DE1461260B2 - Recordable and photosensitive sheet-like recording material and process for its production - Google Patents

Description

contains. -.

2. Recording material according to claim 1, characterized in that the carrier is a polyethylene terephthalate film serves.

3. Recording material according to claims 1 and 2 ,, characterized in that the The coating also contains an acidic catalyst, preferably tin tetrachloride.

4. Process for the production of writable and photosensitive sheet-like recording material of a carrier and a cover, in particular according to Claims 1 to 3, characterized in that a suspension made of finely divided crystalline silica with a maximum particle size of less than 20 micrometers made in cellulose ester or in vinyl polymer and the suspension a partially hardened produced by the condensation of formaldehyde with urea, a diazine or a triazine Resin is mixed in, this suspension is applied to the carrier as a coating material, the coating cured for up to about 10 minutes at about 132 to 154 ° C and cured with a diazonium compound and a coupling component is sensitized.

5. The method according to claim 4, characterized in that the coating additionally a acid catalyst, preferably tin tetrachloride, is admixed.

The invention relates to a writable and photosensitive sheet-like recording material, consisting of a plastic film or a textile fabric as a carrier and a silica pigment containing coating.

There are various coated, film-like materials for graphic or photographic Purposes known. Few materials are suitable for both purposes. Sheets of paper become common glued and / or coated with inorganic opacifiers such as clay, kaolin or bentonite.

US Pat. No. 2,784,089 discloses photosensitive diazotype mixtures which contain, in aqueous dispersion, a photosensitive diazonium compound, an azo coupling component and iron-free colloidal silicon dioxide with particle sizes of 0.15 to 0.20 micrometers. These mixtures are applied to paper, whereby binders are not required.
Heretofore, many types of silica have been used to coat paper and other sheet material (U.S. Patent 2,999,016). Colloidal silica has been used in photographic recording materials (U.S. Patent 2,433,515). In other cases (U.S. Patent 2,784,089) the use of very finely divided silica of a particle size between 0.015 and 0.020 micrometers in conjunction with photographic diazotype layers has been suggested. US Pat. No. 2,662,013 describes the use of non-colloidal silica instead of the colloidal silica suggested in other references. This reference indicates that non-colloidal silica rubs off the support easily and that special procedures must be used to adequately bind the pigment. Subsequent investigations have shown that the proposed binders are usually not compatible with the sensitive photographic recording materials. Therefore, other binders, such as certain polyvinyl esters, may be preferred.

It has also been suggested that coating or glueing materials containing silica pigments to be applied to drawing paper using binders such as alkyd resins (U.S. Patent 2 999 016).

If a carrier is used to which some of the binders adhere poorly, e.g. B. Polyethylene terephthalate, the resin binder is mixed with a resin that adheres better to the support. Such a resin can be produced by condensation of formaldehyde with urea or with a diazine, such as 2,4,6-triaminopyrimidine, 2-mercapto-4,6-diaminopyrimidine or with similar compounds (U.S. Patent 2,211,710). It A triazine such as melamine or cyanuric trihydrazide or a similar compound can also be used (U.S. Patent 2,487,569).

No protection is sought for this measure, but only in connection with a label that can be written on and photosensitive recording material and a method for producing the same. U.S. Patent 2,662,013 discloses a process for making diazo type material Coating paper with a suspension of non-colloidal silica in an aqueous solution Solution of a film-forming, polymeric nitrogen-containing binder and impregnation of the coated Paper with a two-component diazotype mixture.

Many of the previously available sheet-form recording materials with a matt surface, at least one of the aforementioned requirements or properties is missing. Well-known, frequently used Pigments for sheet-like recording material are aluminum oxide and other metal oxides, silicates, Stearates, silica, diatomaceous earth, clays and starch. With all of these materials, the

Tendency to experience one or more of the following disadvantages:

1. After mechanical or manual erasing of pencil lines, "ghost images" remained erased lines back,

2. after erasing the surface became either shiny or whiter,

3. they yellowed with age or after repeated exposure to light,

4. They absorbed almost all radiation in the vicinity of the UV range, causing long exposure times were necessary in the production of diazotype copies.

The invention is based on the object of a writable and light-sensitive sheet-like Recording material using a plastic film or a textile fabric as a carrier to produce a matt white surface with excellent writability, good erasability as well as having high permeability to rays in the vicinity of the UV range.

This object is achieved according to the invention in that the coating

a) a cellulose ester or a vinyl polymer with the group CH ₂ = C as resin binder,

b) finely divided crystalline silica with a maximum particle size below 20 micrometers in such a quantity that the support surface is completely covered,

c) a partially hardened, by condensation of formaldehyde with urea, a diazine or resin made from a triazine,

d) additional pigments and

e) a diazonium compound, a coupling component and known for diazotype materials additions

contains.

The invention also relates to a method for producing writable and photosensitive sheet-like recording material from a support and a coating, which is characterized in that a suspension of finely divided crystalline silica with a maximum particle size of less than 20 micrometers is produced in cellulose ester or in vinyl polymer and the suspension is incorporated partially cured resin produced by condensation of formaldehyde with urea, a diazine or a triazine is admixed, this suspension is applied as a coating material to the carrier, the coating is ^{cured for up to about 10 minutes at about 132 to 154 0} C and with a diazonium compound and a Coupling component is sensitized.

An acidic catalyst, preferably tin tetrachloride, can also be added to the coating.

The finely divided crystalline silica in a binder containing coating provides excellent, matt white surfaces with good erasability and roughness. When using the appropriate There are no hairline cracks in the binder and the silica is difficult to rub off. The below Coating materials to be described in more detail can be made with diazo compounds and Coupling components are sensitized, which give good reproductions and excellent Properties regarding erasability and / or manually applied pencil changes or corrections to have.

Various types of finely divided crystalline silica, e.g. B. commercially available fine ground quartz and sand can be used. The use of finely divided crystalline silica with a maximum particle size below 20 micrometers represents an important characteristic of the Invention. By using such silica as a pigment in a corresponding binder, plastic films or textile weave receive excellent coatings that are used for drafts and pencil drawings, can.

For best results, the crystalline silica should preferably have a particle size under 10 microns. The optimal particle size is about 5 to 10 micrometers, where some smaller particles can also be used.

A crystalline silica of a particle size that can be passed through a sieve can also be used the clear mesh size of 150 micrometers passes through it. A 30 percent slurry of Sand in water or in an organic solvent, e.g. 2-methoxyethanol, acetone, methanol, Methyl isobutyl ketone or mixtures thereof that have been ground in a ball mill for 10 to 72 hours, gives optimal properties when used in intermediate layers for drawing purposes. The optimal one Particle size for drawing purposes depends to some extent on the intended use of the Type of pencils used and aesthetic values, e.g. the grip of the surface with different degrees of smoothness.

The pigment can be applied to various types of carrier.

In general, plastic films are most suitable for photographic purposes, e.g. plastic film made of cellulose acetate, cellulose acetate propionate, Polyamides, polyethylene, polyethylene terephthalate or polystyrene. As a textile fabric, a polyester-filled fiberglass fabric, polyester-filled cotton fabric, or any other commonly used in the manufacture of drawing materials used fabrics are used.

You can also use canvas and cover it with the silica-containing binder.

Any resin which is sufficiently flexible to permit handling of the finished product without cracking can be used as the binder. For this purpose, the. Use of the cellulose esters, e.g. B. cellulose acetate, or vinyl polymers with the group CH ₂ = C <C are preferred. These polyvinyl compounds can be homopolymers, e.g. polyvinyl acetate, polyvinyl butyral or polystyrene, or copolymers, e.g. of vinyl chloride and vinyl acetate (a mixture of 86% vinyl chloride and 14% vinyl acetate is particularly suitable), or copolymers of vinyl chloride, vinyl acetate and vinyl alcohol (a mixture of 91% Vinyl chloride, 3% vinyl acetate and 6% vinyl alcohol is very suitable), from vinyl butyral, vinyl alcohol and vinyl acetate (e.g. from 84.5% vinyl butyral

ral, 13% vinyl alcohol and 2.5% vinyl acetate) Vinyl acetate and crotonic acid, polyacrylic acid and polyacrylic acid esters, polymethacrylic acid or theirs Esters, from methacrylic acid and acrylic acid and their esters.

The polymer or copolymer used as a binder should be used in view of the intended Use carefully selected.

Mutually adhesive polymers can be partially polymerized, but should be prior to application not be fully polymerized. It is useful that the polymer is still reactive and not is fully cured so that it forms a firm bond with the carrier.

After applying the mixture of the binder and the crystalline silica to one Carriers with an adhesion-reducing surface can harden the formaldehyde resin, if this is used while the applied mixture is drying. To facilitate the complete hardening of this resin is preferably an acidic catalyst such as tin tetrachloride, aluminum sulfate, Methyl or ethyl phosphoric acid, salicylic acid, sulfosalicylic acid ^ ammonium chloride or Aluminum chloride is used. They are all known for use in the hardening of urea-formaldehyde condensates proposed acidic catalysts suitable.

During the production of the coating compound, the binder should be kept in a flexible form. To dissolve the binder, a solvent, in particular 2-methoxyethanol or methyl isobutyl ketone, used. The choice of solvent depends on the one used as the binder for the silica selected resin.

If a urea-formaldehyde condensate is used as a binder, it is hardened at a temperature between approximately 132 and 154 ° C for a period of up to about 10 minutes. The curing stage apparently takes place a reaction between the urine-formaldehyde condensate and the binding agent. So becomes a obtained very strong bond between the coating and the surface of the carrier.

Certain polymers which are emulsifiable or soluble in water can be used as binders will. For this purpose, some of the convertible acrylic polymers and are particularly advantageous - copolymers. The aqueous solutions, which are thermosetting, can also be used as binders for the pigment Acrylic resins can be used.

In addition to the finely divided crystalline silica, additional pigments can be used to increase the Whiteness of the coated support can be used, e.g. B. alumina or titanium dioxide. These pigments are supposed to can be used in such small amounts as to reduce the roughness and matte surface of the manufactured Do not affect the recording material.

To finish the recording material, the coated carrier is also coated with a diazonium compound and a coupling component sensitized. This mixture can contain the usual additives, like thiourea and an acidic compound like citric acid to avoid a premature coupling, the usual diazo and coupling components can be used will. Suitable diazonium compounds are, for. B. Ν, Ν-diethylaminobenzene diazonium chlorozincate and p-morpholinobenzene diazonium fluorate.

Suitable couplers are e.g. B. 2,3-dioxynaphthalene, resorcinol and m, m'-ethylenedioxide diphenol.

The examples explain how the experiment is carried out.

example 1

A coating compound was produced from the following components:

2-methoxyethanol 261

Vinyl acetate-crotonic acid mixed poly-

merisat 4500 g

Urea-formaldehyde resin 6750 g

Crystalline silica from ground sand with a particle size of
5 microns 3750 g

The mixture was mixed with 270 g of tin tetrachloride in 1500 ml of 2-methoxyethanol and applied to a polyethylene terephthalate film upset. The coated film was dried and the paint for 5 minutes cured at 149 ° C. The surface of the recording material thus produced had an unusual one good pencil receptivity, high smoothness, excellent erasability, high visual transparency and luminosity and showed no occurrence of "ghosting" of erased Lines and no shine.

Example 2

Example 1 was repeated with crystalline silica having a particle size of 10 micrometers. the The roughness of the surface obtained was somewhat increased.

Example 3

Example 1 was repeated, flint quartz was used as the pigment, which was 48 hours in one Ball mill had been ground.

Example 4

Example 1 was repeated using sand 150 micrometers in size as the pigment which had been ball milled for 48 hours.

Example 5

A polyethylene terephthalate film was made with coated with a coating compound of the following composition:

2-methoxyethanol, 261

Vinyl acetate-crotonic acid mixed poly-

merisat 4500 g

Urea-formaldehyde resin 6750 g

Crystalline silica with a particle size of 5 microns ... 2250 g

Silica gel powder (36 hours in

2-methoxyethanol ground) ... 1500g

Titanium dioxide pigment (36 hours in

Ground 2-methoxyethanol) ... 75 g

Tin tetrachloride in 750 ml

2-methoxyethanol 270 g

7 8

The paint was dried according to Example 1, methyl isobutyl ketone 85 ml

and hardened. 2-methoxyethanol 15 ml

This coat of paint provides a smooth, pencil-receptive vinyl chloride-vinyl acetate mixed poly-

Meable surface with very little surface polymer 15 g

glossy, medium matt effect and medium whiteness, medium 5. _Q ". . . '''''''"""'.'.''''' F T ^ ι ι · · · ι j -U * TJ a: ^ 48 Munden in a ball mill gelerer transparency and excellent eraser _mei ui _oinor c ~ "h λ " availability. Due to the content of titanium dioxide, the maniener band was 4 g

Transparency lower.

The coating obtained was smooth and, compared to the filled textile fabric, showed a significantly

Example 6 improved pencil absorbency and better ra-

controllability. There was only an insignificant increase

Example 5 was repeated, with a crystalline increase in the absorption of rays in the vicinity of the Silica with a size of 10 micrometers from the UV range was detected. Sand ground in a ball mill for 48 hours 15

or flint quartz was used. In this case example 10

approximately the same satisfactory results were obtained. A coating composition as shown below Composition was based on a cellulose

B is ρ ie 1 7 so acetate carrier applied, kneaded and dried:
A polyethylene terephthalate film was made with

a coating mass of the following composition 2-methoxyethanol .... 75 ml

coated: \ methanol '.'. '.'. '.'. '.'. '.'. 'Z'. '. 15 ml

".", .. ,,. ■ - ,, -, ^a5 cellulose acetate resin 3 g

2-methoxyethanol 351 _ "",. . _T. , .... ^B

.. 72 hours in a ball mill

Vinyl acetate-crotonic acid mixed polymer · ground sand 3 g

merisat 5400 g

Urea-formaldehyde resin ..... 8100 g 30 The paint showed excellent roughness and

Partly crystalline silica, ^very easy to erase, he had several corrections

size of 5 micrometers ... 2700 g ^{do a} " ^{f to the} same place, with each basket

correction, the line density of the pencil was preserved

Silica gel powder (36 hours _and no “ghost images” of the erased lines were ground on) 1800 g ₃₅ occurred.

Titanium dioxide (ground for 36 hours) 270 g Example 11

Tin tetrachloride in 1000 g _{The following} was applied to the base coat from Example 1

2-Methoxyatnanol 324 g _applied mixture and dried:

The paint was dried according to Example 1 with acetone 60 ml

and hardened. 2-methoxyethanol 30 ml

This paint provides a smooth pencil-absorbing formic acid 10 ml

multi-capable surface with very little surface area. Sulphosalicylic acid 25g

glossy, with a high matt effect and high whiteness, low 45 .. '

ger transparency and good erasability. By citric acid 2, Ug

the high content of titanium dioxide was the through-aluminum sulfate 2.0 g

eyesight greatly reduced. m, m'-ethylenedioxydiphenol 4 g

. p-morpholinobenzene diazonium

Examples 5 < > fluoborate 3 g

Example 7 was repeated, except that a crystalline one with such a recording material

Silica with a particle size of 10 micro- produced copy showed a high smoothness of the color image

meters from 48 hours ground in a ball mill, high copying speed, excellent

sand or flint quartz was used. In the roughness and erasability. Even after several

In this case, about the same were satisfactory - etchings did not become glossy, and so did it

the results achieved. no "ghosting" occurred. The good roughness

was also retained on the etched areas. the

Example 9 Transmittance to Visible and UV Light

60 was very high.

A coating composition of the type indicated below. When this mixture is applied to the in the

The same composition was applied to a base coat obtained with one of Examples 2 to 10

Base layer covered, starch-filled tex- den diazotype materials with similarly good properties

Tile fabric applied, kneaded and dried: shafts preserved.

409 516/35 ^r

Claims (1)

Patent claims: 1. Writable and photosensitive sheet-like recording material, consisting of a plastic film or a textile fabric as a carrier and one containing a silica pigment Cover, characterized in that the cover a) a cellulose ester or a vinyl polymer with the group CH., = C as resin binder, b) finely divided crystalline silica with a maximum particle size below 20 micrometers in such an amount that the support surface is completely covered, c) a partially hardened, by condensation of formaldehyde with urea, a Resin made from diazine or a triazine, d) additional pigments and e) a diazonium compound, a coupling component and for diazotype materials known additives