US3912481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for making alkali metal silicate thermoplastic materials
Assignee: Corning Glass Works
•
Filing: 1974-02-25
•
Granted: 1975-10-14
•
Expires: 1994-02-25
Abstract
Abstract This invention is concerned with the production of inorganic silicate materials which exhibit properties akin to the desirable characteristics of high-polymer organic plastics. Thus, the materials can demonstrate resilience and impact resistance. They are suitable for being thermoplastically formed at relatively low temperatures. They are strong and exhibit relatively good chemical durability, this latter property being capable of further improvement through surface treatments. This invention contemplates hydrating certain alkali metal-containing silicate glasses and thereafter carefully dehydrating the glass to maintain a water content therein within a specified range of concentrations.
Inventors
- 👤 Roger F Bartholomew
- 👤 Harold F Dates
- 👤 Stanley D Stookey
- 👤 Walter H Tarcza
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 09:39
CPC Classifications
C; C03; C03C; C03C21/00; C03C11/00; C03C11/007; C03C12/00; C03C23/00; C03C4/00
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
155 words
A METHOD FOR MAKING A GLASS BODY EXHIBITING THERMOPLASTIC PROPERTIES WHICH COMPRISES THE STEPS OF: A. HYDRATING A GLASS BODY CONSISTING ESSENTIALLY, IN MOLE PERCENT ON THE OXIDE BASIS, OF ABOUT 3-25$ NA2O AND/OR K2O AND 50-95% SIO2, THE SUM OF THOSE CONSTITUENTS CONSTITUTING AT LEAST 55% OF THE TOTAL COMPOSITION, BY EXPOSING SAID BODY TO A H2O-CONTAINING GASEOUS ENVIRONMENT HAVING A RELATIVE HUMIDITY OF AT LEAST ABOUT 75% AT A TEMPERATURE OF AT LEAST ABOUT 100*C, FOR A PERIOD OF TIME SUFFICIENT TO DEVELOP AT LEAST A SURFACE PORTION WHICH IS ESSENTIALLY SATURATED WITH WATER, AND, THEREAFTER, B. DEHYDRATING SAID BODY THROUGH CONTACT THEREOF WITH A GASEOUS ENVIRONMENT WHEREIN THE RELATIVE HUMIDITY IS LESS THAN ABOUT 90% OF THAT EMPLOYED IN SAID HYDRATION STEP FOR A PERIOD OF TIME SUFFICIENT TO REDUCE THE WATER CONTENT AT LEAST WITHIN SAID SURFACE PORTION BUT LEAVING AN EFFECTIVE AMOUNT THEREIN TO IMPART THE DESIRED THERMOPLASTIC PROPERTIES THERETO.
Claim 2
Independent Claim
155 words
A METHOD FOR MAKING A GLASS BODY EXHIBITING THERMOPLASTIC PROPERTIES WHICH COMPRISES THE STEPS OF: A. HYDRATING A GLASS BODY CONSISTING ESSENTIALLY, IN MOLE PERCENT ON THE OXIDE BASIS, OF ABOUT 3-25$ NA2O AND/OR K2O AND 50-95% SIO2, THE SUM OF THOSE CONSTITUENTS CONSTITUTING AT LEAST 55% OF THE TOTAL COMPOSITION, BY EXPOSING SAID BODY TO A H2O-CONTAINING GASEOUS ENVIRONMENT HAVING A RELATIVE HUMIDITY OF AT LEAST ABOUT 75% AT A TEMPERATURE OF AT LEAST ABOUT 100*C, FOR A PERIOD OF TIME SUFFICIENT TO DEVELOP AT LEAST A SURFACE PORTION WHICH IS ESSENTIALLY SATURATED WITH WATER, AND, THEREAFTER, B. DEHYDRATING SAID BODY THROUGH CONTACT THEREOF WITH A GASEOUS ENVIRONMENT WHEREIN THE RELATIVE HUMIDITY IS LESS THAN ABOUT 90% OF THAT EMPLOYED IN SAID HYDRATION STEP FOR A PERIOD OF TIME SUFFICIENT TO REDUCE THE WATER CONTENT AT LEAST WITHIN SAID SURFACE PORTION BUT LEAVING AN EFFECTIVE AMOUNT THEREIN TO IMPART THE DESIRED THERMOPLASTIC PROPERTIES THERETO.
Claim 3
Dependent Claim
23 words
A method according to claim 1 wherein said glass body is hydrated through exposure to a H2O-containing gaseous environment fully saturated with steam.
Claim 4
Dependent Claim
28 words
A method according to claim 1 wherein said glass body is hydrated through exposure to a temperature between about 100*C. and the softening point of the glass body.
Claim 5
Dependent Claim
24 words
A method according to claim 1 wherein said glass body is hydrated through exposure for a period of time ranging between about 0.25-96 hours.
Claim 6
Dependent Claim
24 words
A method according to claim 1 wherein said hydrated glass body has at least a surface portion containing about 5-35% by weight of water.
Claim 7
Dependent Claim
32 words
A method according to claim 1 wherein said glass body is dehydrated through contact with a gaseous environment having a relative humidity of about 0-90% of that employed in said hydration step.
Claim 8
Dependent Claim
33 words
A method according to claim 1 wherein said glass body is dehydrated through contact with a gaseous environment having a H2O pressure of less than 100 psi and a temperature higher than 200*C.
Claim 9
Dependent Claim
21 words
A method according to claim 6 wherein said gaseous environment contains acidic vapors to enhance the chemical durability of the glass.
Claim 10
Dependent Claim
27 words
A method according to claim 1 wherein said glass is dehydrated through contact with said gaseous environment for a period of time ranging between about 0.25-72 hours.
Claim 11
Dependent Claim
39 words
A method according to claim 1 wherein said glass body is dehydrated at a temperature approximating that of the initial exposure but at a relative humidity reduced to less than about 90% of that employed in said hydration step.
Claim 12
Dependent Claim
44 words
A method according to claim 1 wherein said glass body is dehydrated at a temperature lower than that of the initial exposure and also a reduced H2O pressure to yield a relative humidity less than about 90% of that utilized in said hydration step.
Claim 13
Dependent Claim
50 words
A method according to claim 1 wherein said glass body is dehydrated at a temperature higher than that of the initial exposure and also maintaining, raising, or lowering the H2O pressure but wherein the relative humidity is reduced to less than about 90% of that employed in said hydration step.
Claim 14
Dependent Claim
25 words
A method according to claim 1 wherein said dehydrated glass body has at least a surface portion containing at least about 1% by weight water.
Claim 15
Dependent Claim
23 words
A method according to claim 1 wherein said dehydrated glass body has at least a surface portion containing about 3-12% by weight water..
Claim 16
Dependent Claim
53 words
A method according to claim 1 wherein said surface portion has a lower water content than the interior portion such that said surface portion will have a lower coefficient of thermal expansion than said interior portion whereby, when said glass body is cooled to room temperature, said surface portion will be under compression.
Claim 17
Dependent Claim
48 words
A method according to claim 1 wherein crystals are developed within said surface portion having a coefficient of thermal expansion lower than that of the interior portion of the glass body whereby, when said glass body is cooled to room temperature, said surface portion will be under compression.
Claim 18
Dependent Claim
35 words
A method according to claim 1 wherein crystals having a long platy morphology are developed throughout said glass body whereby the mechanical strength of the body is enhanced and the appearance thereof is rendered translucent-to-opaque.
Claim 19
Dependent Claim
78 words
A method for forming bulk shapes from glass particles made in accordance with claim 1 exhibitng thermoplastic properties in which comprise the steps of: a. sizing said glass particles to pass a No. 5 United States Standard Sieve; b. forming a mass of said particles to a shape of a desired configuration under pressure and at a temperature ranging from above the freezing point of water to about 500*C., and then c. bringing said shape to room temperature.
Claim 20
Dependent Claim
18 words
A method according to claim 18 wherein said glass particles pass a No. 40 United States Standard Sieve.
Claim 21
Dependent Claim
18 words
A method according to claim 18 wherein said mass of particles is formed at temperatures between about 100*-400*C.
Claim 22
Dependent Claim
28 words
A method according to claim 18 wherein during or after said forming step at least a surface portion of said shape is dehydrated to an essentially anhydrous state.
Claim 23
Independent Claim
149 words
A method for making a foamed glass body which comprises the steps of: a. hydrating a glass body consisting essentially, in mole percent on the oxide basis, of about 3-25% Na2O and/or K2O and 50-95% SiO2, the sum of those constituents at least 55% of the total composition, by exposing said body to a H2O-containing gaseous environment having a relative humidity of at least about 75% at a temperature at which the hydrated glass is in a softened condition for a period of time sufficient to develop at least a surface portion which is essentially saturated with water; and, thereafter; b. rapidly dehydrating said body in a softened condition through contact thereof with a gaseous environment wherein the relative humidity is less than about 90% of that employed in said hydration step for a period of time sufficient to reduce the water content at least within said surface portion.
Claim 24
Independent Claim
149 words
A method for making a foamed glass body which comprises the steps of: a. hydrating a glass body consisting essentially, in mole percent on the oxide basis, of about 3-25% Na2O and/or K2O and 50-95% SiO2, the sum of those constituents at least 55% of the total composition, by exposing said body to a H2O-containing gaseous environment having a relative humidity of at least about 75% at a temperature at which the hydrated glass is in a softened condition for a period of time sufficient to develop at least a surface portion which is essentially saturated with water; and, thereafter; b. rapidly dehydrating said body in a softened condition through contact thereof with a gaseous environment wherein the relative humidity is less than about 90% of that employed in said hydration step for a period of time sufficient to reduce the water content at least within said surface portion.
Claim 25
Dependent Claim
23 words
A method according to claim 22 wherein said glass body is hydrated through exposure to a H2O-containinG gaseous environment fully saturated with steam.
Claim 26
Dependent Claim
32 words
A method according to claim 22 wherein said glass body is dehydrated through contact with a gaseous environment having a relative humidity of about 0-90% of that employed in said hydration step.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-10-13 | 1979-04-14 | 1979-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-10-13 | 1983-04-14 | 1983-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-10-13 | 1987-04-14 | 1987-10-14 | $7700.00 | Window Closed / Lapsed |