DE1990727U - Abrasive fabric sheet made from regenerated cellulose fiber sheet - Google Patents

Description

Patent attorney. Hfl K J f] \ QQ * *) LASS CS. j _Dfi

2 Hamburg 70. . '' Stfe 'Al ¹ I ⁰ obm * 02 «OCT. W.

Sdiloßstraße 11Z Postfadi 10914

Telephone: 652 97 07 '

Applicant :. REICHHOLD CHEMIE AKTIENGESELLSCHAFT Hamburg 7O ₃ Iversstr «57

Inventor: Hermann Singer and Dietmar Wunderlich both in Hamburg

Abrasive fabric sheet made from regenerated cellulose fiber sheet

_S found to be primarily for the production of high quality abrasive cloth, the rich in the form of abrasive belts for machine sanding in the metal and wood processing industry Uses: cotton fabric. As a fabric construction, for example, a twill fabric (2: 1) with a thread count per cm of 3 ^ / '2O.5 made of cotton yarns of thicknesses 20/28 m / gj, the fabric weight of the desized

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Fabric is approx. 235 g / m. * Such a fabric has in the warp direction a breaking load of about 23 kgf / cm with an ultimate elongation of IJ% to _s whereas the corresponding tear resistance Swerte for the weft direction at a breaking load of 10 kgf / cm and an ultimate elongation of 8% are. (Tensile test on strips of text lien sheets according to DIN 53-8.57 · The result obtained was 5 divided ₃ to of the 5 cm wide test on 1 cm converted.) Since abrasive cloth formulated as abrasive belts in their use direction, which is the warp or longitudinal direction of the fabric _{9 may} only have a very low extensibility _s because otherwise there is a risk that the grinding belts, under the influence of the tensile stress occurring during the grinding process, become excessively long and run off the contact disk of the grinding machine ₃ it is necessary _s that-

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like fabrics during the finishing process in the wet condition to subject a stretching process, the through Finishing agent storage is fixed after the fabric has dried. An equipped abrasive backing fabric on the base of the above-mentioned cotton fabric type has e.g. B. the following properties: (for comparison is still in the right column the corresponding raw fabric is listed once).

weight ;. Equipped
tissue g / m Raw fabric
(desized) g / m ² Middle Areas ^ Warp Λ ■ - ■ 315 kp / cm 236 kp / cm Tear strength in
direction /■"■.■ "40- , 5 fo 23 % Elongation at break 6, , 6 kp / cm 17th kp / cm Tear strength in
Weft direction 10

Elongation at break. 20 % 8 %

It is seen that the originally present in the warp direction opposite to the direction of firing greater elongation during Zerreißvorganges by the stretching and apprêt-urvorgang was significantly reduced ,, ..while the elongation is significantly increased in the weft direction - in other words, it was the The stretching and finishing process partially relocates the existing stretch in the warp direction in the weft direction. A fiber material based on cotton has the ideal prerequisites for stretching it when wet _: state in the warp direction, strong forward. In the case of cotton fibers or fabrics, the elongation increases at the beginning of the tearing process, even with a small force. very too, only to hardly increase with further tensile stress, ie it is

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possible, cotton fibers, and accordingly also cotton fabrics to be given a largely low-stretch finish in the warp direction by means of a wet stretching process.

Disadvantageous for the use of abrasive raw fabrics on the The basis of cotton is that it is relatively complicated prepared dry and wet finishing process must be subjected before they are equipped in the actual sense, That is, they can be finished. The reason for this is that one for the manufacture of abrasive fabrics highly absorbent carrier fabric is required, as only these meet the requirements for perfect adhesion of the finishing agents and binders to the fabric.

But cotton contains wax and growth accompanying substances fatty nature, which cause a significant disruption of the wettability and absorbency of the tissue and only through intensive, costly finishing pretreatments, such as desizing, alkaline decoction and cupping - in each case in Connection with numerous flushing processes - can be removed. . - - \ -. .

There has been no lack of attempts to create abrasive fabrics made from cellulose i.e. based on regenerated cellulose, to manufacture. As far as it is low-quality abrasive cloth sheets for manual grinding processes, this has already been practiced with success for years. But it is so far noch.not flawlessly succeeded, cellulose tissue for high quality Abrasive grain backing fabric webs that are suitable for the production of abrasive fabric tapes: for machine sanding, . : '■■ "■■. ■■■■ /', ■■:... - ■ \; ■■ - 4 -

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to use. This is related to the fact that conventional viscose wool fabrics have a greatly reduced wet strength compared to cotton fabrics compared to the corresponding strength values in the dry state. Perner, its swelling value - better water retention capacity - is significantly higher than that of cotton fibers. Des'weiteren is known that viscose fiber type en largely proportionality between force and elongation occurring is \ therefore it is not möglieh while the ITaß equipment- dehnungsarm.zu fix the viscose fabric by mechanical stretching.

The latest developments in the field of pulp fibers but have led to solid cell materials that can be found in their Both dry and wet tear behavior are very close to that of cotton. You can even find that the dry strength such cellular wool materials is significantly higher than that of cotton, while their elongation behavior during the tearing process in both dry and wet condition largely corresponds to that of Baumwo 11 fibers. At this stage of development of cellulose fibers are fibers made from regenerated cellulose, especially from the Polynosic-G group, which a certain term within cellulose technology represents, (To prevent .that all possible types of pasers from regenerated cellulose are called polynosic, the Association International Polynosic (AIP) has drawn up certain technical requirements that polynosial lasers met: must be.)

It would be of general advantage in the manufacture of abrasive cloth Cellulose fabric made from regenerated cellulose, in particular

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of the Polynosic Group, to be used as abrasive roll fabric, there these because of their natural. Cleanliness much less complicated with the letting equipment. are to be treated as normal Cotton fabric. - ...

The disadvantage is that the conventionally sized warp thread Abrasive backing fabric, due to the conventional sizing, anti-adhesive; character compared to the later have conventional finishing binders to be applied and therefore have to be desized in a conventional manner. In addition, abrasive backing fabrics have been made from regenerated Cellulose, especially from the Polynosic group, in comparison a much greater absorbency than loosened cotton fabrics and therefore use a lot more finishing agent on, which in turn makes the "finishing process more expensive."

Furthermore, the tear resistance of normally finished abrasive raw fabrics becomes on the basis of regenerated cellulose, especially Folynosic fibers, greatly reduced.

It has now been found that the above-described Disadvantages can be avoided if you go for the abrasive fabric sheet an abrasive backing fabric made from regenerated cellulose fibers «, especially of the. polynosian! fibers, used this being characterized in that

a) the warp thread sighted and finished and the Plain and finish without. Adhesive boundary layer connected. and

b) the weft thread has a finish.

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A special embodiment of the abrasive grain carrier web is characterized in that the warp thread is provided with a core size (core size - see ADHÄSION magazine, year 1961, No. 10 - pages 5Θ5-512 and No. 11 - pages 564-577 and Fo. 12 - Pages 617-622 in the article on "Schlichteinittel für die Textilindustrie" by Erich P. Prieser.) " - ~ ~ \" -

In a further embodiment, the soft grain carrier fabric web is characterized in that the finish on the warp thread and weft thread is made by finishing with a finishing agent which; emulsified in an aqueous medium containing organic solvent, which at temperatures of 15 - is a solvent for the located on the warp sizing a 200 ° 0 ,. - 45 ⁰ C, a swelling agent, and about 65 has been ordered.

A web of abrasive grain fabric backing produced in this way has the great advantage that the abrasive fabric finish adheres firmly is firmly connected to the core-sized warp thread and the weft thread, ■ ".---".

At dea? Manufacture of the present web of abrasive grain backing fabric there is the advantage that none in the finish large amounts of finishing agent have to be applied because the warp thread is already core sized. Also will due to the new arrangement in the abrasive grain carrier fabric web a high elasticity of this is achieved.

As a size for the warp thread or, preferably, a core size is useful, for example:, degraded starch and starch

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derivatives ₉ resins based on isocyanates _s homo-and / or copolymers of acrylic compounds (butyl, methyl acrylate), polyvinyl alcohol, polyvinyl acetate, acrylonitrile-butadiene-styrene copolymers in the form of solutions or dispersions and appropriate wetting agent, for example naphthalene, Acry derivatives! or ethoxy adducts.

Preferred core sizes are polymers based on acrylates and their derivatives as well as oxidatively and / or acid-degraded starch products and fatty acid condensation ethoxy adducts. As a finishing for the warp thread and for the weft thread, for example: animal hide glue and / or reactive and non-reactive copolymeric acrylate solutions or aqueous dispersions j polyisocyanates polystyrene, N-methylol compounds of urea and its derivatives, aldehydes and its derivatives sulfone compounds, -Phenor-Pormaldehyd resole resins, polyvinyl alcohol, acetate and chloride in the form of dispersions and solutions epoxy undPolyesterharze as well as starch, starch derivatives and _s Äthoxyaddukte said emulsified in an aqueous medium containing organic solvents ₉ which at temperatures of 15 - 45 ° C a swelling agent and about 65 to 200 ⁰ C is a solvent for the located on the warp yarn sizing. Suitable emulsifiable organic solvents are, for example, toluene, xylene, ethyl acetate, white spirit, trichlorethylene, perchlorethylene. Preferred finisher are self-crosslinking acrylate copolymers particularly copolymers of _s-butyl and ethyl acrylate and methyl methacrylate in Basie dispersion or solvent-dissolved form. ■ ".'_...

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The following special advantages are achieved through the use of the preferred finishing agents, since the crosslinking acrylate dispersions, as a finishing agent for the phenolic base resins to be applied later, have good adhesive properties; this also avoids embrittlement of the fabric. In addition, the abrasive grain backing fabric web can be provided with the same finish on both sides of the web, as is achieved by a dipping process or a double-sided coating process. .- .-. ; - ^; >.

The abrasive grain carrier fabric web equipped in this way is placed on a coating or coating system, for example coated with the following binders:

a) plain weave; _ hide glue or _: phenolic resole resin

and then the. Abrasive grain, for example Silicon carbide, mechanically or electrostatically sprinkled and subsequently pre-dried or, not pre-dried with a ^

b) Deck binder / on the basis of: -from provided Haütleim, or phenolic resole resin, urea-formaldehyde resin and the curing oven at about 60 - 140 ⁰ C in a conventional manner, dried and cured.

The finished abrasive fabric web; is then used to produce Abrasive cloth tapes, sleeves, skirts, sheets and the like.

A modified form is achieved by applying an intermediate layer on the finished tissue. as described in the German utility model 1-901 340, example 5, is achieved. Then, as described above, the "basic bond"

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resin applied. '

Example 1 . \

I am a 28/30 size warp yarn made from regenerated cellulose fiber (Polynosic-Iyp). in a sizing trough with a Recipe, "consisting of -. -

80 parts by weight starch digested by acid degradation

3 Grew * parts of Ithoxyad-duct . 917 parts by weight of water.

core-sized and dried on a cylinder drying machine and then woven into a raw abrasive fabric. The raw abrasive cloth produced in this way is without desizing with a finish consisting of

50 parts by weight of animal hide glue

(300 sheets _? 100 mp)

100 parts by weight of a - '.. copolymeric acrylate dispersion

50 parts by weight kaolin. .

3 parts by weight: Haph thai insul f onat

797 parts by weight of water

impregnated and with simultaneous stretching with a lateral jump of approx. 11.5. $ Dried and fixed, then, with hide glue, the class (300 Bl.g. 100 mp) coated and electrostatically sprinkled silicon carbide without pre-drying and then immediately the same hide glue as for the plain weave, coated as Deekbindungsleim and at 60-120 ⁰ C. dried and then flexed and reconditioned. . . ".-. ' ...

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The abrasive fabric obtained in this way is used for dry sanding as Tape-.lind sheet goods processed.

Example 2 ■ ', ... ".

A warp yarn made from regenerated cellulose fibers (Polynosic type) the ITm 26 is placed in a sizing trough with a fleet, ordering from -

120 parts by weight of reactive .copolymer acrylate dispersion 5 parts by weight of water-soluble copolymer is made up of

30 fo acrylic acid, 70 </ o butyl acrylate

875 parts by weight of water

sizing, and then drying and fixing in an air duct at 140 ^{° C.}

120 parts by weight of reactive copolymeric acrylate dispersion

5 parts by weight of a copolymer «from; \ -30 fo acrylic acid and 70 $ butyl acrylate

20 parts by weight of toluene
60 parts by weight, kaolin
20 parts by weight of dimethyloldihydroxyethylene urea

2 parts by weight of magnesium chloride 773 parts by weight of water

impregnated and under. Stretching at 140 ⁰ O dried - the fabric jumps in width by 11.5 ίο - and fixed .. Then, - as described in the German utility model 1 901 340, an intermediate plastic layer on the finished abrasive grain carrier fabric web, as there in Example 3 described, applied and then after

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Drying coated with a phenolic resole resin and electro corundum or silicon carbide applied electrostatically. Phenolic resin is applied as a top binder and then ' dried and hardened at 50 - 14o ° C »

The abrasive cloth obtained in this way is suitable for wet sanding tapes.

To prove the technical port step, the abrasive cloths produced in this way were subjected to a mechanical breaking process - referred to in the technology of abrasive cloth production as "Flexen ' ¹ " - and processed into abrasive cloth tapes. These were stretched on a belt grinding machine and tested in the test grinding process Schlsifgewebe with a conventionally _s then sized not desized and then conventionally appretierten abrasive backing fabric prüfschleiftechnisch compared "at constant pressure load of the sanding was carried out from a defined Eisehrohr. Furthermore, the surface of the abrasive cloth was visually observed after Prüfschleifvorgang in terms of stock removal and grain break. applies as a standard of value In each case the grinding time achieved until the abrasive grain broke out completely Tested with a phenolic resin intermediate layer and lamination of this sample using the same phenolic resin on sheet metal. The sample was cured and, after air conditioning, the peel strength and the peel point were determined.

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Belt grinder grain breakout from tissue according to:

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Peel test

Peeling takes place

1 minute

β kg

12 minutes

15 kg

between plain u.

finish

between phenolic resin and finish

Conventionally sized sole fabric _9, not desized and conventionally impregnated

Abrasive fabrics sized according to the invention with sizing and finishing according to the invention, impregnated and coated with a _second finish as described in German Patent 1,226,451

The tests show that the abrasive sheet ₃ is present improved according to the present invention in several respects, surprisingly, .. - ..

The abrasive grain fabric web of the invention is through the Drawings clarified. '..

FIG. 1 shows the abrasive grain carrier 8 _5, where FIG. 1 represents the core sized and first finished warp thread and illustrates the first finished weft thread.

FIG. 2 shows the structure of that treated according to the invention Abrasive sheet, 8 being the abrasive grain carrier shown in FIG illustrated and provided with the fabric finish according to the invention. The abrasive grain binders 6, consisting of the base binder 4 and the top binder are clearly reproduced. As: abrasive grit layer 3 is for example Electro-corundum or silicon carbide can be used in the grit gradations customary in the abrasive industry. aside from that is the one described in the German utility model 1 901 3 ^ 0 Molding compound additionally applied as an intermediate layer 9 again-

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given. .: ■

Pigu: 3 shows a cut as an abrasive cloth tape ₃

Figure 4 shows a blank as an abrasive cloth sleeve

FIG. 5 shows a blank as an abrasive cloth cone ₃

FIG. 6 shows an abrasive cloth sheet.

Example 1 can be used as a copolymeric acrylate dispersion made up of;

1-7% by weight acrylamide.

1-5% by weight methacrylic acid.

5 ~ 15GeWo # methyl methacrylate

Residue wt.% Ethyl acrylate.

be used" /

In example 2, a reactive copolymeric acrylate dispersion can be used., Composed of:

a.) at least 2 - 15% by weight, an N-methyl group-containing oil of copolymerized monomer _3, for example, N-methylol acrylamide, 5 - 10 wt "% acrylonitrile and the balance ethyl ^acrylate,: -

or

b) 5-0. "X weight vinyl acetate

30 - Ho wt. ^ Butyl acrylate
2-15 wt =% N-methylolacrylamide

or

c) residual Ithylacrylat% wt.
5-15 Qew ..- i Acrylonitrile ■ ' ^: .

- 5-15 Gevio% N-methylolacrylamide.

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The particular advantages are that one uses an abrasive grain carrier fabric web made of regenerated cellulose fibers - in particular of the polynosic fiber type, whereby
a) the warp thread with a size chemically constructed in this way

sized, is that the size adheres firmly to the finishing agent that is later applied to the finished fabric without the occurrence of an anti-adhesive boundary layer ₃

b) i.cr so pretreated warp thread with a weft thread from an abrasive backing fabric is used ₃

c) the finished abrasive backing fabric as opposed to the normally required _s many operations requiring appreturtechnischen wet treatment is appretiert for removing the sizing and Reinigung'des tissue directly with a chemically matched to the sizing without finisher _s daß.Störungen in the adhesion between ..Appreturmittel and tissue occur. The abrasive fabric web has particularly advantageous properties / if it is provided with the abrasive grains with abrasive grains in the medium and / or micro-range. These are grain sizes 120 - 220 and 24O and finer "(Pepa micro grain sizes - standard for abrasive grain (German Fepa -Series) professional association. Electro-corundum and silicon carbide manufacturers

Claims (1)

Protection claims 1. Abrasive fabric web with an abrasive grain _{backing fabric web of regenerated cellulose fibers 3,} in particular of the polynosic fiber type, characterized in that a) the warp thread is sized and finished and the size and finish adheres firmly without a boundary layer connected is
and
b). the weft thread has a finish. 2 »Abrasive fabric sheet after. I claim ₃ characterized in that the warp thread ₃ is provided with a core sizing " 3 »abrasive fabric web according to claim 1 or 2 _S wherein j that the abrasive grain carrier fabric web the padding located on the warp yarn and the weft yarn by padding with a finisher ₃ which emuIgiertes in the aqueous medium organic solvent _s containing at temperatures of 15 - 45 ° C, a swelling agent and about 65-200 ⁰ C, a solvent for the located with the warp thread sizing is ₃ is arranged.