GB1576310A - Creation of Inventions and Patents with Artificial Intelligence

GB1576310A – Composite sheet materials comprising resin-impregnated supporting materials
– Google Patents

GB1576310A – Composite sheet materials comprising resin-impregnated supporting materials
– Google Patents
Composite sheet materials comprising resin-impregnated supporting materials

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Publication number
GB1576310A

GB1576310A
GB33700/76A
GB3370076A
GB1576310A
GB 1576310 A
GB1576310 A
GB 1576310A
GB 33700/76 A
GB33700/76 A
GB 33700/76A
GB 3370076 A
GB3370076 A
GB 3370076A
GB 1576310 A
GB1576310 A
GB 1576310A
Authority
GB
United Kingdom
Prior art keywords
range
resin
liquid composition
dispersion
acrylate resin
Prior art date
1975-12-24
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)

Expired

Application number
GB33700/76A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)

HOECHST HOLLAND NV

Original Assignee
HOECHST HOLLAND NV
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
1975-12-24
Filing date
1976-12-23
Publication date
1980-10-08

1976-12-23
Application filed by HOECHST HOLLAND NV
filed
Critical
HOECHST HOLLAND NV

1980-10-08
Publication of GB1576310A
publication
Critical
patent/GB1576310A/en

Status
Expired
legal-status
Critical
Current

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Classifications

D—TEXTILES; PAPER

D21—PAPER-MAKING; PRODUCTION OF CELLULOSE

D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR

D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution

D21H17/20—Macromolecular organic compounds

D21H17/33—Synthetic macromolecular compounds

D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds

D21H17/37—Polymers of unsaturated acids or derivatives thereof, e.g. polyacrylates

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B21/00—Layered products comprising a layer of wood, e.g. wood board, veneer, wood particle board

B32B21/04—Layered products comprising a layer of wood, e.g. wood board, veneer, wood particle board comprising wood as the main or only constituent of a layer, which is next to another layer of the same or of a different material

B32B21/06—Layered products comprising a layer of wood, e.g. wood board, veneer, wood particle board comprising wood as the main or only constituent of a layer, which is next to another layer of the same or of a different material of paper or cardboard

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B13/00—Layered products comprising a a layer of water-setting substance, e.g. concrete, plaster, asbestos cement, or like builders’ material

B32B13/04—Layered products comprising a a layer of water-setting substance, e.g. concrete, plaster, asbestos cement, or like builders’ material comprising such water setting substance as the main or only constituent of a layer, which is next to another layer of the same or of a different material

B32B13/08—Layered products comprising a a layer of water-setting substance, e.g. concrete, plaster, asbestos cement, or like builders’ material comprising such water setting substance as the main or only constituent of a layer, which is next to another layer of the same or of a different material of paper or cardboard

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B21/00—Layered products comprising a layer of wood, e.g. wood board, veneer, wood particle board

B32B21/02—Layered products comprising a layer of wood, e.g. wood board, veneer, wood particle board the layer being formed of fibres, chips, or particles, e.g. MDF, HDF, OSB, chipboard, particle board, hardboard

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B29/00—Layered products comprising a layer of paper or cardboard

B32B29/02—Layered products comprising a layer of paper or cardboard next to a fibrous or filamentary layer

D—TEXTILES; PAPER

D21—PAPER-MAKING; PRODUCTION OF CELLULOSE

D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution

D21H17/20—Macromolecular organic compounds

D21H17/33—Synthetic macromolecular compounds

D21H17/34—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds

D21H17/38—Synthetic macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds containing crosslinkable groups

D—TEXTILES; PAPER

D21—PAPER-MAKING; PRODUCTION OF CELLULOSE

D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution

D21H17/20—Macromolecular organic compounds

D21H17/33—Synthetic macromolecular compounds

D21H17/46—Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds

D21H17/47—Condensation polymers of aldehydes or ketones

D21H17/49—Condensation polymers of aldehydes or ketones with compounds containing hydrogen bound to nitrogen

D—TEXTILES; PAPER

D21—PAPER-MAKING; PRODUCTION OF CELLULOSE

D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution

D21H17/20—Macromolecular organic compounds

D21H17/33—Synthetic macromolecular compounds

D21H17/46—Synthetic macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds

D21H17/47—Condensation polymers of aldehydes or ketones

D21H17/49—Condensation polymers of aldehydes or ketones with compounds containing hydrogen bound to nitrogen

D21H17/51—Triazines, e.g. melamine

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B2260/00—Layered product comprising an impregnated, embedded, or bonded layer wherein the layer comprises an impregnation, embedding, or binder material

B32B2260/02—Composition of the impregnated, bonded or embedded layer

B32B2260/028—Paper layer

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B2260/00—Layered product comprising an impregnated, embedded, or bonded layer wherein the layer comprises an impregnation, embedding, or binder material

B32B2260/04—Impregnation, embedding, or binder material

B32B2260/046—Synthetic resin

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B2315/00—Other materials containing non-metallic inorganic compounds not provided for in groups B32B2311/00 – B32B2313/04

B32B2315/12—Asbestos

B—PERFORMING OPERATIONS; TRANSPORTING

B32—LAYERED PRODUCTS

B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM

B32B2317/00—Animal or vegetable based

B32B2317/12—Paper, e.g. cardboard

B32B2317/125—Paper, e.g. cardboard impregnated with thermosetting resin

D—TEXTILES; PAPER

D21—PAPER-MAKING; PRODUCTION OF CELLULOSE

D21H23/00—Processes or apparatus for adding material to the pulp or to the paper

D21H23/02—Processes or apparatus for adding material to the pulp or to the paper characterised by the manner in which substances are added

D21H23/22—Addition to the formed paper

D21H23/32—Addition to the formed paper by contacting paper with an excess of material, e.g. from a reservoir or in a manner necessitating removal of applied excess material from the paper

D21H23/42—Paper being at least partly surrounded by the material on both sides

Description

(54) IMPROVEMENTS IN OR RELATING TO COMPOSITE SHEET MATERIALS
COMPRISING RESIN-IMPREGNATED SUPPORTING MATERIALS
(71) We, HOECHST HOLLAND N.V., a limited liability company of 25, Sara
Burgerhartstraat, Amsterdam, the Netherlands, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement:
This invention relates to the preparation of composite sheet materials by consolidating an assembly of a supporting sheet and one or more layers of resin impregnated supporting material, such as paper or analogous material, thereby to improve the surface of the supporting sheet.
In accordance with one aspect of the present invention there is provided a method of preparing a composite sheet material, by consolidating an assembly of a supporting sheet and one or more layers of resin-impregnated supporting material, that is characterised by impregnating paper or analogous supporting material in a single bath with a liquid composition containing an aminoplast resin and an acrylate resin which are compatible with each other, the quantity of acrylate resin with respect to aminoplast resin in the liquid composition being in the range 1 to 9.0% by weight based on the total solids content.
The aminoplast resin and acrylate resin may each conveniently be in the form of a solution, e.g. an aqueous solution, or a dispersion, e.g. an aqueous dispersion. Preferably, an aqueous dispersion with an ionic, e.g. weakly anionic, surface-active substance is used. It is also possible to use dispersions with cationic or non-ionic surface-active substances, provided the composition is such that no flocculation occurs.
The constituents of the liquid composition are preferably selected bearing in mind the compatibility of the resins with each other and with the supporting material and the tendency of the resins to flocculate on drying, it being advantageous to use compositions with which no flocculation of the resins occurs on drying. In this connection, it should be noted that, particularly when the aminoplast resin is a malamine resin, these properties depend on the quantity of available water remaining after drying following impregnation. This quantity of water determines to a great extent the properties of the impregnated material prior to and during pressure to form a composite sheet, as will be discussed below, and hence affects the surface properties of the resulting product.
Thus, in one preferred embodiment the liquid composition comprises a melamine resin and an acrylate resin which is compatible with paper, the composition being such that no flocculation of the resins occurs on drying.
In another preferred embodiment of the invention, the liquid composition comprises an aqueous dispersion of an aminoplast and a solution of an acrylate resin.
The liquid composition may also comprise, for example, a dispersion of an acrylate resin in a solution of aminoplast resin, e.g. melamine resin. In this case, the properties of the resulting product are affected by the surface charge of the dispersion, the particle size and the ionic character of the aminoplast resin solution and any modifying agents, and these may be appropriately selected to give a product having suitable properties.
Preferably an aqueous dispersion with an ionic surface-active substance is used. In this case, the desired ionic character of the dispersion may be obtained by using appropriate mixtures of anionic and non-ionic surface-active substances during the preparation of the acrylate resin. Such dispersions result in the production of impregnated material with a surface that is smooth, highly lustrous and has appropriate optical properties.
It is found particularly advantageous to use a dispersion of an acrylate resin in which the dispersion has a viscosity in the range 20 to 45 cPs and a pH in the range 5 to 7, the acrylate resin having a hardness in the range 0.5 to 5 x 1010 dynes/cm2 at OOC and a particle size in the range 0.01 to 0.35 microns. It should, however, be noted that acrylate resin solutions are also very suitable.
Further, the liquid composition need not necessarily comprise wholly separate acrylate resin and aminoplast resin solutions or dispersions, and may instead comprise a polycondensate in which acrylate resin is partly condensed with melamine resin.
The aminoplast resin may conveniently comprise a melamine resin, e.g. a melamine/formaldehyde condensate that may be produced in conventional manner, i.e. by subjecting melamine and formaldehyde to condensation in an aqueous alkaline solution. In this case, the mol ratio of melamine to formaldehyde is generally in the range 1:1.5 to 1:3. The melamine in the condensate can be partly or entirely replaced by other amino compounds, such as dicyandiamide, benzoguanamine or acetoguanamine, the mol ratios and reaction conditions being adapted accordingly.
The acrylate resin conveniently comprises copolymers of esters of acrylic acid that are compatible with the aminoplast resin, suitable copolymerisates conveniently being diluted with and dispersed in water.
Preferably, use is made of a netting acrylate resin, that is, a resin that crosslinks upon heating, in order to impart improved chemical and ultraviolet resistance to the resulting impregnated supporting material and composite supporting sheet produced therefrom.
Further, it is found that thermoplastic acrylate resins with a great degree of hardness (measured according to DIN 53445) appear to be very efficient.
Preferably, the quantity of acrylate resin with respect to aminoplast resin in the liquid composition is in the range 3 to 7%by weight based on the total solids content, such quantities producing very good results. More preferably, the liquid composition contains 5 % by weight acrylate resin with respect to aminoplast resin, based on the total solids content.
The supporting material to be impregnated by the method of the invention may conveniently be, for example, phenolic resin impregnated kraft paper.
The impregnation may conveniently be effected with any suitable conventional impregnating apparatus equipped with suitable impregnating and metering systems, and thus avoids the need to use two separate impregnating baths, as is the case with certain known methods for preparing impregnated supporting material in which a layer of paper or paper-like material is, for example, first impregnated with an aminoplast resin, one side of the layer subsequently being impregnated with a copolymer of an ester of acrylic acid.
It is found that the impregnating step that characterises the method of the invention produces impregnated paper or similar material in which surprisingly, the acrylate resin and the aminoplast resin, particularly a melamine resin, are so distributed in the thickness of the material that there is uniform and linear gradation of composition in and on the paper, resulting in advantageous processing and production properties. This result is believed to be connected with the behaviour of the supporting material, which acts to regulate distribution of the acrylate resin and aminoplast resin within the thickness of the supporting material, resulting in the highest acrylate content being at the surface of the impregnated supporting material. This, perhaps, accounts for the fact that it is found that the surface of the impregnated product is smooth and, surprisingly, has the properties of an acrylate resin surface notwithstanding the small amount of acrylate resin in the impregnating composition.
These results compare favourably with impregnated materials produced in certain prior art processes in which the transition from aminoplast resin to acrylate resin in and on supporting material is not homogeneous, an asymmetrically built-up thermoplastic film being produced that has great variations in physical and thermal properties in a direction extending perpendicular to the surface of the supporting material. As a result, the adherence between the acrylate resin film and layer of supporting material is not optimal, with the consequence that the resulting film is liable to corrode or crack when stressed.
The consolidation of an assembly of supporting sheet and one or more layers of the resin-impregnated supporting material may be accomplished by the application of appropriately elevated temperatures and pressures to the assembly. Preferably, the assembly is subjected to appropriately elevated pressure at an appropriately elevated constant temperature to form the composite sheet.
It is found that the method of the invention enables production of a composite sheet with a surface layer that combines the advantageous properties of both the acrylate resin and aminoplast resin. being highly glossy owing to the presence of the acrylate resin, yet scratch resistant and chemically resistant owing to the presence of the aminoplast resin.
The supporting sheets used in the method of the invention may be boards such as chipboard, fibreboard and asbestos board bound by organic or inorganic binding agents, the resin-impregnated supporting material conveniently being film-like.
Composite sheets are preferably manufactured in this way by pressing the assembly, e.g. in a suitable press, at pressures in the range 10 to 30 kg/cmZ at a temperature in the range 1200C to 190″C for a time in the range 20 to 80 seconds, the liquid composition used for impregnating the supporting material being such that the resulting impregnated supporting material hardens under such conditions. More preferably, the combination is pressed at pressures in the range 15 to 25 kg/cm2 at a temperature in the range 1700C to 1900C for a time in the range 30 to 60 seconds,
A suitable latent hardener is conveniently added to the liquid composition or a component thereof, e.g. the aminoplast resin, such that the resulting material will harden in less than 60 seconds at a temperature not exceeding 140″C.
As mentioned above, when preparing a composite sheet by the method of the invention, the assembly is preferably subjected to an appropriately elevated pressure at an appropriately elevated constant temperature. This method thus compares favourably with certain prior art methods of preparing composite sheets in which, in order to obtain glossy surfaces on the resulting products, it was necessary to use a multi-stage pressing operation, a typical such method involving firstly pressing sheets in presses at 1500C for, e.g. 10 minutes at pressures ranging from 20 to 30 kg/cm2, and then subsequently cooling the presses to a temperature ranging from 40″C to 800C for further pressing. It is clear that such a multi-stage pressing operation is inconvenient and results in significant energy losses, disadvantages that are not encountered with the present invention.
The present invention also includes within its scope impregnated supporting materials and composite sheets prepared by the methods of the invention.
The present invention will be further illustrated by the following Examples.
Example I
A melamine resin solution comprising 47% by weight solids was mixed with an aqueous acrylate resin dispersion with a ionic surface-active substance, the dispersion containing 45% by weight solids. The constituents were mixed in such quantities that, calculated on the quantity of total solids, 5 %by weight of solid acrylate resin is present in the resulting mixture.
The pH of this mixture was adjusted to 9.2 by means of a dilute base or a dilute acid, as appropriate, and a latent hardener added so as to produce a liquid composition having a curing time in the range 20 to 50 seconds at a temperature of 140″C.
A paper band was impregnated in a bath of this liquid composition and subsequently dried to a volatile components content of 5.0%, resulting in production of impregnated supporting material in the form of a thermoplastic film.
This film was applied to a fibre sheet and pressed in a press for 30 seconds at a constant temperature on a thin smoothing sheet with a lustre rate of 100.
In this Example, three types of paper were used as supporting materials, so-called unipaper, a type of wood pulp paper; a similar decorative wood pulp paper and non-woven cotton fibre fleece. The lustre rate of the surface of each of the resulting composite sheets was measured and the results are shown in the following Table.
Example II
The procedure of Example I was repeated, except a pressing time of 50 seconds was used.
The lustre rates of the resulting products are shown in the Table.
Similar results are obtained by using a solution of a water-soluble acrylate resin instead of a dispersion.
Example III
The procedure of Example I was repeated, except a pressing time of 80 seconds was used.
The lustre rates of the resulting products are shown in the Table.
Example IV
The procedure of Examples I to III inclusive were repeated, using a liquid composition with an acrylate content of 2%, for pressing times of 30, 50 and 80 seconds. The results of lustre rate measurements at the various pressing times are indicated in the Table under IV-a,
IV-b and IV-c respectively.
Example V
Example I was repeated using a liquid composition containing no acrylate for pressing times of 30, 50 and 80 seconds. The results of lustre rate measurements at the various pressing times are indicated in the Table under V-a, V-b and V-c, and it can be seen that these procedures do not produce composite sheets with satisfactory lustre rates.
Example VI
The procedure according to Example I is repeated, but instead of using a separate acrylate resin dispersion or acrylate resin solution use is made of a polycondensate obtained by adding acrylate resin during the preparation of the melamine resin, so that the acrylate is partly condensed with the melamine resin. Results are equivalent to results of other examples in accordance with the invention.
TABLE
pressing Lustre rate
Example Acrylate time (“long” reflection – measurement K 45 ) (sec) Unipaper decorative non-woven
paper fleece
I 5 30 90 90 85
II 5 50 100 95 90
III 5 80 90 90 90
IV-a 2 30 40 40 40
IV-b 2 50 50 50 45
IV-c 2 80 60 55 55
V-a 0 30 20 20 20
V-b 0 50 30 25 20
V-c 0 80 40 35 25
Note:
When longer pressing times are used the measured lustre rate decreases owing to an increased surface activity of the pressed products.
WHAT WE CLAIM IS:
1. A method of preparing a composite sheet material by consolidating an assembly of a supporting sheet and one or more layers of resin-impregnated supporting material, characterised by impregnating paper or analogous supporting material in a single bath with a liquid composition containing an aminoplast resin and an acrylate resin which are compatible with each other. the quantity of acrylate resin with respect to aminoplast resin in the liquid composition being in the range 1 to 9.0% by weight based on the total solids content.
2. A method according to claim 1, wherein the liquid composition comprises a dispersion of an aminoplast resin.
3. A method according to claim 2, wherein the dispersion is an aqueous dispersion.
4. A method according to claim 2 or 3, wherein the dispersion includes an ionic surfaceactive substance.
5. A method according to claim 4, wherein the dispersion includes a weakly anionic surface-active substance.
6. A method according to claim 1, wherein the liquid composition comprises a solution of an aminoplast resin.
7. A method according to any one of the preceding claims, wherein the aminoplast resin comprises a melamine resin.
8. A method according to any one of the preceding claims, wherein the liquid composition comprises a dispersion of an acrylate resin.
9. A method according to claim 8, wherein said dispersion is an aqueous dispersion.
10. A method according to claim 9, wherein said dispersion includes an ionic surfaceactive substance.
11. A method according to claim 10, wherein said dispersion includes a weakly anionic surface-active substance.
12. A method according to any one of claims 8 to 11, wherein said dispersion has a viscosity in the range 20 to 45 cPs and a pH in the range 5 to 7, the acrylate resin having a hardness in the range 0.5 to 5 x 1010 dynes/ cm2 at 0 C and a particle size in the range 0.01 to 0.35 microns.
13. A method according to any one of claims 1 to 7, wherein the liquid composition comprises a solution of an acrylate resin.
14. A method according to claim 13, wherein said solution is an aqueous solution.
15. A method according to any one of the preceding claims, wherein the liquid composition comprises a melamine resin and an acrylate resin which is compatible with paper, the composition being such that no flocculation of the resins occurs on drying.
16. A method according to any one of the preceding claims, wherein the liquid composition comprises a netting acrylate resin.
17. A method according to any one of the preceding claims, wherein the liquid composi
**WARNING** end of DESC field may overlap start of CLMS **.

Claims (33)

**WARNING** start of CLMS field may overlap end of DESC **. TABLE pressing Lustre rate Example Acrylate time (“long” reflection – measurement K 45 ) (sec) Unipaper decorative non-woven paper fleece I 5 30 90 90 85 II 5 50 100 95 90 III 5 80 90 90 90 IV-a 2 30 40 40 40 IV-b 2 50 50 50 45 IV-c 2 80 60 55 55 V-a 0 30 20 20 20 V-b 0 50 30 25 20 V-c 0 80 40 35 25 Note: When longer pressing times are used the measured lustre rate decreases owing to an increased surface activity of the pressed products. WHAT WE CLAIM IS:

1. A method of preparing a composite sheet material by consolidating an assembly of a supporting sheet and one or more layers of resin-impregnated supporting material, characterised by impregnating paper or analogous supporting material in a single bath with a liquid composition containing an aminoplast resin and an acrylate resin which are compatible with each other. the quantity of acrylate resin with respect to aminoplast resin in the liquid composition being in the range 1 to 9.0% by weight based on the total solids content.

2. A method according to claim 1, wherein the liquid composition comprises a dispersion of an aminoplast resin.

3. A method according to claim 2, wherein the dispersion is an aqueous dispersion.

4. A method according to claim 2 or 3, wherein the dispersion includes an ionic surfaceactive substance.

5. A method according to claim 4, wherein the dispersion includes a weakly anionic surface-active substance.

6. A method according to claim 1, wherein the liquid composition comprises a solution of an aminoplast resin.

7. A method according to any one of the preceding claims, wherein the aminoplast resin comprises a melamine resin.

8. A method according to any one of the preceding claims, wherein the liquid composition comprises a dispersion of an acrylate resin.

9. A method according to claim 8, wherein said dispersion is an aqueous dispersion.

10. A method according to claim 9, wherein said dispersion includes an ionic surfaceactive substance.

11. A method according to claim 10, wherein said dispersion includes a weakly anionic surface-active substance.

12. A method according to any one of claims 8 to 11, wherein said dispersion has a viscosity in the range 20 to 45 cPs and a pH in the range 5 to 7, the acrylate resin having a hardness in the range 0.5 to 5 x 1010 dynes/ cm2 at 0 C and a particle size in the range 0.01 to 0.35 microns.

13. A method according to any one of claims 1 to 7, wherein the liquid composition comprises a solution of an acrylate resin.

14. A method according to claim 13, wherein said solution is an aqueous solution.

15. A method according to any one of the preceding claims, wherein the liquid composition comprises a melamine resin and an acrylate resin which is compatible with paper, the composition being such that no flocculation of the resins occurs on drying.

16. A method according to any one of the preceding claims, wherein the liquid composition comprises a netting acrylate resin.

17. A method according to any one of the preceding claims, wherein the liquid composi
tion contains a thermoplastic acrylate resin.

18. A method according to any one of the preceding claims, wherein the quantity of acrylate resin with respect to aminoplast resin in the liquid composition is in the range 3 to 7% by weight based on the total solids content.

19. A method according to claim 18, wherein the quantity of acrylate resin with respect to aminoplast resin in the liquid composition is 5%by weight based on the total solids content.

20. A method according to any one of the preceding claims, wherein the liquid composition comprises a polycondensate in which acrylate resin is partly condensed with melamine resin.

21. A method according to any one of the preceding claims, wherein the liquid composition is such that the resulting impregnated supporting material hardens when subjected to pressures in the range 10 to 30 kg/cm2 at a temperature in the range 1200C to 1900C for a time in the range 20 to 80 seconds.

22. A method according to claim 21, wherein the liquid composition is such that the resultingimprenated supporting material hardens when subjected to pressures in the range 15 to 25 kg/cm at a temperature in the range 170to 1900C for a time in the range 30 to 60 seconds.

23. A method according to any preceding claim, wherein said assembly is consolidated by being subjected to appropriately elevated pressure at an appropriately elevated constant temperature to form the composite sheet.

24. A method according to claim 23, wherein said assembly is pressed at pressures in the range 10 to 30 kg/cm at a temperature in the range 1200C to 1900C for a time in the range 20 to 80 seconds.

25. A method according to claim 24, wherein said assembly is pressed at pressures in the range 15 to 25 kg/cm2 at a temperature in the range 1700C to 1900C for a time in the range 30 to 60 seconds.

26. A method according to any preceding claim, wherein said supporting sheet comprises chipboard, fibreboard or asbestos board.

27. A method according to claim 1, substantially as described with reference to Example
I.

28. A method according to claim 1, substantially as described with reference to Example
II.

29. A method according to claim 1, substantially as described with reference to Example
III.

30. A method according to claim 1, substantially as described with reference to Example
IV.

31. A method according to claim 1 substantially as described with reference to Example
VI.

32. An impregnated supporting material whenever prepared in the course of the method of any one of the preceding claims.

33. A composite sheet whenever prepared by the method of any one of claims 1 to 31.

GB33700/76A
1975-12-24
1976-12-23
Composite sheet materials comprising resin-impregnated supporting materials

Expired

GB1576310A
(en)

Applications Claiming Priority (1)

Application Number
Priority Date
Filing Date
Title

NL7515106.A

NL162155C
(en)

1975-12-24
1975-12-24

METHOD FOR MANUFACTURING AN IMPREGNATED FIBER FLUSH AND METHOD FOR MANUFACTURING A CARRIER PLATE

Publications (1)

Publication Number
Publication Date

GB1576310A
true

GB1576310A
(en)

1980-10-08

Family
ID=19825097
Family Applications (1)

Application Number
Title
Priority Date
Filing Date

GB33700/76A
Expired

GB1576310A
(en)

1975-12-24
1976-12-23
Composite sheet materials comprising resin-impregnated supporting materials

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Link

BE
(1)

BE849857A
(en)

DE
(1)

DE2657973A1
(en)

GB
(1)

GB1576310A
(en)

NL
(1)

NL162155C
(en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party

Publication number
Priority date
Publication date
Assignee
Title

DE2752159A1
(en)

1977-11-23
1979-06-07
Basf Ag

AGENT FOR SOAKING FIBERS CONTAINING CELLULOSIC

DE2903172A1
(en)

1979-01-27
1980-08-07
Roehm Gmbh

METHOD FOR PRODUCING PLASTIC-IMPREGNATED PAPERS, FIBER FLEECE AND THE LIKE

AT397634B
(en)

1991-09-30
1994-05-25
Isovolta

METHOD FOR PRODUCING A DRILL BASE AND A DRILL BASE PRODUCED BY THIS METHOD

DE19618681A1
(en)

1996-05-09
1997-11-13
Roehm Gmbh

Dispersions for paper impregnation containing water glass and / or dextrin

ITMI20082053A1
(en)

2008-11-19
2010-05-20
Eclissi Srl

HOT GLUEING OF PRINTS ON MDF PANELS (OR MDF TABLES) THROUGH PRESSES AND ADHESIVES

1975

1975-12-24
NL
NL7515106.A
patent/NL162155C/en
not_active
IP Right Cessation

1976

1976-12-21
DE
DE19762657973
patent/DE2657973A1/en
not_active
Withdrawn

1976-12-23
GB
GB33700/76A
patent/GB1576310A/en
not_active
Expired

1976-12-24
BE
BE173633A
patent/BE849857A/en
not_active
IP Right Cessation

Also Published As

Publication number
Publication date

NL162155C
(en)

1980-04-15

BE849857A
(en)

1977-06-24

DE2657973A1
(en)

1977-07-07

NL162155B
(en)

1979-11-15

NL7515106A
(en)

1977-06-28

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