DE2109047A1 - Process for improving the electrical conductivity of paper - Google Patents

Description

Folder 22499 - Dr ₀ K / biOase D, 22555

IMPERIAL CHEMICAL INDUSTRIES LIMITBD, London S. Vi- 1, Greater Britain

"Procedure aiar improvement of the electrical conductivity of paper "

Priorities: February 25, 1970 - Great Britain and

The invention relates to a method for the treatment of paper and more particularly to a method czar Verbesserang the electrical conductivity of paper ₀

Bs is already known, paper for various copier « to make processes suitable by having that paper treated with materials that improve electrical conductivity.

The invention relates to a method of improvement the electrical conductivity of paper, which is carried out by touching at least one surface of the

109840/1523

Papers apply an aqueous solution of a polymer or mixed polymer, which is repeated in the molecule Units of the formula

-CH ₉ - CR- .1 C

COOAN ^ X (I)

contains. where E is hydrogen or methyl, R is

2 3

Methyl or ethyl, R wad Br independently represent methyl or ethyl or together represent a group of the formula -CH ₂ CH ₂ OCH ₂ CH ₂ - or - (GH ₂ ) _n ~ (in which η 4t 5 or 6 means), A stands for alkylene or substituted alkylene and X ~ stands for a chloride or acetate ion, the polymer or copolymer having an average molecular weight in the range from 5000 to 2,000,000 »

Prevented the polymer or mixed polymer «in molecular weight from 10,000 to 500,000 »

An example of © in alkylene radical, which in JOrmel I by A is represented is ethylene, substituted alkylene radicals are e.g. hydroxysubstituiertθ alkylene radicals, such as ζ, Β, 2-Hydroxytrimethyls & o

The polymers or copolymers used in the erfindungegesaässen methods can be prepared by a catalyzed polymer radikaliech! Satiob a monomer of formula CH ^ CRCOQaSr RR .X ~ _r wherein optionally another vinyl monomer iat present "or free radical catalyzed by a

1098A0 / 1S23

lysed polymerization of a monomer of the formula CfH ₂ -CRCOOAHa ¹ R ² , with a further vinyl monomer optionally being present, followed by quaternizing the polymer or mixed polymer with a suitable quaternizing agent »

Copolymers suitable for use according to the invention preferably contain at least 15% by weight of the formula I ₀ comonomers of the vinyl series which can be used in the production of the copolymers are i ZoBo: styrene. Methyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate, ethylhexyl acrylate, acrylonitrile vinyl toluene, vinyl acetate, ß-ethoxyethyl methacrylate, ß-hydroxyethyl methacrylate, ethylene glycol dimethacrylate, acrylamide, diacetone acrylamide, ethylene, propzolene and divinylbenzole.

If in the mixed polymer as a comonoe »is used in such, that forms a water-insoluble polymer, then the portion of the comonomer be such that the copolymers are water-soluble. ,

It has unexpectedly been found that copolymers "" which contain a comparatively high proportion of non-quaternary units can increase the conductivity of a paper Ib substantially as effectively as a quaternary hoopolyer. In this regard particularly useful non-quaternary units are those obtained by using vinyl styrene, vinyl toluene, 2-ethylhexyl acrylate and methyl methacrylate = copolymers containing 15 to 80 percent by weight units from Porciel J. are both effective and economically attractive

109840/1523 b * d o «e.NAL

In addition to the economic advantages of using of a cheap non-ferrous quaternary comonomer there is another and unexpected benefit as a result, the ability to withstand solvents is improved «The steadfastness against Solvent is a measure of the ability of the treated paper to prevent the penetration of organic substances To effect solvents in the paper. A good resistance against solvents is in a commercially available one Electrofax base paper required, including penetration a photoconductive one made up in a solvent Means to prevent in the electrically conductive base paper

The solution dee polymer or mixed polymer can be deposited on that paper by any suitably bulky methods, for example duroh coating, dipping, spreading or impregnating _n The polymer or copolymer may be applied from an aqueous solution or an aqueous composition containing the polymer or copolymer together with contains one or more further additives that improve the application properties or the properties of the finished paper. Suitable additives are, for example, starch, water-soluble cellulose derivatives, polyvinyl alcohol, calcium carbonate and pigments. The amount of polymer or mixed polymer to be applied to achieve the desired electrically conductive properties can easily be determined by experiment *,

The paper treated by the method according to the invention is particularly suitable as a base paper for electrographic ^ To press.

10S840 / 1523

The invention is illustrated in more detail by the following examples. All parts and percentages are expressed in weight ο

example 1

A sized, whitened chemical wood pulp paper with a weight of 70 g / m 2 is coated on one surface with a 3.7 # aqueous solution of poly (trimethyl-β-methacryloylozyäthyl-> α & 2moniumchlorid) _f which has an average molecular weight of 52,000, so the B. a coating weight of 1 g / m (based on dry polymer components) obtained permanent standing wirdo After a 48 hours in a room with a sirkulierenden atmosphere of 20 ⁰ C and 20% relative humidity, the "surface resistance at a voltage of 500 V DC between two Brass electrodes of 25 χ 25 »measured, which are spaced on the treated surface of the paper by la

25 mm are arranged. The resistance will be 3.9 χ 10 Obs found"

For comparison, one is untreated paper and one in the same Same as above but using Calgon 26t coated paper (a commercial product) Calgon is a trademark of Calgon Corp.) using resistors from 3 χ 10 0hm or “6x10 0hm” can be measured

Example 2

The surface resistances of a paper which has been coated and tested as in Example 1 are shown in FIG given in the following table.

109840/1523

polymer

IDureh-Sßchnittl. ! Molecular weight

Lining weight

Surface resistance

etand (ohm)

Mixed polymer from equal amounts of trimethyl-ß ~ * methacryloyloxyäthylammoni tunchlor id. xxnä styrene

Poly (diethyl-methyl-ßmethacryloyloxyäthylaaanoniuaacetat)

Poly (methyl- Q- ethacryloyloxyethyl-pyrrolidinium chloride)

Poly (me thy 1 -beta -me thacryl oyloxyäthyl-piperidiniiHa-

chloride)

Poly (diethyl-methyl-ßmethacryloyloxyäthyl " ammonium chloride)

Poly (methyl-iS-methacrylic 1-oyloxyethyl -morpholinium chloride)

oa, 150,000

162,000

138 0OO

400,000

42,000

1
2

9.0 χ 10 "1.7 ι 10 ^ö

.8th

17 χ 10 ⁽

2.3 χ 10 ⁸ _R 0.44 x

28 χ 10 9.3 x 10 '53 χ ld

Example 3

The surface resistances at 20 % relative humidity of a paper, since it is coated with 1 g / m 2 of the most varied of hisehpolymers and a homopolymer, are given in the following table for comparison.

109840/1523

Mixed polymer nicat- CH, MoI- By" Upper io ^e Quaternary unit quaternary I ³ Ver cut ¹⁰ i unit -CH ₂ -C- hold. liches 10
10 ° I.
COQCH- the Molektt- area- • Homopolymer not- largewo resist. Cl " quatoE. (Ote] tci -CHCHp- 50:50 32,000 10 ⁸ -CH ₀ -C (OH-) - 40:60 1 + O 30 »70
25 * 75 5.9 x COOCH ₂ CH ₂ NMe- 4.7 χ Cl 50 * 50 47000 7.1 x
20 χ io ^a 40:60 30:70 10.5x 7, Ox tO, 5x -CH ₂ -C (CH,) -
I + untreated paper 5.5 x 300Ox

Example 4-

Dae prior Hold-Property Assets against Lösungsaiittel is determined that Z ιοί einee Löeungsmittele containing the color material C. I. Solvent Red 24, surface on the treated "upper einee base paper are pipetted _o lol 5 secants the excess solvent with a blotter removed, and the average any ^> o of the Sadel holes

109840/1523

Each 6.45 cm is counted on the other side " The solvents used are toluene and ^M Isopar Gr" (Esao Petroleum Company).

All funds are applied in an amount of 1 g / m on paper of the same quality of 70 g / m ^ »

not- MoI- Thread holes .ie CO ^ Mixed polymer quaternary Relationship 6.45 Isopar Gf Quaternary © Sinheit unit never 0? Oluene CH ₅ 50:50 -OH ^ C - 40:60
30:70 0.2 COOCH ₃ 0.5 t, 7
1 -GH ₂ C (CH ₅ ) - -CHCHp- 50:50 1.7
1 COOOH ₂ CH ₂ HMe ₅ 40:60 9 _? 5 O $ 30 70 6th 4th Me_Cl ~ homopolymer 4th 18th Poly (vinylbenzyl ~ triraethyl ™ ammonium 20th 3 -CH ₀ C (CH-) 00OGH ₀ CH ₀ chloride) 5 15th 14th

The foreword poly (viaylbenzyl-trimethyl-aaimonium chloride) igt a commercially available product, which is used as an eleJctriechleiteaides Resin for paper is sold and is included for comparison-

BAD OB) G (NAL

109840/1523

Example 5

Its range of interpolymers, which 57

Formula -CH ₂ C (CR ₅ ) - and 43 ¹

Units of one nothing

Cl

contains quaternary comonoxaer derived units will applied to paper in an amount of 1 g / m 2, and the surface resistance is at 20% relative humidity and 25 ° C; using 500 V direct current, which are applied over the ring-shaped gap between two concentric electrodes with 5 or »7 ca Burehmeeaer (British Standard 903). The results obtained are given in the table below

Non-quaterary B.
Comonomer average
liches mole
gross weight Surface a-
resisted
(0hm) Styrene
Vinyl toluene
2-ethylhexyl aerylate
Methyl methacrylate
Diacetone acrylamide
Butyl acrylate
Aorylonitrile
Ethyl aorylate approx _n 20,000
25,000
20 200
approx _o 20,000
23 800
20,000 1.4 χ 10 ⁹
T, 7 χ 10 ⁹
2.9 x 10 ⁹
4.8 χ 10 ⁹
1.6 10 ¹⁰
3.3 x 10 ¹⁰
1.1 χ 10 ¹¹
3.5 x 10 ¹¹ treated paper 2.9 x to ¹²

Example 6

Eb becomes a starch solution of 60 parts of cationic starch and 60 parts of water. 280 parts of boiling water

109840/1523

are sugesetgt, and the mixture is 15 minutes at 90 ° C touched. To 90 parts of the cooled starch r- ^ become 22.4 parts of a 36% aqueous solution. ■ Mixed polymer from 40 mol # trimethyl-2-methacryloyioxyäthyl-aamoniumchlorid and 60 Μο1- # styrene added »Another 22.6 parts of water are added, and 6. the mixture is stirred, leaving a pale colored solution due to the starch is slightly cloudy.

D & a coating mixture is applied to each side of the paper in an amount that a coating weight of 1.5 g / m DAEs on each side is obtained _o The Oberflächenwideretand is the electrode described in Example 5 at 20 # relative humidity and 25 ⁰ C using measured

The treated paper has a surface resistance of 4.1 10 ohms, while untreated paper has a surface resistance of 2.7 x 10 ¹² ohms. .."is"

Claims;

109840/1523

Claims (1)

PATENY AWARDS Process for improving the electrical conductivity of paper, characterized in that on at least one surface of the paper applies an aqueous solution of a polymer or mixed polymer which is in the Molecule of repeating units of the formula 2-ca- ^fi where R is hydrogen or methyl, R is methyl or ethyl, E and R ^ independently of one another are methyl or ethyl or together represent groups of the formula - CH ₂ CH ₂ OGH ₂ CH ₂ - or ~ (CH ₂ ) n- (where η is 4, 5 or 6), A stands for alkylene or substituted alkylene and X ~ stands for a chloride or acetate ion, the polymer or mixed polymer having an average molecular weight in the range from 5000 to 2,000,000, | 2, method according to claim 1, characterized in that the polymer or copolymer has an average molecular weight of 10,000 to 500,000 " 5, method according to claim 1 or 2, characterized in that that A stands for ethylene., 4. The method according to any one of the preceding claims, characterized in that a copolymer is used, 109840/1523 ^{mD 0WGlNAL} - 12 which. at least 15 wt _o -% of units of the formula 12 3 wherein R, R, R, R, A and X are those given in claim 1 W have meanings, the remainder of the mixed polymer consists of units derived from another vinyl monomer, 5ο method according to claim 4 »characterized in that that the other vinyl monomer consists of styrene, vinyl toluene, 2-ethylhexyl acrylate or methyl methacrylate « 6ο method according to claim 5, characterized in that that the copolymer 15 to 80 wt .- ^ t units of the formula COOAH X 12 3 - contains, in which R, R, R, R, A and X have the meanings given in claim 1 «, PATWfTMMMUI 1098AQ / 1523