JPS63315535A - Milky frit for dry casting - Google Patents

Abstract

PURPOSE:To enable formation of a milky frit for dry casting having excellent chemical, hot water, thermal shock resistance and opacity, by heat-treating a frit having a specific composition. CONSTITUTION:A milky frit formed by heat-treating a frit [F] having the following composition at 520-630 deg.C for 5-20min. [F] 100pts.wt. first component group and 6.0-30.0pts.wt. second component group. The first component group consists of SiO2, ZrO2, TiO2, B2O3 and R2O and contains 5.0-85.0wt.% total amount of SiO2, ZrO2 and TiO2, 2.0-15.0wt.% ZrO2, 12.0-25.0wt.% TiO2, 5.0-30.0wt.% B2O3 and 5.0-30.0wt.% R2O. The second group component consists of a fluorine component P2O5, Al2O3, ZnO, MgO and BaO and contains 0.5-10 pts.wt. fluorine component, 0.5-10.0pts.wt. P2O5, 0.1-5pts.wt. Al2O3, 0.5-4pts.wt. ZnO, 0.5-4pts.wt. BaO and 0.1-1.5pts.wt. MgO based on 100pts.wt. first component group.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a milky white frit mainly used for dry casting.

Conventionally, it has been widely used as a material for so-called cast iron enameled bathtubs, wash basins, sinks, etc., which have a cast iron surface coated with a glass layer. As a raw material for the glass layer of this type of cast iron enamel, a milky white frit containing a zircon component or an antimony component (zircon type or Niannamon yarn milky white frit) is generally used. In the above-mentioned applications, chemical resistance such as acidity and alkali resistance, hot water resistance, and thermal shock resistance are required, and in addition, uniform milky white color development from the viewpoint of appearance and φ is required. The above-mentioned zircon yarn or antimony yarn opalescent arift has poor thermal shock resistance and is also inferior in opalescence. If the glass layer is made thicker in order to obtain uniform opalescence, the thermal shock resistance will be even worse. In order to improve the drawbacks of such zircon-based or antimony-based milky white frits, a method is also proposed in which zircon-based or antimony-based milky white frits with different thermal expansion coefficients are prepared and these are used depending on the part of the product. However, it goes without saying that such a method only unnecessarily complicates the manufacturing process. The zircon-based opalescent frit also has the disadvantage of poor acid resistance and cannot be used with acidic cleaning agents.

To improve the drawbacks of the above-mentioned zircon-based or antimony thread milky-white frit, a milky-white frit containing titanium component iO3 (titanium-based milky-white frit) has been developed (
Special Publication No. 187-8T'187).

Is titanium-based milky white frit superior to zircon-based, antimony thread, or white frit? A product with L whiteness and a uniform opalescent appearance can be obtained, but it also has mulberry resistance, hot water resistance, and! ? I! It cannot be said that the impact resistance is still satisfactory. Therefore, in this field of industry, there is a need for milky white IJ that has excellent chemical resistance, hot water resistance, thermal shock resistance, and milky whiteness, that is, has excellent overall performance. The development of the HTML was requested.

The present invention aims to meet the above needs.

For the above purpose, the present inventors have focused particularly on titanium-based milky white frits, and have completed the present invention through extensive research to improve the above-mentioned drawbacks of the frits. However, the milky white ant of the present invention includes 100 parts by weight of the first component group and the second component group.
The first component group consists of SiO□, ZrO2゜Ti0BO and RO,
SiO and 2'2g" 2
The total amount of 2ZrO and TiO is 50
．． 0 to 85.0% by weight, ZrOu 2.
OA-15,0! M%, 12 for Tie2. O~25,
Contains in the range of 0% by weight 'F1. B2O3 is 5.0-80
．． 0% by weight, and RO is contained in a range of 5.0 to 800% by weight, and the second component group includes F, elementary components, PO,
It consists of AI O, ZnO, MgO, and BaO, and the fluorine component of the second component group is 0.5 to 10, oiit parts with respect to 100 parts by weight of the first component group.

PO is 0.5 to 10.0 parts by weight, AJ208 is 0.1
~5.0 parts by weight, ZnO#10.5~Jmi parts, Ba
O is 0.5-4! Parts by weight, MgO is in the range of 0.1 to 1.5 parts by weight.
It is characterized by having undergone a heat treatment for 0 minutes.

The present invention will be explained in detail below.

As mentioned above, the first component is S' 02 and 2.0 ~]
5.0% by weight of ZrO and 12.0-25. O] [5'
The total amount of 6 and TiO2 is 50.0 to 85. Oi amount%
, B2O3 in an amount of 5.0 to 30.0% by weight, and R20 in an amount of 5.0 to 80.0% by weight. ZrO2
is surface 1 hydrothermal of the glass layer.

It is involved in the acidity, and therefore, if ZrO□ is less than 2+W% (hereinafter simply referred to as %), the hot water resistance of the resulting product will be significantly inferior, or if it exceeds 15.03% by weight. and deteriorate acid resistance. TiO2 is involved in the opalescence, impact resistance, and hot water resistance of the glass layer; if it is less than 12%, the opalescence and impact resistance become poor, but if it exceeds 25%, the hot water resistance is deteriorated. Furthermore, SiOTiO and ZrO
If the total amount of 2 is less than 50%, the acid resistance and hot water resistance of 2' will be significantly reduced, and if it exceeds 85%, 2' will become significantly poorly soluble and will lose its practical use.

It is involved in the easy solubility of B2O3 hafrit and therefore BO
If it is less than 5%, it will become soluble and the milkiness will also decrease, but if it exceeds 30%, the hot water resistance and alkali resistance will be significantly deteriorated.As mentioned above, the second component group is a fluorine component. and 0.5 to 10.0 parts by weight of the fluorine component per 100 parts of the first component, P2
0. is preferably contained in an amount of 0.5 to 10.0 parts by weight. After all, the fluorine component and P2O5 have thermal shock resistance.
These components are involved in whiteness, and if these components are less than 0.5 parts by weight (hereinafter simply referred to as parts), it is difficult to obtain good whiteness.
If it exceeds 0.0 parts, the bad influence W will no longer be exerted.

The second component group further includes AI, 20 a a Z nO, k
Includes IgO and BaO. AJO is preferred for supplementing the properties of the first component and improves the opalescence of TiO. Al2O8 is 0.1 to 100 parts of the first component group
Preferably 5 parts. If A71208 is less than 0.1 part, it is not sufficient to improve the opalescence of TiO2 (,
If it exceeds 5.0 parts, the alit will be dissolved abundantly and the smoothness will deteriorate. 0.5 for 100 parts VC of Zn0H first component group
-4.0 parts is desirable. If anything, Zn
O is particularly effective in improving thermal properties within the range of 0.
If the amount is less than 5 parts, the effect will not be sufficient, and if it is more than 4 parts, the acid resistance will be poor. BaO is the heat of the milky white frit of the present invention.
The degree of expansion is adjusted, and the amount added is preferably 0.5 to 4.0 parts per 100 parts of the first component group.

If BaO is less than 0.5 parts, it will not give a sufficient n&tension effect to the milky white frit of the present invention, and if it is more than 4.0 parts, the fired skin will become wrinkled after firing. MgO is the first subclass 100
It is desirable that the amount is 0.1 to 1.5 parts. M
If gO is less than 0.1 part, the color stability will be poor and the color will vary.
If it exceeds 1.5 parts, the gloss becomes dull.

In addition to the above composition, the milky white alit of the present invention may contain 5b208. V2052Mo08. One or more modifiers such as SnO3, preferably 10% or less, Co
o, NiO, MnO, CuO, Fe2O, Cr2O3
Preferably 10% of one or more pickling agents such as
The following or other subcomponents can be added without losing the characteristics of the opalescent slit of the present invention.

The coefficient of thermal expansion of the opalescent frit of the present invention is adjusted to be slightly smaller than the coefficient of thermal expansion of the casting base by adjusting the amount of BaO added in the second component. This is because if the thermal expansion coefficient of the opalescent frit is too smaller than that of the casting base, teffing is likely to occur after firing, whereas if it is too large, cracks may occur. For example, if a material with a thermal expansion coefficient of about 850 to 870
It is desirable to adjust the thermal expansion coefficient to approximately 0×IO.

In the present invention, the milky white fleet with the above composition is 520 to 6
Heat treatment is performed at 30° C. for 5 to 20 minutes.

Opalescence imparting particles such as ZrO and TiO□, which relatively dissolve in the glassy composition when the glassy composition is made into a fleet from its melting point, are called soluble particles. When applied by the method, the degree and speed of nucleation and crystallization of soluble particles vary depending on the location on the base surface due to fluctuations in thermal properties such as temperature, heat capacity, cooling rate, etc. of the base surface. Irregular stains, uneven spots, etc. can cause the rod to have an undesirable appearance. Therefore, as mentioned above, by heat treatment at a temperature higher than the nucleation temperature of the soluble particles or lower than the melting point of the frit, at least a part of the soluble particles are precipitated in the form of crystals, and the above irregular stains can be caused. This prevents the occurrence of unevenness and provides a desirable milky white appearance. Furthermore, such heat treatment also improves the flow characteristics of the frit,
The smoothness and gloss of the enamel surface cannot be improved.

The milky white alit of the present invention thus obtained contains -SiO2# ZrO2# T'02# as an essential component.
B 208 Since it contains mRO, a fluorine component, and p2o in a predetermined ratio as mentioned above, it has chemical resistance;
Hot water resistant.

This makes it possible to provide a product that satisfies all aspects of brightness, heat-stimulating properties, and opalescence properties.

Example Sample Na of Table 1 within the composition range of 7 lifts of the present invention
Various raw materials were blended so as to correspond to the composition of 1-Nl 10, mixed and melted at 1200 to 1800°C, and then rapidly cooled to obtain an alit. In the same manner, alits of comparative examples shown in the same table were obtained.

These alits are subjected to heat treatment at 520 to 630°C for 5 to 20 minutes. This heat-treated frit was dry ground on a 200 mesh sieve (sieve mesh opening 74μ) to the extent that 10 to 20% remained.
The above frit was sprinkled on a cast iron plate fired at 50°C while it was still red hot, and fired in a furnace at 950°C for 50 to 90 seconds.

The following performance tests were conducted on each of the test pieces obtained, and the performances were compared. That is, as performance tests, the whiteness resistance test, old acid test, (1) alkaline test, and hot water resistance test were conducted.

1. Whiteness [W (Lad)] Whiteness was measured using Suga Test Instruments vA dynamic CDE-8CH-I.
Using a mold, measure the diffuse reflectance, *, b value,
Substitute into Hunter's whiteness formula to obtain whiteness (W (Lab))
get. Measured values are shown as the average value of 5 samples.

2. Dramatic heat shock 14 test After keeping the test piece in a 150°C heater for 20 minutes, take it out and immediately put it into water at room IML (18-20°C). After identifying the cracks using the red ink permeability method, repeat this operation.

The above heating and cooling cycle was performed 5 times, and those with no cracks were evaluated as good, those with cracks only in the #A area were evaluated as fair, and those with cracks on the entire surface were evaluated as poor.08, Acid resistance test international standard l5O-2788 6 using test equipment similar to
Add 400 ml of % citric acid aqueous solution.

The weight loss of the floating layer after being kept in a boiling state for 24 hours was determined per unit test surface area, and the average value of 3 samples was expressed in g/g/day.

4. Using a test device conforming to the n1it hydrothermal test international standard l5O-2788,
Ion exchange pure water 400m7! After holding it for 48 hours in a j1ti tower, the weight loss of the #1 moisture layer was determined per unit test surface area, and the average value of the 8 samples was calculated as υ, g/m/
Shown in days.

5.1lfJ alkalinity test 6 using a test equipment according to international standard l5O-2784
% Sodium birophosphate aqueous solution 320ml, 8
After heating in constant temperature water at 0℃±l''C and keeping it for 24 hours, the weight loss of the waxy layer was determined based on the unit test surface area.
The average value of the samples is taken and expressed in g/go/day.

6. Color stability Suga is baked at 900℃ and 940℃ for 50 seconds↓ △ value　　Within 4　　0 4～6　　　△ 6 or more × The results of the above performance test are shown in Table 1.

According to Table 1, comparative sample A containing 2% or less of ZrO3,
It is clear that G and H have inferior hot water resistance compared to samples Nn1-10, and it is clear that sample B, which contains 15% or more of ZrO2, has inferior acid resistance compared to sample M ~ Arashi 1O. . In addition, comparison sample 11d containing 1296 or less of T' 02 has higher opalescence and PA resistance compared to 1 to N [110].
Comparative sample G, which has poor impact properties and contains 25% or more, is a sample with a lower impact resistance.
-Poor hot water resistance compared to Arashi 10 9 and 5% B2O3
Comparative sample C containing the following is poorly soluble and inferior in opalescence compared to samples NQ1 to 10, and comparative sample C containing 30% or more is significantly inferior in hot water resistance and alkali resistance compared to samples N1 to ilO. .

In addition, the comparative sample containing no BaO has an abnormally lower coefficient of thermal expansion than sample N15, and has a lower thermal attack resistance. Ba
Comparative sample F containing 4% or more of O has a fired skin with wrinkles and a poor surface condition compared to sample 0. The comparative sample that does not contain ZnO has poor hot water resistance compared to sample 1, and the comparative sample F that contains 4% or more of ZnO is sample IV! Compared to 1x to 10, the acidity of 1 town becomes more relaxed. Comparative sample DGHIJKfi that does not contain MgO.

The color stability is better than sample %1~10IC, MgO is 1
．． Comparative sample E containing 5 or more loses its luster.

Thus, sample descriptions 1 to NlXl0 according to the present invention have acid resistance, alkali resistance, hot water resistance, heat resistance @ impact resistance, as shown in Table 1.
It shows excellent performance in all aspects of opalescence and completely eliminates the drawbacks of conventional opalescence frits of this type. Therefore, the cast enamel bathtub for the frit of the present invention,
#Enameled sinks can be used under harsh usage conditions, such as strong acidic detergents and strong alkaline bath additives, which have traditionally been difficult to apply. It is sufficient to use approximately half the amount of zircon-based or antimony-based frit, and thus the amount of glaze used can be greatly reduced, and furthermore, the reduction in the amount used can further improve thermal shock resistance. bring. The frit of the present invention is a part of the product.

For example, there is no need for complicated methods such as using different types of glaze for the upper edge and inner surface of the sink.
Only one type of frit can be applied to any part of the product, greatly streamlining the manufacturing process.

Patent applicant: Nippon Flit Co., Ltd. Nippon Insulator Co., Ltd.

Claims (2)

[Claims] (1) 100 parts by weight of the first component group and 6.0 to 3 parts by weight of the second component group
The first component group is SiO_2, ZrO_2, TiO_2, B_2O_3,
and R_2O, SiO_2, ZrO_2 and T
The total amount with iO_2 is 5.0 to 85.0% by weight,
and ZrO_2 is 2.0 to 15.0% by weight, TiO_2
is contained in the range of 12.0 to 25.0% by weight, and B_2O
_3 is 5.0-30.0% by weight and R_2O is 5.0
The second component group includes fluorine components P_2O_5, Al_2O_3, ZnO, M
gO and BaO, the fluorine component of the second component group is 0.5 to 10 parts by weight with respect to 100 parts by weight of the first component group, P_2O_5 is 0.5 to 10.0 parts by weight, Al_2O
_3 is 0.1 to 5 parts by weight, ZnO is 0.5 to 4 parts by weight B
aO is 0.5 to 4 parts by weight MgO is in the range of 0.1 to 1.5 parts by weight.
A milky white frit for dry casting, which is characterized by having been heat-treated for 30 minutes. (2) The opalescent frit for dry casting according to "Claim 1", which contains subcomponents such as an opacifying agent, a surface tension regulator, and other improving agents, and a coloring agent.