JPH0746488B2 - Floppy disk liner and manufacturing method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a novel liner made of a fiber sheet used for lining a jacket for a floppy disc.

(Prior Art) A jacket for a floppy disc generally has a bag body made of a polymer resin sheet such as vinyl chloride resin or ABS resin, and a liner made of a fiber sheet is joined to the inner surface of the bag body. . The liner made of this fiber sheet is installed mainly for the purpose of cleaning the Floppy disk surface by blocking direct contact between the Floppy disk and the resin sheet constituting the main body of the jacket to avoid abrasion or damage on the surface of the Froppy disk. Therefore, various fiber sheets have been conventionally proposed. For example, Japanese Unexamined Patent Publication (Kokai) No. 58-7705 discloses a nonwoven fabric made of polyester fibers, and Japanese Unexamined Patent Publication No. 54-49115 discloses a nonwoven fabric made of polypropylene fibers.
No. 280 discloses a non-woven fabric made of recycled fibrous fibers.These methods include fusion of fibers to stabilize the form of the non-woven fabric, and bonding and fixing of fibers with an adhesive. It is used.

(Problems to be Solved by the Invention) On the other hand, when a general fiber sheet according to a known technique is used as a liner for a floppy disc, lint is generated due to the fall of adhesives, fibers, etc., and an error easily occurs. In particular, recently, the floppy discs have been largely changed to the direction of micronization, high density, and high speed rotation, and there is a strong demand for development of a high-performance liner for the floppy discs that can cope with this. Further, a liner for a floppy disc, which is produced by adhering and fixing fibers between them with an adhesive, produces less lint, but the cleaning effect is not sufficient and there is a problem as a liner for a floppy disc.

(Means for Solving the Problems) The present invention is a non-woven fabric including a thermoplastic fiber, having a thermocompression bonding portion and a non-thermocompression bonding portion, and having a fabric form maintained by the thermocompression bonding portion, and 1 to 10% by weight of the polymer resin is adhered to the floppy disk liner, and the sheet-like fiber assembly containing thermoplastic fibers is partially heat-pressed, and then the polymer resin 1 to This is a method for producing a liner for a floppy disk, which is characterized by adhering 10% by weight.

To explain the present invention in more detail, it includes a thermoplastic fiber,
Nonwoven fabrics having a thermocompression bonding portion and a non-compression bonding portion, and the structure of the fabric being retained by the thermocompression bonding portion, may be made of polyester, polypropylene, polyethylene, or thermoplastic fibers such as composite fibers thereof alone or the same. Obtained by blending fibers with different melting points even with thermoplastic fibers, or blending non-thermoplastic fibers such as rayon and cotton into a web shape with a card, random web bar, etc., and then heat-pressing with an embossing calendar etc. To be

The polymer resin is preferably a water-soluble or water-dispersible polymer resin, acrylic resin, urethane resin,
Examples include NBR resins, SBR resins, vinyl acetate resins, and the like. It is also possible to add a modifier such as a cross-linking agent or a leveling agent to these resins to improve the performance of the polymer resin. Even if a solvent-based resin is used, the effect obtained is not so different, but there are problems in cost, workability, safety, working environment, etc., which is not preferable.

The amount deposited is 10% by weight or less, preferably 1 to 10% by weight. If the adhered amount exceeds 10% by weight, the resulting liner becomes very hard, which damages the media of the floppy disc and has poor cleaning properties, and is not suitable as a liner for floppy discs.

As for the adhered state, it is preferable that the polymer resin is present more in the non-press-bonded portion than in the thermo-bonded portion. This is because lint is often generated from the non-pressure-bonded portion, and hardly generated from the pressure-bonded portion, and therefore the polymer resin needs to be attached to the non-pressure-bonded portion. Further, the adhesion of the polymer resin to the thermocompression bonding portion is not preferable because it has no effect on reducing lint and only hardens the liner.

The preferred physical properties of the liner of the present invention are: lint generation with a particle size of 10 μm or more, 80 particles / 10 cm ² or less, thickness compressibility of 32% or more, thickness recovery rate of 80% or more, and bending resistance of 0.6 gf.・ It is below cm. Among these, the thickness compressibility, the thickness recovery rate and the bending resistance are indicators showing the superiority or inferiority of the cleaning property of the liner, and the thickness compression rate is less than 32% or the thickness recovery rate is 80%. If it is less than 0.1% or the bending resistance exceeds 0.6 gf · cm, it indicates that the cleaning property is poor.

Here, the number of lint generated, the thickness compressibility, the thickness recovery rate, and the bending resistance are measured by the following methods.

[Number of lint occurrences]

Particles of the cleaning liquid after ultrasonic cleaning are measured under the following conditions using a liquid particle counter manufactured by Rion.

(A) Sample: 127 mm x 127 mm liner (b) Ultrasonic cleaner: Vuelvo Osoni (VS-70R) (c) Cleaning bath ratio: 1: 300 (pure water) (d) Cleaning time: 10 minutes [Thickness Compressibility] When the initial liner thickness is ² g / cm ^{2 and} the liner thickness is t _0, and the liner thickness is 40 g / cm ² is t ₁ , the liner thickness is calculated as follows.

(T ₀ −t ₁ ) / t ₀ × 100 (%) [Thickness recovery rate] The above 40 g / cm ² load is removed, and a load of 2 g / cm ² is applied, and the thickness after 1 minute is t ₂ Then, it is calculated from the following formula.

(T ₂ −t ₁ ) / (t ₀ −t ₁ ) × 100 (%) [Bending flexibility] JIS L-1096 Bending flexibility B method (slide method).

The liner for a floppy disc of the present invention has a structure in which a sheet-like fiber assembly containing a thermoplastic fiber is partially thermocompression-bonded to have a thermocompression-bonding portion and a non-pressure-bonding portion, and the thermocompression-bonding portion maintains a fabric form. It is manufactured by attaching a polymer resin to the non-woven fabric. To produce a non-woven fabric by a method in which a polymer resin is attached to a mere fibrous sheet-like material in which the cloth form is not kept by the pressure-bonding section, which is generally performed, in order to maintain the cloth form, a large amount of it is required. Since a non-woven fabric produced by this method requires a polymer resin, it becomes hard, the media of the floppy disc is damaged, and the cleaning property is poor. Therefore, it is not suitable as a liner for a floppy disc.

There are dipping method, coater, spray, etc. as a method for attaching the polymer resin to the non-woven fabric having a structure in which the polymer resin has a thermocompression-bonding portion and a non-pressure-bonding portion, and the fabric shape is maintained by the thermocompression-bonding portion. In any of the methods, it is important to nip with a mangle after attaching, so that the polymer resin is evenly attached not only to the surface of the non-crimped portion but also to the inside of the non-crimped portion, and Minimize the amount as much as possible and reduce the required amount of polymer resin as a whole as much as possible. Therefore, when it is used as a liner for a floppy disc, it has a remarkable effect in improving the cleaning property.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the cleaning property in Examples was measured by the following method.

[Cleaning method]

Using a Flotpie disk 2HD type, a polystyrene polymer (particle size: 3 μm) 5% dispersion liquid was added to the surface of the medium.
After dropping 1 ml and drying, a running test was performed for 1 minute with a floppy disc driver to visually judge the cleaning performance of the media surface liner after the test.

[Example 1] 50% by weight of polyester fiber (1.5d x 51mm) and 50% by weight of rayon fiber (1.5d x 51mm) were mixed and struck, and then a flat card was used to make a web, which was laminated 30g / m. Got ² webs. This is the pattern shown in Fig. 1, L = 1.2m
m, l = 1.0 mm, height 0.5 mm convex portion 1 is 25% of the roll surface
Occupying an embossing roll, with a flat bottom
It was thermocompression-bonded at a temperature of 180 ° C. and a pressure of 10 kg / cm to obtain a non-woven fabric having thermocompression-bonded portions and non-pressure-bonded portions. Nipol LX-
874 [Nippon Zeon Co., Ltd. acrylic resin emulsion] 1
After immersing in a solution of 00 g /, squeeze with a mangle so that the adhesion rate of the polymer resin solution is 100% by weight, and immediately at 150 ° C, 1
A drying process for 1 minute was performed. As a result, a liner for a floppy disc having 5% by weight of the polymer resin as a whole was obtained. In Comparative Example 1, the non-woven fabric having the above-mentioned thermo-compression bonding portion and non-compression bonding portion is not subjected to resin processing, and in Comparative Example 2 the resin is required as a liner for a floppy disc without a thermocompression bonding treatment using a calendar. A product was prepared so as to have a non-woven fabric strength. The amount of the polymer resin attached at this time was 15% by weight. The lint number (the lint number of 10 μm or more per 10 cm ² ) of the above liner, the cleaning property and the pass rate (%) in the dropout measurement were measured, and the results are shown in Table 1.

From the above results, it is understood that the liner for floppy discs obtained by the method of the present invention is a liner excellent in lint number and cleaning property as compared with Comparative Examples 1 and 2.

[Examples 2 to 6 and Comparative Examples 3 to 6] Rackstar 4700C [Dainippon Ink and Chemicals NBR resin emulsion] was added to the nonwoven fabric obtained in the same manner as in Example 1 and having a thermocompression bonding portion and a non-thermocompression bonding portion. The liner to which the amount of adhesion was changed variously was obtained. The lint number, cleaning property and dropout pass rate of the obtained liner are second.
The results are shown in the table (next page).

50% of low melting point polyester fiber (4d * 51mm) of melting point 130 degrees Celsius
50% polyester fiber (1.5d × 51mm) with melting point of 255 ℃ and 50% rayon fiber (1.5d × 51mm) on both sides of a mixed web (70μ thick) consisting of 50% rayon fiber (1.5d × 51mm)
% And mixed webs (thickness 70 μm each) are laminated in the shape of Saint-Gerchi and partially thermocompressed at a temperature of 180 ° C. and a pressure of 10 kg / cm, and then Nipol LX-874 [Nippon Zeon Co., Ltd.].
Made of acrylic resin emulsion] 100g / solution, squeezed with a mangle so that the polymer resin becomes 100% by weight, and immediately after immersing it with a mangle so that the polymer resin becomes 100% by weight Immediately, it was dried at 150 ° C. for 1 minute to obtain a liner having a polymer resin content of 5% by weight.

The performance of the obtained liner was as follows.

Lint number 14 Compression rate 33.4% Recovery rate 96.7% Bending softness 0.21gf · cm Very good cleanability Dropout pass rate 100% (Effect of the invention) The Flotpie disk liner of the present invention constructed as described above is a Flotpie The amount of lint that causes the disk error is extremely small, and the cleaning property required as a liner for floppy disk is good.
It is extremely useful as a high-performance liner for floppy discs, which is compatible with the recent microminiaturization, high density, and high speed rotation of floppy discs.

[Brief description of drawings]

FIG. 1 shows the embossing pattern of the embossing roll used in the examples. 1 ... convex

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuu Makihara 4-1-60 Sanada Rayon Co., Ltd., Higashi-ku, Nagoya, Aichi Prefecture (72) Inventor Masanori Ito 4-1-60 Sanadabashi, Higashi-ku, Nagoya, Aichi Prefecture Ryo Rayon Co., Ltd. In-house referee body Chief referee Yasuo Hori Referee Jumiko Niki Referee Hiroyuki Oguro (56) Reference JP-A-60-127580 (JP, A) JP-A-59-60776 (JP, A) JP JP-A-60-83281 (JP, A) JP-A-53-103714 (JP, A) JP-A-60-187981 (JP, A) JP-A-60-1009076 (JP, A) Actual development JP-A-57-177277 (JP , U) Actually developed 60-120568 (JP, U)

Claims (2)

[Claims] 1. A non-woven fabric containing thermoplastic fibers, having a thermocompression-bonding portion and a non-thermocompression-bonding portion, and having a fabric shape maintained by the thermocompression-bonding portion, and containing 1 to 10% by weight of a polymer resin. A liner for a floppy disk characterized by being attached. 2. A process for producing a liner for a floppy disk, characterized in that a sheet-shaped fiber assembly containing a thermoplastic fiber is partially heated and pressure-bonded and then a polymer resin is adhered thereto in an amount of 1 to 10% by weight.