4576 4580.output

* GB784983 (A)

Description: GB784983 (A) ? 1957-10-23

Improvements in or relating to pumps, more particularly for lubricationsystems

Description of GB784983 (A)

PATENT SPECIFICATION 784983 & @ Date of Application and filing Complete Specification: July 4, 1956. No 20745/56. Complete Specification Published: Oct 23, 1957. Index at acceptance:-Class 102 ( 1), Al(A 1 B: A 2: B 7: B 8 A:Cl: C 3), A 2 A 2 A, A 3 A( 1 A: 3 B), A 4 (E 1: J: P: Q: Y). International Classification:-F 06 b. COMPLETE SPECIFICATION Improvements in or relating to Pumps, more particularly for Lubrication Systems We, TECALEMIT LIMITED, a British Company, of Great West Road, Brentford, 'Middlesex, do hereby declare the invention, (Communicated by Deutsche Tecalemnit G m b EI, a German Body Corporate of WindelsbleicheBielefeld, Germany), 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 pumps and has amongst its objects tile provision of an improved pump for delivering a liquid, and more particularly a lubricant, from a reservoir or container to a place or places of use The invention is more especially applicable to pumps for delivering oil under pressure into a central lubrication system in which the oil is conveyed to a number of bearings or other places of use The invention is, however, applicable to pumps for other purposes. With the usual types of pumps which draw liquid from a reservoir and deliver it to a place or places of use there is a risk that, if the pump is operated after the reservoir has been emptied, air will be drawn in, by the pump and delivered to the place of use This is often undesirable, particularly in the case of lubricant pumps which are used to supply oil to bearings or other points which have to be kept

lubricated It is, accordingly, one of the objects of this invention to provide a pump which includes means which will prevent it from being operated when there is an insufficient supply of the liquid in the reservoir. A further object of the invention is the provision of such a pump which is of compact and reliable construction. According to the invention a pump is provided for delivering a lubricant or other liquid to a place of use comprising a pump cylinder having a piston operating therein, means including an operating member for operating the piston and a reservoir supplylPoice 3 s 6 d l ing the liquid to the cylinder wherein locking means are provided responsive to the quantity of liquid in the reservoir for preventing operation of the pump when this quantity is less than a minimum value 50 Preferably the pump cylinder is arranged within the lower part lof the casing forming the reservoir and according to a preferred form of construction the pump cylinder and the body of the casing are cast integrally with 55 each other. In a preferred arrangement the locking means comprises a float which is movably mounted in the reservoir and a locking element which, when the float descends below 6) a predetermined level moves into a position in which it engages the piston to arrest the movement of the latter. For the better understanding of the invention, the same will now be more fully de 65 scribed, by way of example, with reference to the accompanying drawings. In the drawing: Figure 1 is an elevational view, partly broken-away and in section, showing a single 70 piston lubricating pump exemplifying the invention; Figure 2 is a vertical sectional view, to a larger scale, showing the lower part of the pump of Figure 1; 75 Figure 3 is a detail view in the form of a horizontal section showing a small part of the pump of Figures 1 and 2. Referring to the drawing, the pump comprises a casing 1 which is preferably formed 80 of cast iron and which includes a pair of lugs 2 by means of which the pump may be bolted or otherwise secured to a wall, bulkhead or other support. The casing 1 provides a reservoir chamber 85 3 for the oil and a cylinder 4 for the delivery pump The bottom of the reservoir 3 is arranged to slope downwardly towards a port (Figure 2) which opens into the cylinder 4 towards one end of the latter Below the 90 port 5 the cylinder 4 is formed with a drainage port 6 which is closed by means of a plug 7. Slidably mounted in the cylinder 4 is a piston 8 which is formed with an axial bore 9 At its inner end the bore 9 is formed with a shoulder 10 to provide an inner bore 11 of reduced diameter This bore 11 is

connected by means of an axial passage 12 with a vertical passage 13 drilled in the piston, which provides a fluid connection between the port 5 and the bore 11, as well as between the port and the drainage port 6. The end of the piston 8, which is cut away on each side as shown in Figure 3, forms a head 14 by which the piston is operated Arcuate grooves 15 of saw-tooth section are formed in the outer surface of the head 14 for a purpose to, be described. A packing ring 16 is fitted in a groove in the piston 8, within the cylinder 4, to prevent escape of oil between the piston and cylinder. Fitted in the bore 9 of the piston 8 is a guide member 17 having a bore 18 in which a valve element 19 is slidably mounted This element 19 is formed near its inner end with a groove 20 in which is fitted a washer 21 made of synthetic rubber or other suitable resilient material The edge of this washer 21 normally projects at an angle to the axis of the piston beyond the end of the valve element 19 so as to bear, by virtue of its natural resiliency, against the inner end of the bore 11 which forms a seat for the valve. The guide 17 is of square section having a diagonal corresponding to the diameter of the bore 9 It thus provides edge passages through which oil passing the valve element 19 can enter the cylinder The piston 8 is biassed to the left by means of a return spring 22 which is under compression between the guide member 17 and the body 23 of a non-return delivery valve, which is indicated generally by the reference 24 This body 23 is screwed into the end of the cylinder 4 and is provided with a sealing ring 25 to prevent the escape of oil. The body 23 is formed internally with a bore 26 the outer end portion 27 of which is of increased diameter and is screw-threaded to receiver a union, 28 This union serves for the attachment of a delivery pipe (not shown). A valve element 29 is slidably mounted in the bore 26 and is pressed by means of a spring 30 against a valve seat provided by a shoulder 31 formed in the body 23 near the inner end of the bore 26 The outer end of the spring 30 extends into a bore 32 in the union 28 and abuts against a shoulder at the end of this bore, The cylinder 4 is formed in its upper portion with a socket 35 the lower end of which opens by means of a port 36 into the end, of the cylinder 4 A spring controlled' pressure relief valve 37 is screwed into the socket 35, this valve being arranged to open when the delivery pressure exceeds a predetermined value. Oil escaping through the valve 37 is returned to the reservoir 3 through a pipe 38 the upper 70 open end of which is located beneath a transparent inspection dome or window 39 The sight of oil discharged from the pipe 38 shows that the pump is working.

The pump is operated by means of an oper 75 ating shaft 40 which is rotatably mounted in the end of the cylinder 4 and which carries a pump handle 41 The lower end of this handle is screwed and pinned into a split boss 42 which is clamped to the projecting end of the 80 shaft 40. The shaft 40 is formed with an eccentric cut-away groove 43 (Figure 3) leaving a reduced neck 44 of circular section which forms an operating cam or eccentric for the 85 piston 8, the head 14 of which piston engages in the groove 43 and' is pressed against the cam neck 44 by the spring 22 The engagement of the piston head 14 in the groove 43 between the main part of the shaft 40 and the 90 end part 45 thereof prevents turning of the piston in the cylinder. The reservoir 3 is closed by means of a cover 46 which is screwed or otherwise secured to the upper end of the casing 1, with the 95 interposition of a packing ring if necessary. The cover 46 is provided with a removable filler cap 47. Secured to the under side of the cover 46 by screws or other means, if desired with the 100 interposition of a suitable packing, is a filter 48, which may be of a wire mesh or other suitable type All oil introduced into the reservoir 3 must pass through this filter before it enters the port 5 of the pump 105 A transparent window 49 is provided in the side of the casing 1 to enable the level of the oil in the reservoir 3 to be seen when this level falls to a low value. The pump is provided with locking means 110 which are arranged to prevent the pump piston from being operated when the oil level falls below a minimum value This locking means comprises anil arm 51 which is pivotally mounted in the lower part of the reservoir 115 3 In the construction shown the arm 51 includes a pair of side flanges 52 'which extend on opposite sides of the upper part of the cylinder 4, to which they are pivoted at 53 The arm 51 carries a ball float 54 which is 120 secured in a recess 55 in the arm 51 by means of a resilient strip 56. The arm 51 also carries a downwardly-projecting locking tooth 57 the pointed end of which is adapted to engage in the groove 15 125 in the piston head 14 in order to lock the piston 8 in its right-hand position. The operation of the pump is as follows: Before use the reservoir 3 is filled with oil by removing the filler cap 47, which cap is 130 784,983 ders and pistons which could be arranged parallel to each other below the reservoir, from which they would deliver oil separately to individual bearings or other places of use.

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* GB784984 (A)

Description: GB784984 (A) ? 1957-10-23

Improvements relating to testing of compressors

Description of GB784984 (A)

PATENT SPECIFICATION Date of Application and filing Complete Specification: July 13, 1956. 784,984 No 21751/56. 71 t 1 ka 4} | Application made in United States of America on July 13, 1955. Complete Specification Published: Oct 23, 1957. Index at acceptance:-Class 8 ( 1), CX. International Classification:-G 011 COMPLETE SPECIFICATION Improvements relating to Testing of Compressors We, GENERAL ELECTRIC COMPANY, a Corporation of the State of New York, United States of America, having its office at Schenectady 5, State of New York, United States of America, 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 testing of compressors, particularly refrigerant compressors such as those which are employed in the refrigeration system for household refrigerators. Heretofore the factory testing in the final stages of the manufacture of household refrigerator compressors consisted in reading on a pressure gauge the maximum pressure developed by the compressor against a fixed restrictor The pressure reading was ordinarily taken when the pressure had become stabilized and as a net result the test for each compressor usually required from two to three minutes of

running time for each compressor This test was not only time consuming but also involved an accuracy problem in separating the acceptable compressors from the unacceptable since the usual pressure gauge capable of reading pressures from zero to 120 or more psi are normally calibrated in one pound increments and the spread of compressors in this range is normally small As a difference of as little as one psi in the maximum pressure developed by a given compressor may represent the difference between an acceptable compressor and one which is not acceptable, it is obvious that such test procedures and apparatus are not completely satisfactory. It is an object of the present invention to provide a method and apparatus for quickly and accurately testing a compressor The present invention is based in part on the discovery that the time required for a cornlPrice 3/6 l pressor to build up a given or predetermined discharge pressure against a fixed restrictor, which pressure is less than the maximum pressure developed by the compressor, is both a faster and more accurate measure 50 ment of the quality of the compressor than is the measure -of maximum pressure developed by the compressor. According to the invention there is provided compressor testing apparatus compris 55 ing means for initiating operation of a compressor with unrestricted flow of discharge gas, means for restricting discharge flow, timing means and means for starting the timing means concurrently with the opera 60 tion of the flow restricting means and for stopping the timing means when the compressor discharge pressure increases to a predetermined value. In a particular embodiment of the inven 65 tion, there is provided test equipment or apparatus comprising a fixed restrictor such as a capillary and means for connecting the restrictor to the compressor discharge conduit The connecting means or line has 70 ' connected thereto a normally closed pressure switch and a normally open solenoid operated relief valve which normally permits the compressor to operate against zero or a relatively low discharge back pressure When 75 the relief valve is closed, the compressor operates against the fixed restrictor or capillary and to provide means for measuring the time required for the compressor to build up a discharge pressure of a predeter 80 ( mined value after the valve is closed there is provided electrically-operated timing means, such as an electric clock, and an electric circuit for controlling the operation of the valve and for connecting the pressure 85 switch in series with the clock The closing of the switch in the electric circuit when the compressor is running serves to close the valve and start the clock Opening of the pressure switch when the compressure dis 90 784,984 charge increases toi a predetermined value deenergizes the timing means The running time of

the clock is a measure of the performance of the compressor. For a better understanding of the invention, reference may be had to the accompanying drawings in which Fig 1 is a somewhat schematic illustration of the apparatus employed in carrying out the present invention; and Fig 2 is a plot of representative pressure-time curves of different compressors operated on the test system of the present invention. The drawing shows a fixed restrictor or capillary 1 connected by a line 2 to the discharge conduit 3 of a hermetic compressor 4. During test of the compressor 4 the suction conduit 5 thereof is opened to the atmosphere Also connected to the line 2 between the connection thereof to the compressor 4 and the capillary 1, is a side line including a solenoid operated valve 6 which also opens to the atmosphere A pressure switch 7 is connected by a conduit 8 to the line 2 so that the operation of this switch is responsive to the pressures within the line 2. The pressure switch 7 is electrically connected in series with an electric timer or clock 9 and this circuit includes a manually operated switch 10 which also controls the circuit energizing the coil 11 effecting operation of the valve 6. In the use of this test apparatus, a compressor 4 is first connected to the line 2 and to a power source 12 by the closing of a switch 13 During this initial operation of the compressor the switch 10 is open so that the circuits including the solenoid 11 and the clock 9 are de-energized The air compressed by the compressor 4 and discharged through the discharge conduit 3 into the line 2 passes through the normally open valve 6 and is again discharged to the atmosphere so that the compressor is operating under a no-load condition, that is, with no restriction in the discharge line The pressure gauge switch 7 is set at zero pressure and the electric timer 9 is similarly set at zero The pressure gauge switch 7 includes electrical contacts (not shown) which are normally closed and which are opened when the pressure within the line 2 reaches a predetermined value. With the compressor 4 operating against zero back pressure in the discharge line 2, the switch 10 is closed thereby energizing the solenoid 11 and the timer 9 Upon closing of the solenoid valve 6, pressure is built up in the system against the flow restriction of the capillary 1, the flow through the capillary 1 being, of course, a function of the pressure within the line 2 When the pressure in the system reaches a predetermined value at which the pressure gauge switch 7 is set, this switch opens stopping the timer 9. The measure of the capacity of the compressor 4 is the time required for the compressor to build up the predetermined pressure against the restriction of the capillary 1.

The starting time of the compressor is not 70 involved as the compressor runs continuously Whenever it is found necessary, the test may be repeated immediately merely by opening the switch 10 thereby releasing the pressure within the line 2 and re-setting the 75 pressure gauge switch 7 and the timer 9 to zero settings. As has been previously indicated, the tests are conducted with the pressure gauge switch 7 set to de-energize the clock circuit 80 when the pressure within the line 2 reaches a value which is somewhat below the maximum pressure which can be developed by the compressor 4 For maximum accuracy, all of the lines or conduits such a 2 and 8 85 should be as short as possible so that the entire test system will have a relatively small volume as compared with the pumping rate of the compressor 4. For a further understanding of the advan 90 tages of the present invention reference should be had to Fig 2 of the drawing in which are plotted the pressuretime curves of three compressors A, B and C All three of these compressors were of the same type 95 and tested on the same test equipment and were designed to produce a maximum discharge pressure somewhat in excess of 120 psi. From a consideration of these curves it 100 will be noted that the pressure build up for all three compressors during the initial few seconds of the test was substantially constant or linear and at the rate of approximately pounds per second However after the 105 pressures reached about 60 psi the rate of build up of pressure against the fixed restrictor begins to decrease so that the slopes of the curves gradually decrease Also at this point, the curves tend to spread apart 110 and this spread is greater with regard to the time axis than the pressure axis For this reason and for the additional reason that a timer calibrated in seconds can be more easily and accurately read than a pressure 115 gauge calibrated in five pounds major increments and one pound minor increments, it will be seen that time is not only a more accurate but also a more significant factor than pressure in sorting compressor samples 120 In setting up the test, correlation tests are required to establish the reject level on a given test set up for a specific type of compressor, that is, the engineering specifications for capacity of a given type compressor 125 are established as a part of the machine design and compressors with these known values are used in determining the comparative time-cycle values as attained on a given test set up and arn used to establish the 130 754,984 proper reject levels. Preferably, the pressure gauge switch 7 is set to open the clock circuit at a pressure of from about 70 % to 90 % of the maximum pressure which can be developed in the test system by an average acceptable compressor.

For example in the diagram shown in Fig. 1, if the curve for compressor B be taken as the reject level curve for a type of compressor engineered to develop a maximum of about 125 psi against a given restrictor, the pressure gauge switch 7 may be set to open within a range of pressure of from about 85 to 112 psi For example if the switch is set to. open at 110 psi it will be noted that the reject level is approximately 15 seconds. Therefore any compressor which does not raise the pressure within the line 2 to this valve within 15 seconds is properly rejected. For example compressor A reaches pressure of 110 pounds within 12 seconds while compressor C which required 20 seconds does not meet the standard and is therefore rejected. These time differences of approximately three seconds between compressors A and B and five seconds between B and C can be accurately read from the usual electric timer However, it will be noted from Fig. 2 that the pressure differences between the three compressors at the 15 second mark, are relatively small particularly for the usual pressure gauge which measures pressure anywhere from zero to for example 150 psi. The present test method employing time as the significant test factor is particularly useful in testing and sorting compressors of the type mass produced for household refrigerators wherein economic considerations dictate the design of the refrigerating machine to closer specifications as affect the cost thereof One of the principal advantages of the present test method is in the separation of borderline compressors, that is compressors very close to the reject level and on either side thereof all of which will have approximately the same total pull down or maximum pull down if allowed to run long enough but which nevertheless would not give a satisfactory performance in a refrigerating system for a household refrigerator In many household refrigerators now on the market a compressor which requires too much time for proper pull down is not acceptable even though its maximum pull down is high For example in those systems. where defrosting of the evaporator is accomplished between each operating cycle of the refrigerating system, it is more desirable to employ a compressor which cycles frequently for short periods of time and which quickly establishes the desired pressure differentials within the system rather than one which requires a relatively long running time to 66 establish such pressures. While the test procedure has been described as including initial operation of the compressor against a zero or atmospheric back discharge pressure, significant and useable results can also be obtained in a 70 shorter time by initially connecting line 2 to a

pressure tank as a source of a constant pressure within the range of pressure where the time-pressure curves are substantially linear, closing the connection when the clock 75 is started and noting the time required for the compressor to build up the pressure in line 2 from the starting pressure to the predetermined test pressure.

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* GB784985 (A)

Description: GB784985 (A) ? 1957-10-23

Manufacture of organic phosphorus compounds

Description of GB784985 (A) Translate this text into Tooltip

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The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION Date of Application and filing Complete Specification: Oct 28, 1953. No 6973/57. Application made in United States of America on Oct 29, 1952. Application made in United States of America on April 15, 1953. Application made in United States of America on April 15, 1953. (Divided out of No 783,697) ' /T Complete Specification Published: Oct 23, 1957. Index at acceptance:-Class 2 ( 3), C( 1 B 7: 3 B).

International Classification:-CO 7 f. COMPLETE SPECIFICATION Manufacture of Organic Phosphorus Compounds We, FOOD MACHINERY AND CHEMICAL CORPORATION, a Corporation organised according to the laws of the State of New York, of 161, East 42nd Street, New York 17, State of New York, United States of America, 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 provides a process for the manufacture of monovinyl or E-substituted monovinyl esters of phosphoric acid or of a phosphonic acid, which esters correspond to the general formula: P-o-C C-R in which R 1 is a substituted or unsubstituted alkyl, aryl, alkoxy or aryloxy group, R 2 is a substituted or unsubstituted alloxy or aryloxy group, R, and R 4 are hydrogen or a substituted or unsubstituted alkyl, aryl, alkoxy or aryloxy group, wherein a tertiary phosphite or secondary phosphonite of the general formula: R,x /p-o-R R 2 in which R 1 and R 2 have the meanings given above, and R is a substituted or unsubstituted alkyl group, is reacted with an appropriate a monohalogenated aldehyde In this manner, for example, diethyl vinyl phosphate can be obtained by reacting triethyl phosphite with monochloracetaldehyde. Prior art attempts to prepare such compounds have involved reactions which are lPr/ce 3 s 6 d l relatively more complicated or more difficult to carry out than the process of the present invention For example, Schrader has described (PB 87,923 R, p 33, 1947) a process for the preparation of substituted vinyl phosphates involving the reaction of a chlorophosphate with a sodium enolate Such a process is handicapped by the fact that relatively few sodium enolates can be readily prepared. In United States Specification No. 2,557; 805, is described the preparation of diethyl vinyl phosphate by the dehydrohalogenation of a 2-halogen-ethyl phosphate. This reaction also presents certain difficulties. In the first place, the dehydrohalogenation cannot be carried out in alcohols, or even in inert solvents, with ordinary bases such as metallic hydroxides and alkoxides, due to solvolysis of the halogen-ethyl phosphate In the second place, attempts to carry out the dehydrohalogenation in inert solvents, such as ether, by special agents such as sodium hydride, give a very low yield of vinyl phosphate. The process of the present invention overcomes the foregoing and other disadvantages of the prior processes, involves the use of readily obtainable reactants, does not necessitate the use of a solvent

medium, and gives very satisfactory yields The products are useful and of interest as monomers and as chemical intermediates. -The tertiary phosphite or secondary phosphonite must contain at least one alkyl group which may be unsubstituted or substituted Alklyl groups of low molecular weight are preferred, such as ethyl or chlorethyl. The o -halogen atom of the aldehyde is removed during the reaction and the resulting vinyl ester does not contain halogen attached directly to the vinyl group Halogen may be present elsewhere in the molecule. Although the reaction is not understood with certainty, the probable reaction is as follows; 784,985 ' t, 11 _ 7 A, I I I #; P-O + o=c-C-R -o 4 + A ha I A'2 HI R 2 Sal A'2 The reaction may be carried out by the gradual addition of one of the reactants to the other at any suitable temperature, but the preferred range is approximately 25 C to C The temperature selected depends in part upon the activity of the halogen atom involved, and also to a lesser extent upon the activity of the phosphite or phosphonite used. In general, bromine compounds may be reacted at lower temperatures than in the case of chlorine compounds. Any suitable proportions of the two reactants may be used, but it is preferred to use equimolar proportions Although a solvent medium may be used, it is usually unnecessary and undesirable, and it is preferable to avoid the additional time and effort which is involved in removing a solvent medium from the product Either the monomeric or polymeric form of the carbonyl compound may be used. The following Examples and the Table illustrate the invention: EXAMPLE 1. Four moles ( 665 grams) of commercial triethyl phosphite were gradually added, while stirring, to 4 moles ( 314 grams) of monochloracetaldehyde over a period of 40 minutes with sufficient cooling to keep the temperature of the reaction mixture at 50-60 C The reactor was vented through a trap cooled by dry ice and trichlorethylene, in order to condense the by-product ethyl chloride When all the phosphite had been added the temperature of the reaction mixture was gradually raised to 110 C to expel the ethyl chloride, the yield of the latter (boiling at 130 C) being % of theory Fractionation of the main product by means of a 2-foot column packed with glass helices gave a yield of 67 %' of diethyl vinyl phosphate boiling at 790 C. ( 5-7 mm) and having n DD= 1 4100 and sp.gr 35/4 = 1 0724 The compound reacted vigorously with bromine and had an intense infra-red absorption band at 6 1 microns (absorption characteristic of the vinyl group). EXAMPLE 2 -

Under conditions similar to those of Example 1 trischlorethyl phosphite was reacted in equimolar proportions with monochloracetaldehyde, yielding the product bis-chlorethyl vinyl phosphate, boiling at 133-148 C. under 1 mm pressure EXAMPLE 3. To 35 4 grams ( 0 45 mole) of chloracetaldehyde were added 156 7 grams ( 0 45 mole) of bis-2-( 21 methoxyethoxy)-ethyl benzene-phosphonire at 55-75 C The reaction was only mildly exothermic and it was necessary to apply heat in order to maintain the desired temperature When the mixing operation was complete the temperature was raised to 125 C, to complete the reaction, and the pressure was then reduced to 1 mm. while still heating at 125 C to remove the byproduct 2-( 21-methoxyethoxy)-ethyl chloride. The yield of by-product was 80 % of theory, and the yield of crude 2-( 21-methoxyethoxy)ethyl vinyl benzene-phosphonate was 107 % of theory Calculated for CQH,,0 P: P= 10 8 %. Found: P= 10 9 %. Further examples of products of the general formula: piO Ii C / P -C = C A ' I?, which can be made by the process of this invention are those having the substituents given in the following Table. R 2 Et O Et O CHI -CCH 3 Et O Et O H -CH 2 C 1 Et O Et O H -CHCICHII,


* GB784986 (A)

Description: GB784986 (A) ? 1957-10-23

Manufacture of organic phosphorus compounds



The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete, up-to-date or fit for specific purposes.

PATENT SPECIFICATION 784,986 Date of Application and filing Complete Specification: Oct 28, 1953. No 6974/57. Application made in United States of America on Oct 29, 1952. Application made in United States of America on April 15, 1953. Application made in United States of America on April 15, 1953. (Divided out of No 783,697). Complete Specification Published: Oct 23, 1957. Index at acceptance:-Classes 2 ( 3), C 1 A( 12: 19: 22), C 1 B( 7: 13); and 81 ( 1), E 1 A 4 A( 2: 3: 4), E 1 C 4 A( 2: 3: 4). International Classification:-A 611 C 07 f. COMPLETE SPECIFICATION Manufacture of Organic Phosphorus Compounds We, FOOD MACHINERY AND CHEMICAL CORPORATION, a Corporation organised according to the laws of the State of New York, of 161, East 42nd Street, New York 17, State of New York, United States of America, do hereby declare the invention, for which we pray that a paternt 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 provides esters of acids of pentavalent phosphorus, which esters have the general formula /_P O-c C -II in which X 1 and X 2 are halogen atoms, R, and R, are substituted or unsubstituted alkyl, aryl, alkoxy, aryloxy or alkylamido or arylamido groups or R, and R 2 together form an unsubstituted or substituted divalent alkylenedioxy or arylenedioxy group, R 3 is hydrogen or an unsubstituted or substituted alkyl or aryl group, R 4 and R, are hydrogen or halogen atoms or unsubstituted or substituted alkyl or aryl groups, or R, and R 4 together or R, and R, together form an unsubstituted or substituted divalent alkylene or cycloalkylene group. The invention also provides a process for the manufacture of the esters of the above general formula, wherein an alkenyl ester of an acid of pentavalent phosphorus of the general formula p O-C=C -R 5 R 2 in which R 1, R 2, R 3, R 4 and R, have the meanings given above, is reacted with an appropriate elemental halogen, halogen-halide or other halogenating agent.

The halogen may be introduced by carrying out the reaction in the presence or absence of a suitable inert solvent, such as chlorinated solvent, for example, carbon tetrachloride, in the presence or absence of actinic radiation, and at temperatures ranging from O C or lower, up to about 100 C or even as high as the boiling point of the alkenyl ester used as starting material The halogenation temperature used, either in the liquid or gas phase, is a function at least in part of the thermal stability of the reactants and products The halogen may be used in the elemental state, which may be solid, liquid or gaseous Mixed halogens may also be used, for example, a mixture of chlorine and bromine, which yields a compound containing both chlorine and bromine Also, halogen may be introduced by means of an interhalogen compound (halogen-halide) or halogenating agent or carrier, such as iodine chloride, antimony pentachloride or dioxane bromine addition product. The preferred method for introduction of a halogen is to add elemental halogen to a solution of the vinyl compound in a chlorinated solvent, such as carbon tetrachloride, at a temperature of about 40-60 C Actinic light may be advantageously used to accelerate the reaction when the vinyl radical carries electronegative atoms or groups, such as halogen atoms, but in their absence such activation is unnecessary The halogen and the vinyl compound are preferably reacted in equimolar proportions, but other proportions may be effectively used. The following Examples and Table 1 illustrate this form of the invention: EXAMPLE 1. In a 250 minl capacity 3-neck flask equipped with a stirrer, graduated dropping funnel, and an adaptor bearing a Dry Ice condenser and thermometer dipping into the contents of the flask, were placed 10 ml of carbon tetrachloride and 50 5 grams ( 0 28 mole) of diethyl vinyl phosphate A Dry Ice condenser was then connected to the top of the dropping funnel, and gaseous chlorine was introduced into the condenser until 13 ml. ( 0.28 mole) of liquid chlorine had collected in the dropping funnel The liquid chlorine was introduced dropwise into the stirred solution of diethyl vinyl phosphate, which was cooled to maintain it at a temperature of 0-10 C The reaction was instantaneous and much heat was evolved When addition of the chlorine was complete stirring was continued until the reaction mixture had warmed to room temperature The solvent was removed by heating at C under a pressure of 15 mm of mercury, leaving a crude product weighing 67 6 grams, which is 96 % of theory Distillation of the crude product under 1 mm pressure gave 56 6 grams of diethyl 1: 2-dichlorethyl phosphate distilling at 75-92 C and having sp gr.

35/4 1 2549 and N 3 "D = 1 4346 The weight of distilled product represents an 81 %' yield. Calcd for CAH 13 Cl OP: Cl, 28 3 %'; P, 12.4 % Found: C 1, 26 O %; P 12 1,. EXAMPLE 2. In the apparatus described in Example 1, except that the Dry Ice condensers were eliminated, 20 grams ( 0 125 mole) of bromine were added dropwise to 31 grams ( 0 15 mole) of diethyl 2:2-dimethylvinyl phosphate dissolved in 52 ml of carbon tetrachloride, the solution being cooled to maintain a temperature of approximately O C Removal of the solvent in vacua left a 99 6 % yield of diethyl 1:2dibromo-2-methylpropyl phosphate Calculated for CH,7 Br 2 OP: Br= 434 %; P= 8 4 %. Found: Br= 43 5 %; P= 8 6 %. EXAMPLE 3. Using the apparatus and method of Example 2, 4 1 grams ( 0 026 mole) of bromine were reacted with 6 grams ( 0 026 mole) of diethyl 1cyclohexenyl phosphate dissolved in 25 ml of carbon tetrachloride The resulting diethyl 1: 2dibromocyclohexyl phosphate was not distilled. Calculated for CQH 1,Br 2 Oz P: Br= 40 6 %; P= 7 9 %; Found: Br = 40 9 %'; P = 7 9 o EXAMPLE 4. In apparatus similar to that described in Example 1, 8 6 ml ( O 19 mole) of liquid chlorine were added gradually to 63 6 grams ( 0.2 mole) of bis-2-chloroethyl 2:2-dichlorovinyl phosphate dissolved in 59 ml of carbon tetrachloride Since the latter compound does not react readily with chlorine in the dark, the reaction mixture was illuminated with a mercury vapour lamp placed about 2 inches from the reactor The reaction mixture was not cooled and the temperature eventually rose to 74 C, when mild refluxing took place. The reaction was essentially complete as soon as all the chlorine had been added, as shown by the absence of colour in the reaction mixture 65 The solvent was removed in vacua, and the crude product, bis-2-chlorethyl 1: 2: 2: 2-tetrachlorethyl phosphate, obtained in 100 % yield, was analyzed Calculated for C 6 HC 10 O P: C 1 = 54 7 %i; P= 8 0 % Found: Cl= 53 1 %; 70 P= 8 3 %. EXAMPLE 5. Using the apparatus of Example 2 and the light from a mercury vapour lamp, 3 6 ml. ( 0.07 mole) of bromine were gradually added 75 to 30 3 grams ( 0 1 mole) of 2:2-dichlorovinyl bis-diethylamido-phosphate (Et 2 N)2 P(O) OCH=C C 12, dissolved in 55 ml of carbon tetrachloride, the mixture being cooled to maintain a temperature 80 of 57-58 C When the addition of bromine was complete, the solvent was removed in vacua, leaving a 100 % yield of crude, 1:2dibromo-2: 2-dichlorethyl

bis-diethylamidophcsphate Calculatedfor C 1 II,2 Br 2 C 12 NO P: 85 halogen= 8 6 milli-equivalents per gram; P = 6.7 % Found: halogen= 8 0 milli-equivalents per gram; P = 7 79 %. EXAMPLE 6. Using the apparatus of Example 2 and the 90 light from a mercury vapour lamp, 3 6 ml. ( 0.07 mole) of bromine were added gradually to 23 3 grams ( 0 1 mole) of 2:2-dichlorovinyl trimethylene phosphate, (CH 2),02 P(O)OCH = CC 12, dissolved in 57 ml of carbon tetra 95 chloride, the temperature rising from about C to 65 C When the colour due to bromine had disappeared, the solvent was removed in vacuo, leaving a 100 % yield of crude 1: 2-dibromo-2: 2-dichlorethyl tri 100 methylene phosphate Calculated for C 1 H 7 Br 2 C 120 P: halogen = 10 2 milliequivalents per gram; P = 7 9 %o Found: halogen= 10 1 milli-equivalents per gram; P= 8 60/o 105 EXAMPLE 7. Equimolar quantities of bromine and chlorine were reacted with diethyl vinyl phosphate to form 2-bromo-1-chlorethyl diethyl phosphate. The reaction was carried out in the apparatus 110 of Example 1 by dissolving 0 1 mole each of bromine and chlorine in 75 ml of carbon tetrachloride and gradually adding 0 2 mole ( 36 grams) of diethyl vinyl phosphate at 10-25 C No activation by light was required but 115 considerable cooling was necessary to maintain the said temperature range Removal of the carbon tetrachloride in vacua left 53 5 grams (a 91 % yield) of crude product Distillation of the product under 1 mm pressure gave 28 2 120 grams (a 48 % yield) of the product distilling at 106-112 C The distilled product had a specific gravity 35/4 = 1 4579 and n'D = 1.4518 Calculated for CGH 1,Br Cl O,P: halogen= 6 8 milli-equivalents per gram; P= 125 10.4 % Found: halogen= 6 7 miilli-equivalents per gram; P= 10 0 %. 784,986 784,986 3 Ex AMPLE 8. Using the apparatus of Example 1, 7 1 mal. ( 0.15 mole) of liquid chlorine were added gradually to 42 9 grams ( 0 15 mole) of mnethioxycthioxyethyl vinyl b;nzene phosphonale Ph P(O) ( O OH CH,)OCIH 2-C Hd OCH 2 CH,,OCH,, dissolved in 62 ml of carbon tetrachioride. Activation of the chlorine by light was not necessary, but cooling of the reaction mixture was necessary to maintain the desired temperature range of 40- 45 O C Removal of the solvent in vacuo left a 100 % yield of 1: 2dichlorethyl methoxyethoxyethyl benzenephosphonate ( 54 grams) Calculated for C 1 H,1 C,02 P:cl=-198 %; P = 8 7 %. Found: Cl= 21 1 %; P= 18 8 %. Ri R Et OEt OAdditional examples of the new compounds of this invention are given in Table 1, in which the compounds are identified by reference to, the groups 'R 1, R, R,, R,, R, and the 20 halogens X,

and X 2, in the general formula: ,0 34 1,' j R, R, R,, X 2 H cl cl Br Br Et OEt On-Pr OEt OEt OMce OC 2 H 4 11 00 z 4 Et OEt OEt On-Pr O Et OEt OMe OCJ 4,O 1 z II 40Et Oi-Bu OH H Me H HI Br Br H Br Br H cl cl Br Br H H cl Br Br Me H H 01 cl HI cl cl Br Br C 1 CH 2 H H cl H cl Br Er Br Br 1 > 5 C Ha CH(CO 2 Eff)O n-Bu OC 2,H 4 OCCI 3 CH 2 OBu CH Et CH 20Et OCe Vi C# CM, 0\\ O CW,-ei CH,1 CH(C 02 Et)On-Bu OCJ,H 01 CGC 11 C 2 OBu CH Et CH 20Et OH cl cl Br Br H cl cl Br Br H cl cl Br Br H cl cl Br Br H cl cl Br Br HI H cl cl cl Me CO 2 Et Cl Br Br H 'Cl cl Br Br Cli 0 CICH 2 CH 2 OCICH 2 CH 20C 1 C H 2 C H 2 O C l C HI C I H 20 H cl cl Br Br H cl Cl cl cl Et OEt O784,986 CIGHCH,0784,986 TABLE 1-continued. R 2 H Cl C 1 Br Br Et OEt OCl CH, CH 20Cl CH 2 CH 20CICH 2 CH 20Me OCH 10 C 2 H t OCl CH 2 CH 20CICCHC 20CICH 2 CH 20H Br Br Br Br H H H Br Br H H H Br Br H H Cl Br Br H H Cl Cl Cl The compounds of this invention are useful in a wide range of valuable and interesting applications, for example, as biocides and medicaments Some of the compounds exhibit extremely interesting properties as rodenticides Others are potent contact insecticides and acaricides Still others are particularly effective as systemic insecticides or acar-icids. Some of the compounds show promise as powerful cholinesterase inhibitors Examples of these biocidal properties are set forth in Tables 2 and 3. Conc 2-Spotted Pea Compound ppm Mite Aphid A B 150 TABLE 2 Contact Insecticidal and Acaricidal Activity The contact insecticidal and acaricidal activity of these products is illustrated in the following table The materials were formulated as 15 % wettable powders, diluted with water to the desired concentration, and sprayed on suitable plant foliage The treated plants were then infested with the desired insect, and mortality counts, shown as percentages, were taken 72 hours later. German Milkwood Mex Bean Roach Bug Beetle C 156 7 30 6 ' + e = necab/,; t/ 784,986 Compound C Conc. ppm D 150 TABLE-continued 2-Spotted Pea Mite Aphid German Millwood Mex Bean Roach Bug Beetle E 156 F 156 2.5 G 1250 156 A = (Et O)2 P(O)OCH Br-CH 2 Br B = (Et O)2 P(O)OCH Br CH Br Cl C = (Et O)2 P(O)OCHC 1 HC 12 D = (Et O)2 P(O)OCHCICC 13 TABLE 3 Systemic Insecticidal and Acaricidal Activities. The systemic insecticidal and acaricidal activities of these products are illustrated in E = (Et O)2 P(O)OCH Br C Br 3 F = (Et O)2 P(O)OCHC 1 CH 2 Br G = (CICH 2 CH 2 O)2 P(O)OCH Cl CHCI 2 the following table Stems of excised bean plants were placed in test tubes containing 25 ml of a solution or emulsion of the active material in water, and the plants were held in 10 place by non-absorbent cotton plugs which also prevented evaporation The plants were days later Data obtained with

Systox (the then infested with two-spotted mites or pea word "Systox" being a registered Trade Mark) aphids, and mortality counts were taken 4 are shown for comparison. Mites Aphids Compound Conc ppm % Kill Conc ppm % Kill A 78 100 20 100 100 10 100 100 5 85 95 2.5 45 B 156 100 156 100 78 100 39 100 100 10 100 100 5 100 96 2 5 80 1.25 63 1 25 70 0.625 26 0 625 15 C 78 100 20 100 100 10 100 98 5 100 84 2 5 50 2.5 50 1.25 25 D 10 100 10 100 100 5 100 2.5 27 2 5 100 1.25 23 1 25 85 0.625 20 0 625 80 A -= (Et O)2 P(O)OC(CH 3)CI-CH 2 Cl B= (Et O)2 P(O)OCHCICH C 12 C = (Et O)2 P(O)OCH Br CH Br CI D Systox (Et O)2 P(S)OCH 2 CH 25 C 2 H 5 784,986 valent phosphorus given in Table 1 herein, with the exception of the compounds claimed in claims 10 to 15. 17 A process for the manufacture of an 45 ester claimed in any one of claims 1 to 16, wherein an alkenyl ester of an acid of pentavalent phosphorus of the general formula R/.P o-e=e-, 5 R 2 R


* GB784987 (A)

Description: GB784987 (A) ? 1957-10-23

Improvements in or relating to the bonding of metal to moulded compositions



The EPO does not accept any responsibility for the accuracy of data and information originating from other authorities than the EPO; in particular, the EPO does not guarantee that they are complete,

up-to-date or fit for specific purposes.

e ri A f C 7 RI PATENT SPECIFICATION Inventors: GORDON ARTHUR CAPEWELL and GEORGE WILLIAM RIPPINGTON Date of filing Complete Specification Feb 25, 1954. Application Date May 7, 1953. 784987 No 12806/53. I/ r 'Complete Specification Published Oct 23, 1957. Index at Acceptance:-Classes 87 ( 2), Al R 14 (A: C 2: D), A 1 R 39 X; and 140, A 2 (F: A: H: M 5); A 5 G( 1 A: 1 B: 4: 8: 9), A 16 A. International Classification: -B 29 d, g. COMPLETE SPECIFICATION Improvements in or relating to the Bonding of Metal to Moulded Compositions ERRATA SPECIFICATION No 784,987 Page 1, line 53, for "polyivnyl-butyral" read "polyvinyl-butyrai" Page 5, line 23, for " 1,700 lbs -sq in " read " 1,700 lbs /sq in " THE PATENT OFFICE, 13th Yanuary, 1958. O i 5 organic or inorganic and natural or synthetic and may be in any state of sub-division, and bonding agents comprising thermosetting or thermoplastic resins The fillers may be fibrous or non-fibrous and in the former case may take the form of filaments or yarns which may be woven or felted Examples of fibrous fillers in their various forms are glass filaments randomly disposed in the form of a mat or web, nylon yarns woven into a fabric, cotton yarns in the form of a woven fabric and cut into pieces, treated wood fibres in the form of paper sheets, wood fibres in the form of a flour and asbestos fibres in the form of a flock. The process of bonding a metal component to the surface of a moulded composition may be carried out either by bonding the component, e g, with adhesive, to a premoulded composition or by bonding the component to the moulded composition during the process of lP) carrying out the processes of bonding and moulding simultaneously. Where the moulded composition and the metal component are bonded together during the moulding process it is possible to establish a bond between the two without the use of a special adhesive, but it has been found that an improved bond is obtained in many cases by interposing an adhesive, such as a phenol-formaldehyde/polyvinyl-butyral resin mixture, between the metal component and the moulded composition. According to the present invention there is provided a method for forming a moulded product embodying as a surface layer a metal component which method comprises the provision of a layer comprising an amino-formaldehyde resin between the said surface metal component

and a mouldable composition comprising a filler and a bonding agent, the provision of a layer of adhesive between the layer tt,' PY X PATENT SPECIFICATION Inventors: GORDON ARTHUR CAPEWELL and GEORGE WILLIAM RIPPINGTON Date of filing Complete Specification Feb 25, 1954. Application Date May 7, 1953. 784987 No 12806/53. > Complete Specification Published Oct23, 1957. Index at Acceptance:-Classes 87 ( 2), AIR 14 (A: C 2: D), A 1 R 39 X; and 140, A 2 (F: 'G: H: M 5); A 5 G( 1 A: 1 B: 4: 8: 9), A 16 A. International Classification: -B 29 d, g. COMPLETE SPECIFICATION Improvements in or relating to the Bonding of Metal to Moulded Compositions We, BAKELITE LIMITED, a British Company, of 12, Hobart Place, London, S W 1, 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 is for improvements in the bonding of metal components to moulded compositions comprising a filler and a bonding agent. The combination of metals and moulded compositions comprising a filler and a bonding agent is widely practised Typical examples of metal surfaced products are mouldings produced from moulding powders bearing a decorative metal foil and laminated materials bearing e g a copper foil, which are used for the production of printed electrical circuits. The invention may be applied to the union of metals of all kldnds with moulded compositions comprising fillers, which may be organic or inorganic and natural or synthetic and may be in any state of sub-division, and bonding agents comprising thermosetting or thermoplastic resins The fillers may be fibrous or non-fibrous and in the former case may take the form of filaments or yarns which may be woven or felted Examples of fibrous fillers in their various forms are glass filaments randomly disposed in the form of a mat or web, nylon yarns woven into a fabric, cotton yarns in the form of a woven fabric and cut into pieces, treated wood fibres in the form of paper sheets, wood fibres in the form of a flour and asbestos fibres in the form of a flock. The process of bonding a metal component to the surface of a moulded composition may be carried out either by bonding the component, e g, with adhesive, to a premoulded composition or by bonding the component to the moulded composition during the process of lPl _ moulding the latter It has hitherto been 45 found that the former (two-stage) method has given a bond superior to that produced by the latter

(one-stage) method. Although the two-stage process in which the metal component is bonded to the surface 50 of the premoulded composition by means of an adhesive, consisting e g of a phenol-formaldehyde/polyivnyl-butyral resin mixture, gives a superior bond, the process suffers from two main defects, viz ( 1) it is longer and 55 is, therefore, more expensive than the onestage process, and ( 2) where a metal component, particularly in the form of a foil, is applied to a premoulded composition it is difficult to ensure complete elimination of the air trapped 60 between the component and the composition and the bond is thus weakened at those points where this occurs. It is an aim of the present invention try obtain an improved bond between a surface 65 metal component and a moulded composition comprising a filler and a bonding agent while carrying out the processes of bonding and moulding simultaneously. Where the moulded composition and the 70 metal component are bonded together during the moulding process it is possible to establish a bond between the two without the use of a special adhesive, but it has been found that an improved bond is obtained in many 75 cases by interposing an adhesive, such as a phenol-formaldehyde/polyvinyl-butyral resin mixture, between the metal component and the moulded composition. According to the present invention there is 80 provided a method for forming a moulded product embodying as a surface layer a metal component which method comprises the provision of a layer comprising an amino-formaldehyde resin between the said surface metal 85 component and a mouldable composition comprising a filler and a bonding agent, the provision of a layer of adhesive between the layer b 2 784,9 7 comprising the amino-formaldehyde resin and the metal component and subjecting the assembly to moulding conditions. The term "metal component" includes metal sheets foils and blocks. In the one-step process of bonding, e g. copper foil to the surface of a laminated product based on paper impregnated with a phenol-formaldehyde thermosetting resin, hitherto it has been found that the best bond has been obtained by applying a suitable adhesive, e g a mixture comprising phenol-formaldehyde resin and polyivnyl-butyral resin, to the surfaces of the copper foil and/or the resin impregnated sheets of paper where they are in contact and then subjecting the stacked assembly to heat and pressure The bond, however, has not been entirely satisfactory, particularly where the copper-faced laminated product has been used in the production of printed circuits; thus where electrical components have been fixed thereto there has been a tendency for the bond btween the copper foil and the insulating base to be broken.

We have now found that it is possible to unite more effectively a surface metal component and a moulded composition comprising a filler and a bonding agent when using the onestep process of manufacture by interposing a layer comprising an amino-formaldehyde resin between the mouldable composition and the adhesive for the metal component The amino-formaldehyde resin may be in the form of a supported or an unsupported film Thus it may be applied to a sheet of fibrous material e.g, a sheet of paper, before being interposed between the adhesive layer and the mouldable composition or it may be applied as a solution to, e g, the adhesive-treated metal component and allowed to dry before the mould?ing operation takes place. The amino-formaldehyde resin has further advantages when used in the production of electrical products and particularly where the bonding agent of the moulded composition is a relatively poor anti-tracking material Thus, a melamine-formaldehyde resin is obviously advantageous in the production of printed electrical circuits where the bonding agent of the moulded composition is a relatively poor anti-tracking material, e g a phenol-formaldehyde resin In a combination utilising a layer comprising a melamine-formaldehyde resin, it has been observed that the union between the metal component and the moulded composition is stronger than in the case where a urea-formaldehyde layer is used. The adhesive for the metal may be applied in a number of ways For example, it may be applied to the metal component, or to the sheet of paper treated with the amino-formaldehyde resin or to both, or it may be inter, posed between the metal and the amino-formaldehyde layer as a supported or unsupported film. In some cases it is preferable to etch the metal component before bonding it to the moulded composition and this may be done chemically or mechanically In some instances, e.g in the case of electro-deposited copper foil, a suitably etched surface is produced during manufacture. Following is a description by way of example of methods of carrying the invention into effect. EXAMPLE I Electro-deposited copper foil O 002 " thick was coated on its etched surface with a layer consisting of a blend in organic solvent of equal proportions by weight of a heat-hardenable phenol-formaldehyde resin and a polyvinyl butyral resin The coated metal was dried at 90 to 160 C for 20 to 230 minutes. A stack was then built up as follows:1 sheet of copper foil treated as described above (adhesive-treared surface uppermost). A layer consisting of a sheet of x-cellulose paper (O j 015 " thick) impregnated with melamine-formaldehyde resin to a resin content of 55 G'.

sheets of cotton based paper ( 0 005 ' thick) impregnated with cresol-formaldehyde resin to give a final resin content of 55 %o. A layer consisting of a sheet of >-cellulose paper impregnated with melanmir ne-formaldehyde resin as above. 1 sheet of copper foil as abeve (adhesive treated surface downwards). The stack was pressed between polished steel plates for 30 minutes at 170 C under a pressure of 1,700 lb /sq in The resulting sheet which consisted of a paper filled laminated product faced on both sides with copper foil was cooled under pressure before removing it from the press. EXAMPLE II A stack was built up as follows:1 sheet of aluminium 7/,' thick etched on 110 one surface only and with the etched surface uppermost. A layer consisting of a sheet of 7 -cellulose paper ( O 0015 " thick) treated with a melamine-formaldehyde resin to give a final 115 resin content of 55 % and subsequently coated on the surface to contact the metal sheet with a blend of equal proportions of heat-hardenable phenol-forfmaldehlydj resin and polyvinyl butyral to give an 120 adhesive content of 5 %. x '/,th" gaboon veneers with a liquid phenol-formaldehyde glue interposed. A melamine-formaldehyde layer consisting of a sheet as above, with the adhesive 125 coated surface uppermost. 1 sheet of aluminium /5th" thick etched on one surface only and with the etched surface facing downwards. 784,987


4576 4580.output

Law