CA1153512A

CA1153512A - Asbestos-free rubberized flooring felt

Info

Publication number: CA1153512A
Application number: CA000344110A
Authority: CA
Inventors: Roger K. Landis; Donald H. Benninger
Original assignee: Armstrong World Industries Inc
Current assignee: Armstrong World Industries Inc
Priority date: 1979-06-04
Filing date: 1980-01-21
Publication date: 1983-09-13
Also published as: GB2051170B; IT8022535A0; LU82277A1; DK239480A; BE883386A; NL8003263A; NO801442L; AU527585B2; GB2051170A; JPS564779A; IT1131256B; DE3006042A1; DE3006042C2; AU5834280A; FR2458623A1; JPS5858474B2; FR2458623B1; SE8004109L

Abstract

Abstract of the Disclosure A beater-saturated, water-laid, asbestos-free rubberized flooring felt which exhibits dimensional stability is 5 disclosed. The felt is well suited for use in thc production of floor coverings and is p;oduced cy removing water from an aqucous furnish composition comprising glass fibers, cellulose pulp, fibrillated polyolefin fibers, inorganic fille., a soluble salt selected from the group consistinq of aluminum 10 salts, ferric salts and stannic salts, and a sufficient amount of ar alkaline hydroxide to provide a furnish pH within the range from about 6 to about 10, said alkaline hydroxide serving to convert the soluble salt to a water insoluble hydroxide.

Description

-11535~Z

1 - D~K-6219 & 6313 ASBESTOS-FRE~ RUBBERIZED FLOORING FELT

This invention relates to asbestos-free, rubberized felts.
~ lore specifically, this invention relates to beater saturated, water-laid, asbestos-free, rubberized felts which are dimensionally stable and, accordingly, are well suited for use as felt backing sheets for resilient flooring.
Asbestos-containing rubberized felts are well known and have achieved unprecedented commercial success in the resilient flooring industry as backing or foundation sheets for decorative floor coverings. These asbestos-containing rubberized felts are produced by beater saturating asbestos fibers with a rubber latex in an aqueous system and forming the felt product on conventional papermaking equipment. See, for example, U. S. Patent Nos.

2,375,245; 2,fil3 190; and 2,759,~13. The commercial success of these asbestos-containing rubberized felts has been primarily due to the physical and chemical properties imparted to the felts by the asbestos fibers. The asbestos fibers alone facilitate the produc-tion of felts which can be easily processed, are dimensionally stable, exhibit excellent hot tensile strength and are alkali, moisture and microbiologically resistant~ ~o other single fibrous material is known which can replace asbestos fibers in flooring felts and provide felts having acceptable properties, especially dimensional stability and hot tensile strength.

- 2 - DMK-6219 & 6313 ~ he health hazard problems of asbestos fibers are alæo well known and, accordingly, the flooring industry has long been searching for replacement flooring felts which do not contain asbestos fibers but yet achieve substantially the same physical and chemical properties as the prior art asbestos-containing rubberized felts. Especially important and critical in the flooring industry is that the replacement flooring felt be dimensionally stable and exhibit good hot tensile strength.
If a flooring felt does not exhibit good hot tensile strength, it will not withstand conventional, resilient floor covering processing temperatures.
If a flooring felt is not dimensionally stable, it will grow when exposed to moisture, thus causing growth in the entire floor covering. This growth presents a major installation problem.
During installation when the felt comes in contact with wet adhesive it grows and~this growth results in the distortion of an in-register decorative pattern at double cut seams. This growth can also result in buck]es or wrinkles in the floor covering.
The present invention helps solve the above problems and provides a beater saturated, water-laid, asbestos-free, rubberized felt which is dimensionally stable.
For the purposes of this invention, a felt which exhibits more than +0.30~ change in its cross machine twidthwise) direction i.s considered tv be unsuited for use to produce floor coveringsO
As used herein, the term "dimensional stability" means that t:he flooring felt exhibits +0.30~ or less and, preferably, +0.2d~ or less growth change in its cross machine (widthwise) direc-tion when ~ested according to the standaræized High Humidity Dimensional Stability Test procedure set forth below.
Two l" by 9" samples of the felt to be tested are cut from the felt in its cross machine (wi~thwise) direction. If testing a felt handsheet made in a handsheet mold which has no machine or cross machine direction, the direction of cut is not important.
Each sample is tested individually as follows:

llS3512

- 3 - DMR-6219 & 6313 Hi~h ~umiditv Dimensional Stability Test conditions (1) The sample is placed in a circulating air oven and heated for six hours at 180-F.
(2) The sample is removed from the oven and cooled in a desiccator over CaC12 for 1/2 bour at 73.4- F.
(3) The sample is removed from the desiccaSor and the distance between two reference points ~initial distance) is measured accurately to a thousandth of an inch.

(4) The sample is then placed in a humidity cabinet and heated for 24 hours at 100-F and 90% rela-tive humidity.

(5) The sample is removed from the humidity cabinet and cooled in a desiccator for 1/2 hour over water.

(6) The sample is removed from the desiccator and the distance between the two reference points remeasured (final distance) accurately to a thousandth of an inch, and the initial distance is subtracted from the final distance to give the change in inches.
The resulting change in inches is divided by the initial distance in inches and multiplied by 100 to give the % change for each sample.
The % change of each of the two samples are averaged to give the %
change in widthwise direction which is the unit of measure for dimen-sional stability. Reference is made to Federal Standard 501a, Method 6211.

~lS351Z
- 4 - DM~-6219 ~ 6313 ~ ccording to this invention, there is provided a beater .saturated, water-laid, asbestos-free, rubberized flooring felt which is dimensionally stable, produced by removing water from an aqueous furnish composition comprising glass fibers, cellulose pulp, fibrillated polyolefin fibers, at least one inorganic filler, a synthetic rubber binderr a soluble salt selected from the group con-sisting of aluminum salts, ferric salts and stannic salts, and a sufficient amount of an alkaline hydroxide to provide a furnish p~
within the range from about 6 to about 10, the alkaline hydroxide serving to convert the soluble salt to a water insoluble hydroxide.
Also according to this invention there is provided a sur-face covering comprising (a) a beater saturated, water-laid, asbestos-free rubberized flooring felt which is dimensionally stable produced by removing water from an aqueous furnish composition comprising glass fibers, cellulose pulp, fibrillated polyolefin fibers, at least one inorganic filler, a synthe~ic rubber binder, a soluble salt selected from the group consisting of aluminum salts, ferric salts, stannic salts and a sufficient amount of an alkaline hydroxide to provide a furnish pH within the range from about 6 to about 10, the alkaline hydroxide serving to convert the solubl~ salt to a water insoluble hydroxide and (b) a decorative wear surface joined to the rubberized flooring felt.
In its preferred form, the aqueous furnish composition will also include a papermaking wet strength resin and a latex antioxidant. Optionally, the aqueous furnish composition can con-tain retention aids, biocides and the like.

~153S12 - S - DMR-6219 & 6313 The aqueous furnish composition will contain from about 1 to about 10 parts by weight of conventionally surface treated chopped glass fibers per 100 parts of the total fiber and filler weight.
Suitable glass fibers will have nominal fiber lengths within the range of from about 1/16" to about 1/2" and nominal fiber diameters within the range of from about 0.0002" to about o.ooosn.
Two parti~ularly suitable chopped glass fibers are available from Owens-Corning Fiberglas* Corporation as 1/8" "D-E 636 Glass Fibers" and 1/8 n nD-E 670-8 Glass Fibers.~
The aqueous furnish composition will contain from about 2 to about 20 parts by weight of cellulose pulp per 100 parts of the total fiber and filler weight. In this invention, for the purpose of determining amounts of ingredients, cellulose pulp is considered a fiber ingredient. Any suitable cellulose pulp ~an be ~mployed, including bleached and unbleached sulphite pulp, softwood pulp, kraft pulp, ~ewspaper pulp, and the like. A particularly suitable cellulose pulp is ~Unbleached Sulphite Pulp" available from ITT
Rayonier.
Any suitable fibrillated polyolefin fibers can be employed in an amount of from about 1 to about 20 parts by weight fibrillated polyolefin fibers per 100 parts of the total fiber and filler weight. Particularly suitable fibrillated polyolefin fibers are fibrillated polyethylene fibers and fibrillated polypropylene fibers.
A particularly suit~ble fibrillated polyethylene fiber is grade E-620 "Fybrel*" commercially available from Crown Ze11erbach Grade E-620 Fybrel* has an average weighted fiber length of 1.3mm as measured in a Bauer-McNett classifier and a drainage factor of 6 seconds/gram. The drainage factor equals the drainage rate of a 10 gram sample measured in a Standard sritish handsheet mold expressed in seconds per gram.

*Trademark ~15351Z
- 6 - D.~-6219 ~ 6313 Other fibrillated polyolefin fibers which are sultable for use are grades E-400, E-600, E-780, E-790, and R-830 of l'Fybre1*,';
all commercially available ~rom Crown Zellerbach, grades A and D of "Pulplex E*" both fibrillated polyethylenes available from Bercules, Inc., and ~rade AD, "Pulplex P*" a fibrillated polypropylene also available from Hercules, Inc.
~ he aqueous furnish composition will contain at least one inorganic filler present in an amount within the range of ~rom about 50 to 96 parts by weight total inorganic filler per 100 parts of the total fiber and filler weight. The inorganic filler will be selected from the group consisting of paper filler clay, wollastonite, talc, calcium carbonate, mica, pyrophyllite ~nd diatomaceous earth.
Particularly suitable fillers include wollastonite of P-4, P-l, or C-l grade, all commercially available from Interpace Co. and Koalin Clays designated "Hi-Opaque Clay*," commerciall~ available from Freeport Kaolin Clay Co., and "Klondyke*" clay or "K1Ondyke KWW*" clay, both commercially avai~abl`e from Engelhart Minerals & Chemicals Corp.
Pyrophyllite is a hydrous aluminum silicate and is commercially available as "Pyrax*" from R.T. Vanderbilt Company, Inc.
The aqueous furnish composition will contain from about 10 to about 40 parts by weight add-on of a synthetic rubber latex per every 100 parts of the total fiber and filler weight. Any suitable synthetic rubber latex can be be employed including styrene/butadiene late~es, carboxylated styrene/butadiene latexes, polychloroprenes, carboxylated polychloroprenes, vinyl pyridene/styrene/butadiene terpolymers, and the like. Carboxylated styrene/butadiene latexes are particularly suitable for use in this invention, one such material being designated "Dylex* 1187," commer-cially available from Arco* Polymers, ~ ., a subsidiary of tlle Atlantic Richfield Company. Dylex* 1187 has a total solids of about 44 to 50 weight percent, a pH of from 9 to 10, a surface tension of 60 to 70 dynes/cm., a Brookiield viscosity of 1 to 300, and weighs 8.40 pounds/gallon.
The aqueous furnish composition will preferably contain from about 0.02 to about 2 parts by weight add-on of a conventional papermaking wet stren~th resin per 100 parts of the total fiber and filler weight. Particularly suitable wet strength resins are *Trademark ~535~2

- 7 - DMR-6219 & 6313 designated "Kymene* 2064" and "Kymene* 557H," both commercially available from Hercules, Incorporated. Kymene* 2064 and Kymene* 557H
~re water ~olutions of cationic amine polymer-epichlorohydrin adducts.
S The a~ueous furnish composition will preferably contain from about 0.2 to about 1.6 parts by weight add-on of a latex antioxidant per 100 par~s of the total fiber and filler weight. A
particularly suitable latex antioxidant is designated "Flectol H,*"
com~ercially available from Monsanto Industrial Chemicals Company.
10 Flectol H* is polymerized 2,2,4-trimethyl-1,2-dihydroquinoline.
The foll~Jing examples demonstrate the preparation of dimensionally ctable, asbestos-free rubberized flooring felts of this invention.
ExamDle I
This mixing procedure is based on the preparation of an a~ueous furnish using the following ingredients. ~11 amounts of ingredients are in parts per 100 parts by weight of the total fiber and filler weight.
In~redients Amount glass fibers (1/8" D-E 636, Owens-Corning Fiberglas) 2.25 fibrillated polyethylene (grade E-620 Fybrel) 2.75 cellulose pulp unbleached sulfite pulp (ITT Rayonier) 7.5 softwood pulp (Westvaco*) 2.5 filler wollastonite (P-4) 60 clay (Hi-Opaque*) 25 Total 100 -antioxidant (F'ectol H) 0~4 wet strength resin (Kymene 5;7~) 0.4 synthetic rubber latex (Dylex 1187) 17 aluminum sulfate 7.65 *Trademark .. . .

~1535~Z

- 8 - DMR-6219 & 6313 To a mixing vessel containing about 300 milliters of ~ap water were added the total amounts of the glass fibers, fibrillated polyethylene~ cellulose pulp, filler, and antioxidant. The contents of the mixing vessel were slurried for about 1/2 to 1 minute to insure full dispersion of the ingredients.
The slurry was then diluted with tap wa.er at a tem-perature of about 75-F. to a total volume of 2.3 liters at 2~ con-sistency and homogenously mixed using an air stirrer.
To the resulting homogeneous mixture was added the total amount of wet strength resin with stirring for about one minute.
Next, the total amount of aluminum sulfate was added with stirring for about 2 minutes, followed by the addition of ammonium hydroxide to a slurry pH of about 7 to 7.5 The total amount of synthetic rubber latex was then added lS with stirring for about 5 minutes until the latex precipitated, that is, the latex deposited on the fibers and fillers thus serving as a drainage aid and a binder in the resulting felt.
The resulting slurry was then formed into a handsheet using a conventional Williams handsheet mold. The resulting handsheet was then wet pressed to remove excess moisture and drum dried at a temperature of about 230-F.
The resulting dried handsheet was recovered as rubberized flooring felt of this invention suitable for use to produce resi-lient floor coverings. The felt was tested and found to have a gauge, after calendering, of about 0.025 inch.
Exam~le II
This mixing procedure is based on the preparation of an aqueous furnish using the following ingredients. All amounts of ingredients are in parts per 100 parts by weight of the total fiber and filler weight.

~lS3SlZ

- 9 - DMK-6219 & 6313 Ingredients Amount ~lass fibers ~l/8" D-E 670-8; Owens-Corning Fiberglas) 2.5 fibrillated polyethylene (grade E-620 Fybrel) 2.75 cellulose pulp newsprint pulp 8 softwood pulp (l~estvaco) 2 filler wollastonite (C-l) 55 clay (I~londyke) - 29.75 Total 100 antioxidant (Flectol H) 0.5 wet strength resin (Kymene 2064) 0.5 synthetic rubber latex (Dylex 1187) 17 aluminum sulfate 7.65 To a mixing vesse] containing about 300 milliters were added a total amount of glass fibers, fibrillated polyethylene, cellulose pulp, filler and antioxidant. The contents of the mixing vessel were slurried for about 1/2 to 1 minute to insure full dispersion of the ingredients.
The slurry was then diluted with tap water at a tem-perature o about 75-F. to a total volume of 2.5 liters at 2~ con-sistency and homogeneously mixed using an air stirrer.
To the resulting homogeneous mixture was added the total amount of wet strength resin with stirring for about 1 minute.
Next, the total amount of aluminum sulfate was added with stirring for about 2 minutes followed by the addition of ammonium hydroxide to a slurry pM of about 7 to 7.5.

1~5351Z

- 10 - DMK-6219 ~ 6313 The total amount of synthetic rubber latex was then added with stirring for about 5 minutes until the latex precipitated, that is, the latex deposited on the fibers and fillers thus serving as a drainage aid and a binder in the resulting felt.
The resulting slurry was then formed into a handsheet : using a conventional Williams handsheet mold. The resulting handsheet was then wet pressed to remove excess moisture and drum dried at a temperature of about 230-F.
The resulting dried handsheet was recovered as a rub-berized flooring felt of this invention suitable for use to produce resilient floor coverings. The felt was tested and found to have a gauge of about 0.0246 inch.
ExamPle III
Using substantially the procedure of Example II, a handsheet was prepared using the following ingredients.
Ingredients Amount glass fibers (1/8" D-E 670-8: Owens-Corning Fiberglas) fibrillated polyethylene (grade E-620 Fybrel) 2.75 20 cellulose pulp newsprint pulp 8 softwood pulp (~estvaco) 2 filler wollastonite (C-l) 55 clay (I~londyke) 31.25 Total 100 ~-antioxidant (Flectol H) 0.5 wet strength resin (Kymene 2064) 0.5 synthetic rubber latex (Dylex 1187) 17 30 aluminum sulfate 7.65 ~1S3S~2

- 11 - DMK-6219 & 6313 The resulting handsheet was recovered as a rubberized flooring felt of this invention suitable for use to produce resi-lient floor coverings. The felt was tested and found to have a gauge of about 0.0240 inchO
Example IV
Using substantially the procedure of Example II, a handsheet was prepared using the following ingredients.
Ingredients Amount glass fibers (1/8" D-E 670-8; Owens-Corning Fiberglas) 1.67 fibrillated polyethylene (grade E-620 Fybrel) 2.75 cellulose pulp newsprint pulp 8 s,oftwood pulp (Westvaco) 2 15 filler wollastonite ~C-l) 55 clay (Rlondyke) 30.58 Total 100 antioxidant (Flectol H) 0.5 20 wet strength resin (Kymene 2064) 0.5 synthetic rubber latex (Dylex 1187) 17 aluminum sulfate 7.65 The resulting handsheet was recovered as a rubberized flooring felt of this invention suitable for use to produce resi-25 lient floor coverings. The felt was tested and found to have a ;
gauge of about 0.0250 inch.

11535~2

- 12 - DMK-621~ & 6313 Examp:Le V
Using substantially the procedure of ~xample II, a handsheet was prepared using the following ingredients.
In~redients Amount glass fibers (1/8" D-E 670-8; Owens-Corning Fiberglas) 1.25 fibrillated polyethylene ~grade E-620 Fybrel) 2.75 cellulose pulp newsprint pulp 8 softwood pulp (~estvaco) 2 filler wollastonite (C-l) 55 clay (Klondyke) 31 _ Total 100 antioxidant (Flectol H) 0.5 wet strength resin (Kymene 2064) 0.5 synthetic rubber latex (Dylex 1187) 17 aluminum sulfate 7.65 The resulting handsheet was recovered as a rubberized flooring felt ~f this inven~ion suitable for use to produce resi-lient floor coverings. The felt was tested and found to have a gauge of about 0.0250 inch.
Exam~le VI
Using substantially the procedure of Example II, a handsheet was prepared using the following ingredients. This slurry was diluted to a total volume of 2.5 liters at 1.25~ consistency instead of 2~ consistency.

`~ ~
l~S3~;~Z

- 13 - DMK-6219 ~ 6313 Ingredients Amount glass fibers ~lt8" D-E 670-8; Owens-Corning Fiberglas) 5 fibrillated polyethylene (grade E-620 Fybrel) 20 cellulose pulp newsprint pulp 15 softwood pulp tWestvaco) 5 filler wollastonite (C-l) 35 ~'~
clay ~Klondyke) 20 Total 100 antioxidant (Flectol ~) 0.5 wet strength resin (Kymene 2064) synthetic rubber latex (Dylex 1187) 20 aluminum sulfate 9 The resulting handsheet was recovered as a rubberized flooring felt of this invention suitable for use to produce resi-. lient floor coverings. The felt was tested and found to have a gauge of about 0.0250 inch.
Example VII
Using substantially the procedure of Example II, a . handsheet was prepared using the following ingredients.
Ingredients Amount : glass fibers (1/8" D-E 670-8; Owens-Corning Fiberglas) 1 .

fibrillated polyethylene (grade E-620 Fybrel)

- 14 ~ DMK-6219 ~ 6313 Ingredients Amount cellulose pulp newsprint pulp 1.5 softwood pulp (Westvaco) 0.5 filler wollastonite (C~l) 64 clay tKlondyke) 32 __ Total 100 antioxidant (Flectol H) wet strength resin (Kymene 2064) 0.1 synthetic rubber latex (Dylex 1187) 40 aluminum sulfate 13.2 The resulting handsheet was recovered as a rubberized flooring felt of this invention suitable for use to produce resi-lient floor coverings~ The felt was tested and found to have a gauge of about 0.0303 inch.
Example VIII
Using substantially the procedure of Example II, a handsheet was prepared using the following ingredients. This slurry was diluted to a total volume of 2.5 liters at 1.33% consistency instead of 2% consistency.
Inqredients Amount -glass fibers (1/8" D-E 670-8; Owens-Corning Fiberglas) S .i fibrillated polyethylene (grade E-620 Fybrel) 10

- 15 - DM~-6219 & 6313 Inqredients Amount cellulose pulp newsprint pulp 15 softwood pulp (~estvaco) 5 filler wollastonite (C-l) 45 clay (Klondyke) 20 Total 100 antioxidant (Flectol H) 0.
wet strength resin (Kymene 2G~4) synthetic rubber latex (Dylex 1187) 20 aluminu~ sulfate 8 The resulting handsheet was recovered as a rubberized flooring felt of this invention suitable for use to produce resi-lient floor coverings. The felt was tested and found to have a gauge of about 0.0236.
Exam~le IX
This example demonstrates the best mode of preparing the asbestos-free rubberized flooring felt of this invention.
20In~redients Amount glass fibers (1/8" D-E 670-8: Owens-Corning Fiberglas) 2.25 fibrillated polyethylene (grade E-620 Fybrel) 2.75 f cellulose pulp 25unbleached sulfite pulp (P-10) 7.75 softwood pulp (Westvaco) 2.25 11535~z

- 16 - DMK-6219 & 6313 In~redients _mount filler wollastonite (P-l) 55 diatomaceous earth 6 clay slurry "Klondyke K~l" 24 Total 100 antioxidant (Flectol H) 0.8 wet strength resins (Kymeme 2064) 0.25 synthetic rubber latex (Dylex 1187) 20 retention aid (Hydraid 5501 - Merck & Co.) 0.06 ?
aluminum sulfate 7.65 To a hydrapulper containing water were added the total amounts of cellulose pulp, fibrillated polyethylene fibers, filler, and antioxidant. The contents of the hydrapulper were slurred for lS about 10 to lS minutes to ensure full dispersion of the ingredients.
The slurry was fed sequentially through Jordan refin-ers, a holding tank, and into a precipitation tank where it was diluted with water at 3% consistency and where the total amounts of glass fibers, synthetic rubber latex, wet strength resin, aluminum sulfate and ammonia hydroxide were added with stirring for about 3 to 5 minutes. The batch weight of 100 parts of the fiber and filler in the precipitation tank was 2,500 pounds.

~53S12

- 17 - DMK-6219 & 6313 The total amount of the retention aid was added to the furnish as it was pumped from the precipitation tank to a conven-tional Fourdrinier machine where it was formed into a felt of this invention. The felt was wet pressed to remove excess moisture and drum dried at a temperature of about 275- to about 300-F.
The resulting felt was recoverd as a rubberized flooring felt of this invention, and used to produce resilient iloor covering. The felt was tested and found to have a gauge, after calenderin~, of about 0.0240 inch.
The following Table I illustrates physical and chemical property data on the asbestos-free felts of Examples I-IX as com-pared to representative average property data of conventional prior art asbestos-containing rubberized felts:

~.;., 1~53S~LZ
I ~ ~ 11~ D d' ~``1 In c ~ .t~ . co ~ ~ t~ o ~D
O ~1 ~ ~ ~
V ~ O ~ 1~ D O
tU ta O tJ O -t Q V~ ~4 O p~
~ d'~ ~ t,~1 W
H t~11-)ID ~
O ~ +

Ht`~ . U) a) a~If~ O
H~`I t~
r-l -J O
+
::
H t~
H O ~ ID ~ ~101 ~1 U) :~tr~~D ~O
O1~ ~ o O +

~ ~ ~ ~t~U~
o ~ ~t~t,~i o O ~ +

. ~ U')tD If~
r o 1~
o ~ ~ In t'~t.~l o O +
I) ta Il~ G~ t~
X ~t'~l tr~ o ~D
0 ~Ll H O ~D ~ o O O ~ +
V V
~ tIt~ ~o~ In t,~
H O ID U'ler ~ E-~ O
O ~1~ +
~ V
.~ a ,t~l In t~ . . tn V
H O ~ U')tl7 ~1 0U~ O

Sv ot~ In N
Il~ ~ O ~ I~ tO tlJ
H ~ tY')I~
olt~ o o ~ +
a, ,~ rn c~ v o ',~ ~
14 S --I tJ
t~ U~ ~ 3 ,_ tY) -- r ) ~n ~n ~ V ~l ~ op vt~ ~ o v v v r~ t~ tav o t!) ~ ~ ^ ^ V ., ~ _ ~. ~ 0~ rn ~ m o O ri Q t~ z Q~ ~ VV r r ~a 3 t-tn U~ U~ "0, ,,, OC S ~ O.~
, ~ ~ v v G~ r~ O
t~ In ~n tn r~ C ~ s ~a C
c c c o o W ~3 a ~5;:~S~L2 - l9 - DMK-6219 & 6313 The above data indicate that the asbestos-free rubberized felts of this invention exhibit excellent dimensional stability under high humidity conditions while possessing acceptable physical and chemical properties as compared to the prior art asbestos-containing rubberized felts.
To the asbestos-free rubberized felts with the composition of this invention can be laminated, using conventional methods, a conventional decorative surface covering such as a vinyl wear layer to make a floor covering.

~ j.7 ': .

Claims

- 20 - DMK & 6313 WHAT IS Claimed IS:

1. A beater saturated, water-laid, asbestos-free, rub-berized flooring felt which exhibits dimensional stability produced by removing water from an aqueous furnish composition comprising glass fibers, cellulose pulp, fibrillated polyolefin fibers, at least one inorganic filler, a synthetic rubber binder, a soluble salt selected from the group consisting of aluminum salts, ferric salts and stannic salts, and a sufficient amount of an alkaline hydroxide to provide a furnish pH within the range of from about 6 to 10, said alkaline hydroxide serving to convert said soluble salt to a water insoluble hydroxide.

2. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 further containing a papermaking wet strength resin.

3. The beater saturated, water-laid, asbestos-free, rubberized flooring felt of claim 1 further containing a latex antioxidant.

4. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 in which said glass fibers are employed in an amount within a range of from about 1 to about 10 parts by weight per 100 parts of the total fiber and filler weight.

5. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 in which said cellulose pu12 is employed in an amount within a range of from about 2 to about 20 parts by weight per 100 parts of the total fiber and filler weight.

6. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 in which said fibrillated polyole-fin fibers are employed in an amount within a range of from about 1 to about 20 parts by weight per 100 parts of the total fiber and filler weight.

- 21 - DMK-62l9 & 6313

7. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 in which said at least one inorga-nic filler is selected from the group consisting of paper filler clay, wollastonite, talc, calcium carbonate, mica, pyrophyllite and diatomaceous earth.

8. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 in which said at least one inorga-nic filler is employed in a total amount within a range of from about 50 to about 96 parts by weight per 100 parts of the total fiber and filler weight.

9. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 2 in which said papermaking wet strength resin is employed in an amount within a range of from about 0O02 to about 2 parts by weight add-on per 100 parts of the total fiber and filler weightO

10. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 3 in which said latex antiox:idant is employed in an amount within a range of from about 0.02 to about 1.6 add-on parts by weight per 100 parts of the total fiber and filler weight.

11. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 in which the ratio in parts by weight of fiber to filler is 1:24 to 1:1.

12. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 having a dimensional stability of +0.30% or less when subjected to the High Humidity Dimensiona Stability Test conditions.

- 22 - DMK-62l9 & 6313

13. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 1 having a dimensional stability of +0.20% or less when subjected to the High Humidity Dimensional Stability Test conditions.

14. A beater saturated, water-laid, asbestos-free, rub-berized flooring felt which exhibits dimensional stability produced by removing water from an aqueous furnish composition comprising in parts by weight per 100 parts the total fiber and filler weight about 1 to about 10 parts glass fibers; about 2 to about 20 parts cellulose pulp; about 1 to about 20 parts fibrillated polyolefin fibers; about 50 to about 96 total parcs of at least one inorganic filler selected from the group consisting of paper filler clay, wollastonite, talc, calcium carbonate, mica, pyrophyllite, and diatomaceous earth; about 10 to about 40 parts add-on of a synthetic rubber binder; about 2 to about 40 parts add-on of a soluble salt selected from the group consisting of aluminum salts, ferric salts and stannic salts, and a sufficient amount of an alkaline hydroxide to provide a furnish pH within the range of from about 6 to about 10, said alkaline hydroxide serving to convert said soluble salt to a water insoluble hydroxide, said felt having a dir,lensional stability of +0.30% or less when subjected to the High Humidity Dimensional Stability Test conditions.

15. A beater saturated, water-laid, asbestos-free, rub-berized flooring felt which exhibits dimensional stability produced by removing water from an aqueous furnish composition comprising in parts by weight per 100 parts the total fiber and filler weight about 1 to about 10 parts glass fibers; about 2 to about 20 parts cellulose pulp; about 1 to about 20 parts fibrillated polyolefin fibers; about 50 to about 96 total parts of at least one inorganic filler selected from the group consisting of paper filler clay, wollastonite, talc, calcium carbonate, mica, pyrophyllite, and diatomaceous earth; about 10 to about 40 parts add-on of a synthetic rubber binder; about 2 to 40 parts add-on of a soluble salt selected d from the group consisting of aluminum salts, ferric salts and stannic salts, and a sufficient amount of an alkaline hydroxide to provide a furnish pH within the range of from about 6 to about 10, said alkaline hydroxide serving to convert said soluble salt to a water insoluble hydroxide, said felt having a dimensional stability of +0.20% or less when subjected to the High Humidity Dimensional Stability Test conditic

16. The beater saturated, water-laid, asbestos-free rub-berized flooring felt of claim 14 further containing about 0.02 to about 2 parts add-on of a papermaking wet strength resin.

17. The beater saturated, water-laid, asbestos-free rub-berized flooring felt of claim 15 further containing about 0.02 to about 2 parts add-on of a papermaking wet strength resin.

18. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 14 further containing about 0.02 to about 1.6 parts add-on of a latex antioxidant.

19. The beater saturated, water-laid, asbestos-free, rub-berized flooring felt of claim 15 further containing about 0.02 to about 1.6 parts add-on of a latex antioxidant.

20. A surface covering comprising the beater saturated, water-laid, asbestos-free, rubberized flooring felt of claim 1 and a decorative wear surface joined to said rubberized flooring felt.

21. A surface covering comprising the beater saturated, water-laid, asbestos-free, rubberized flooring felt of clairl 14 and a decorative wear surface joined to said rubberized flooring felt.

22. A surface covering comprising the beater saturated, water-laid, asbestos-free, rubberized flooring felt of claim 15 and a decorative wear surface joined to said rubberized flooring felt.

23. A surface covering comprising the beater saturated, water-laid, asbestos-free, rubberized flooring felt of claim 16 or 17 and a decorative wear surface joined to said rubberized flooring felt.

24. A surface covering comprising the beater saturated, water-laid, asbestos-free, rubberized flooring felt of claim 17 or 19 and a decorative wear surface joined to said rubberized flooring felt.