GB1562211A - Phenol-formaldehyde composition useful as a raw material for the preparation of phenolic resins - Google Patents

Description

(54) A PHENOL-FORMALDEHYDE COMPOSITION USEFUL AS A RAW MATERIAL FOR THE PREPARATION OF PHENOLIC RESINS (71) We, MATSUSHITA ELECTRIC WORKS LTD., of No. 1048, Oaza Kadoma, Kadoma-Shi, Osaka, Japan, a Japanese Company, 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 a phenol-formaldehyde composition useful as a raw material for the preparation of phenolic resins, and to a process for preparing a phenolic resin.

As examples of conventionally known compositions containing formaldehyde there are 37% formaldehyde (formalin), highly concentrated formalin, and solid paraformaldehyde.

Formalin contains 37 wt,% formaldehyde, and about 8-10 wt.% methanol, the balance being water. If the concentration of formaldehyde is low or the methanol content is high, the reaction rate with phenols is poor, whereby a long period of time is required for reaction. Further, about 63 wt.% of water and methanol does not participate in the reaction and is necesarily later removed.

Highly concentrated formalin contains 43A7 wt.% CH2O and the CH2O concentration is larger as compared with the above-described formalin. However, in order to prevent precipitation, methanol is further added so that the amount of methanol reaches 43-50 wt.%. As a result, reaction with phenols is further slowed, thereby prolonging the reaction time and no advantages are obtained.

Paraformaldehyde is a solid material containing above 80 wt.% of CH2O and below I,wt.% of methanol, and, in order to obtain such, an aqueous formaldehyde solution must be dehydrated. Since such dehydration is conducted at high temperatures, molecular weight increases, whereby extended periods of time are required to mix and dissolve the same with phenols. On the other hand, however, since the reaction-rate is high, the reaction system becomes heterogenous, whereby a gelled resin is apt to be obtained. Further, since paraformaldehyde is not in the form of a liquid, it is disadvantageous in charging it for reaction.

Further, with respect to the preparation of phenolic resins (e.g. resols or novolaks), phenols and a 37% aqueous solution of formaldehyde (formalin) have heretofore been mixed, heated and reacted in the presence of a catalyst, and the resins thus obtained have been dehydrated. However such processes involve the following disadvantages: (1) Since the concentration of a phenol-formaldehyde reaction system is low, conversion is low, and, as a result, a large amount of unreacted materials remain.

Therefore, the resins obtained are not sufficiently satisfactory in their properties, such as their heat resistance or curing rate.

(2) At dehydration, a large amount of water must be removed and production efficiency is poor. Further, the content of unreacted materials must be controlled in the dehydration step.

(3) In the case of transporting raw materials to the factory, phenols and formaldehyde must be separately and individually transported. Further, since formalin is formed in the form of an aqueous solution and then transported, reacted and dehydrated, such is very disadvantageous from the economical point of view.

On the other hand, in order to overcome the disadvantages of dehydration involved in conventional techniques, the direct reaction of phenols and formaldehyde polymers has been attempted, but, in such a case, the formaldehyde polymers do not easily dissolve in phenols, and in the case of trying to dissolve the same by heating, the thermal decomposition heat and the dissolution heat of formaldehyde and the reaction heat of phenols with formaldehyde are simultaneously generated, and, as a result, control of the reaction temperature is difficult, whereby the resins are gelated. Further, the properties of the resins obtained are poor in that gas generation at curing is large, heat resistance is poor, and removal from a mold at molding cannot be smoothly conducted.

Further, conventional resols are insoluble in water and are used in the form of varnish which is dissolved in organic solvents, such as methanol ethanol, benzene, toluene and xylene. However, organic solvents are generally inflammable and sometimes toxic. Thus, there are various disadvantages.

Heretofore, water-soluble resols have been prepared by reacting phenol and formalin in a highly alkaline environment (about pH 11) using caustic soda.

However, due to residual catalysts in the resin, properties such as the insulation resistance after boiling in water are remarkably poor, and as a result, it cannot be used as a resin for laminated boards and is merely used as an adhesive for plywood.

Further, in the case of preparing a resin for laminated plates, formalin is generally used within the pH range of 8 to 10, but, in such a case, a large amount of water is present in the reaction system, whereby the concentration of formaldehyde in the reaction system becomes low and the methylolation reaction is slow.

Therefore, in order to increase the conversion of formaldehyde to above 65% (in case of it being below 65%, unreacted materials increase and yield is poor), a long reaction time is required, and since methylolation proceeds during such a period of time, the resols obtained have a wide molecular weight distribution, i.e., have a large amount of methylolated polynuclear compounds. Therefore, resols having low affinity with water i.e., low water-miscibility, are merely obtained and it is difficult to form water-soluble resols.

For this reason, in the case of using resols for laminated plates as a varnish, where they are diluted using only water to adjust the viscosity thereof, the varnish becomes turbid whereby uniform varnishes cannot be obtained. Therefore, it is unavoidable to use organic solvents such as methanol. Organic solvents are removed by evaporation in a drying step after an immersion step, but such is not preferred from the viewpoint of costs of venting trea'tment or the like. Further, there is the danger of explosion in the drying step.

Thus, if resols could be water-solubilized, it can be expected that varnishes in which water is used as a solvent could be obtained, it would not be necessary to use expensive organic solvent, there would be no danger of explosion and production capability could be increased by using elevated drying temperatures.

On the other hand, it has been considered to increase reaction rate using paraformaldehyde having a purity of above 80%. In such a case, since methylolation is very vigorous in the reaction in the presence of an alkali catalyst (pH above 8.0), it is impossible to produce stable resols because it is difficult to control the reaction temperature, side-reaction occur, or bumping or gelation is caused.

An object of the present invention is to obviate or mitigate the above disadvantages.

According to one aspect of the present invention, there is provided a composition comprising one or more phenols and from 0.5 to 5 moles of formaldehyde per mole of said phenol or phenols, said composition having been formed by dissolving the formaldehyde in gaseous form in at least part of said one or more phenols and in the absence of any catalyst for the reaction of a phenol with formaldehyde.

According to another aspect of the present invention there is provided a process for preparing a phenolic resin by reacting one or more phenols with formaldehyde in the presence of an effective catalyst for the reaction, wherein there is employed a composition comprising one or more phenols and not more than 6 moles of formaldehyde per mole of said one or more phenols as a starting material, said composition having been prepared by dissolving gaseous formaldehyde in at least part of said one or more phenols and in the absence of any catalyst for the reaction of a phenol with formaldehyde.

Where the composition according to the present invention is used for the preparation of phenolic resins, the following characteristics can be obtained.

(1) The transportation cost of raw materials is extremely low.

(2) The composition can be subjected to reaction immediately after adding an appropriate catalyst, with or without controlling the component ratio of phenols and formaldehyde in the composition.

(3) Where the composition is subjected to reaction, reaction control is easy and conversion is high.

(4) Dehydration after reaction is unnecessary, or, if necessary, is easily conducted, and, as a result, production costs are low. Further, the reaction time is short.

(5) The composition has excellent storage stability.

The phenols which are used in the composition of the present invention are not specifically limited and one or more of any phenol (hereafter often merely referred to as "phenols") usable as a raw material for phenolic resins which are prepared by reaction with formaldehyde can be used. Examples of the phenols include phenol, cresols, xylenol, other alkyl phenols, such as ethyl phenol, propyl phenol, hexyl phenol, nonyl phenol or cashew nut shell liquid; alkenyl phenols, such as isopropenyl phenol; and polyhydric phenols, such as resorcin. Of these, phenols having a melting point of not higher than about 50"C are preferred in view of the subsequent treatment of absorbing formaldehyde. No limitation is imposed on the purity of the phenols so long as there is no problem in the preparation of phenolic resins. The phenols may contain any desired solvent. The phenols may be used singfy or as mixtures thereof.

Formaldehyde is generally obtained by the thermal decomposition of paraformaldehyde, the air-oxidation of methanol, the dehydrogenation of methanol, or the thermal decomposition of hemi-acetal. The manner of preparation of the formaldehyde is not limited and gaseous formaldehyde obtained in any manner can be utilized in the present invention. In general, no limitation is imposed on the purity of the formaldehyde if no problems are encountered in the preparation of phenolic resins. The formaldehyde may contain gases such as oxygen, nitrogen, hydrogen, carbon dioxide or carbon monoxide as impurities or dilute gases.

In general, though the invention is not to be limited to this, the composition of the present invention may be prepared by preparing phenols in a liquid state, introducing gaseous formaldehyde therein and absorbing and dissolving the same therein. There is, in principle, no limitation on the means, apparatus, manner or conditions used for the above operations.

There will now be described a preferred embodiment of introducing formaldehyde into phenols.

The phenols are prepared in liquid form and maintained at an appropriate temperature. Then, gaseous formaldehyde is introduced into the phenols so as to be absorbed and dissolved therein. In the case of absorbing and dissolving formaldehyde, 40 to 100"C is preferred as the temperature of the phenols, but it is desirable to operate at the low temperature side within the above range to an extent of not causing a polymerization of formaldehyde or a solidification of the phenols.

In such a composition, formaldehyde is present in an amount of not more than 6 moles, preferably from 0.5 to 5 moles, even more preferably 0.5 to 3 moles, per 1 mole of phenols.

The pressure of the absorption (or dissolution) can vary widely, but typically it is conducted at atmospheric pressure. The general rule, in this regard, is that no substantial benefits are achieved by using sub-atmospheric pressures for the absorption, in fact, absorption times are increased, and while absorption rate can often be increased by operation at super atmospheric pressures, generally the more complicated apparatus necessary to operate at super atmospheric pressure renders operation at super atmospheric pressure unprofitable.

The composition according to the present invention can contain water or water and methanol as optional components. The reason for the presence of such components is to obtain good storage stability of the composition. Specifically, the co-presence of water and methanol provides excellent storage stability. For example, the composition composed of phenols and formaldehyde becomes turbid at room temperature even though the turbidity may be removed by heating the composition to, for example, above 50"C, but a composition composed of phenols, formaldehyde and water or water and methanol is a transparent liquid even at room temperature.

A composition comprising phenols, formaldehyde and water can be obtained in the same manner as mentioned before. In such a case, water (which is one component of the preferred composition) may be mixed with phenols or be added to the composition obtained by dissolving the formaldehyde in the phenols. It is preferred that water be present in an amount of not more than 7 moles, more preferably from 0.05 to 4 moles, per 1 mole of phenols.

The composition comprising phenols, formaldehyde, water and methanol can be also obtained in the same manner as mentioned before. In such a case, methanol and water may be mixed previously with the phenols or may be added to the composition obtained by dissolving the gaseous formaldehyde in the phenols. It is preferred in such a composition that water be present in an amount of not more than 7 moles, more preferably from 0.05 to 4 moles, per 1 mole of phenols, and methanol be present in an amount of not more than 7 moles, more preferably from 0.05 to 4 moles, per 1 mole of phenols.

Phenolic resins including resols and novolaks can be prepared from the compositions according to the present invention in the same manner as is employed in the conventional reaction of phenols and formalin, i.e., by reacting the compositions in the presence of an appropriate catalyst. The foregoing compositions are especially useful as raw materials for the preparation of phenolic resins and bisphenol epoxy resins.

If the formaldehyde/pllels molar ratio is smaller than 0.5, cross-linking density during a curing stage is lacking whereby curing cannot be completely conducted while, on the contrary if the formaldehyde/phenols molar ratio exceeds 5, it is apt to cause gelation. A formaldehyde/phenols molar ratio within the range of from 0.5 to 3 is preferred in order to completely prevent gelation. Further, if the amount of other components is smaller than the lower limit thereof, the balance of the methylolation rate and the methyllation rate is lost and desired phenolic resins cannot be obtained, and if larger than the upper limit, the reaction proceeds slowly since methanol acts as a reaction retarder, whereby the reaction time becomes long.

With respect to the reaction conditions for forming such phenolic resins, and such is not limitative, it is preferred to conduct the reaction at temperatures of from 70 to 110"C. If the reaction temperature is lower than 70"C, the reaction proceeds too slow and is not practical, while if the reaction temperature is higher than 110"C, the reaction proceeds too vigorously. The reaction time is generally 60 to 300 hrs, though such varies depending upon the charging conditions. The reaction is conveniently performed at atmospheric pressure though sub- and super-atmospheric pressures can be utilized, if desired.

As a reaction catalyst, there can be used any acidic, neutral or alkaline catalyst as is widely and conventionally used in the preparation of phenolic resins.

Examples of acidic catalysts include hydrochloric acid, sulfuric acid, oxalic acid, phosphoric acid and p-toluenesulfonic acid. Examples of neutral catalysts include zinc acetate and manganese acetate. Examples of alkaline catalysts include caustic alkalis (e.g. caustic soda, caustic potash), sodium carbonate and organic amines.

The pH of reaction is dependant upon the kind of catalyst used, and in the case of using a neutral or acidic catalyst, the reaction is generally conducted at a pH of from 1 to 6, while in the case of using a neutral or alkaline catalyst, the reaction is generally conducted at a pH of from 7.5 to 11. The catalyst is used in an amount so as to adjust the pH of the reaction system to the desired range.

As is conventionally known, there is a close relationship between the formaldehyde/phenols molar ratio in the starting composition, the kind of catalyst used (i.e., the pH range) and the type of resin finally obtained. The same fact is encountered in the preparation of phenolic resins using the starting composition according to the present invention. That is to say, in the case of conducting the reaction of a composition having a formaldehyde/phenols molar ratio of not less than 1 in the presence of neutral or alkaline catalysts generally at a pH of from 7.5 to 11, resols (viscous liquid) are obtained. On the other hand, in the case of conducting the reaction of a composition having a formaldehyde/phenols molar ratio of not higher than 1 in the presence of neutral or acidic catalysts generally at a pH of from 1 to 6, novolaks (solid) are obtained.

Further, in the case of preparing water-soluble resols using the composition of the present invention, which is a very important feature of the present invention, reaction is preferably conducted in the presence of calcium hydroxide and/or barium hydroxide at a pH of from 7.5 to 9, more preferably from 8.0 to 8.5.

Laminates prepared using the resulting water-soluble resols thus obtained show excellent water-resistance, specifically, resistance to boiling water.

Before being subjected to reaction, the composition comprising formaldehyde and phenols used for the preparation of phenolic resins according to the present invention may be diluted with water to control the formaldehyde/phenols ratio to a suitable and desired ratio.

Further, after reaction, the reaction product may be neutralized with an acid or an alkali in a conventional manner.

Furthermore, after neutralization, desalting may be conducted in a conventional manner.

The phenolic resin obtained using the composition according to the present invention can be widely used as, for example, a varnish for the preparation of laminated plates, an adhesive for plywood or as a material for molding.

The following Examples are given to further illustrate the present invention in detail but the invention is not to be construed as being limited thereby.

PREPARATION EXAMPLE 1.

100 ml of liquid paraffin was charged into a 2 liter three-necked flask and nitrogen gas was passed therethrough at a feed rate of 0.5 1/min. while heating at l5l800C. A mixture of 90 g of paraformaldehyde powder and 150 g of liquid paraffin was gradually added dropwise to the flask over 45 min. Formaldehyde gas generated therein was taken into a 200 ml flask which contained 94 g of phenol at 95"C and was absorbed therein for 60 min. The weight increase of the composition obtained was 22 g, and, as result of CH2O analysis by the hydrochloric acidhydroxylamine method, the molar ratio of formaldehyde/phenol was 0.7:1.

The composition obtained was allowed to stand for 7 days at room temperature; the composition remained homogeneous and no change was observed with respect to the CH2O component.

PREPARATION EXAMPLE 2.

Formaldehyde gas generated in the same manner as in Example 1 was taken into a 200 ml flask which contained 94 g of phenol at 950C and absorbed therein for 150 min. During absorption, no specific vigorous heat absorption or generation was observed. The weight increase of the composition obtained was 61 g, and, as a result of CH2O analysis as in Example 1, the molar ratio of formaldehyde/phenol was 2.0:1.

The composition obtained was a homogeneous solution at temperatures above about 35"C and whitened at temperatures lower than about 35"C, but when heated to above 50"C, a uniform, transparent solution was obtained.

Further, the composition was allowed to stand for 7 days at room temperature, but no change of the components was observed.

PREPARATION EXAMPLE 3.

100 ml of liquid paraffin was charged into a 2 1 three-necked flask, and nitrogen gas was passed therethrough while heating at 150.-I 800C at a feed rate of 0.5 I/min. A mixture of 100 g of paraformaldehyde powder and 60 g of water was then gradually added dropwise to the flask over 120 min. Formaldehyde gas and steam generated therein were taken into a 200 ml flask which contained 94 g of phenol at 950C and was absorbed for 160 min.

The composition obtained contained 3.01 moles of formaldehyde and 3.3 moles water per mole of phenol.

The composition was allowed to stand for 3 days at room temperature and maintained its homogeneity; no change of the components was observed.

PREPARATION EXAMPLE 4.

A composition was obtained in the same manner as in Example 3 except that a mixture of 100 g of paraformaldehyde and 30 g of water was used, and absorption was conducted for 170 min.

The composition obtained contained 2.5 moles formaldehyde and 1.6 moles of water per mole of phenol.

The composition was allowed to stand for more than 2 days; it maintained its stability, and no change of the components was observed.

PREPARATION EXAMPLE 5.

Formaldehyde gas was generated in the same manner as in Example 3 and steam was mixed therewith to obtain a mixed gas of 80 wt.% CH2O and 20 wt.% H2O. The mixed gas was introduced into phenol for 170 min. and absorbed and dissolved in the same manner as in Preparation Example 3.

The composition obtained contained 4.5 moles of formaldehyde and 1.88 moles of water per mole of phenol.

The composition was stable over one night and one day, and no change of components was observed.

PREPARATION EXAMPLE 6.

Into a copper tube reactor (diameter: 55 mm) were supplied 1.2 kg/hr of methanol and 12.4 m3/hr of air (air/methanol ratio (I/g) = 10.3), and reaction was conducted at 3500C in the presence of 40 g of MoO3 catalyst to obtain a mixed gas of formaldehyde and water (62.5 wt.% CH2O and 37.5 wt.% H2O).

The mixed gas obtained was introduced into 94 g of phenol charged in a 200 ml flask (at 95"C) and absorbed therein for 170 min. During absorption, no specific rapid heat absorption or generation was observed.

The composition obtained contained 2.5 moles of formaldehyde and 2.5 moles of water per mole of phenol.

The composition was allowed to stand for more than one week at room temperature but no change occurred.

PREPARATION EXAMPLE 7.

A composition was obtained in the same manner as in Preparation Example 3 except that a mixture of 110 g of paraformaldehyde powder, 44 g of water and 22 g of methanol was gradually added thereto dropwise. The weight increase of the composition obtained was 158 g, and, as a result of CH2O analysis by the hydrochloric acid-hydroxylamine method, it was confirmed that 3.28 moles of formaldehyde, 0.69 mole of water and 2.1 moles of methanol per mole of phenol were present.

The composition obtained was allowed to stand for more than 4 days at room temperature, and no whitening and solidification occurred; further, no change of the components was observed.

PREPARATION EXAMPLE 8.

A composition was obtained in the same manner as in Preparation Example 7 except that 26 g of water was used. The weight increase of the composition obtained was 170 g. The composition had 3.5 moles of formaldehyde, 1.17 moles of water and 1.38 moles of methanol per mole of phenol.

The composition obtained was allowed to stand 3 days at room temperature; it maintained its stability and no change of the components was observed.

EXAMPLE 1.

Into a reaction vessel equipped with a stirrer, a reflux condenser and a thermometer were charged 474 parts by weight of a phenol-formaldehyde composition according to the present invention (formaldehyde/phenol = 2:1 (in molar ratio); water/phenol = 3.13:1 (in molar ratio)) and 26 parts by weight of phenol to adjust the formaldehyde/phenol molar ratio to 1.78:1. Calcium hydroxide (catalyst) was added thereto to adjust the pH of reaction system to 8.5.

Reaction was conducted at 1000C for 50 min. to obtain a resol resin.

The resin obtained was diluted with water and impregnated into a linter paper having a weight of 100 g/m2. Ten sheets of the impregnated papers (prepegs) were superposed and pressed at 150"C under 100 Kg/cm2 to obtain a laminate.

The laminate obtained was excellent in its resistance to boiling water and showed almost no weight change.

EXAMPLE 2.

The procedures of Example 1 were repeated in the same manner except that barium hydroxide was used instead of calcium hydroxide.

The laminate obtained was excellent in its resistance to boiling water and showed no weight change.

COMPARATIVE EXAMPLE 1.

188 parts by weight of phenol and 289 parts by weight of 37% formalin were charged into the same reaction vessel as was used in Example I to adjust the formaldehyde/phenol molar ratio to 1.78. Calcium hydroxide was added to adjust the pH to 8.5.

Reaction was conducted at 100"C for 120 min. The reaction mixture was then dehydrated at 600 mmHg for 60 min. to eliminate 130 parts by weight of a dehydrated waste solution to obtain a resin.

Using the resin, a laminate was prepared as in the same manner as in Example 1.

COMPARATIVE EXAMPLE 2.

94 parts by weight of phenol and 66.8 parts by weight of 80% paraformaldehyde were charged into the same reaction vessel as was used in Example 1 to adjust the formaldehyde/phenol molar ratio to 1.78. Barium hydroxide was added thereto to adjust the pH of the reaction system to 8.5.

Reaction was initiated at 1000C, but, after 10 min., gelation occurred due to rapid heat generation.

COMPARATIVE EXAMPLE 3.

216 g of m-cresol and 324 g of 37% formaldehyde (formalin) (formaldehyde/mcresol = 2 (in molar ratio), water/formaldehyde = 0.6 (in weight ratio)) were charged into the same reaction vessel as was used in Example 1 to control the formaldehyde/m-cresol molar ratio to 2.0. Then, sodium hydroxide was added thereto to adjust the pH of reaction system to 9.0.

Reaction was cohducted at 100C for 120 min. Then, the reaction mixture was dehydrated at 520 mmHg for 60 min. to eliminate 150 parts by weight of dehydrated waste solution to obtain a resin.

Using the resin obtained, a laminate was prepared in the same manner as in Example 1.

The results obtained in Examples 1 and 2 and Comparative Examples 1 to 3 are set forth in the following Table.

TABLE Comparative Comparative Comparative Example 1 Example 2 Example 1 Example 2 Example 3 Conversion of Phenol or m-Cresol (mol %) 80.3 81.2 78.5 - 80.4 Conversion of Formaldehyde (mol %) 80.0 82.2 70.6 - 78.0 Miscibility*1 190 220 41 - 0 Viscosity (cps) (at 30 C) 150 120 120 - 280 See Note *4 Properties of Laminate Resistance to Boiling Water*2 (hrs) > 18 > 18 5 - 9 Size Change*3 (%) Longitudinal Direction 0.13 0.20 0.62 - 0.68 Horizontal Direction 0.35 0.41 0.88 - 0.96 Notes: *1 : Amount of water (ml) at the time that water is added to 100 parts by weight of resin and turbidity appears (at 30 C).

*2 : Time (hrs) until swelling caused by immersing the laminate into boiling water.

*3 : According to JIS K-6903.

*4 : Measurement impossible due to occurrance of gelation in Comparative Example 2.

EXAMPLE 3.

Into the same reaction vessel as was used in Example I were charged 76.5 g of phenol and 132.1 g of a mixture of phenol, formaldehyde, methanol and water (formaldehyde/phenol molar ratio = 1.8:1: methanol/phenol molar ratio = 0.12:1; water/phenol molar ratio = 19.6:1) according to the present invention. Then, 0.6 g of (COOH)2 was added thereto and the mixture was heated to 98"C over about 40 min. while stirring, and then further stirred for 120 min. at 98"C. Thereafter, the reaction mixture was dehydrated at 520 mmHg for 75 min. to eliminate 52.2 g of a dehydrated waste solution and to obtain 153.5 g of a pale yellow resin.

Conversion of formaldehyde (0)) . 99 Conversion of phenol ( Ó) . 90 Softening point of resin obtained ("C) : 96.3 COMPARATIVE EXAMPLE 4.

Into the same reaction vessel as was used in Example 1 were charged 106 g of phenol and 74.3 g of 37% formalin. Then, 0.45 g of (COOH)2 was added thereto and reaction conducted at 98"C for 200 min.

The reaction mixture was dehydrated at 520 mmHg for 180 min. to eliminate 63 g of a dehyd

Claims (13)

Conversion of formaldehyde ( Ó) 98 Conversion of phenol (%) 90 Softening point of resin obtained ("C) : 98 WHAT WE CLAIM IS:

1. A process for preparing a phenolic resin by reacting one or more phenols with formaldehyde in the presence of an effective catalyst for the reaction, wherein there is employed a composition comprising one or more phenols and not more than 6 moles of formaldehyde per mole of said one or more phenols as a starting material, said composition having been prepared by dissolving gaseous formaldehyde in at least part of said one or more phenols and in the absence of any catalyst for the reaction of a phenol with formaldehyde.

2. A process as claimed in Claim 1, wherein the amount of said formaldehyde is from 0.5 to 5 moles per mole of said one or more phenols.

3. A process as claimed in Claim 1, wherein the amount of said formaldehyde is from 0.5 to 3 moles per mole of said one or more phenols.

4. A process as claimed in Claim 1, 2 or 3, wherein said composition further contains not more than 7 moles of water per mole of said one or more phenols.

5. A process as claimed in Claim 4, wherein the amount of said water is from 0.05 to 4 moles per mole of said one or more phenols.

6. A process as claimed in Claim 1, 2 or 3, wherein said composition further contains not more than 7 moles of water and not more than 7 moles of methanol per mole of said one or more phenols.

7. A process as claimed in Claim 6, wherein the amount of said water is from 0.05 to 4 moles per mole of said one or more phenols and the amount of said methanol is from 0.05 to 4 moles per mole of said one or more phenols.

8. A process as claimed in any preceding Claim, wherein said gaseous formaldehyde has been prepared by the air-oxidation of methanol.

9. A composition useful as a raw material for the preparation of a phenolic resin or a bisphenol epoxy resin comprising one ore more phenols and from 0.5 to 5 moles of formaldehyde per mole of said one or more phenols said composition having been prepared by dissolving the formaldehye in gaseous form in at least part of said one or more phenols and in the absence of any catalyst for the reaction of a phenol with formaldehyde.

10. A composition as claimed in Claim 9, further comprising from 0.05 to 4 moles of water per mole of said one or more phenols.

11. A composition as claimed in Claim 9, further comprising from 0.05 to 4 moles of water per mole of said one or more phenols and from 0.05 to 4 moles of methanol per mole of said one or more phenols.

12. A composition as claimed in Claim 9 substantially as hereinbefore described in any one of Preparation Examples 1 to 8.

13. A process of preparing a phenolic resin substantially as hereinbefore described in any one of Examples 1 to 3.