Classifications

• • D—TEXTILES; PAPER
  • D02—YARNS; MECHANICAL FINISHING OF YARNS OR ROPES; WARPING OR BEAMING
  • D02G—CRIMPING OR CURLING FIBRES, FILAMENTS, THREADS, OR YARNS; YARNS OR THREADS
  • D02G3/00—Yarns or threads, e.g. fancy yarns; Processes or apparatus for the production thereof, not otherwise provided for
  • D02G3/02—Yarns or threads characterised by the material or by the materials from which they are made
  • D02G3/16—Yarns or threads made from mineral substances
  • D02G3/18—Yarns or threads made from mineral substances from glass or the like
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
  • C03C25/00—Surface treatment of fibres or filaments made from glass, minerals or slags
  • C03C25/002—Thermal treatment
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06B—TREATING TEXTILE MATERIALS USING LIQUIDS, GASES OR VAPOURS
  • D06B3/00—Passing of textile materials through liquids, gases or vapours to effect treatment, e.g. washing, dyeing, bleaching, sizing, impregnating
  • D06B3/10—Passing of textile materials through liquids, gases or vapours to effect treatment, e.g. washing, dyeing, bleaching, sizing, impregnating of fabrics
• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06B—TREATING TEXTILE MATERIALS USING LIQUIDS, GASES OR VAPOURS
  • D06B2700/00—Treating of textile materials, e.g. bleaching, dyeing, mercerising, impregnating, washing; Fulling of fabrics
  • D06B2700/09—Apparatus for passing open width fabrics through bleaching, washing or dyeing liquid

Definitions

• This invention relates to a process for removing size or binder material from an unfinished glass fabric, and particularly to a continuous process for thermally desizing such a fabric.
• Glass fabrics as the term is employed herein, refers to fabrics knitted, netted or woven in a definite pattern from yarns made up of a number of filaments of glass, as distinguished from a random distribution of filaments as in glass wool.
• a sizing material which serves as a continuous filament binder and affords a measure of protection to the filaments during weaving or knitting or subsequent textile treatments.
• the sizing material lubricates the glass filaments and the strands or yarns produced therefrom and allows them to slip over one another without undue abrasion and resulting breakage.
• the size is usually organic in nature, for example consisting of starch or dextrinized starch, gelatine, a complex amine, and in most instances a lubricant such as mineral, animal or vegetable oil.
• the size, or binder material as it is sometimes called,
• the fabric, particularly industrial fabric be desized in a manner which reduces the original strength of the greige goods as little as possible.
• the desized fabric should be as light in color as possible, preferably exceedingly white. It is entirely possible for two identical desized fabrics to have the same ignition loss and yet one may be a light tan and the other an excellent white as a result of different desizing techniques.
• the Whiter fabric is preferred for both decorative and industrial purposes.
• the glass fabric is rolled up on perforated mandrels and the resulting large rolls are placed in an oven which is maintained at between about 500 and 700 F., and the size is slowly volatilized from the fabric.
• the total time in the oven ranges between about 55 and 80 hours. While the batch oven technique thus consumes a very appreciable amount of time, the desized fabric is white and has an ignition loss of about 0.1%, which is considered quitesatisfactory.
• the tensile strength of the fabric is reduced by about 50%, which is somewhat below the strength reduction desired for industrial purposes.
• the other low temperature technique is a continuous treatment at temperatures sufficiently low to prevent burning of the size at the surface of the fabric.
• Coronizing Continuous high temperature desizing is referred to in the art as Coronizing.
• the glass fabric to be desized is passed in open width through a vertically or horizontally disposed furnace and subjected;
• a second high temperature desizing process is described, in Merrill R. May US. Patent No. 2,970,934, dated February 7, 1961. According to that process a length of the fabric in open width is continuously passed through a furnace or thermal treating zone which ismaintained at a substantially lower temperature, namely between about 900 and 1050" F. This lower temperature is sufficient to cause ignition and burning of the size on the surfaceof the fabric, but the process differs from that of Klug-and Waggoner in control of the atmosphere within the treating zone so that burning occurs at a point just inside the exit or discharge opening of the furnace, and such burning is with a yellow flame, as distinguished from the much hotter blue flame.
• the May process also produces a de-, sized glass fabric with an ignition loss of about 0.1%, but the tensile strength of the desized fabric is between about 70 and of that of the greige goods.
• Thedesized fabric is a light amber or off white material.
• Style 802 a light weight leno weave weighing only 2.03 oz./ sq. yd., substantiated the above observations that once the size is properly removed, the elevated temperature can be sustained for additional periods without significantly decreasing the physical properties of the goods.
• Style 802 was exposed in a pilot furnace having three temperature zones maintained at 1100, 1260 and 1400 F. for a total of about 7.5 seconds. Subsequent runs were at exposure times of 12 and 1.5 seconds. Unfinished Mullen strengths were 34, 33 and 31 lbs/sq. in;, respectively.
• the vertical pilot unit was modified to provide three two-foot sections or zones which were maintained at progressively higher temperatures.
• the fabric was introduced at the top of the furnace in which the first zone was maintained not above about 1100 F., the second or middle zone at between about 1100 F. and about 1280 F. and the third or bottom zone at a temperature above 1280 and up to 1350 F.
• the first zone was maintained not above about 1100 F.
• the second or middle zone at between about 1100 F. and about 1280 F.
• the third or bottom zone at a temperature above 1280 and up to 1350 F.
• the fabric is continuously introduced into a first zone maintained'at a temperature sufficiently high to fairly rapidly volatilize the size, preferably above 800 F. but not above about 1100 F.
• the volatilized size is so diffused, preferably with air, that burning which is possible at temperatures between about 800 and 1100 F. is avoided, and then the fabric is introduced into another zone where it is raised to proper weave setting temperatures, i.e. up to about 1400 F. and the remaining size is volatilized, but not permitted to burn adjacent the fabric in this other zone.
• proper weave setting temperatures i.e. up to about 1400 F.
• the remaining size is volatilized, but not permitted to burn adjacent the fabric in this other zone.
• it is possible to carry out the present process by first heating the fabric up to about 1100 F. and then subjecting it to temperatures between about 1280 and 1400 F. in a second zone, for example, it is preferred to employ one or more intermediate zones serving to gradually raise the temperature of the fabric to the range 1280-1400 F., thus avoiding
• Style 978 a heavy boucl fabric weighing 9.22 ounces per square yard and having an initial ignition loss of 1.91%, unless the ignition loss is reduced to about 0.20% or below during initial heating, a very white product is not obtained.
• the ignition loss of about 2.4% is preferably reduced to about 0.15% in the first zone.
• Burning of the size is avoided in the first zone by sodiifusing the volatilized size as to produce a mixture of size vapor and air too lean to ignite and burn.
• This diffusion may be most simply effected by providing an adequate draft through at least the first or fabric entering zone of the furnace, A major portion of the diffused volatilized size is desirably removed from the vicinity of the fabric in the first zone, so that only a minor portion of the vapor produced therein may enter the second and any subsequent zones of the furnace. Where the furnace is vertically disposed with the coolest zone at the top and the fabric is passing downward the problem of diffused vapors entering the second or subsequent hotter zones of the furnace does not exist.
• the Smith furnace provides a muffie run comprising at least three heat treating zones, each of which are provided with vapor exhausting means.
• the novel desizing process of this invention has thus far been described as the sequential heating of a glass fabric in two or three stages or thermal treating zones, the process may be carried out in a muffle furnace comprising but a single zone maintained at incrementally increased temperatures over its entire length, it being essential only that the fabric be subjected to gradually increasing temperatures and that a major portion of the size be removed below about 1100 F.
• a muffle furnace comprising but a single zone maintained at incrementally increased temperatures over its entire length, it being essential only that the fabric be subjected to gradually increasing temperatures and that a major portion of the size be removed below about 1100 F.
• the base ofthe furnace might be maintained at 900 F., but a foot or two above the base the temperature of the muffle may be 1000 F. and so on to the exit end of the muffie which might be maintained at 1400 F.
• auxiliary means such as a fan need be provided for avoiding ignition in the second or third treating zones, although in some instances it may be desirable to provide an independent draft in the zone subsequent to the initial heating zone to prevent ignition therein.
• a major portion of the diffused size vapor is removed from the mufiie at the head of the first zone so that the draft to the second zone plus the size vaporized therein does not produce an ignitible mixture in the second zone.
• the second zone provides a very gradual transition to the temperatures above about 1280" F. necessary to effect proper weave setting and fiber relaxation, which impart a desirable feel and hand to the desized fabric.
• the size remaining on the fabric is substantially completely volatilized and the desized fabric has an ignition loss between about 0.02 and 0.08%.
• the desized fabric is exceedingly white.
• the first zone maintained at temperatures up to about 1100 F. results in a substantially lower rate of volatilization of the size than occurs in conventional Coronizing process, a rate sufiiciently low that combustion does not take place with a normal air draft which would support combustion at higher temperatures.
• a forced draft in the first or fabric entering zone to avoid ignition and combustion of the size therein.
• Table II reports tests conducted with heavier fabrics, namely boucl Styles 95919 and 978.
• Table III reports the results of tests carried out with a heavy industrial glass fabric, and Table IV the rate of volatilization from that fabric.
• Table 111 [Industrial fabric HG639.76 oz./sq. yd. Thickness 0.14 in. Warp and fill: 16 X l il50S 4/2] Tensile Temp Dwell Ignition Run F.) Time loss Unfinished Volan Color (See) (Percent) Warp Fill Warp Fill Greige Goods 2.2 308 279 1,020 7 1 1,280 7 1,350 7 0.06 130 I18 Grey White. 1,020 10 i 2 1, 280 10 1, 350 10 0. 05 103 199 128 Good White. 1,020 15 a 1,280 15 1,350 15 0. 03 79 73 I55 131 Excellent White.
• a proper time sequence for a fabric such as PIG-63 is approximately 4 seconds at 1200 F., 8 seconds at 1250" F. and about 15 seconds at 1300 F.
• a vertical furnace is preferred to a horizontally disposed muffie since with the former it is possible to have a much longer thermal treating run without imposing undue tensile stress upon the hot fabric or encountering sagging as in a horizontal furnace.
• desizing is carried out without a flame and under initial heating conditions, preferably between 800 and 1100 F. such that a major portion of the size, preferably between 75 and about 95%, is volatilized from the fabric and so diffused as to prevent ignition of the same.
• the fabric is then gradually raised into the range of about 1280-1400 F. for substantially complete volatilization of the size and setting of the weave.
• a process for desizing a sized unfinished glass fabric which comprises heating an advancing length of said fabric to a temperature sufficiently high to volatilize the size from the fabric, maintaining the fabric at such temperature for a time sufficient to volatilize at least 75% of the size, so diffusing the volatilized size as to prevent ignition and burning of the same adjacent the fabric, raising the temperature of the partly desized fabric to a temperature sufliciently high to set the fibers thereof, and volatilizing substantially all of the remaining size from the fabric while diffusing the volatilized size to prevent ignition and burning of the same in the vicinity of the fabric at the elevated temperature.
• a process for desizing a sized unfinished glass fabric which comprises heating an advancinglength of said fabric to a temperature sufficiently high to volatilize the size from the fabric, maintaining the fabric at such temperature for a time sufficient to volatilize at least 75% of the size, so diffusing the volatilized size as to prevent ignition and burning of the same adjacent the fabric, removing volatilized size from the vicinity of the fabric, raising the temperature of the partly desized fabric above about 1100 F. to set the fibers thereof, and volatilizing substantially all of the remaining size from the fabric, while diffusing the volatilized size to prevent ignition and burning of the same adjacent the fabric during-raising of the temperature and while the fabric is at fiber setting temperature.
• a process for desizing a sized unfinished glass fabric which comprises gradually heating an advancing length of said fabric to a temperature sufficiently high to vo1a tilize the size from the fabric up to about 1100 F., maintaining the fabric at such temperature for a time sufficient to volatilize a major portion of the size, so diffusing the volatilized size as to prevent ignition and burning of the same adjacent the fabric, removing volatilized size from the vicinity of the fabric, gradually raising the temperature of the partly desized fabric sufiiciently to set the fibers thereof and not above about 1400 F., and volatilizing substantially all of the remaining size from the fabric, while diffusing the volatilized size to prevent ignition and burning of the same adjacent the fabric during raising of the temperature and while the fabric is at fiber setting temperature.
• a process for desizing a sized unfinished glass fabric which comprises heating an advancing length of said fabric to a temperature between about 800 F. and 1100 F., maintaining the fabric at such temperature for a time sufficient to volatilize between about and of the size, so diffusing the volatilized size as to prevent ignition and burning of the same adjacent the fabric, gradually raising the temperature of the partly desized fabric to between about 1280 F. and 1400 F., and volatilizing substantially all of the remaining size from the fabric, while diffusing the volatilized size to prevent ignition and burning of the same adjacent the fabric during said gradual temperature raising and while the fabric is at said latter temperature.
• a process for desizing a sized unfinished glass fabric which comprises continuously introducing an advancing length of said fabric to a treating zone maintained at a temperature between about 800 F. and 1100 F., retaining the fabric in said zone for a time suflicient to volatilize a major portion of the size, so diffusing the volatilized size as to prevent ignition and burning of the same adjacent the advancing fabric, exhausting a major portion of the volatilized size from said zone, subsequently introducing the advancing partially desized fabric to another zone maintained at a temperature between about 1280 F.
• a process for desizing a sized unfinished glass fabric which comprises continuously introducing an advancing length of said fabric to a treating zone maintained at a temperature between about 800 F. and 1100 F., retaining the fabric in said zone for a time sufficient to volatilize a major portion of the size, so diffusing the volatilized size in said zone as to prevent ignition and burning of the same therein, exhausing a major portion of the volatilized size from said zone, introducing the advancing partially desized fabric to a zone maintained at a temperature between about 1100 F.

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• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Textile Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Thermal Sciences (AREA)
• General Life Sciences & Earth Sciences (AREA)
• Physics & Mathematics (AREA)
• Mechanical Engineering (AREA)
• General Chemical & Material Sciences (AREA)
• Geochemistry & Mineralogy (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Woven Fabrics (AREA)
• Treatment Of Fiber Materials (AREA)
• Nonwoven Fabrics (AREA)
• Treatments For Attaching Organic Compounds To Fibrous Goods (AREA)

Priority Applications (5)

Applications Claiming Priority (1)

Publications (1)

Family

ID=21981507

Family Applications (1)

Country Status (5)

Cited By (8)

Citations (1)

• 1960
  • 1960-08-31 US US53034A patent/US3012845A/en not_active Expired - Lifetime
• 1961
  • 1961-07-26 GB GB27008/61A patent/GB921650A/en not_active Expired
  • 1961-08-22 CH CH979261A patent/CH372022A/fr unknown
  • 1961-08-29 DE DE19611410893 patent/DE1410893A1/de active Pending
  • 1961-08-30 BE BE607689A patent/BE607689A/fr unknown

Patent Citations (1)

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