NO135396B - - Google Patents
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- Publication number
- NO135396B NO135396B NO437/73A NO43773A NO135396B NO 135396 B NO135396 B NO 135396B NO 437/73 A NO437/73 A NO 437/73A NO 43773 A NO43773 A NO 43773A NO 135396 B NO135396 B NO 135396B
- Authority
- NO
- Norway
- Prior art keywords
- aluminum
- boron nitride
- refractory
- substrate
- heated
- Prior art date
Links
- 229910052782 aluminium Inorganic materials 0.000 claims description 35
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 35
- 229910052582 BN Inorganic materials 0.000 claims description 19
- PZNSFCLAULLKQX-UHFFFAOYSA-N Boron nitride Chemical compound N#B PZNSFCLAULLKQX-UHFFFAOYSA-N 0.000 claims description 19
- 239000000758 substrate Substances 0.000 claims description 13
- 238000000576 coating method Methods 0.000 claims description 8
- 239000011248 coating agent Substances 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 4
- 238000001556 precipitation Methods 0.000 claims description 2
- 229910052751 metal Inorganic materials 0.000 description 6
- 239000002184 metal Substances 0.000 description 6
- 238000010438 heat treatment Methods 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- 239000004411 aluminium Substances 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 239000010410 layer Substances 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 239000003575 carbonaceous material Substances 0.000 description 3
- 230000008020 evaporation Effects 0.000 description 3
- 238000001704 evaporation Methods 0.000 description 3
- 239000002985 plastic film Substances 0.000 description 3
- 239000011819 refractory material Substances 0.000 description 3
- 230000008016 vaporization Effects 0.000 description 3
- 150000001875 compounds Chemical class 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 239000002002 slurry Substances 0.000 description 2
- 238000009834 vaporization Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- BOTDANWDWHJENH-UHFFFAOYSA-N Tetraethyl orthosilicate Chemical compound CCO[Si](OCC)(OCC)OCC BOTDANWDWHJENH-UHFFFAOYSA-N 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 210000000056 organ Anatomy 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000002344 surface layer Substances 0.000 description 1
- 238000001771 vacuum deposition Methods 0.000 description 1
- 239000000080 wetting agent Substances 0.000 description 1
Classifications
-
- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23K—FODDER
- A23K50/00—Feeding-stuffs specially adapted for particular animals
- A23K50/40—Feeding-stuffs specially adapted for particular animals for carnivorous animals, e.g. cats or dogs
- A23K50/42—Dry feed
-
- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23K—FODDER
- A23K10/00—Animal feeding-stuffs
- A23K10/20—Animal feeding-stuffs from material of animal origin
- A23K10/22—Animal feeding-stuffs from material of animal origin from fish
-
- A—HUMAN NECESSITIES
- A23—FOODS OR FOODSTUFFS; TREATMENT THEREOF, NOT COVERED BY OTHER CLASSES
- A23K—FODDER
- A23K40/00—Shaping or working-up of animal feeding-stuffs
- A23K40/30—Shaping or working-up of animal feeding-stuffs by encapsulating; by coating
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Polymers & Plastics (AREA)
- Engineering & Computer Science (AREA)
- Food Science & Technology (AREA)
- Zoology (AREA)
- Animal Husbandry (AREA)
- Marine Sciences & Fisheries (AREA)
- Birds (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Biotechnology (AREA)
- Molecular Biology (AREA)
- Physiology (AREA)
- Fodder In General (AREA)
- Feed For Specific Animals (AREA)
- Physical Vapour Deposition (AREA)
- Meat, Egg Or Seafood Products (AREA)
Description
Apparat for påføring av belegg av aluminium på et bevegelig underlag ved utfelling av aluminiumdamper. Apparatus for applying a coating of aluminum to a moving surface by precipitation of aluminum vapors.
Foreliggende oppfinnelse angår et apparat for påføring av belegg av aluminium The present invention relates to an apparatus for applying aluminum coatings
på et bevegelig underlag ved utfelling av on a moving surface during deposition of
aluminiumdamper på dette, idet aluminium aluminum vapors on this, being aluminum
opphetes i høyvakuum til en temperatur av is heated in high vacuum to a temperature of
1200°C eller høyere, og aluminiumet som 1200°C or higher, and the aluminum which
skal fordampes er anbrakt i eller på et ildfast organ, og et bevegelig underlag, f.eks. to be evaporated is placed in or on a refractory body, and a movable surface, e.g.
papir eller plastplater eller andre artikler, paper or plastic sheets or other articles,
utsettes for dampene av aluminium. exposed to the vapors of aluminium.
Oppfinnelsen har som formål å forlenge The purpose of the invention is to extend
tiden i hvilken vakuumbelegning av aluminium på artikler kan utføres kontinuerlig, the time in which vacuum coating of aluminum on articles can be carried out continuously,
og uten avbrytelser for å skifte ut bæreren, and without interruptions to replace the carrier,
hvis fuktbare overflate tjener som underlag whose wettable surface serves as a substrate
for det smeltede aluminium som skal opphetes. Dette formål realiseres ved i det for the molten aluminum to be heated. This purpose is realized by in it
nevnte apparat å bruke et forbedret ildfast said apparatus to use an improved refractory
organ, som har en lang levetid når det utsettes for de høye temperaturer av aulmini-umet på 1200—1300°C, som må brukes ved organ, which has a long life when exposed to the high temperatures of the aluminum alloy of 1200-1300°C, which must be used in
slik påføring av aluminiumbelegg. such application of aluminum coating.
Ved fordampning av aluminium på et When vaporizing aluminum on a
underlag, som f. eks. papir og plastplater i substrate, such as paper and plastic sheets i
et vakuumkammer var det ett av de største a vacuum chamber it was one of the largest
problemer ved de tidligere prosesser at problems at the previous processes that
smeltet aluminium ved de nødvendige for-dampningstemperaturer tærer opp eller molten aluminum at the necessary evaporation temperatures corrodes or
ødelegger det ildfaste organ som aluminiumet er i kontakt med, hvorved prosessen destroys the refractory body with which the aluminum is in contact, whereby the process
ofte må avbrytes for å kunne skifte ut bære-organene. often have to be interrupted in order to be able to replace the bearing members.
Det er funnet at en understøttelses-overflate av bornitrid er meget motstands-dyktig mot smeltet aluminium når det opphetes og holdes ved en fordampningstempe-ratur på 1350°C, hvorved man kan bruke It has been found that a support surface of boron nitride is very resistant to molten aluminum when heated and held at an evaporation temperature of 1350°C, whereby one can use
meget lengere beleggningstider enn det hit- much longer occupancy times than here-
til har vært mulig. Bornitridet utgjør for-trinnsvis et overflatelag på et underlag av ildfast materiale, som kan bestå av et carbonholdig materiale eller av et ildfast materiale. Det ildfaste underlag kan være en leder eller en isolator, avhengig av den metode som brukes for opphetning av aluminium. Det ildfaste materiale kan velges fra en stor rekke metaller og forbindelser, idet det hovedsakelige krav er at det er istand til å motstå de høye temperaturer som tren-ges for fordampning av aluminium, og at det har et damptrykk på mindre enn 0,1 mikron Hg abs. ved 1300°C. to has been possible. The boron nitride preferably forms a surface layer on a substrate of refractory material, which may consist of a carbonaceous material or of a refractory material. The refractory substrate can be a conductor or an insulator, depending on the method used for heating the aluminium. The refractory material can be chosen from a large number of metals and compounds, the main requirement being that it is able to withstand the high temperatures needed for vaporization of aluminium, and that it has a vapor pressure of less than 0.1 micron Hg abs. at 1300°C.
For å belegge f. eks. papir- og plastplater eller -ark med aluminiumdamper må det flytende aluminium som opphetes til fordampning fukte underlaget eller bære-organet. Hvis det smeltede metall ikke fukter bæreren, vil metallet nemlig danne en kule, på lignende måte som en vanndråpe på en het komfyrplate. En slik metallkule kan ikke opphetes på en effektiv måte. Hvis det anvendes elektrisk induksjonsopphet-ning, vil kulene ble utsatt for rotasjons-energi, og vil spinne, og ofte i en slik grad at de kastes fra sitt underlag. Hvis elektrisk motstandsopphetning anvendes, er kon-taktarealet mellom kulen og underlags-flaten så lite at opphetningen vil bli meget lite effektiv. To cover e.g. paper and plastic plates or sheets with aluminum vapors, the liquid aluminum that is heated to vaporization must moisten the substrate or the carrier. If the molten metal does not wet the carrier, the metal will form a ball, in a similar way to a drop of water on a hot stove plate. Such a metal ball cannot be heated efficiently. If electric induction heating is used, the balls will be exposed to rotational energy, and will spin, and often to such an extent that they are thrown from their surface. If electric resistance heating is used, the contact area between the ball and the substrate surface is so small that the heating will be very inefficient.
En metallkule vil heller ikke danne damper på en tilfredsstillende måte. Dampene som utsendes fra den nedre del av den krumme kuleformede overflate, vil nemlig delvis bli oppfanget mellom kulen og dens underlag eller bærer. Når disse damper plut-selig unnviker, så medfører dette at smeltet aluminium vil bli slynget utover. Dette ut-slyngede aluminium vil brenne hull i underlaget som skal belegges, bestående f. eks. av papir og plastplater, slik at dette ødelegges, og hvis underlaget ikke er så varmefølsomt, utfelles aluminiumet på en utilfredsstil-lende måte, f. eks. i form av klumper. A metal ball will also not produce vapor satisfactorily. The vapors that are emitted from the lower part of the curved spherical surface will be partially captured between the sphere and its substrate or carrier. When these vapors suddenly escape, this means that molten aluminum will be flung outwards. This ejected aluminum will burn holes in the substrate to be coated, consisting of e.g. of paper and plastic sheets, so that this is destroyed, and if the substrate is not so heat-sensitive, the aluminum precipitates in an unsatisfactory way, e.g. in the form of lumps.
Som det av det foran anførte vil for-ståes, er det av avgjørende betydning at bæreren for aluminiumet fuktes av dette. As will be understood from the foregoing, it is of crucial importance that the support for the aluminum is moistened by this.
Det har nu vært alminnelig kjent at bornitrid ikke fuktes av smeltede metaller, og dette er anført i en rekke litteraturste-der, som her ikke skal omtales nærmere. Oppfinneren har nu imidlertid overras-kende nok funnet, at når aluminiumet er opphetet til over 1200°C, fukter det smeltede aluminium en bornitridoverflate meget godt, og det er denne erkjennelse som dan-ner grunnlaget for foreliggende oppfinnelse. It has now been common knowledge that boron nitride is not wetted by molten metals, and this is stated in a number of literature sources, which will not be discussed in more detail here. The inventor has now surprisingly found, however, that when the aluminum is heated to over 1200°C, the molten aluminum wets a boron nitride surface very well, and it is this realization that forms the basis of the present invention.
Når den ildfaste bærer består av carbonholdig materiale, kan bornitridbelegget påføres ved å presse mekanisk pulveret mot det carbonholdige underlag, eller det kan påføres i form av en pasta eller oppslemning, som senere tørkes. Eventuelt kan man bruke mekaniske gripeorganer som hjelper til å binde bornitridlaget til det ildfaste underlag, f. eks. kan det brukes tenger, trådnetting og lignende. When the refractory carrier consists of carbonaceous material, the boron nitride coating can be applied by mechanically pressing the powder against the carbonaceous substrate, or it can be applied in the form of a paste or slurry, which is later dried. Optionally, mechanical gripping devices can be used which help to bind the boron nitride layer to the refractory substrate, e.g. pliers, wire netting and the like can be used.
En foretrukket metode ifølge oppfinnelsen er illustrert i det følgende ved hjelp av et ikke begrensende eksempel. A preferred method according to the invention is illustrated in the following by means of a non-limiting example.
Eksempel. Example.
Det fremstillse en oppslemning ved å blande 5 g pulverformet bornitrid med noen få dråper av ethylsilikat til hvilket tilsettes en dråpe av et kommersielt fuktemiddel. Det tilsettes deretter tilstrekkelig vann til å danne en tykk pasta. Pastaen anbringes på den indre overflate og den øvre kant av en digel dannet av en blanding av grafitt og carbon. Man lar belegget tørke i luft ved 93 °C og oppheter deretter i en vakuumovn ved 130°C inntil gassutvikling er tilsluttet. Den således belagte digel fylles med aluminium anbragt i et høyvakuumkammer under vedkommende underlag som skal belegges, og den tjener som en kilde for aluminiumdamper ved høye temperaturer på 1300°C, idet den oppviser utmerket mot-standsevne mot smeltet aluminium. A slurry is prepared by mixing 5 g of powdered boron nitride with a few drops of ethyl silicate to which is added a drop of a commercial wetting agent. Sufficient water is then added to form a thick paste. The paste is placed on the inner surface and the upper edge of a crucible formed from a mixture of graphite and carbon. The coating is allowed to dry in air at 93 °C and then heated in a vacuum oven at 130 °C until gas evolution is connected. The thus coated crucible is filled with aluminum placed in a high vacuum chamber under the relevant substrate to be coated, and it serves as a source for aluminum vapors at high temperatures of 1300°C, as it exhibits excellent resistance to molten aluminum.
Bæreren fuktes meget godt, og grense-flaten mellom aluminiumet og bornitridet The carrier is wetted very well, and the interface between the aluminum and the boron nitride
er meget hård, muligens som et resultat av at aluminiumet og bornitridet ved de høye arbeidstemperaturer, inngår en kompleks aluminium-bomitrid-forbindelse. is very hard, possibly as a result of the fact that the aluminum and boron nitride at the high working temperatures form a complex aluminium-bomitride compound.
Det er beskrevet ovenfor en foretrukket utførelsesform for oppfinnelsen, men det er klart at man kan modifisere den uten at man derved kommer utenfor rammen for oppfinnelsen. Bornitridbelegget behøver ikke være tykkere enn en centimeter, men det kan være meget tykkere. For å oppnå en mekanisk binding kan bornitridet blan-des med digelmaterialet litt under borni-tridoverflaten, slik at digelen varierer fra en vesentlig ren bornitridoverflate til en blanding av bornitrid og digelmateriale, og deretter rent digelmateriale. Således kan f. eks. digelen bygges opp av et ytre lag av carbonholdig materiale, og et mellomlig-gende lag av blandet bornitrid og carbon og et indre lag av rent bornitrid. Etter bren-ning får den sammensatte struktur utmer-kede fysikalske egenskaper, som gjør den særlig egnet som understøttelse for fordampning av smeltet aluminium. A preferred embodiment of the invention has been described above, but it is clear that it can be modified without going beyond the scope of the invention. The boron nitride coating need not be thicker than one centimeter, but it can be much thicker. To achieve a mechanical bond, the boron nitride can be mixed with the crucible material slightly below the boron nitride surface, so that the crucible varies from a substantially pure boron nitride surface to a mixture of boron nitride and crucible material, and then pure crucible material. Thus, e.g. the crucible is built up of an outer layer of carbonaceous material, and an intermediate layer of mixed boron nitride and carbon and an inner layer of pure boron nitride. After firing, the composite structure acquires excellent physical properties, which make it particularly suitable as a support for evaporation of molten aluminium.
Understøttelsen for det smeltede aluminium kan opphetes ved motstandsopphetning, stråling og ledning, og også ved induksjon. En carbonstang som f. eks. er belagt med bornitrid kan elektrisk opphetes ved hjelp av sin egen motstand. The support for the molten aluminum can be heated by resistance heating, radiation and conduction, and also by induction. A carbon rod such as is coated with boron nitride can be electrically heated using its own resistance.
Claims (2)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB564272A GB1412772A (en) | 1972-02-07 | 1972-02-07 | Animal food |
Publications (2)
Publication Number | Publication Date |
---|---|
NO135396B true NO135396B (en) | 1976-12-27 |
NO135396C NO135396C (en) | 1977-04-05 |
Family
ID=9799925
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
NO437/73A NO135396C (en) | 1972-02-07 | 1973-02-02 |
Country Status (14)
Country | Link |
---|---|
JP (1) | JPS4890855A (en) |
AT (1) | AT327665B (en) |
BE (1) | BE794721A (en) |
CA (1) | CA1021985A (en) |
CH (1) | CH571828A5 (en) |
ES (1) | ES410920A1 (en) |
FR (1) | FR2171152B1 (en) |
GB (1) | GB1412772A (en) |
IE (1) | IE37101B1 (en) |
IT (1) | IT988587B (en) |
LU (1) | LU66963A1 (en) |
NL (1) | NL7301746A (en) |
NO (1) | NO135396C (en) |
SE (1) | SE405928B (en) |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5847139B2 (en) * | 1976-06-09 | 1983-10-20 | 日本農産工業株式会社 | Method for manufacturing pet food |
US4366175A (en) | 1978-07-25 | 1982-12-28 | Brown Bruce W | Glazed liver coated biscuit or kibble for pets |
US4229485A (en) | 1978-07-25 | 1980-10-21 | Jerky Treats, Inc. | Glazed liver coated biscuit or kibble for pets |
US4508741A (en) * | 1982-09-15 | 1985-04-02 | Star-Kist Foods, Inc. | Coated pet food and process for preparation thereof |
ES2051648B1 (en) * | 1992-12-11 | 1995-01-16 | Pablos Valverde Alejandro De | PROCEDURE FOR PREPARING AN EDIBLE PRODUCT FOR ANIMALS. |
JP4999107B2 (en) * | 2008-03-25 | 2012-08-15 | 日本製粉株式会社 | Method for producing food and pet food using roasted dried pasta |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1146926A (en) * | 1955-04-07 | 1957-11-18 | Unilever Nv | Flavoring substances and their manufacturing process |
US3467525A (en) * | 1964-12-14 | 1969-09-16 | Ralston Purina Co | Process for making an animal food |
IT1043796B (en) * | 1968-10-15 | 1980-02-29 | Ralston Purina Co | SUCCEDAMEO PRODUCT OF MEAT EXTRACT AND PROCEDURE FOR ITS PRODUCTION |
GB1285568A (en) * | 1969-03-25 | 1972-08-16 | Unilever Ltd | Edible products |
-
0
- BE BE794721D patent/BE794721A/en unknown
-
1972
- 1972-02-07 GB GB564272A patent/GB1412772A/en not_active Expired
-
1973
- 1973-01-12 IE IE47/73A patent/IE37101B1/en unknown
- 1973-01-17 CA CA161,497A patent/CA1021985A/en not_active Expired
- 1973-01-24 ES ES410920A patent/ES410920A1/en not_active Expired
- 1973-01-25 AT AT61473*#A patent/AT327665B/en not_active IP Right Cessation
- 1973-01-25 JP JP48009950A patent/JPS4890855A/ja active Pending
- 1973-01-26 IT IT19632/73A patent/IT988587B/en active
- 1973-02-02 NO NO437/73A patent/NO135396C/no unknown
- 1973-02-05 LU LU66963A patent/LU66963A1/xx unknown
- 1973-02-06 SE SE7301628A patent/SE405928B/en unknown
- 1973-02-06 FR FR7304055A patent/FR2171152B1/fr not_active Expired
- 1973-02-06 CH CH165573A patent/CH571828A5/xx not_active IP Right Cessation
- 1973-02-07 NL NL7301746A patent/NL7301746A/xx not_active Application Discontinuation
Also Published As
Publication number | Publication date |
---|---|
AU5187573A (en) | 1974-08-08 |
ATA61473A (en) | 1975-04-15 |
AT327665B (en) | 1976-02-10 |
IE37101L (en) | 1973-08-07 |
BE794721A (en) | 1973-05-16 |
CH571828A5 (en) | 1976-01-30 |
SE405928B (en) | 1979-01-15 |
FR2171152B1 (en) | 1976-11-05 |
IE37101B1 (en) | 1977-05-11 |
NO135396C (en) | 1977-04-05 |
IT988587B (en) | 1975-04-30 |
LU66963A1 (en) | 1973-05-15 |
FR2171152A1 (en) | 1973-09-21 |
DE2305968B2 (en) | 1977-04-21 |
JPS4890855A (en) | 1973-11-27 |
CA1021985A (en) | 1977-12-06 |
DE2305968A1 (en) | 1973-08-16 |
ES410920A1 (en) | 1976-04-16 |
NL7301746A (en) | 1973-08-09 |
GB1412772A (en) | 1975-11-05 |
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