JPS5929268B2 - Fiber batt and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fiber batt (wadding) and a method for producing the same.

Heretofore, complete drying methods for forming fiber batts are known and are known, for example, in U.S. Pat.
No. 765971.

However, prior methods such as Fleissner's method,
It has many drawbacks. First of all, it has been difficult or impossible to homogeneously mix the particulate binder with the fibers to be bound. This inability to achieve uniform mixing causes the formation of butts with non-uniform strength. Second, previous efforts to use practical dry adhesives have been unsuccessful. SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved method for producing fiber batts which substantially eliminates the disadvantages of the prior art.

Another object of the invention is to provide an improved method of manufacturing batts of uniform strength.

Yet another object of the invention is to provide an improved process using particularly advantageous binders.

Yet another object of the invention is to provide an improved fiber batt.

Still another object of the present invention is to provide improved manufacturing equipment useful in the manufacture of such batts.

The above and other objects include the process of lying down: forming a thin web of fibers; contacting the web with an adhesive mass of granular vinyl chloride and vinylidene chloride copolymer; forming a butt with said web. and heating the batt above the softening point of the copolymer and at a temperature below the degradation point of the fibers.

The reason for this will be explained in more detail below. Thin webs are generally made of 1 to 200 fibers.
thickness (fiber thickness), preferably 1 to 100 fiber thickness. In the broadest aspect of the invention, any fiber can be used to make the thin web. The invention is particularly applicable to fibers that have resistance to cigarette fire, especially low residue and/or low cigarette resistance fibers. Fibers include natural animal and plant fibers such as wool, flax and cotton; acrylic fibers;
Examples include, but are not limited to, synthetic fibers such as polyolefin fibers, polyamide fibers such as nylon, and polyester fibers such as polyethylene terephthalate. The fibers are (a) cotton only, (b) other fibers in general,
Particular advantages according to the invention are achieved when cotton is mixed, especially with thermoplastic fibers and especially with polyester fibers, and only with c-polyester fibers. Batts formed from a blend of cotton and polyester fibers contain from 5 to 95 percent by weight, preferably from 50 to 80 percent by weight, of cotton based on the total weight of the fibers. The polyester/cotton blend has improved fastness and cigarette resistance over all cotton batts. As the content of polyester fiber increases, the butt becomes more rigid:
Furthermore, comparable cigarette resistance can be obtained with lower copolymer contents. Generally the copolymer has a weight ratio of vinyl chloride to vinylidene chloride of 1:99 to 40:60, and preferably of 5:95 to 25:75.

At high proportions, the copolymer exhibits properties that are indistinguishable from those obtained when homopolymers of vinyl chloride are used. Similarly, at low proportions, the use of copolymers does not exhibit any advantages not obtained by using pure vinylidene chloride. The copolymer is applied to the web in an amount sufficient for its function as an adhesive, generally in a weight ratio of copolymer to fiber of 1:99 to 30:70 and preferably 10:90 to 20:80. The copolymer particles generally have a particle size of 1 to 200 microns, preferably 5 to 50 microns. Smaller particle sizes are industrially useful but expensive to manufacture. Larger particle size not only unnecessarily increases the weight of the resulting batt, but also reduces the number of crosslinks that can occur in a given weight of fiber, weakening bonding capacity and strength. Copolymers useful in this invention have a stick point of 300 to 700'F.

All copolymers of vinyl chloride and vinylidene chloride useful in this invention have this property, or have been prepared to obtain this property according to techniques well known in the art which do not form part of this invention. It may be degenerated into. For this modification, other monomers such as vinyl acetate may be present in the polymerization chain, or other polymers may be added. One copolymer useful for use in the present invention is manufactured by Tau Chemical Co. (Mislant, Mich.) under the trade name: SaranResin XP-523.
0.04, Saran Resin
P-2384.49, Saran Resin
sin)XP-4174.19, Saran Resin (Sa
ranResin) XP-5230.05, Saran Resin (SaranResin) XP-5230.06,
and Saran Resin XP-
It is a product of 5230.08. As used herein, the term "polyester" refers to a polymer having reverse ester bonds in its main chain and having the ability to form high molecular weight fibers.

A preferred polyester is polyethylene terephthalate, a method of making which is disclosed in U.S. Pat. No. 2,465,319 to Winfield et al. After applying the copolymer to the wafer, the wafer is molded into a butt. It is not feasible to apply copolymers to preformed batts. This is because it is difficult or impossible to ensure penetration of the particles into the butt. As used herein, batt refers to the majority web collection b. The vat formed as described above is heated to a temperature above the grain deposition point of the copolymer and below the fiber decomposition point.

The temperature is generally from 300 to 400'F, preferably from 325 to 375'F. At very low temperatures, the copolymer will not melt, while at very high temperatures, the fibers will be attacked. Heating is carried out for a sufficient time to effect melting of the copolymer. Generally the melting period is from 1 to 20 minutes, preferably from 2 to 10 minutes.
Happens within minutes. The present invention will be described below with reference to the drawings, particularly FIG.

The drawings show a main body of a bat manufacturing apparatus and an associated furnace provided by the present invention.

The apparatus main body 10 includes an opener or garnet 11, a particle supply body 12, a cross-reining mechanism 13, and a second
It consists of a furnace 14 as shown in the figure. Garnet 1
1 includes an inlet chute 8 adapted to fit into a rotating drum 19 of garnet 11 for supplying loose fibers. Garnet 11 also has a large number of gear rolls 2.
1, 22, 23, 24, 25 and the rolls carry loose fibers 20 with teeth not shown on the drum 19, which are formed into a web and adhered to the drum 19. The web adhering to drum 19 is transferred to drum 28 where it is removed by comb 29. The web 31 located only between the 1 and 100 fiber wicks is a barely self-supporting dripping body for the conveyor 32 passing under the particle supply body 12. While supported thereby, the web 31 comes into contact with particles 33, 34 falling from the particle supply 12 under the influence of gravity. web 3
1 is supported on the conveyor 32, so that the particles 3
3, 34 do not pass through the web 31, but rather are retained by it. In order to further ensure the shape of the web 31 having particles 33, 34, the web 31 is rolled by two rotating rolls 36,
3r, while the lower roll 3r performs the dual function of providing support for the conveyor 32. The web 39 then transfers to a conveyor 41 and then to a conveyor 42. As is well known in the industry, the lower end of the conveyor 42 is attached to a traveler 43 which moves back and forth on a track 44. Conveyor 42 is located above and at right angles to conveyor 45. The device is adjusted such that the speed of conveyor 42 is several times faster than the speed of conveyor 45. With this arrangement,
The web 39 is orthogonally placed back and forth on the conveyor 45,
An unheated vat 4r is formed. Unheated butt 4
7 is the upper Foraminous belt (FOraminou)
sbeit) 47 and the lower fluoraminous belt 50 (
(see Figure 3). The unheated vat 4r passes through the furnace 14 while being held between the belts 49 and 50. As shown in FIG.
Heating means 52 are provided which can be thermostatically controlled by. Although the furnace 14 is not shown, the arrow 5
5 and 56 are provided with air circulation means for circulating air in the direction of the arrow. The final molded product is a heat-treated batt 58. The present invention will be further explained below with reference to Examples, but the present invention is of course not limited thereto.

It should be noted that all parts and percentages are by weight unless otherwise stated. Example 1 Name XP-5230.04 manufactured by DOW Chemical Co., Mitsudranondo, Michigan.
A copolymer of vinyl chloride and vinylidene chloride is added to the cotton web in the manner described above according to the drawings.

That is, a cotton web 31 is formed, then the thin web is passed under the particle supply body 12, and one particle of a copolymer of vinyl chloride and vinylidene chloride is caused to fall onto the web 31 under the influence of gravity. The web 31 was then shrunk by the cross-reining mechanism 31, and the batt was heated in a furnace 14 above the adhesive point of the copolymer and below the temperature at which the fibers would burn, to obtain the fiber batt of the present invention. It should be noted that the copolymer used in this Example 1 had a weight ratio of vinyl chloride to vinylidene chloride of 10:90, a chlorine content of 71%: plasticizer: 1%, a minimum particle size of 40 microns and a
It has a maximum particle size of 0 microns. Examples 2-6 The procedure of Example 1 was repeated using the copolymer shown in column 2 of the table in place of copolymer 1 used in Example 1 to obtain fiber batts.

Examples 7 to 12 Similar polyester fiber batts were obtained by reversing the procedure of Examples 1 to 5 using a polyester web of polyethylene terephthalate instead of the cotton web used in Examples 1 to 6. .

Examples 13 to 18 As a substitute for the cotton web used in Examples 1 to 6,
V, cotton-polyester fiber batts were obtained by reversing the procedures of Examples 1 to 6 using 50% by weight cotton-fiber-equivalent polyethylene terephthalate fibers.

Although the present invention has been described in considerable detail by means of several preferred embodiments, modifications and improvements can be made to the spirit of the invention as set forth above and as made clear by the claims. It will be understood that the invention may be implemented within a range.

[Brief explanation of drawings]

FIG. 1 is a front view of a preferred apparatus for carrying out the method of the present invention, FIG. 2 is a plan view of the apparatus, and FIG.
-3 sectional view. 10...Device body, 14...Furnace, 20...Loose fibers, 33...? child, 34...particle.

Claims (1)

[Claims] 1 Step I of forming a thin web of fibers; Step II of contacting the web with a granular polymer; Step III of forming the web into a batt; and step IV of heating below the decomposition point of the fibers. 2. The method for manufacturing a fiber batt according to claim 1, characterized in that cotton is used as the fiber. 3. The method for manufacturing a fiber batt according to claim 1, characterized in that polyester fibers are used as the fibers. 4. The method for manufacturing a fiber batt according to claim 1, wherein the web has a thickness of 1 to 100 fibers. 5. The method for producing a fiber batt according to claim 1, wherein the polymer is a copolymer of vinyl chloride and vinylidene chloride. 6 The weight ratio of vinyl chloride to vinylidene chloride is 1:
8. The method for producing a fiber batt according to claim 7, wherein the ratio is 99 to 40:60. 7. Claim 1, characterized in that the weight ratio of copolymer to fiber is from 1:99 to 30:70.
The method for manufacturing the fiber batt described in Section 1. 8. A method for producing a fiber batt according to claim 1, characterized in that the particles of the copolymer have a particle size of 1 to 200 microns. 9. A method of making a fiber batt according to claim 1, wherein the copolymer has a tack point of 300 to 370 degrees Fahrenheit. 10. The method of claim 1, wherein the temperature in step IV is in the range of 300 to 400 degrees Fahrenheit. 11. The method for producing a fiber batt according to claim 1, wherein the heating is carried out for a period of 1 to 20 minutes. 12 forming a horizontally arranged thin planar fibrous web, said web having a thickness of 1 to 100 fibers, while the web is in contact with and supported by a moving belt; Step II of contacting the web with particles of vinyl chloride and vinylidene chloride, although the belt prevents the passage of the copolymer into the web; during step II, the weight ratio of vinyl chloride to vinylidene chloride is 5:95. or 25:75 and A
B, the copolymer to fiber weight ratio is from 10:90 to 20:80; C, the particles of the copolymer have a particle size of 5 microns to 50 microns; and D, the copolymer has a stick point of 300 to 700°F. ], step III of passing the web and adhesive particles between the nip of two rotating rolls to force the particles into the web, and passing the web laterally on a moving belt so that the vat contains a large number of webs. Step IV of forming the web into a batt by placing it back and forth, passing the batt between two parallel firm belts in the furnace, and during this time blowing hot air between the belts and the batt to melt the copolymer particles. fibers having high compressive strength, including sequentially heating the batt for 2 to 10 minutes at a temperature of 325°F to 375°F, and cooling the batt with room temperature air to resolidify the copolymer. The method for manufacturing a fiber batt according to claim 1, which is a completely dry method for manufacturing a batt. 13. A fiber batt characterized in that each fiber is bonded at the fiber intersections by melting and resolidifying particles of a copolymer of vinyl chloride and vinylidene chloride. 14. The fiber batt according to claim 13, wherein the fiber is cotton. 15. The fiber batt according to claim 13, wherein the fiber is polyester.