6%.

When v205 is used in combination with MoO3, a hollow frit with even better adhesion can be obtained without coloring the frit, and it functions as a so-called adhesion improving material. When the content exceeds 3%, the fluidity of the frit deteriorates and a desirable surface condition cannot be obtained.

Furthermore, in the present invention, MgO, SrO, TiO2
It is also possible to contain 5n02k and 5n02k.

MgO, Sr01d, and alkaline earth oxides act as melting agents and have the property of lowering the softening point of the frit. When MgO and SrO are added, ZnO is not
Improves the water resistance of enamel. However, if it exceeds 3 taels, the enamel surface loses its luster and develops an orange skin.

TiO2,5n02 is an intermediate oxide that improves the chemical durability of the frit, although not as much as Al2O5. If it exceeds 3 inches, the fluidity of the frit decreases, making it unsuitable for dipping glaze application.

Next, the raw materials constituting the furinoto of the present invention will be described.

5i02 uses silica powder or feldspar. The main raw materials for B2O3 are borax (Na2B4O7・10H20, N
a2B4O7-4H20), anhydrous borax (Nf!L2B4
07)+boric acid (HsBOs) is used. Na2
O can be obtained from a single component such as 'th2cO5, NaNO3, but borax, Na2Si
F6, cryolite, and feldspar also come in.

K2O (d KNO3, x2GO3) and other VCK2SIF
6 + There is feldspar.

For Li2O, Li2CO3, natural ore spodumene, etc. are used. CaO includes CaCO3, Ca(OH)2, and fluorite.

It also comes from dolomite. BaObaCO3,'
Ba(NO3)2 + BaF2 'fr-Use 0A1
2051'l: In addition to alumina and aluminum hydroxide, cryolite and feldspar particles are also included. It is better to use silkoshi (ZrO2-nsi02) as ZrO2 than ZrO2. This zircon is not only cheap (,ZrO
2 dissolves more easily than 2 alone.

F2 is LiF, NaF, KF, (iaF2
, Na2SiF6, Na3AlF6.

K2SiF6. Examples include BaF2, and all raw materials are determined after considering the amount of cations. Adhesive oxide MoO3
In addition to MoO3, the raw materials are Na2MoO4・2H201 (
NH4)6 Mo 7024 ・4H20, MoS2
, MoSi2.

Zinc white and ZnC0B are used as raw materials for ZnO.

v205 uses v205 alone.

As MgO, Mgco5. In addition to Mho, dolomite can also be used. 5rCC15 is used as SrO.

There are two types of TiO2: anatase type and rutile type, and either type may be used in the present invention. 5n02 uses SnO2 alone.

As MnO2, electrolytic manganese dioxide is a natural Qn02.
, using KMnO4.

As Fe2O3, Fe2O3, red iron oxide, or the like is used.

The raw materials mentioned above are adjusted according to their respective composition ratios.
．． ．． - Nehe's late good fortune, I'm looking for a hundred trips + + +'' ----
Heat and melt at ~1300'C. The heating temperature for 1 hour changes the composition ratio of the final frit components.

It is necessary to manage it well. The time is after dissolving the raw material,
It is important to allow vitrification to proceed for 20 to 40 minutes, stirring as necessary. If kept for a long time, the alkaline components will sublimate.

Try not to make it too long. After melting, the glass is placed in water and rapidly cooled. This is dried to obtain the desired low softening point transparent HO A-frit.

Table 1 shows the low softening point Porro Frino (No.
1 to 9) and comparative example frits (No. 10 to 12) are shown together.

The raw materials for the frit are mixed according to their respective composition ratios. Preparation examples of No. 'I are shown in Table 2.

Table 2 The thoroughly dry mixed raw materials were melted at 1200'C and then held at the same temperature for 30 minutes. After melting, the glass was put into water, rapidly cooled, and dried to obtain a frit.

The frit was milled and mixed with mill additives in a ball mill. Fluffy) IQO-0, 60 parts by weight of frog's eye clay, 60 parts by weight of crushed stone powder (particle size of 326 mS or less), 10 parts by weight of bentonite, 1 part by weight of sodium nitrite, and 20 parts by weight of sky blue pigment.

Further, 600 to 700 parts by weight of water was mixed in an amount suitable for dipping, although it varied depending on the frit composition. Milling was carried out for about 3 hours until the particle size suitable for dipping (5QO
200 mesh of O slip (residue 8-15g),
Pickup value (4,.

A slip of ~6.2 g/1M) was adjusted.

In the slip, pre-treated size 100X10
0 strength, 0.6M thick 5pc steel plate (pickling loss 60g/
dd, nickel adhesion amount 2%/dd).

Glazing was done using the dip method. Then dry, 7
A test plate was prepared by baking at 10°C for 6 minutes.

The characteristics of the test plate thus prepared are shown in Table 3.

The evaluation method in Table 3 was as follows.

1) Coloring of frit A frit that can produce a bright color (sky blue in this case) is indicated by ○, and a frit that produces a cloudy color or a color different from the desired color is indicated by ×.

2) Amount of frit dissolved in hot water The amount of dissolved frit in hot water is 200 to 350 meters per 5 g of frit.
Immerse in 1 oocc of distilled water, boil for 1 hour, remove the supernatant, titrate the eluted alkali component with 0.1N-H2S04 using a methyl orange indicator, and use the amount consumed as a measure of the amount of eluted alkali. did.

o・1N-H2S04 consumption is O-E5ml or less◎
, 0.5 to 1 ml is represented by ○, 1 to 3 ml is represented by , and more than that is represented by ×.

3) Fluidity of the frit The fluidity of the glass frit is as follows: Take 2g of frit with a weight of 200 or less, put it into a mold, form it into a tablet with a diameter of 12.7111m at 1 ton/aj, and place the sample on a steel plate. The sample was heat-treated at 690°C for 6 minutes, and the flow diameter of the sample was measured with a caliper.

Those with a diameter of 20 πm or more are marked with ◎, those with a diameter of 20 to 18 mm are marked with ◯, those with a diameter of 18 to 14 are marked with △, and those with 14 or less questions are marked with ×.

4) Surface condition of the enamel The surface condition of the enamel layer (color bubbles, orange skin, pinholes, cracks, etc.) is the result of visual observation of the enamel surface of the test plate. , indicates that no citrus skin, pinholes, cracks, etc. are observed, and an X mark indicates that discoloration or the above-mentioned defects are observed.

6) Water resistance of enamel The water resistance of enamel is determined by immersing the test plate in hot water at 98°C for 1 hour, and the difference in weight before and after is 6”f/tM or less: ◎, 6 to 10 Vdd. 0゜1o ~ 3o m
f/drRt7) is shown as △, and that of a o mflda or higher is shown as ×.

6) Adhesion of the enamel The adhesion of the enamel was evaluated using a PICI adhesion tester, and those with a value of 10% were ◎ and 90 to io.
Those in the o group are shown as 0%, those in the 70-90 range are shown as △, and those in the 70% range or less are shown as x.

7) Pot life of the slip The slip was placed in a polyethylene container, immersed in a constant temperature water bath at 36° C. for 10 days, and then glazed and fired by the dip method to prepare a sample, and its surface condition was evaluated.

By using the frit of the present invention, it is also possible to use thin steel sheets that could not be used with conventional high-temperature enamels due to thermal distortion and deformation during firing. This will be explained below.

Using Frit No. 1 in Table 1, the thickness of the material was varied and the firing strain was measured and compared with that of a conventional high-temperature type enamel.

The method for measuring firing strain is shown in FIGS. 3 and 4.

As a test plate, a size 60 with a predetermined thickness and no distortion is used.
Using a material 1 of X 300 #Im coated with enamel glaze 2 so that the enamel film thickness is 100μ on both sides, as shown in FIG.
M e= 8mwi)r'5VM 1ri-ishima W
-# Seven Years 1 1iFr Medium/7) Fired at ffi degree,
It was left to cool. When distortion as shown in FIG. 4 occurred, the amount of displacement 4 from the original horizontal line at the center was measured as the amount of distortion. ○ if the value of 4 is less than 1 mm, △ if it is 1 to 3 mm
, 3 or more cases are indicated by ×.

The optimum firing conditions when using the frit of the present invention are 710"C and 5 minutes, while the optimum firing conditions when using conventional high-temperature enamel are 820°C and 5 minutes. These conditions Table 4 shows the relationship between the thickness of each material and firing strain.

Table 4 As is clear from Table 4, with conventional high-temperature firing type enamel heated to 800°C or higher, it is necessary to use a plate with a thickness of 0.6 mm or more due to distortion during firing, and enamel processed products are also available. It naturally becomes heavy.

On the other hand, if the enamel frit of the present invention is used, it can be fired at a temperature below the A1 transformation point of iron, so there is no thermal distortion due to firing.
Thin plate materials such as ff1m, which could not be used with conventional enamel frits, can be used, and the resulting enamel products are lighter.

Furthermore, the firing temperature is approximately 1° to 1° higher than that of conventional enamel.
By lowering the temperature by 50°C, it is possible to save energy during enamel processing, and the fuel consumption required for firing can be reduced by 26 to 36%.

1. It can improve the slip life characteristics, dipping characteristics, water resistance, and adhesion in low-grade processing, which were problems with conventional low-melting enamels.

Furthermore, it is possible to provide a low-softening-point transparent enamel frit with a smooth surface and a bright and vivid color that can be used for practical purposes.

Furthermore, if a frit with a relatively low softening point is used, it can be used not only for enamel steel sheets but also for aluminized steel sheets, and if the expansion coefficient is considered, it can also be used for stainless steel, cast iron, etc. .

Furthermore, the frit of the present invention can be used not only for decoration but also for the purpose of improving the insulation properties of various substrates.

Effect of the invention As described above, the transparent enamel frit of the present invention.

Can be fired at temperatures below 723°C, which is the A1 transformation point of iron, and has a smoother surface than that of a hollow metal.

It has excellent adhesion, water resistance, slip preservability, and dipping properties, making it possible to commercialize lightweight enamel products with bright and vibrant colors.

[Brief explanation of drawings]

Figure 1 is a graph showing the relationship between the amount of adhesion oxide added and the adhesion of enamel. Figure 2 is a graph showing the relationship between the amount of nickel deposited and the amount of M2O3 added to obtain good adhesion. 3 and 4 are cross-sectional views showing the method and results of measuring firing strain during enamel processing. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2: Amount of oxide added (by weight) Figure 2: Amount of Nilaglu added (1%) Procedure amendment April 22, 1980 Patent Application No. 212741, filed in 1988, Title of the invention: Low softening point transparent enamel frit 3 sleeves Relationship with the case of a person who makes corrections Patent application Colonel Address 1006 Kadoma, Kadoma City, Osaka Prefecture Name (
582) Matsushita Electric Industrial Co., Ltd. Representative: Toshihiko Yamashita 4 Agent Address: 6, Matsushita Electric Industrial Co., Ltd., 1006 Oaza Kadoma, Kadoma City, Osaka Prefecture Contents of amendment 0) Specification page 13, line 10 Correct "decrease" to "increase". (2) Change “Plate thickness 06” on page 19, line 6 to “Plate thickness 0.6”.
” I will correct it.

Claims (3)

[Claims] (1) At least 5i02, B2O3, Na2O,
K2O, Li2O. CaO, BaO, Al2O5, ZrO2, F2, M
It is composed of oO3, MnO2 and Fa205, and their content is in the weight ratio f, 5i0232~45%+
82037~20%, Na2014~22% +
K2O0-4~5% + L1200.3~2%, C
aO1.6-16%, BaO1.6-15%. Al2O30.5-6%, ZrO2o,es ~4.5
%, F22~9%, MoO30,4~5%, MnO2
A low softening point transparent enamel frit characterized by having a content of 0.1 to 2% and Fe2030.3 to 2. (2) The low softening point transparent hollow frit according to claim 1, containing 0.1 to 6% by weight of ZnO. (3) MgO, SrO, TiO2, 5n02 and v
Claims 1 or 4 containing at least one component selected from the group consisting of
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