US2692209A - Bulb coating process - Google Patents

Bulb coating process Download PDF

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US2692209A
US2692209A US351985A US35198553A US2692209A US 2692209 A US2692209 A US 2692209A US 351985 A US351985 A US 351985A US 35198553 A US35198553 A US 35198553A US 2692209 A US2692209 A US 2692209A
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coating
envelope
bulb
suspension
neck
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US351985A
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Jr August E Binder
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General Electric Co
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General Electric Co
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
    • H01J9/20—Manufacture of screens on or from which an image or pattern is formed, picked up, converted or stored; Applying coatings to the vessel
    • H01J9/22—Applying luminescent coatings
    • H01J9/221—Applying luminescent coatings in continuous layers
    • H01J9/223—Applying luminescent coatings in continuous layers by uniformly dispersing of liquid

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  • VLowPezssue A02 His tt Patented Oct. 19, 1954 BULB COATING PROCESS August E. Binder, Jr., Mentor-on-the-Lake, Ohio,
  • My invention relates in general to a method of interiorly coating vitreous envelopes, such as lamp bulbs and the like, having a single opening thereinto, and especially to a method of applying a luminescent material to the inner surface of a selected portion of such envelopes.
  • Certain types of fluorescent lamps in general use at present employ a glass enclosure envelope or bulb having a bulbous portion provided with tubular extensions at its opposite ends one of which is closed off and the other of which is open at its outer end to form the neck portion of the bulb, the inner surface of the bulbous portion of the bulb being provided with a coating of fluorescent material while the tubular extensions are left clear.
  • the limiting or cut-01f edges of such fluorescent phosphor coatings be as straight as possible around the bulb and not of wavy or otherwise irregular character.
  • the outer rim endof the neck portion of such bulbs normally is of irregular form with sharp and jagged edges such as preclude the use of a conventional pressure upflush method of applying the coating to the bulb wall by reason of the difficulty of forming an airtight seal with such irregular edges, the formation of phosphor coatings with more or less straight cut-off edges heretofore has been a difiicult and inconvenient operation to perform, the method previously in use having been to first coat the entire inner surface of the bulb with the phosphor material and to then remove the coating from the tubular extensions of the bulb by a hand operation such as by brushing or wiping.
  • Another object of my invention is to provide an improved method of applying an internal fluorescent coating to the intermediate portion only of a tubular lamp envelope having an opening at one end only, whereby the cut-off edges of the coating are formed substantially straight.
  • a coating of fluorescent material is first applied to the inner wall of the lamp envelope extending inwardly from the open neck end thereof to the desired level for the innermost cut-off edge of the coating, by suction of a suspension of the fluorescent coating material upwardly into the envelope to the said level, immediately followed by washing of the fluorescent coating off the neck end portion of the envelope up to the desired lower cut-ofi level for the coating while simultaneously directing air through the envelope to rapidly dry the remaining coating on the bulb wall before it has an opportunity to drain therefrom such as would result in the formation of undesirably thin and non-uniform coatings.
  • Fig. 1 is a vertical section through a lamp envelope and associated apparatus employed to perform the first or coating application step of the method comprising my invention
  • Fig. 2 is a vertical section through the envelope and associated apparatus employed to perform the second step of the method comprising my invention wherein the portion of the coating on the lower or neck section of the envelope is removed and the remainder of the coating on the envelope is dried in place on the envelope wall.
  • the invention is herein described and illustrated with reference to the formation of an internal coating of fluorescent material on a selected intermediate portion of the length of a tubular glass envelope or bulb i which is closed at one end but open at the other end, the particular bulb illustrated having an enlarged ovalshaped or bulbous center portion 2 provided with cylindrical extensions 3 and 4 at its opposite ends, the extension 3 being open at its outer end and constituting the neck portion of the lamp envelope and the other extension 4 being closed oif at its outer end by an end closure wall 5. It should be understood, however, that the invention can be utilized to apply any coating material of the type which can be flushed onto the surface to be coated, and that it is applicable to the coating of envelopes of shapes other than tubular which have a single entrance opening thereinto.
  • the 'portion of the inner bulb surface extending from the open end 6 of the neck portion 3 inwardly to the innermost cut-off line i desired for the final coating is first flush-coated with a layer 8 (Fig. 2) of fluorescent material by suction of a suspension of a fluorescent material upwardly into the bulb while the latter is positioned with its open neck end down.
  • a layer 8 Fig. 2
  • the neck end 3 of the bulb is placed over a vertical suction tube 9 extending upwardly from the bottom wall Ii) of a container I I filled with the coating suspension I2 to be applied to the bulb wall, the bath of coating suspension I2 being exposed to atmospheric pressure.
  • the phosphor coating suspension: IZ- may be any of the .types customs. arily employed in fluorescent lamp manufacture for applying coatings of fluorescent material to the walls of the lamp envelopes, such phosphors-c suspensions usually comprising a fluorescent phosphor powder suspended in a suitable binder such as nitrocellulose dissolvedina'suitablersola' vent or thinner such as butyl acetate-or amyl' I acetate, with or without naphtha, for instance.
  • the vertical suction tube 9 is openatitsupper. end and is joined at its lower end to the bottom wall IQ of the container I I in a liquid-tight man: ner. The bulb I is moved down over the vertical suction-tube 3 until the upper end I3 oithelatter.
  • the bulb is located above the. innermost. or: upper-:cut-oih: level-SI for the coatingv anduntilthe lower neck end 3 of the bulb iscompletely submerged in-the-i coating :suspension bath I2 .a sufficient distance to remain submerged when .part of" the -coating suspension I2 inthe fcontainer'. II is drawn up..- into the. bulb to. the .-desir.ed. upper cut-off level] for the-coating.
  • the bulb may beconveniently supported in place by-resting the end.
  • neck end 30f the bulb up off -the bottorn wallzI of thecontainer Ii so-as to. permit free flow of the coating suspension :,I2 fromitheacontainen. into the bulb'neck-3.
  • the suction tube -9 come municates .at its lower end with -.a :conduit,'or pipe. I4 which is. adapted-tobetconnectedby 'a.
  • valve I5 in the said conduit, either to a source;- of vacuum,.oralternatively to the atmosphere so as to vent the suctiontube 9..-
  • the upper end or rim I3.of.the suction tube 9 is-suitably notched-.- as indicated at I6 -to provide passageways intere connecting theninterior of, thertubeii with the interior. space of the bulb.
  • the bulb will. produce. a .perfectly. smooth. and straight .upper. cut-ofiedge around the bulb defining a planenormal .to the bulb. axis, if..care is. taken .to see that the bulb-is supported on the suction tube 3 I 4 in true vertical position during the coating application operation.
  • the bulb is carefully lifted off the suction tube 9 so as not to mar the coating deposited on the bulb wall, and the said coating 8 then rapidly dried and set in place-by the .passageaofgza low velocity air current through the bulb to thereby minimize the drainage of the wet coating downwardly along the bulb wall such as would cause the coating to..thin. outwith resulting formation of an undesirably thin and non-uniform coating.
  • theneck portion 3 of the bulb is to be also'leftclear or free of coating, the portion of the phosphor coating on the neck portion 3 of the bulb. I isv suitably removed.
  • this phosphor coating removal operation is preferably performed simultaneously with the air drying of the coating on the-bulbous portion ⁇ .of-i-the-e-bulb.
  • I is. immersed. up to the: desired lowercut-ofi level;.-I'I ina bath 18 ;(Fig.;; 2) of, thinnermaterial suchlas customarily employed as a solvent.
  • thinnermaterial suchlas customarily employed as a solvent.
  • The-bulb I may ,be supportedrin -proper. position... relative to. the thinnerbath .I8' to effect theede sired extent of immersion-of. the bulb neck there-" in by restingthe bulbous portion .2 of the-bulb on::
  • OffthE-jn bulb I is immersed in the.thinnerbathbm lowe velocity air, which -:may- :be heated .if :desired; is discharged into then-interior. spacer-of the:.-bulb;.--
  • the bulb as indicated by the arrows in Fig. 2, where it comes in contact with and dries the phosphor coating 8 on the inner surface of the bulb wall.
  • the air stream passes out of the bulb through the annular space between the air inlet tube 22 and the wall 25 of the central passageway 23 in the toroidal container [9.
  • the bulb When the phosphor coating 8 on the bulb wall has been suificiently dried and set in place thereon, the bulb is withdrawn from the thinner bath It in the container [9 to thereby complete the coating operation.
  • the method of applying a coating of powdered material to the inner surface of a selected portion of the length of an envelope having an open-ended neck portion providing the only opening thereinto comprises inserting the envelope neck end down into a bath comprising a suspension of the coating material exposed to atmospheric pressure to completely submerge the open end of the said envelope neck portion in the said suspension bath, withdrawing the air in said envelope from a region adjacent the top thereof to create a suction therein and draw the said coating suspension up into the envelope, venting the interior space of the envelope above the coating suspension therein to the atmosphere when the column of coating suspension attains the desired predetermined upper cut-off level for the coating, to cause the column of coating suspension in the envelope to recede therefrom, and immediately immersing the neck end portion of the envelope up to the desired predetermined lower cut-ofi level for the coating in a thinner for the said coating suspension while simultaneously passing a low velocity air stream through the interior space of the envelope above the thinner therein to dry and set in place the coating deposited on the inner wall of the envelope.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Formation Of Various Coating Films On Cathode Ray Tubes And Lamps (AREA)
  • Vessels And Coating Films For Discharge Lamps (AREA)

Description

Oct. 19, 1954 5 JR 2,692,209"
BULB COATING PROCESS Filed April 29, 1953 V EATMOSPHLQ:
7b VACUUM z0- z & j 1 1 7 j I I 25 :7 lnven torz 4 W I Au us t E.Binder-, JTT,
22* b MK 3 A) :J
VLowPezssue: A02 His tt Patented Oct. 19, 1954 BULB COATING PROCESS August E. Binder, Jr., Mentor-on-the-Lake, Ohio,
assignor to General Electric Company, a corporation of New York Application April 29, 1953, Serial No. 351,985
3 Claims.
My invention relates in general to a method of interiorly coating vitreous envelopes, such as lamp bulbs and the like, having a single opening thereinto, and especially to a method of applying a luminescent material to the inner surface of a selected portion of such envelopes.
Certain types of fluorescent lamps in general use at present employ a glass enclosure envelope or bulb having a bulbous portion provided with tubular extensions at its opposite ends one of which is closed off and the other of which is open at its outer end to form the neck portion of the bulb, the inner surface of the bulbous portion of the bulb being provided with a coating of fluorescent material while the tubular extensions are left clear. For satisfactory appearance it is desirable that the limiting or cut-01f edges of such fluorescent phosphor coatings be as straight as possible around the bulb and not of wavy or otherwise irregular character. However, because the outer rim endof the neck portion of such bulbs normally is of irregular form with sharp and jagged edges such as preclude the use of a conventional pressure upflush method of applying the coating to the bulb wall by reason of the difficulty of forming an airtight seal with such irregular edges, the formation of phosphor coatings with more or less straight cut-off edges heretofore has been a difiicult and inconvenient operation to perform, the method previously in use having been to first coat the entire inner surface of the bulb with the phosphor material and to then remove the coating from the tubular extensions of the bulb by a hand operation such as by brushing or wiping.
It is an object of my invention, therefore, to
provide an improved method of applying a coating to a selected area of the inner surface of a lamp envelope or other hollow article having a single opening thereinto, which method is easy and convenient to perform and requires a minimum expenditure of time.
Another object of my invention is to provide an improved method of applying an internal fluorescent coating to the intermediate portion only of a tubular lamp envelope having an opening at one end only, whereby the cut-off edges of the coating are formed substantially straight.
According to one aspect of the invention, a coating of fluorescent material is first applied to the inner wall of the lamp envelope extending inwardly from the open neck end thereof to the desired level for the innermost cut-off edge of the coating, by suction of a suspension of the fluorescent coating material upwardly into the envelope to the said level, immediately followed by washing of the fluorescent coating off the neck end portion of the envelope up to the desired lower cut-ofi level for the coating while simultaneously directing air through the envelope to rapidly dry the remaining coating on the bulb wall before it has an opportunity to drain therefrom such as would result in the formation of undesirably thin and non-uniform coatings.
Further objects and advantages of my invention will appear from the following description of a species thereof and from the accompanying drawing in which:
Fig. 1 is a vertical section through a lamp envelope and associated apparatus employed to perform the first or coating application step of the method comprising my invention, and
Fig. 2 is a vertical section through the envelope and associated apparatus employed to perform the second step of the method comprising my invention wherein the portion of the coating on the lower or neck section of the envelope is removed and the remainder of the coating on the envelope is dried in place on the envelope wall.
The invention is herein described and illustrated with reference to the formation of an internal coating of fluorescent material on a selected intermediate portion of the length of a tubular glass envelope or bulb i which is closed at one end but open at the other end, the particular bulb illustrated having an enlarged ovalshaped or bulbous center portion 2 provided with cylindrical extensions 3 and 4 at its opposite ends, the extension 3 being open at its outer end and constituting the neck portion of the lamp envelope and the other extension 4 being closed oif at its outer end by an end closure wall 5. It should be understood, however, that the invention can be utilized to apply any coating material of the type which can be flushed onto the surface to be coated, and that it is applicable to the coating of envelopes of shapes other than tubular which have a single entrance opening thereinto.
To provide an internal fluorescent coating on an intermediate portion of the length of the bulb I, for instance on the bulbous portion 2 only, by the method according to the invention, the 'portion of the inner bulb surface extending from the open end 6 of the neck portion 3 inwardly to the innermost cut-off line i desired for the final coating, is first flush-coated with a layer 8 (Fig. 2) of fluorescent material by suction of a suspension of a fluorescent material upwardly into the bulb while the latter is positioned with its open neck end down. For this purpose, the neck end 3 of the bulb is placed over a vertical suction tube 9 extending upwardly from the bottom wall Ii) of a container I I filled with the coating suspension I2 to be applied to the bulb wall, the bath of coating suspension I2 being exposed to atmospheric pressure. The phosphor coating suspension: IZ-may be any of the .types customs. arily employed in fluorescent lamp manufacture for applying coatings of fluorescent material to the walls of the lamp envelopes, such phosphors-c suspensions usually comprising a fluorescent phosphor powder suspended in a suitable binder such as nitrocellulose dissolvedina'suitablersola' vent or thinner such as butyl acetate-or amyl' I acetate, with or without naphtha, for instance. The vertical suction tube 9 is openatitsupper. end and is joined at its lower end to the bottom wall IQ of the container I I in a liquid-tight man: ner. The bulb I is moved down over the vertical suction-tube 3 until the upper end I3 oithelatter. is located above the. innermost. or: upper-:cut-oih: level-SI for the coatingv anduntilthe lower neck end 3 of the bulb iscompletely submerged in-the-i coating :suspension bath I2 .a sufficient distance to remain submerged when .part of" the -coating suspension I2 inthe fcontainer'. II is drawn up..- into the. bulb to. the .-desir.ed. upper cut-off level] for the-coating. The bulb may beconveniently supported in place by-resting the end. closure wall 5 .of its top extension 4 on .the upper end: I3 .of'i the-suctiontube- 9; the said tube-for such-pur v pose being of sufiicient height to iocate-the-open". neck end 30f the bulb up off -the bottorn wallzI of thecontainer Ii so-as to. permit free flow of the coating suspension :,I2 fromitheacontainen. into the bulb'neck-3. The suction tube -9 come municates .at its lower end with -.a :conduit,'or pipe. I4 which is. adapted-tobetconnectedby 'a. valve I5: in the said conduit, either to a source;- of vacuum,.oralternatively to the atmosphere so as to vent the suctiontube 9..- The upper end or rim I3.of.the suction tube 9 is-suitably notched-.- as indicated at I6 -to provide passageways intere connecting theninterior of, thertubeii with the interior. space of the bulb.
With the bulb I rested inposition .on. the top I3.,of. the suctionxtubeil and. its lower neck "end v=. 3 immersedinthe coating. suspension. i2 lll'fl'lherz container. I I, as shown. in Fig. -.1,,-thev valve -I5 is set so. asv to connect .the -,suction...tubea9 :to: the source of vacuum. The .resulting suction: createdinthetube-Q and bulb I thendrawsrthei coatingsuspension; I 2..in..the containeral I -up;,into a the, :junctionbetween the enlarged :bulbous pore, i
tion,,2 Qanduthe -.upper cylindrical; extensionzr 01 the.-.bu1b,..the vacuum; is I shut {Ofi by means .of thevalve I5 and the suctiontubec then connected.- instead .to theatmosphere by the zvalve-so as to, vent the tube 9 and the interior of the bulb,-.asa resultof. ,which the column of coatingsuspen sion. in the. bulb recedes approximately to. :its original starting level equalized with that of the coating-suspension I2 outside the bulb. It..will..f. beobvious thatby the useof-the above-described. particularup-fiush coating operation the rising; column..of;.coating. suspensionin the bulb will. produce. a .perfectly. smooth. and straight .upper. cut-ofiedge around the bulb defining a planenormal .to the bulb. axis, if..care is. taken .to see that the bulb-is supported on the suction tube 3 I 4 in true vertical position during the coating application operation.
Immediately after the coating 8 has been thus flushed onto the interior wall of the bulb I, the bulb is carefully lifted off the suction tube 9 so as not to mar the coating deposited on the bulb wall, and the said coating 8 then rapidly dried and set in place-by the .passageaofgza low velocity air current through the bulb to thereby minimize the drainage of the wet coating downwardly along the bulb wall such as would cause the coating to..thin. outwith resulting formation of an undesirably thin and non-uniform coating. In addition,..vvherev theneck portion 3 of the bulb is to be also'leftclear or free of coating, the portion of the phosphor coating on the neck portion 3 of the bulb. I isv suitably removed.
In accordance with the invention, this phosphor coating removal operation is preferably performed simultaneously with the air drying of the coating on the-bulbous portion} .of-i-the-e-bulb. For such-.pur.pose-.-.the phosphor coated neckiend; portion: 3 of the bulb. I is. immersed. up to the: desired lowercut-ofi level;.-I'I ina bath 18 ;(Fig.;; 2) of, thinnermaterial suchlas customarily employed as a solvent. for the nitrocellulose or other, binder used in..phosphor coatings, exampleseof which thinnerxmateria-l. have been. previously, mentioned, The, thinner. bath: l8 ris preferably contained in a toroidal-shaped container orcup: I9 intotheannular chamber ofawhichthe neck end 31of-thebu1blis inserted to .the. required; depth to veffect immersion. of ,;the.-.pl 1osphor-.coat. ingon the. bulb neckup to thedesired lower.cute:- ofielevel .II. which; for;.the.;particular..type::of..'. lamp. illustrated,gis located approximately et the: junction betweenthe enlarged-bulbous portion 2 .and .the cylindrical neck portion. 3 .ofithe bulb. The-bulb I may ,be supportedrin -proper. position... relative to. the thinnerbath .I8' to effect theede sired extent of immersion-of. the bulb neck there-" in by restingthe bulbous portion .2 of the-bulb on::
the upper annular rim.or end 20 of the; con-;-- tainer I9.. The-thinner bath-.lfi-rac-ts to imam tainin suspension and-thuswashthe phosphor coating'ofi the:bu1b neck .upto the level thereof. immersed in the thinner bath .so-that when the bulb neck is subsequently removed from the thine. ner bath the. said portion-of the bulb neck-.yvill be. left substantially clear, and the-:phosphon coah. ing 8 remaining on the. bulb. wallzwill bevformeda; witha smooth and straight lower .cut-ofiedged 11.1: around. the bulb. To maintaimthethinner bathe. I 8 in .the.:container; .I 9 aILthe: desired-lowers..cut;-..-- oil level IT for the coatings-and prevent -.it,-from.;. risingabove suchlevelby reason of-the. tendency of. the, phosphor; coating-washedeoif theeyvalls "of... successive gbulbs to. increase.-.-.-.the volume of their thinner .bath- I 8,. the zcontai-ner I 9 ..-is.; provided; with. a suitable overflow outlet-.orzspout-Z I.
During. the interval while. the-neck. end 3 OffthE-jn bulb I is immersed in the.thinnerbathbm lowe velocity air, which -:may- :be heated .if :desired; is discharged into then-interior. spacer-of the:.-bulb;.--
above thelevel of the thinner therein, preferably; intothe topregion of the: bulb within .thecylin-'-.-- drical .top extension 4 thereof fromra yerticalairi. f
the bulb, as indicated by the arrows in Fig. 2, where it comes in contact with and dries the phosphor coating 8 on the inner surface of the bulb wall. The air stream passes out of the bulb through the annular space between the air inlet tube 22 and the wall 25 of the central passageway 23 in the toroidal container [9.
When the phosphor coating 8 on the bulb wall has been suificiently dried and set in place thereon, the bulb is withdrawn from the thinner bath It in the container [9 to thereby complete the coating operation.
What I claim as new and desire to secure by Letters Patent of the United States is:
1. The method of applying a coating of powdered material to the inner surface of a selected portion of the length of an envelope having an open-ended neck portion providing the only opening thereinto, which method comprises inserting the envelope neck end down into a bath comprising a suspension of the coating material exposed to atmospheric pressure to completely submerge the open end of the said envelope neck portion in the said suspension bath, withdrawing the air in said envelope from a region adjacent the top thereof to create a suction therein and draw the said coating suspension up into the envelope, venting the interior space of the envelope above the coating suspension therein to the atmosphere when the column of coating suspension attains the desired predetermined upper cut-off level for the coating, to cause the column of coating suspension in the envelope to recede therefrom, and immediately immersing the neck end portion of the envelope up to the desired predetermined lower cut-ofi level for the coating in a thinner for the said coating suspension while simultaneously passing a low velocity air stream through the interior space of the envelope above the thinner therein to dry and set in place the coating deposited on the inner wall of the envelope.
2. The method as set forth in claim 1 wherein the said air stream is directed downwardly through the envelope from the top region thereof.
3. The method of applying a coating of powdered material to the inner surface of a selected portion of the length of an envelope having an open-ended neck portion providing the only opening into the envelope, which method comprises positioning the envelope neck end down over a vertically extending tube with the upper end of the said tube located above the desired upper cut-oil? line for the coating on the envelope and the open neck end of the envelope completely submerged in a bath comprising a suspension of the coating material, connecting the lower end of the said tube to a source of vacuum to create a suction in the tube and envelope and draw the said coating suspension up into the envelope, disconnecting the said tube from the vacuum source and venting it to the atmosphere when the rising column of coating suspension attains the said upper cut-off line for the coating, to cause the column of coating suspension in the envelope to recede therefrom, and then immediately placing the neck end of the envelope over a vertical air outlet tube upstanding from the bottom of a container filled with a liquid thinner for the said coating suspension and immersing the said neck end of the envelope in the said thinner up to the desired lower cut-off line for the coating on the envelope while simultaneously introducing a low velocity stream of air into the top region of the envelope, through a vertical air inlet tube extending through the said air outlet tube, to dry and set in place the coating deposited on the inner wall of the envelope.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,096,416 Weinhart Oct. 19, 1937 2,303,290 Michael Nov. 24, 1942 2,318,060 Cortese May 4, 1943

Claims (1)

1. THE METHOD OF APPLYING A COATING OF POWDERED MATERIAL TO THE INNER SURFACE OF A SELECTED PORTION OF THE LENGTH OF AN ENVELOPE HAVING AN OPEN-ENDED NECK PORTION PROVIDING THE ONLY OPENING THEREINTO, WHICH METHOD COMPRISES INSERTING THE ENVELOPE NECK END DOWN INTO A BATH COMPRISING A SUSPENSION OF THE COATING MATERIAL EXPOSED TO ATMOSPHERIC PRESSURE TO COMPLETELY SUBMERGE THE OPEN END OF THE SAID ENVELOPE NECK PORTION IN THE SAID SUSPENSION BATH, WITHDRAWING THE AIR IN SAID ENVELOPE FROM A REGION ADJACENT THE TOP THEREOF TO CREATE A SUCTION THEREIN AND DRAW THE SAID COATING SUSPENSION UP INTO THE ENVELOPE, VENTING THE INTERIOR SPACE OF THE ENVELOPE ABOVE THE COATING SUSPENSION THEREIN TO THE ATMOSPHERE WHEN THE COLUMN OF COATING SUSPENSION ATTAINS THE DESIRED PREDETERMINED UPPER CUT-OFF LEVEL FOR THE COATING, TO CAUSE THE COLUMN OF COATING SUSPENSION IN THE ENVELOPE TO RECEDE THEREFROM, AND IMMEDIATELY IMMERSING THE NECK END PORTION OF THE ENVELOPE UP TO THE DESIRED PREDETERMINED
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2832309A (en) * 1956-11-23 1958-04-29 Gen Electric Apparatus for interiorly coating lamp exhaust tubes
US3146124A (en) * 1961-06-29 1964-08-25 Sylvania Electric Prod Method of and apparatus for applying ignition paste in the manufacture of photoflash lamps
US3868264A (en) * 1973-03-21 1975-02-25 Corning Glass Works Method of applying light diffusing coating to interior of incandescent lamp envelope
US4151312A (en) * 1975-09-01 1979-04-24 U.S. Philips Corporation Making a cathode ray tube having a conductive coating on the inner surface with a sharply defined smooth edge
WO1983003140A1 (en) * 1982-03-04 1983-09-15 Medical & Scient Designs Method and apparatus for performing assays
US4965099A (en) * 1989-10-27 1990-10-23 Valco Cincinnati, Inc. Apparatus and method for selectively coating the inner surface of a hollow body
WO2013023748A1 (en) * 2011-08-12 2013-02-21 Technische Universität Dresden Optoelectronic component and method for treating the interior of a hollow body with a liquid

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2096416A (en) * 1933-12-27 1937-10-19 Bell Telephone Labor Inc Method of coating hollow receptacles
US2303290A (en) * 1941-06-28 1942-11-24 Sylvania Electric Prod Method of coating glass envelopes
US2318060A (en) * 1939-08-12 1943-05-04 Thomas M Cortese Method of applying luminescent material

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2096416A (en) * 1933-12-27 1937-10-19 Bell Telephone Labor Inc Method of coating hollow receptacles
US2318060A (en) * 1939-08-12 1943-05-04 Thomas M Cortese Method of applying luminescent material
US2303290A (en) * 1941-06-28 1942-11-24 Sylvania Electric Prod Method of coating glass envelopes

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2832309A (en) * 1956-11-23 1958-04-29 Gen Electric Apparatus for interiorly coating lamp exhaust tubes
US3146124A (en) * 1961-06-29 1964-08-25 Sylvania Electric Prod Method of and apparatus for applying ignition paste in the manufacture of photoflash lamps
US3868264A (en) * 1973-03-21 1975-02-25 Corning Glass Works Method of applying light diffusing coating to interior of incandescent lamp envelope
US4151312A (en) * 1975-09-01 1979-04-24 U.S. Philips Corporation Making a cathode ray tube having a conductive coating on the inner surface with a sharply defined smooth edge
WO1983003140A1 (en) * 1982-03-04 1983-09-15 Medical & Scient Designs Method and apparatus for performing assays
US4965099A (en) * 1989-10-27 1990-10-23 Valco Cincinnati, Inc. Apparatus and method for selectively coating the inner surface of a hollow body
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