DE1909187A1 - Opalescent glass - Google Patents

Description

The invention relates to glass compositions and methods for producing opal and opalescent glass objects these glass compositions.

- With the term "opal glass" as it is used here; will denotes a type of Glaucoma that contains a licnt-dispersing medium, which essentially diffuses light and thus makes the glass transparent or opaque. The term "opalescent glass" refers to those types of opal glass that have a scattering effect Contains medium that makes the glass transparent, Different types of opal glass are known: Opalizing agents such as ile used so far are, for example, titanium and tin compounds, Fluorides, Sulphates, Chlorides, Plcsphates and various other salts. Fluoride opal glass was known in particular

For lighting purposes it is used / ends as it is in a wide area Opal density (degree of friction) aufweisb. Other known forms of

909837 / 13H BAD ORiQINAL

Opal glass is fire opal and alabaster glass i: .um ^L HeVs ^: te "" llen von "lighting glass and other glass objects.

iJas erfiridungsgemäße opal glass can be used for the above-mentioned Z v / corner and other purposes also be used _3, specifically f'iir scientific, industrial and. commercial purposes, in the form of containers for therapeutic and cosmetic creams, for lighted globe, flasfliter and the like.

En Recently, there is a growing need 'in cheap, high quality j heat resistant and ehemisr "; stable opal glass container era, .lie with customary fast ilasnerstellungöverfahren in large quantities can be produced, the known opal (Ilasarten not meet these requirements because the manufacture. of conventional opal glass it is often necessary to repair or replace the furnace which was used in the manufacture of / ended melting furnace due to the corrosion mechanisms of opalizing agents (eg, fluorides and phosphates) at frequent intervals. This is expensive and makes long-term continuous operation is impossible, and the raw material cost of such opal glass types is generally high in comparison

DOS
'.u the cost of the raw materials / usual soda-lime-silica glass. ^Another: Tachteil the known methods for creating of opal glass is that the Brennstoffverrauch of gas-fired furnaces in the smelting and refining is very loch. The fuel costs are particularly bad because the molten glass itself is opal lab and radiation energy from the molten glass is reflected rather than absorbed

■ fird.

909837 / 13U

Another disadvantage of the known opal glass is that the turbidity is often difficult to control, and the Inconsistency of the cloudiness of a finished glass specimen is often a problem. This non-uniformity is due to poor mixing of the opalescent agent in the crucible, what a locally different development of the opalization properties has the consequence.

The invention avoids these disadvantages. A thermally opalescent glass is characterized according to the invention by the following composition:

Component weight percentage

SiO ₂ 55-76

Al ₃ O ₃ 1.5-12

B ₂ O ₇ 0-13

CaO 5-2o

MgO 0-15

1-11

0-5

<2

Io -

Weight percent B ₀ O-.

< - j ο

Weight percent Na ^ O

(SiO ₂ + Al ₂ O + B ₂ 0 ₃ + Ca0 + Hg0 + Na ₂ 0)

Well ₂ 0 the conditions ₂ o + k ₂ o) K ₂ O (CaO + MgO) ^Ijl 2 0 (N / A with

909837 / 13U

In the following, examples are now in connection with the drawings the invention explained in more detail. Show it:

Fig. 1 is a diagram in which the inflexion and transmission properties of an opal glass as a function of the Wavelength are plotted,

Fig. 2 is a ternary diagram in which the suitable for the invention Glass composition range is shown,

Fig. 3 is a diagram in which the reflection properties be -, < Time between opal glass types depending on the wavelength are applied.

According to the invention, certain types of glass are made from alkaline earth aluminum ili-at groups are melted in the usual manner and a specific one Subjected to heat treatment through which a desired Opali sit? tion achieved by means of an in situ glass: glass phase separation will. The turbidity can be adjusted on the basis of this analysis or the degree of permeability through one with respect to the composition affect properly chosen heat treatment.

The glaze used today usually consists of six components. These components and their essential importance for the glass are briefly described.

The predominant glass-forming oxide J r; t of course silicon; i <x.yd (SiOo) > whose importance for glass is known.

909837 / 13U

BATH ORIGINAL

Glass also contains aluminum oxide (Al ₀ O-,) _} which serves two purposes: Λ) The presence of aluminum oxide increases the resistance that the glass offers to devitrification during opalization heat treatment.

f3) The presence of Aluininiumox / d makes the speed of opalization, since the rate of opalization increases with increasing amounts of AIpC).

These two effects are dependent on the glass viscosity and hence are related to the Al ₀ O moiety together, since the Al ₂ O moiety essentially determined the viscosity of the known types of glass.

Furthermore, the alkaline earth oxides CaO and MgO are usually present, the chemical stability of the finely divided opalization phase looking to enlarge. These oxides also affect the glass viscosity.

Ferm; r 1st Boüroxyd BpO? present, which is the primary opalization agent, since the opalization increases with the greater "/ grounding portion B ₀ O-.

Soda (Iia _p 0) serves, apart from as a flux, as a stabilizing agent, which reduces the tendency to opalize as the proportion of soda increases. The ratio of Na ₀ O and B ₀ O., then, is important in determining the time and duration of the opalization heat treatment. It was found that opalescent glass v, prepared without Napo or BpO / can ground, but the opalescence of these types of glass is far less easy than in glasses which contain these two ingredients. Types of glass that

9O90T7V1.3U BATH ORIGINAL

909187

Ma ₀ O and B ₀ O-; therefore preferred

- • / eLte.ro alkali oxides such as haliunioxyd {■ ',,'>)) and lithium oxide can

also call in, difi in the following table The EnfcglassuiitS at high Ι to rv .: eL _f ; t 6 ο - in the are present tf.iin. Preferably, however, none Ethium oxide 4 - present because this oxide fczun ,; of these components Temperatures 1 - r_ _Be_re i_c; promotes. given in the following table: ο - To The shares and öusammense Oxyjie Vierden 4 - 3 3 - 9 Al ₂ O ₃ ^; le ^T 'iichtspi'ozorite
al_l ^ emeiiier_ "area bo / orzugba 0 16 B ₂ O ₃ 55 - 7ü 0 12th CaO 1.5 - 12 7th Αφ 0-13 14 - Ha ₀ O 5 - 2o K ₀ O 0 - \ 5 O.2 - 1 - 1 L > 93 21 with the conditions: O - -j (CaOf ₁ IGO) * - 2 (Ha _o 0 + K _o 0) Percent by weight; jpO
Weight percent Ha ₀ Io - "5o (SiOg + AlpO., FB ₉ O-, FCaO
M ^ OFrIa ₂ OtKpO) ^ 11 0 «- 5 f
> 95 -Ο

909837/1314

BAD ORIGINAt

usually "earth be colored Oxyde- wi'- at ar i el sweiae the

V (ii'v; oxides of cobalt, copper. Chromium, Hiekcl "and i-fon ^ an ^ inn opales and ends to produce opal glass of various colors and shades, Films, colors and shadows can thus be controlled be. that the oxygen level of the melt, the side and the temperature of the heat treatment can be controlled. These Coloring Oxy-Ir generally do not make more than about 2 " the total weight.

In carrying out the hrfindunc: ^v #ird a Erda silicate ßlas In the above-defined Z amme us η r> ^ et mißsbereich execute; ev.'ühlt. The small proportions of P ₀ O ^ and Na ₀ O are necessary to produce the desired slide separation and to control zxx. Lk \ / urde fo "t -r / .steps ₃ that the presence of these two Dc · Jta'ndteilc Künoclionsviert i" t _{s around the overpan = des atiian ^ s see-} through! Glasc; ii. Dr o opal or oT? Al «? szif ι r ι ^; en ϊ-.ui i and n.ö (-] i ciist ί ui Meuert zu -! "

The glass with clr? J »f; evi [-hlten Zusainmenset Kunf; vrird fenehnc l ^ en and according to the ühlin .-. n process, shaped into objects. Here you can

-in ^ sniatei ialien vr rr / ondet v, 'earth: i _s vorau ::.'". eset :: t tj; e \ Jünschte Zusain-.sr.nsetzun ^ formed v.'erden Can" it: t sinh in the wc-eu quite a few on v / irtschafl .liclir Jji.TtveriJtijndlioIi i53te the rschnnlzßnc glass should be borrowed, hevcr the glass from it; ef; enf t ands

that from them · iJiese /-u.i.ia; I. ÜlierJ (?, Un css. So homogeneous' Ie Ce forms ".,

V / enn

τη.Μ; nd r; efrrmt is. '/ ird he ^ in a certain uut «; ri: o'cen, and sviar during a time which from - 7 -

909837/1314 BAD.QBföJNAL-.e

raw to produce the desired phase separation.

In some compositions according to the invention this occurs Phase separation so quickly. That the glass is under the influence of the thermal conditions that prevail during the molding process., becomes opal or opalescent.

jci other compositions of the invention it is necessary for the glass Gage state after forming a specific heat treatment to undergo _s by a certain Opalisierungsgrad to achieve. The invention provides, on the one hand, a large range of thermally opalescent glass and, on the other hand, defines the relationship between these compositions and the heat treatment required for the treatment

The relation to time and temperature for the heat treatment depends primarily on the composition of the material. It should be understood that higher temperatures require a shorter period of time to cause the desired phase separation, but that the glass is more easily deformed and devitrified at these high temperatures. Temperatures are satisfactory from 600 ⁰ C to about 980 ⁰ C during a period of 15 minutes to about 6 J ¹ or more hours for the purposes of the invention. In general, for economic reasons, temperatures between 65 ° C and 85 ° G for a period of 3c minutes to about u hours are preferred Favored formation of opal glass

909837/1314

BAD, ORlGINAt.

The degree of opalization can thus be determined by the time-temperature relationship; control effectively.

As mentioned earlier, the presence of Na ₂ O is in the glass
important because it helps stabilize the opal glass. The tendency of the glass to undergo phase separation decreases with an increasing proportion of Na ₃ O within the ranges mentioned.

BpO is important insofar as the proportion of
BpO, the tendency of the glass to undergo phase separation, increases. By balancing the BpO and Na-O antells with respect to the amount of other oxides present, the properties of the resulting opalescent glass can be influenced.

The exact mechanism by which the phase separation which causes the opalization takes place is not yet known. It is believed, however, that a physico-chemical process known as "spinodal decomposition" plays an essential role in the opalization process
Zei'iie't-zuf, determining factors oind not yet; fully understood, but it is known that the composition and time and temperature of the heat treatment are Ίίο essential factors.

The spinodal decomposition urine Latin "bo.written v; Erl? N as the separation of a solution of two or more bentand parts in at least; zv / ei _; /.; separates phases, dia lie within the unstable apinodal i-rich clt'ij PhuLjriiidlagrainms lie ^ . Phasentrennuru on _dienes;; is al) "fj
daL ", as this term is the moose, who is by a

909837/1 3U

Free energy thermodynamic property curve included is described mathematically as a puncture of the composition in the area in which the phase separation takes place.

When the heat treatment has been performed correctly 1st _3, the glass consists essentially in two "separate but continuous glass phases is disconnected. (Usually, no crystalline phase present.) Due to this phase separation, the glass is opalescent, this glass phases t'.ine 1st reicli to Aluminiumoxydj Alkaline earth oxides, soda, and bohrroxides. This gas phase is relatively stable and fairly resistant to acids and alkalis. The other glass phase is rich in silicon oxide and also very stable. It can be observed that the division ratio of the phases corresponds to the ratio of their respective phases Components in the original glass.

As mentioned earlier, the higher temp era doors require one shorter period of time to bring about the desired phase breakdown, Ahoi · hu i'rl.is gets easier at these higher temperatures deformed or ent / Iu - ') t. Generally speaking, the glass is rait that. Above 'enarmten' usaminensetzunp'sbereicri with the necessary i / i rmebeiianaium; fairly resistant to de-glazing. ■ ■. -.

t,. ·. no.-d-.in now some;.? Aujf ührun ^ sboist, io Le des erf indun-; öüemäße; i ■ iia.ie.-5 bejcarieuiui, The o-.tischan properties of the execution unrsuei-.5 |) iele uevueu in connection iait the devices, ir.it : onen the optical Sip; -nactirifte i; f; met;:; en atrien, bescru "L; aen,

- Io -

9Ü00 37 / 13U

BATHROOM 0RIGir4AL

The difficulty criteria. the optical properties of HaterllSen ₃ when measuring and comparing which have the heating to disperse an incident light beam (for example opalescent

appear,
and opalescent - ?? = glass), -AvX \ known. The basic problem stirs ⁴ therefore j daft a Tr j 3 of the Μ "r ah I auxiliary energy., Which enters the sample, within Cer Proi-e dispersed ^T v3rd and that of ordinary Spelitrop> oi c-s'itern not al π re fell tf nrte ₅ or absorbed durchseia: ri-nn radiation is detected, _"1 Df S test procedure that was used in the sbeispielen Ausführun ^ tries the B-en scattering effect vv: l-.onyensieren.

De_isj3le 1 _1

3,618.53 f-.

Potash?

175, ^ 3 G 116, il3 r

85, IB G

The iiupran'-. Sinateria 11 en

Sa; κ!

High DclomJ tlTlk

Mips, high l-al.-Hiiallin

Alumina oxide Boj'ax

Uat ri um carb onat Calcium carbonate

are Keschmolsen in a crucible made of platinum at a glass temperature of 1,593 ° C in an electric furnace with mechanical stirring. The rug SchmelZKeit offered about 2 J ¹ hour, slchorruntelleii to homogeneity. From ύνν. -; oκ ^ inaolseilen Glaπ were after an ih. borrowed.-n 3: the procedure on mehi'ori Glasbeeher hurries down. The finished lilac cups were transparent and had the appearance of 5 ewöhial3 e: ii3ii Sodafaali'-Ulasbochern raid d3o had the following composition and properties:

- 11 -

909837/1314

BATH ORIGINAL

component

SIO 2 Al ₂ ° 3 CaO MgO Well ₂ 0 K ₂ O B ₂ O 3

Pe ₃ O ₃ (impurity)

Percentage by weight 71,558 6.5% -9.6% 6.2% 2.8 $ 1.2Ji 2Λ% ο.ί%

Temperature for viscosity Ιο- ⁷ 1,351 C Ii τι ι ίο ⁷ 926 ⁰ C

Liquidus temperature

Viscosity at liquid temperature

temperature

Thermal expansion coefficient / ° C
χ Io7 (o-3oo ° C)

1,227 ° C

Io

3.7

The glass beakers are then kept in an electric oven at a temperature of 800 ° C. for 2 * 1 hours. At the end of this For a long time, the glass beakers were uniformly opaque-opal. The other properties of the glass (density, chemical resistance, Expansion coefficient) were not significantly changed by this heat treatment.

Example 2

Starting materials were made according to the procedure of the execution game 1 melted into a homogeneous glass, which has the following composition and properties:

- 12 -

909837 / 13U

BATH ORIGINAL

η 1909187 Ingredient percentages by weight 7o.6 $ j and each of these panels Plates were not exposed to any heat SiO ₂ 6.8% was in an electrical laboratory furnace of a certain Comparison object. Al ₂ O ₃ 9.4JS Subjected to heat treatment. One of the CaO 6.1 * treatment and served as a flgO 3-3 * Plate. J. visible light scattering Na ₂ O 1.4 * Heat treatment: none K ₂ O 2.2 $
0 .06% Appearance: clear and transparent without B ₂ O ₃
Pe ₃ O ₃ (impurity) 124o ° C Plate 2 Appearance: very light blue against a black background; Liquidus 56. Heat treatment: 2 hours at 800 ° C Thermal expansion
coefficient
/ ⁰ C χ lo ⁷ (0-3oo ° C) The molten glass was divided into several small rectangular plates th (25x19x3 mm) cast. The panels were after casting clear and transparent. Three of these plates were selected

0983% 7it53-U BATH

J -Λ-h-

low turbidity,

Plate. YY

Heat treatment: 2 hours at 830 ^° C.

Appearance: dark blue against a black background ; distinct clouding.

Plate Jl

Heat treatment: 2 hours at 900 ° C

Appearance: completely opaque-opal

To the optical properties of the plate ^l \ vielter characterize the Refle-xion and permeability with respect to radiation energy was determined with spektrophobomebrisclien ilitteln after the samples ground and polished. '; Aren, remove surface imperfections to. The spectral transmittance data were determined by means of a Jeckman-Spe ¹ trophotometer DK-2A, which is equipped with an integrating hollow ball in order to be able to better absorb the scattered radiation The amount of energy (measured over the wavelength range of interest) was then recorded as a percentage of the amount of energy incident on the sample By this method, almost all of the energy incident on the sample is captured.

- 14 -

909837 / 13U

The Rei'le-xLons and permeability curves for the plate 4 in Dependencies on the wavelength are shown in FIG. 1. These curves are characteristic of highly opaque-opal types of glass.

Embodiment J5

In order to further show the properties of the opal glass according to the invention. Several samples were produced according to the glass composition of embodiment 2 for a density determination. the The density of the clear, translucent glass was measured by conventional methods and found to be 2.4691 g / cm. A similar sample The same (J. - ^ composition was used for 21 hours at 93o ° C heat treated. At the end of this heat treatment, the sample was uniformly opal. The density was 2.5591 g / cm, which is an increase of approximately 3.6 #.

From Guide e gsbeispiel JL_

Starting materials were prepared according to the method of the working example 1 melted to a homogeneous glass of the following composition:

Weight percent 62.O5S

Bert nd part SU » Approx MgC) Well ₂ 0 B ₂ O 3

7.5 * 5.O5S

Of the. Molten glass rods were drawn, which one subsequently let cool in the ambient air. The pole was

- 15 -

909837 / 13U
BAp ORiGlNAL "

divided into ptfo sticks that looked clear and see-through.

Several of the test bars were heat treated at 800 ° C. for 64 hours. The resulting glass was uniformly opal. The X-ray diffraction pattern of this opal glass showed ₃ that noticeable amounts of the crystal type diopside (GaO.MgO.2SiO ₂ ) were present in the surface. This means that the invention. Glass is devitrified even with extensive heat treatment (which is true of most types of glass), but the presence of this type of crystal does not damage the opacity.

Embodiment 5 ^,

Starting materials were prepared following the procedure of the embodiment 1 melted to a glass with the following composition and properties:

Constituent part l weight percent e

68.85?

11.33ί 7.3 *

SiO 2 Al ₂ ° 3 CaO MgO Well ₂ 0 K ₂ O B ₂ O 3

Temperature at viscosity lo ⁵ 1293 ° C π 11 it _lo 7 877 ⁰ C

Liquidus temperature ⁰

Viscosity at liquidus temperature

-16 -

909837/1314
BAD ORfGINAL *

The weight of a crucible filling; was about 4.5 kg, and the melting was carried out in a refractory container at 1593 ° C in a gas-fired furnace for 24 hours under mechanical Stirring carried out. Test rods were sucked from the melt. The test bars were clear and see-through. To the influence of the To determine the opalization on the glass stability, fatigue strength tests were carried out with the clear glass and the opalized glass executed. The standard US Pharmacopeia XVII procedure was used used. This procedure is called:

United States Pharmacopeia XVII container glass chemical resistance to water Glass powder test

The method is also C-225-59T by ASTiI (Method P.W. Resistance of Powdered Sample to Attack by Distilled Water).

Generally speaking, the method consists in making an extract of a glass powder sample with a given volume of mass at an elevated temperature for a certain period of time. At the end of this period, the water is titrated with n / 50 HpSOj to the neutral point in order to neutralize the powdered glass extract. The results of the experiment are given in millimeters of the required n / 50 HpSO ^. The lower the number of ml of n / 5o HpSO ₁ . the better the chemical resistance.

- 17 -

909837/1 aU BAD ORIGINAL

The following test results were obtained: The small and transparent test rods required 1.8 ml. n / 50 L ₂ SOh and the opaque-opal test rods (after heating for 10 hours at 800 ° C) 2.5 ml. n / 50 H ₂ SO ₁ . ^ a den Vi:. '. neutralize aerauczuc. Oleo i: eu; t that the chemi. the durability negen over water through the opalescent heat treatment: ;; not weaent-; loaned is reduced.

Executionmi ^ sbeigjpJLe_l J)

Using the method of embodiment 1, compositions CA _5, 6L and 6C (see below) were melted from suitable starting materials, and clear, transparent test rods were drawn from the melt. Attempts were made to determine the minimum time-temperature relationship at which opalization would occur. The times and temperatures listed below are the minimum temperatures at the given times at which the glass composition becomes slightly cloudy or "milky".

Ingredient per cent by weight

6a 6b 6c

SiO ₂ 69.72 69.855 64.85?

Al ₂ O ₅ 6.3% 6.25? 6.7%

CaO IO.652 10.6g 11.2J6

MgO 7.3% JH% 7Λ%

Ha ₅ O 3.0% 5.0% 3 7? 4

B ₃ O ₃ 2.9 £ 1.0 #

-18-

9 0 9837/1 3U
BATH ORIGINAL

component 10 ³ Weight percent 6A 6b ⁰ C 6C 10 ⁷ 1229 ° C 1313 1251 ⁰ C Temperature at viscosity 877 ° C ⁰ C "" Vi sk os it V. t 1331 ° C 1248 1215 ° C Liquidus temperature ₁₀ 3.0 10 ³ ₁₀ 3.2 Viscosity for liquid
temperature

Line

lh 64h

Temperature 6a 6b

6C

800 ° C no opalization 710 ⁰ C

725 ° C

72O ° C

675 ° C

Example 7

The following values illustrate the relationship more precisely between the treatment and the composition of the invention Glass type rn.

Glass with the composition was made according to the procedure of embodiment 1 from suitable starting materials melted, and rods 12.7 cm long and about 0.6 cm in diameter were drawn from the melt. The appearance of these rods was registered.

-19-

90 98 377 13U

The bars were then heat treated _{3 to} determine the following temperatures:

TuI: Lowest temperature at which after one hour of heat treatment a slight opalescence (weak haze) is visible;

ToI: Lowest temperature at which after one hour of heat treatment a dense white opal glass is created

Tu64: Lowest temperature at which after a heat treatment a faint opalescence visible from 64 hours Istj

To64! Lowest temperature at which after treatment of 64 hours a dense white opal glass is created.

These temperatures were determined by placing the rods in a gradient oven with a stabilized temperature profile for the specified period of time. Dft the *., Ι- _s öradlentehofen a well-known uniform 5PempäBi »a! 5üf |; i? A (| ienter

^! vbn about 35Ö 6 over the length of the rod up> ί

exact temperature for each radio dfes, stick is known. The _s

:. . '. · ^; - ', - ■'. ■ .. = ■ ν-. ■ '.', - ■ ..-: -. ■■■ -.- ^ - ■ '■■: "f _S [-" ■■ · = ■ - ■ - ^j -v -; * ' ■ M. SSUE sihd t listed in Table _4p:; : V

! .it-; · ■ ■

-20-

909837/1314 ÖAO ORIQfNAL

TABLE I.

Glass composition in percent by weight

AI2O3 " Na ₂ O SiQ ₂ CaO ' MgO

B ₂ O ₃

Appearance _n Tu64 ToI Τοβή the bars Tul (° C) ^j ( ⁰ C) ( ⁰ C) ( ⁰ C)

after
1 h

after after 64 h l h

after, 64 h

7-1 2 3 73.0 12.9 9.1 0 opal —__ * 7-2 2 5 73.0 11.7 8.3 0 clear 310 725 * 7-3 η η 73.0 10.6 7.4 2 clear 760 675 * * 7-4 Il η 73.0 1.9.4 6.6 4th opalescent - - * I ⁷⁵ ° 7-5 U H 69.0 10.6 7.4 6th opalescent 825 730 7-6 η η 65.0 11.7 8.3 8th opalescent . «- 800 740 7-7 M. H 69.0 8.2 5.8 10 opalescent 780

73 .0 9 .4 6th .6 2 clear * * * * 73 .0 7th .0 5 .0 6th clear * 690 - * • * 69 .0 7th .0 5 .0 10 clear 750 675 * *

69.0

15.3 10.7

opal

7-12 ■ ι 3. 69.0 14.1 9.9 0 clear 720 690 * . 780 7-13 Il U 69.0 12.9 9.1 2 opalescent 775 7-14 Il Il 69.0 11.7 8.3 4th opalescent 7-15 Il η 61.0 15.3 10.7 6th clear * 715 * *

CO O COCO

Glass composition in Na ₂ O 5 SiO ₂ TABEL MgO B ₂ O ₃ I. TuS *!
( ⁰ O ( pole S! ro
IU Ex. Al ₂ O ₃ - η Weight percent Appearance
• the bars
TuI (C) after after after I. · .--:. N 73.0. CaO 7.4 0 after 64 h 1 h 6 ^ h ^Γ _ -. : - 4th H 69.0 7.4 4th 1 h 720 * 800 7-16 Il 7th 62.0 10.6 9.1 7th clear * 710 * 760 7-17 W. η 65.0 10.6 5.8 12th clear ⁷⁸⁰ 700 810 750 7-18 Il 0 70.0 12.9 3.7 10 clear ₍ 750 _ »—_ 740 725 7-19 4th 1.5 65.0 8.2 4.1 14th opalescent: - 680 * 730 7-20 • I Il 75.5 5.3 7.4 0.5 clear * 670 * 690 CD
O 7-21 6th η 74.0 5.9 7.4 0.5 clear 725-775 ^! _ _ ... OO 7-22 6th M. 67.0 10.6 9.9 1.5 opal -— «.« - 7-23 H 3 70.0 10.6 7.4 4.S opalescent -— 900 8X0 7-24 H M.
Il 67.0 14.1 7 = 4 7.S opalescent -— ... --- - "--- 7-25 η η 72.5 10.6 7.4 o.s opal -— _ .. «. 7-26 6th 71.5
70.0 10.6 7.4 1.5
3 opal - " - 730 925 800 7-26a π
Il 68.5 10.6 7.4 4.5 clear 820 700
680 *
910 775
760 7-27
7-28 Il 10.6
10.6 clear 840
clear 825 "- 850 --- 7-29 10.6 opalescent

7 * 30 Häszüs TUiSELLE I CaO ' HgO B2O3 '... H 775 Tu6i |
( ⁰ O ToI
( ⁰ C) Rc6i |
( ⁰ C) I. - ί I.
ro 7-31 Al ₂ Os adjustment in percent by weight ■ after '. after after
f Il * 760 ¹ * ■ ? -32 SÄ2Cf SiO2 7.4 6th Appearance
of the bars TuI ( ⁰ C) -. ^: * 6h h ' 1 h 64 h 775 7-35 6th ; j-i0.6 ί 7.4 7.5 after ■ * 800 750
740 7-? " N 110.6 7.4 9 800
760 -. 720 7-35 m 13.8 11.2 6th opalescent 750 710 to
O 7-36 N '■ -!. {, "I'V,'. M * & ~ 14.1 9.9 12th opal 740 710 j 880 700 <0
co 7-37
7-38 β ■: 10. « 7 "4 0 opal 760 690 Ca »
- «a! 7-39 6th «. ss.o 10.S 7.4 1.5 clear 740 720 1 ♦ 740 CO
O 7-40 ■ M ■ 5 _:: ; "■. '71 .0 10 6 7 _β 4
7.4 3
4.5 opal 760 720 * 670 CD 7-41 M.
a ■ - ;: ■ ·; \ ^ * 5. ^ 10.6 7.4 6th clear —— 700
680 * OD 7-42 ■■ '■■■ ^ ^ & .0?
> · ■ * a ■ - «■; '"-10« 6 7.4 7.5 clear 670 825 7-43 .J. "'■,, ;>:« 5.0 10 »6 7.4 9 clear
clear 600 800 7-> 44 "■ it 10.6 7.4 10.5 clear 655 810 ·· "62Λ * 10.6 7.4 5 clear 640 800
I. - N S0.5 IQ.6 7.4 12th clear 700 * clear 790 clear opalescent

- 7-45 Glass composition in Na ₂ O SiO ₂ TABLE I. MgO B ₂ O ₃ Appearance
the bars TuI ( ⁰ C) K rc) ( ⁸ C) ro Ex. 7-46 ^A1 2 ° 3 5 71.0 Weight percent 5.0 6th i after after after after 7-47 6th M. 69.0 CaO 4.1 10 clear
I. 750 64 h
680 1 h
825 64 h
740 7-48 It 7th 73.0 7.0 3.3 6th clear 750 670 * 725 7-49 6th H 65.0 5.9 5.8 8th clear ' * 670 * 700 7-50 - M. 61.0 4.7 5.0 14th clear . * 675 * * 7-51 n 9 65.0 8.2 6.6 4th _clear 710 670 700 * 7-52 6th M. 65.0 7.0 5.8 6th clear * 660 * 700 —Λ
CO
O
CO 7-53 It 3 71.0 9.4 6.6 2 clear * 680 * 725 OO 7-54 8th N 65.0 8.2 7.4 6th clear 850 740 * 800 7-55 H It 71.0 9.4 3.3, 10 clear 800 725 875 740 7-56
7-57 It It 67.0 10.6 3.3 14th clear 785 790 * * V58 N 3
N 67.0
67.0 4.7 5.8
4.1 6th
10 clear 775 775 * * - 7-59 10
It η 55.0 4.7 7.4 14th clear
clear 830
* 690
750 T 775
* η 5 63.0 8.2
5.9 6.6 6th clear 760 710 790 730 10 10.6 clear * 730 * 770 9.4

CD CD CO OO

Ex. Glass composition TABLE I.
Appearance
in percent by weight of the bars TuI Tu64 ToI
- ( ⁸ C) To64
( ⁸ C) 1
ro
VJl
I. • Al ₃ O ₃ Na ₃ O SIO ₂ CaO MgO B ₂ O ₃ after
1 h after
64 h after
1 h after
64 h 7-60 Io 5 55.0 9.4 6.6 14 clear 74o 690 785 72o Notes: + means that opalization under the test conditions not a- kicked is. means ₃
became. not evaluated that the special test conditions 1909 ' • OO
• »4

A glass within the composition range according to the invention, the components of which have approximately the following percentages by weight, possesses commercially desirable shape properties such as viscosity -Temperature relationship, liquidus temperature and thermal Expandability, can be made from relatively inexpensive raw materials, has good chemical resistance and can be modified according to the usual procedures in a Compensation process to be opalized:

SiO ₂ 66 - 69%

Al ₂ O ₃ about 6%

B ₂ O ₃ h - n%

RO (CaO + MgO) 13-1852

Na ₂ O about 5%

nslt

CaO percent by weight about 1.4 %

MgO weight percent

This glass has the following properties:

Temperature at viscosity 10 ² .. < 1566 ⁰ C

Temperature at viscosity 10 ³ ^ 13l6 ° C

Temperature at viscosity 10 ⁷ <= 927 ⁰ C

Liquidus temperature. <= 12O4 ° C

Temperature at viscosity 10 ³ ( ⁰ C) Liquidus temperature ( ⁰ C) - =: 112 ° C

Therm. Expansion coefficient - = 60 χ 10 "^ / ⁰ C. (0-300 ⁰ C) Preferred compositions within the abovementioned range

-26-

9 0 9-8 37/13 U

'909187

reiclis are shown in FIG. Dolomite lime was used as a source of CaO and MgO, corresponding to a weight per cent ratio of OaO to MgO of approximately 1.4. The preferred types of glasses are those types of glasses represented by the parallelogram in the middle part of the ternary diagram. The limits of this parallelogram were determined by evaluating the glass forming and tempering properties with regard to the heat treatment required for opalization. Glcs within this preferred composition range has excellent molding properties and is thermally opalized in a very short time at a relatively low temperature. It has been found that articles molded from these compositions can be opalized in a modified yellowing cycle. In these glass compositions, BpO ^ is the primary opalizing agent, and the tendency of the glass to opalize increases as the proportion of B0, increases.

The time and temperature for the opalization heat treatment of this glass is the same as the conventional tempering heat treatment light-weight glass objects largely match. This means that this type of glass can be heat treated at temperatures of about 565 ° C to 8 ^ 5 ° C in 15 minutes to about 8 Hours can be opalized. Preferably the opalization heat treatment carried out for economic reasons at temperatures between 76O ° C and 8150 ° C for about an hour.

The following tables give glass compositions that can be used within

909837 / 13U BAD ORIGfNAt

28 1909187 • Weight percent this preferred composition range are dependent about 5% the B "0, -part of: about 6% B ₂ O, proportion is about k%: 67-69% component 16-18 years Na ₂ O Al ₂ O ₃ Weight percent SiO ₂ about 5% RO (CaO + MgO) about 6% B ₂ O, proportion is about 6%: 66.5 -68.5% component 14.5 -I6.5 '* Na ₂ O Al ₂ O ₃ Weight percent SiO ₂ about 5% RO (Ca0 + MgO) about 6% BgO-z share is about 8% '. 66-68% component 13-15JC Na ₂ O Al ₂ O ₃ SiO ₂ RO (CaO + MgO)
-28-

909837 / 13U

BAD ORIDINAL

These types of glasses do not require any special melting and refining conditions and can be used in continuously operated gas firing ovens be melted at temperatures between 1425 ° C and 160 ° C. Common starting materials can be used, as can be seen from the following examples.

Embodiment 8

The raw materials

powdered flint 3967-9 ² I g

raw dolomite lime 2069.30 g

Soda ash 517.2 * 1 g

Boric anhydride 31 ^ .47 g

Aluminum oxide 362.17 g

are in a platinum crucible at a glass transition temperature of 1593 ° C in an electric furnace with mechanical stirring. The melting time is about 24 hours Ensure homogeneity.

A rod was drawn from the molten glass, from which test rods which were allowed to cool in ambient air. The test bars were clear and see-through and had the following Composition:

-29-

9 0 9 8 3 7 / T 314 BATH

3SL

"TlUFTfT

component

Weight percent

CaO

MgO

Ou. 0% ο, ί 10. 0% ι> ¹ year

Several of these rods were 15 & in. Long heat treatment At the end of this heat treatment, the Shl'.be were slightly opalescent (slightly clouded). The coefficient of thermal expansion in the temperature range from 0 ° C to
Hethods measured and was about 59 ₃ o χ 10

C v / urdf? with conventional -7 '

Other test bars of the same composition were heat treated at 315 ° C for 1 hour. At the end of this "Järrnebehandlung; - interpreted this an increase of the thermal expansion coefficient of about 1.3, the sample rods were evenly opal, uric .ler bhermisehe expansion coefficient was 50.4 χ 10 ^-7 / ° C (300 ⁰ C 0 ° C). ? ·

Example 9

After the composition according to Example 3, clear ₃ transparent test plates of about .8; nm thickness were placed by placing molten glass in a flat, fire-proof

-30 -

909837/1314

BATH

Tub was poured in the open air. The plates were different Subjected to opalization heat treatments in order to be able to carry out reflection measurements.

The heat treatment and appearance of the sample panels will continue described below. The optical reflection of the radiant energy in the visible wavelength range was determined by conventional photometric Procedure determined. The results are in piss. graphically represented.

Plate 1 heat treatment: none

Appearance: clear and transparent

Plate 2

Heat treatment. : half an hour at 815 C

Appearance: slight opalescence

Plate 3

Heat treatment for one hour at 815 ° C

Appearance: slight opalescence

Plate Jl

Heat treatment: eight hours at 815 ° C

Appearance: almost opal-opal

Plate 5

Heat treatment: two hours at 827 ° C

Appearance: opaque-opal

-31-

909837 / 13U

BATH ORIGINAL

JL

19U918T

These sample disks were ground and polished until the surface was smooth and the optical reflective properties were conventionally using a General Electric "Hardy" Model Spectrophotometer with a black Background determined. The results are shown in FIG. These curves show how the time and the temperature of the heat treatment can be varied to get the desired results to achieve optical properties in the glass according to the invention.

Embodiment 10

Following the procedure of Working Example 8, starting materials were obtained melted and test bars made. The glass had the following composition and properties:

SiO ₂ Al ₂ O ₃ CaO MgO Na ₂ OB ₂ O ₃

Temperature at viscosity 10

Temperature at viscosity 10 Temperature at viscosity 10 ^ '- * Liquidus temperature

Temperature at viscosity liquidus temperature

67 * ⁰ C 6% ⁰ C 9.3% ⁰ C 6.7% ⁰ C 5% ⁰ C 6% 1527 1274 8ii6 1177 97

Thermal. Expansion coefficient

58 χ 10 " ⁷ / ° C (0-300 ⁰ C)

-32-

909837 / 13U

BATH

• Ji

Tempering tests were carried out with these test bars and it was found that the test bars were slightly opalescent after tempering for one hour at 7 ^ 9 ° C. Further tests with rods of this composition were carried out and it was found that the rods became densely opaque-opal after a heat treatment of one hour at 821.degree. This shows ₃ that the tempering and opalizing heat treatment can be combined.

With certain glass compositions, however, it is possible to dispense with the subsequent heat treatment and opacity under the simple influence of the thermal condition that exists in casting. These types of glass are by theirs low expansion coefficient and chemical resistance characterized.

They correspond to the formula:

SiO 2 2 Al ^Ö 3 RO 0 (CaO + MgO) ^B 2 2 3 N / A 0

approximately 71% II ΙΟ * ! I 1235 ι) 3%

the weight ratio of CaO to MgO being 1.5.

This ratio is the most important for the properties of the glass cheapest and is equivalent to the lime and

-33-

909837 / 13U

Yes.

Magnesium content of the dolomite rock. Instead of the sodium oxide Other alkali metal oxides can also be used, though Lithium oxide bit promotes glazing at high temperatures.

These types of glass have the following properties;

Temperature at viscosity 1O ² 1650 ⁰ C

Melting temperature 1127 ° C-

4 2 Viscosity at melting temperature 10 ^J coefficient of expansion per ⁰ C

(between 0 ⁰ C and 300 ° C) ^. 45

Opalization of the glass occurs in a temperature range of a ₃ which is suitable for the purpose and is fully achieved if the glass transition temperature during cooling the Littleton point
(Viscosity 10 ^{7;> ü} ^) reached. On the other hand, the opalization disfigures during the casting process; it occurs easily when the molten glass is drawn into the open air.

90 9837

BAO ORIGINAL

Claims (1)

JS 2H. 1909187 SiO ₂ that they essentially 10 - 76 Patent attorneys
Dr. Ing.H Hegendank
Owens-Il linois, Inc. Dipt- ": .Ί- Η · ^ * ^{u <} * February 1969 Al ₂ O ₃ r 11 12th Dipt- · '' - ■ ": '- · ·" ■ - ^
hO5 Madison Avenue «Man = -» "' ¹ · ¹ * '.'- mvA *** · **
Tel. 5 30C ^ ⁸ *
Toledo, Ohio, USA Attorney File M-637 B ₂ O ₃
CaO Weight percent 0 - 13th
20th HCO 55 - 15th Claims Ka ₂ O 1.5 - -95 11th (Yj Thermally opalescent alkaline earth aluminum silicate glass K ₂ O 0 -
5 - 5 sammenetzui.j5 _a characterized ₃ 0 - having: 1 - component 0 - 30th Li ₂ O <= 2 with 5 (CaO + HgO) (Na ₂ 0 + K ₂ O) * Weight percent B ₂ C =, Weight percent Na ₂ O (SiC ₂₊ Al ₂ O ₃₊ B ₂ O ₃₊ CaO ₊ HGO ₊ Na ₂ O) 9Q9837V13U ORIGINAL BATHROOM. M _ 2. Composition according to claim I _3, characterized in that ■: 1 (. Essentially comprises: Weight percent Inventory tc31 . «! IC. Λ1..Ο-
CJ V ₅ CaO MgO Ka., O (CaO + 60 - 70 H - 8th 1 - 9 6th - 16 ή - 12 3 - 7th 14th - 21 8th Weight percent B., O ₇ . Weight percent Na ₂ O 0) 3. Composition according to claim 1 or 2, characterized j that it has: Ingredient percentages by weight SiO ₂ 66 -69 Al ₂ O ₃ approximately 6th B ₂ O ₃ JS- - 8th CaO + MgO 13th - 18th Ka ₂ O approximately nit Weight percent · \ · _0 approximately HgO weight per:. · ¹ ■: - ! i 09837/13 ΐ 4 BAD ORfGiNAt JIf SiO ₂ SiO ₂ -3- 1909187 ^ r 1316 ° C and the properties Al ₂ O ₃ Al ₂ O ₃ ^ 12Ok ° C Temperature at viscosity 10 " ⁵ B ₂ O ₃ B ₂ O ₃ * c 112 ° C Liquidust temperature CaO + MgO CaO + MgO <: 6ox iG ~ ⁷ / ° c (o-3oo ° c). Temperature at viscosity ΙΟ ³ (
- liquidus temperature (C) Ma ₂ O Na ₂ O characterized ₅ that Therm. Expansion coefficient 5. Composition according to claim 3 ^l \. Composition mch claim 3, that it has: Weight percent it has: component 67-69% component about 6% about H% 16-18% efcwa 5% or H ₃ characterized by Weight percent $ 66.5 - 68 _{3 5} about 6% about 6% IH, 5 - 16.53 " about 5% BATH ORIGINAL T909187 6. Composition according to claim 3 _5, characterized in that it comprises: component SiO, B ₂ O ₃ CaO + MgO Na ₂ O Weight per ounce 66-6855 about 6% ■■ · "■ -about 8 % 13 - 1556 about 5% - 7. Composition according to one of claims 1 or 2, characterized characterized in that it has: Component. CaO + MgO Ma ₂ O CaO and a ~~ ratio of Weight percent 7136 H 105 «1256 3% 1.5 A method for producing opal glass objects from the composition: according to one of Claims 1 to I _3, characterized in that a glass object is formed from the composition and an in situ phase separation is brought about by thermal means, through which the finished glass object becomes opal. -4- 909837 / 13U 9. Method according to auisi rucii H, thereby * -el-: eiij «: - eieijiie1 ,. that the in situ plasmid removal by warming the object at a temperature · £ wi:; c · jc-ii ttwa · ( ^{l r} C and 90 ° C for a period of time before, about J | 5 l-iiiä. to t-tw; 64 hours will. 10.Verfahrer nacli claim Q. ilaüiu-cii {-? 'J ei leans 3 "in that the ^r-IEMI eraluri" ereieil jv between about ^{l l.}} Wipe ° C and feio ° C and the time period 1 unjrefSlir 15 ii3n. lincj is about 8 hours. .Glassgegensi and j according to the method ii. "-« - h eJnei »of the claims ^f ? To Ii) manufactured HUJ ^{i <} Je. 909837/13 BA & ORlOLMAL. TO Blank page